title: Eye

text: Eyes are organs of the visual system. They provide living organisms with vision, the ability to receive and process visual detail, as well as enabling several photo response functions that are independent of vision. Eyes detect light and convert it into electro-chemical impulses in neurons (neurones). In higher organisms, the eye is a complex optical system which collects light from the surrounding environment, regulates its intensity through a diaphragm, focuses it through an adjustable assembly of lenses to form an image, converts this image into a set of electrical signals, and transmits these signals to the brain through complex neural pathways that connect the eye via the optic nerve to the visual cortex and other areas of the brain. Eyes with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in molluscs, chordates and arthropods.


title: Eye

text: The most simple eyes, pit eyes, are eye-spots which may be set into a pit to reduce the angle of light that enters and affects the eye-spot, to allow the organism to deduce the angle of incoming light. From more complex eyes, retinal photosensitive ganglion cells send signals along the retinohypothalamic tract to the suprachiasmatic nuclei to effect circadian adjustment and to the pretectal area to control the pupillary light reflex.


title: Eye

text: Complex eyes distinguish shapes and colours. The visual fields of many organisms, especially predators, involve large areas of binocular vision for depth perception. In other organisms, particularly prey animals, eyes are located to maximise the field of view, such as in rabbits and horses, which have monocular vision.


title: Eye

text: The first proto-eyes evolved among animals about the time of the Cambrian explosion. The last common ancestor of animals possessed the biochemical toolkit necessary for vision, and more advanced eyes have evolved in 96% of animal species in six of the ~35 main phyla. In most vertebrates and some molluscs, the eye allows light to enter and project onto a light-sensitive layer of cells known as the retina. The cone cells (for colour) and the rod cells (for low-light contrasts) in the retina detect and convert light into neural signals which are transmitted to the brain via the optic nerve to produce vision. Such eyes are typically spheroid, filled with the transparent gel-like vitreous humour, possess a focusing lens, and often an iris. Muscles around the iris change the size of the pupil, regulating the amount of light that enters the eye and reducing aberrations when there is enough light. The eyes of most cephalopods, fish, amphibians and snakes have fixed lens shapes, and focusing is achieved by telescoping the lens in a similar manner to that of a camera.


title: Eye

text: The compound eyes of the arthropods are composed of many simple facets which, depending on anatomical detail, may give either a single pixelated image or multiple images per eye. Each sensor has its own lens and photosensitive cell(s). Some eyes have up to 28,000 such sensors arranged hexagonally, which can give a full 360° field of vision. Compound eyes are very sensitive to motion. Some arthropods, including many Strepsiptera, have compound eyes of only a few facets, each with a retina capable of creating an image. With each eye producing a different image, a fused, high-resolution image is produced in the brain.


title: Eye

text: Possessing detailed hyperspectral colour vision, the Mantis shrimp has the world's most complex colour vision system. Trilobites, now extinct, had unique compound eyes. Clear calcite crystals formed the lenses of their eyes. They differ in this from most other arthropods, which have soft eyes. The number of lenses in such an eye varied widely; some trilobites had only one while others had thousands of lenses per eye.


title: Eye

text: In contrast to compound eyes, simple eyes have a single lens. Jumping spiders have one pair of large simple eyes with a narrow field of view, augmented by an array of smaller eyes for peripheral vision. Some insect larvae, like caterpillars, have a type of simple eye (stemmata) which usually provides only a rough image, but (as in sawfly larvae) can possess resolving powers of 4 degrees of arc, be polarization-sensitive, and capable of increasing its absolute sensitivity at night by a factor of 1,000 or more. Ocelli, some of the simplest eyes, are found in animals such as some of the snails. They have photosensitive cells but no lens or other means of projecting an image onto those cells. They can distinguish between light and dark but no more, enabling them to avoid direct sunlight.


title: Eye

text: In organisms dwelling near deep-sea vents, compound eyes are adapted to see the infra-red light produced by the hot vents; enabling the creatures to avoid being boiled alive.


title: Eye

text: There are ten different eye layouts—indeed every technological method of capturing an optical image commonly used by human beings, with the exceptions of zoom and Fresnel lenses, occur in nature. Eye types can be categorised into "simple eyes", with one concave photoreceptive surface, and "compound eyes", which comprise a number of individual lenses laid out on a convex surface. Note that "simple" does not imply a reduced level of complexity or acuity. Indeed, any eye type can be adapted for almost any behaviour or environment. The only limitations specific to eye types are that of resolution—the physics of compound eyes prevents them from achieving a resolution better than 1°. Also, superposition eyes can achieve greater sensitivity than apposition eyes, so are better suited to dark-dwelling creatures. Eyes also fall into two groups on the basis of their photoreceptor's cellular construction, with the photoreceptor cells either being cilliated (as in the vertebrates) or rhabdomeric. These two groups are not monophyletic; the cnidaria also possess cilliated cells,


title: Eye

text: Some organisms have photosensitive cells that do nothing but detect whether the surroundings are light or dark, which is sufficient for the entrainment of circadian rhythms. These are not considered eyes because they lack enough structure to be considered an organ, and do not produce an image.


title: Eye

text: Simple eyes are rather ubiquitous, and lens-bearing eyes have evolved at least seven times in vertebrates, cephalopods, annelids, crustaceans and cubozoa.


title: Eye

text: Pit eyes, also known as stemma, are eye-spots which may be set into a pit to reduce the angles of light that enters and affects the eye-spot, to allow the organism to deduce the angle of incoming light. Found in about 85% of phyla, these basic forms were probably the precursors to more advanced types of "simple eyes". They are small, comprising up to about 100 cells covering about 100 µm. The directionality can be improved by reducing the size of the aperture, by incorporating a reflective layer behind the receptor cells, or by filling the pit with a refractile material.


title: Eye

text: Pit vipers have developed pits that function as eyes by sensing thermal infra-red radiation, in addition to their optical wavelength eyes like those of other vertebrates (see infrared sensing in snakes). However, pit organs are fitted with receptors rather different from photoreceptors, namely a specific transient receptor potential channel (TRP channels) called TRPV1. The main difference is that photoreceptors are G-protein coupled receptors but TRP are ion channels.


title: Eye

text: The resolution of pit eyes can be greatly improved by incorporating a material with a higher refractive index to form a lens, which may greatly reduce the blur radius encountered—hence increasing the resolution obtainable. The most basic form, seen in some gastropods and annelids, consists of a lens of one refractive index. A far sharper image can be obtained using materials with a high refractive index, decreasing to the edges; this decreases the focal length and thus allows a sharp image to form on the retina. This also allows a larger aperture for a given sharpness of image, allowing more light to enter the lens; and a flatter lens, reducing spherical aberration. Such a non-homogeneous lens is necessary for the focal length to drop from about 4 times the lens radius, to 2.5 radii.


title: Eye

text: Heterogeneous eyes have evolved at least nine times: four or more times in gastropods, once in the copepods, once in the annelids, once in the cephalopods, and once in the chitons, which have aragonite lenses. No extant aquatic organisms possess homogeneous lenses; presumably the evolutionary pressure for a heterogeneous lens is great enough for this stage to be quickly "outgrown".


title: Eye

text: This eye creates an image that is sharp enough that motion of the eye can cause significant blurring. To minimise the effect of eye motion while the animal moves, most such eyes have stabilising eye muscles.


title: Eye

text: The ocelli of insects bear a simple lens, but their focal point usually lies behind the retina; consequently, those can't form a sharp image. Ocelli (pit-type eyes of arthropods) blur the image across the whole retina, and are consequently excellent at responding to rapid changes in light intensity across the whole visual field; this fast response is further accelerated by the large nerve bundles which rush the information to the brain. Focusing the image would also cause the sun's image to be focused on a few receptors, with the possibility of damage under the intense light; shielding the receptors would block out some light and thus reduce their sensitivity.


title: Eye

text: This fast response has led to suggestions that the ocelli of insects are used mainly in flight, because they can be used to detect sudden changes in which way is up (because light, especially UV light which is absorbed by vegetation, usually comes from above).


title: Eye

text: Some marine organisms bear more than one lens; for instance the copepod "Pontella" has three. The outer has a parabolic surface, countering the effects of spherical aberration while allowing a sharp image to be formed. Another copepod, "Copilia", has two lenses in each eye, arranged like those in a telescope. Such arrangements are rare and poorly understood, but represent an alternative construction.


title: Eye

text: Multiple lenses are seen in some hunters such as eagles and jumping spiders, which have a refractive cornea: these have a negative lens, enlarging the observed image by up to 50% over the receptor cells, thus increasing their optical resolution.


title: Eye

text: In the eyes of most mammals, birds, reptiles, and most other terrestrial vertebrates (along with spiders and some insect larvae) the vitreous fluid has a higher refractive index than the air. In general, the lens is not spherical. Spherical lenses produce spherical aberration. In refractive corneas, the lens tissue is corrected with inhomogeneous lens material (see Luneburg lens), or with an aspheric shape. Flattening the lens has a disadvantage; the quality of vision is diminished away from the main line of focus. Thus, animals that have evolved with a wide field-of-view often have eyes that make use of an inhomogeneous lens.


title: Eye

text: As mentioned above, a refractive cornea is only useful out of water. In water, there is little difference in refractive index between the vitreous fluid and the surrounding water. Hence creatures that have returned to the water—penguins and seals, for example—lose their highly curved cornea and return to lens-based vision. An alternative solution, borne by some divers, is to have a very strongly focusing cornea.


title: Eye

text: An alternative to a lens is to line the inside of the eye with "mirrors", and reflect the image to focus at a central point. The nature of these eyes means that if one were to peer into the pupil of an eye, one would see the same image that the organism would see, reflected back out.


title: Eye

text: Many small organisms such as rotifers, copepods and flatworms use such organs, but these are too small to produce usable images. Some larger organisms, such as scallops, also use reflector eyes. The scallop "Pecten" has up to 100 millimetre-scale reflector eyes fringing the edge of its shell. It detects moving objects as they pass successive lenses.


title: Eye

text: There is at least one vertebrate, the spookfish, whose eyes include reflective optics for focusing of light. Each of the two eyes of a spookfish collects light from both above and below; the light coming from above is focused by a lens, while that coming from below, by a curved mirror composed of many layers of small reflective plates made of guanine crystals.


title: Eye

text: A compound eye may consist of thousands of individual photoreceptor units or ommatidia (ommatidium, singular). The image perceived is a combination of inputs from the numerous ommatidia (individual "eye units"), which are located on a convex surface, thus pointing in slightly different directions. Compared with simple eyes, compound eyes possess a very large view angle, and can detect fast movement and, in some cases, the polarisation of light. Because the individual lenses are so small, the effects of diffraction impose a limit on the possible resolution that can be obtained (assuming that they do not function as phased arrays). This can only be countered by increasing lens size and number. To see with a resolution comparable to our simple eyes, humans would require very large compound eyes, around in radius.


title: Eye

text: Compound eyes fall into two groups: apposition eyes, which form multiple inverted images, and superposition eyes, which form a single erect image. Compound eyes are common in arthropods, annelids and some bivalved molluscs. Compound eyes in arthropods grow at their margins by the addition of new ommatidia.


title: Eye

text: Apposition eyes are the most common form of eyes and are presumably the ancestral form of compound eyes. They are found in all arthropod groups, although they may have evolved more than once within this phylum. Some annelids and bivalves also have apposition eyes. They are also possessed by "Limulus", the horseshoe crab, and there are suggestions that other chelicerates developed their simple eyes by reduction from a compound starting point. (Some caterpillars appear to have evolved compound eyes from simple eyes in the opposite fashion.)


title: Eye

text: Apposition eyes work by gathering a number of images, one from each eye, and combining them in the brain, with each eye typically contributing a single point of information. The typical apposition eye has a lens focusing light from one direction on the rhabdom, while light from other directions is absorbed by the dark wall of the ommatidium.


title: Eye

text: The refracting superposition eye has a gap between the lens and the rhabdom, and no side wall. Each lens takes light at an angle to its axis and reflects it to the same angle on the other side. The result is an image at half the radius of the eye, which is where the tips of the rhabdoms are. This type of compound eye, for which a minimal size exists below which effective superposition cannot occur, is normally found in nocturnal insects, because it can create images up to 1000 times brighter than equivalent apposition eyes, though at the cost of reduced resolution. In the parabolic superposition compound eye type, seen in arthropods such as mayflies, the parabolic surfaces of the inside of each facet focus light from a reflector to a sensor array. Long-bodied decapod crustaceans such as shrimp, prawns, crayfish and lobsters are alone in having reflecting superposition eyes, which also have a transparent gap but use corner mirrors instead of lenses.


title: Eye

text: This eye type functions by refracting light, then using a parabolic mirror to focus the image; it combines features of superposition and apposition eyes.


title: Eye

text: Another kind of compound eye, found in males of Order Strepsiptera, employs a series of simple eyes—eyes having one opening that provides light for an entire image-forming retina. Several of these "eyelets" together form the strepsipteran compound eye, which is similar to the 'schizochroal' compound eyes of some trilobites. Because each eyelet is a simple eye, it produces an inverted image; those images are combined in the brain to form one unified image. Because the aperture of an eyelet is larger than the facets of a compound eye, this arrangement allows vision under low light levels.


title: Eye

text: Good fliers such as flies or honey bees, or prey-catching insects such as praying mantis or dragonflies, have specialised zones of ommatidia organised into a fovea area which gives acute vision. In the acute zone, the eyes are flattened and the facets larger. The flattening allows more ommatidia to receive light from a spot and therefore higher resolution. The black spot that can be seen on the compound eyes of such insects, which always seems to look directly at the observer, is called a pseudopupil. This occurs because the ommatidia which one observes "head-on" (along their optical axes) absorb the incident light, while those to one side reflect it.


title: Eye

text: There are some exceptions from the types mentioned above. Some insects have a so-called single lens compound eye, a transitional type which is something between a superposition type of the multi-lens compound eye and the single lens eye found in animals with simple eyes. Then there is the mysid shrimp, "Dioptromysis paucispinosa". The shrimp has an eye of the refracting superposition type, in the rear behind this in each eye there is a single large facet that is three times in diameter the others in the eye and behind this is an enlarged crystalline cone. This projects an upright image on a specialised retina. The resulting eye is a mixture of a simple eye within a compound eye.


title: Eye

text: Another version is a compound eye often referred to as "pseudofaceted", as seen in "Scutigera". This type of eye consists of a cluster of numerous ommatidia on each side of the head, organised in a way that resembles a true compound eye.


title: Eye

text: The body of "Ophiocoma wendtii", a type of brittle star, is covered with ommatidia, turning its whole skin into a compound eye. The same is true of many chitons. The tube feet of sea urchins contain photoreceptor proteins, which together act as a compound eye; they lack screening pigments, but can detect the directionality of light by the shadow cast by its opaque body.


title: Eye

text: The ciliary body is triangular in horizontal section and is coated by a double layer, the ciliary epithelium. The inner layer is transparent and covers the vitreous body, and is continuous from the neural tissue of the retina. The outer layer is highly pigmented, continuous with the retinal pigment epithelium, and constitutes the cells of the dilator muscle.


title: Eye

text: The vitreous is the transparent, colourless, gelatinous mass that fills the space between the lens of the eye and the retina lining the back of the eye. It is produced by certain retinal cells. It is of rather similar composition to the cornea, but contains very few cells (mostly phagocytes which remove unwanted cellular debris in the visual field, as well as the hyalocytes of Balazs of the surface of the vitreous, which reprocess the hyaluronic acid), no blood vessels, and 98–99% of its volume is water (as opposed to 75% in the cornea) with salts, sugars, vitrosin (a type of collagen), a network of collagen type II fibres with the mucopolysaccharide hyaluronic acid, and also a wide array of proteins in micro amounts. Amazingly, with so little solid matter, it tautly holds the eye.


title: Eye

text: Photoreception is phylogenetically very old, with various theories of phylogenesis. The common origin (monophyly) of all animal eyes is now widely accepted as fact. This is based upon the shared genetic features of all eyes; that is, all modern eyes, varied as they are, have their origins in a proto-eye believed to have evolved some 650-600 million years ago, and the PAX6 gene is considered a key factor in this. The majority of the advancements in early eyes are believed to have taken only a few million years to develop, since the first predator to gain true imaging would have touched off an "arms race" among all species that did not flee the photopic environment. Prey animals and competing predators alike would be at a distinct disadvantage without such capabilities and would be less likely to survive and reproduce. Hence multiple eye types and subtypes developed in parallel (except those of groups, such as the vertebrates, that were only forced into the photopic environment at a late stage).


title: Eye

text: Eyes in various animals show adaptation to their requirements. For example, the eye of a bird of prey has much greater visual acuity than a human eye, and in some cases can detect ultraviolet radiation. The different forms of eye in, for example, vertebrates and molluscs are examples of parallel evolution, despite their distant common ancestry. Phenotypic convergence of the geometry of cephalopod and most vertebrate eyes creates the impression that the vertebrate eye evolved from an imaging cephalopod eye, but this is not the case, as the reversed roles of their respective ciliary and rhabdomeric opsin classes and different lens crystallins show.


title: Eye

text: The very earliest "eyes", called eye-spots, were simple patches of photoreceptor protein in unicellular animals. In multicellular beings, multicellular eyespots evolved, physically similar to the receptor patches for taste and smell. These eyespots could only sense ambient brightness: they could distinguish light and dark, but not the direction of the light source.


title: Eye

text: Through gradual change, the eye-spots of species living in well-lit environments depressed into a shallow "cup" shape. The ability to slightly discriminate directional brightness was achieved by using the angle at which the light hit certain cells to identify the source. The pit deepened over time, the opening diminished in size, and the number of photoreceptor cells increased, forming an effective pinhole camera that was capable of dimly distinguishing shapes. However, the ancestors of modern hagfish, thought to be the protovertebrate, were evidently pushed to very deep, dark waters, where they were less vulnerable to sighted predators, and where it is advantageous to have a convex eye-spot, which gathers more light than a flat or concave one. This would have led to a somewhat different evolutionary trajectory for the vertebrate eye than for other animal eyes.


title: Eye

text: The thin overgrowth of transparent cells over the eye's aperture, originally formed to prevent damage to the eyespot, allowed the segregated contents of the eye chamber to specialise into a transparent humour that optimised colour filtering, blocked harmful radiation, improved the eye's refractive index, and allowed functionality outside of water. The transparent protective cells eventually split into two layers, with circulatory fluid in between that allowed wider viewing angles and greater imaging resolution, and the thickness of the transparent layer gradually increased, in most species with the transparent crystallin protein.


title: Eye

text: The gap between tissue layers naturally formed a biconvex shape, an optimally ideal structure for a normal refractive index. Independently, a transparent layer and a nontransparent layer split forward from the lens: the cornea and iris. Separation of the forward layer again formed a humour, the aqueous humour. This increased refractive power and again eased circulatory problems. Formation of a nontransparent ring allowed more blood vessels, more circulation, and larger eye sizes.


title: Eye

text: Eyes are generally adapted to the environment and life requirements of the organism which bears them. For instance, the distribution of photoreceptors tends to match the area in which the highest acuity is required, with horizon-scanning organisms, such as those that live on the African plains, having a horizontal line of high-density ganglia, while tree-dwelling creatures which require good all-round vision tend to have a symmetrical distribution of ganglia, with acuity decreasing outwards from the centre.


title: Eye

text: Of course, for most eye types, it is impossible to diverge from a spherical form, so only the density of optical receptors can be altered. In organisms with compound eyes, it is the number of ommatidia rather than ganglia that reflects the region of highest data acquisition. Optical superposition eyes are constrained to a spherical shape, but other forms of compound eyes may deform to a shape where more ommatidia are aligned to, say, the horizon, without altering the size or density of individual ommatidia. Eyes of horizon-scanning organisms have stalks so they can be easily aligned to the horizon when this is inclined, for example, if the animal is on a slope.


title: Eye

text: An extension of this concept is that the eyes of predators typically have a zone of very acute vision at their centre, to assist in the identification of prey. In deep water organisms, it may not be the centre of the eye that is enlarged. The hyperiid amphipods are deep water animals that feed on organisms above them. Their eyes are almost divided into two, with the upper region thought to be involved in detecting the silhouettes of potential prey—or predators—against the faint light of the sky above. Accordingly, deeper water hyperiids, where the light against which the silhouettes must be compared is dimmer, have larger "upper-eyes", and may lose the lower portion of their eyes altogether. In the giant Antarctic isopod Glyptonotus a small ventral compound eye is physically completely separated from the much larger dorsal compound eye. Depth perception can be enhanced by having eyes which are enlarged in one direction; distorting the eye slightly allows the distance to the object to be estimated with a high degree of accuracy.


title: Eye

text: Acuity is higher among male organisms that mate in mid-air, as they need to be able to spot and assess potential mates against a very large backdrop. On the other hand, the eyes of organisms which operate in low light levels, such as around dawn and dusk or in deep water, tend to be larger to increase the amount of light that can be captured.


title: Eye

text: It is not only the shape of the eye that may be affected by lifestyle. Eyes can be the most visible parts of organisms, and this can act as a pressure on organisms to have more transparent eyes at the cost of function.


title: Eye

text: Eyes may be mounted on stalks to provide better all-round vision, by lifting them above an organism's carapace; this also allows them to track predators or prey without moving the head.


title: Eye

text: Visual acuity, or resolving power, is "the ability to distinguish fine detail" and is the property of cone cells. It is often measured in "cycles per degree" (CPD), which measures an angular resolution, or how much an eye can differentiate one object from another in terms of visual angles. Resolution in CPD can be measured by bar charts of different numbers of white/black stripe cycles. For example, if each pattern is 1.75 cm wide and is placed at 1 m distance from the eye, it will subtend an angle of 1 degree, so the number of white/black bar pairs on the pattern will be a measure of the cycles per degree of that pattern. The highest such number that the eye can resolve as stripes, or distinguish from a grey block, is then the measurement of visual acuity of the eye.


title: Eye

text: For a human eye with excellent acuity, the maximum theoretical resolution is 50 CPD (1.2 arcminute per line pair, or a 0.35 mm line pair, at 1 m). A rat can resolve only about 1 to 2 CPD. A horse has higher acuity through most of the visual field of its eyes than a human has, but does not match the high acuity of the human eye's central fovea region.


title: Eye

text: Spherical aberration limits the resolution of a 7 mm pupil to about 3 arcminutes per line pair. At a pupil diameter of 3 mm, the spherical aberration is greatly reduced, resulting in an improved resolution of approximately 1.7 arcminutes per line pair. A resolution of 2 arcminutes per line pair, equivalent to a 1 arcminute gap in an optotype, corresponds to 20/20 (normal vision) in humans.


title: Eye

text: However, in the compound eye, the resolution is related to the size of individual ommatidia and the distance between neighbouring ommatidia. Physically these cannot be reduced in size to achieve the acuity seen with single lensed eyes as in mammals. Compound eyes have a much lower acuity than vertebrate eyes.


title: Eye

text: "Colour vision is the faculty of the organism to distinguish lights of different spectral qualities." All organisms are restricted to a small range of electromagnetic spectrum; this varies from creature to creature, but is mainly between wavelengths of 400 and 700 nm.


title: Eye

text: This is a rather small section of the electromagnetic spectrum, probably reflecting the submarine evolution of the organ: water blocks out all but two small windows of the EM spectrum, and there has been no evolutionary pressure among land animals to broaden this range.


title: Eye

text: The most sensitive pigment, rhodopsin, has a peak response at 500 nm. Small changes to the genes coding for this protein can tweak the peak response by a few nm; pigments in the lens can also filter incoming light, changing the peak response. Many organisms are unable to discriminate between colours, seeing instead in shades of grey; colour vision necessitates a range of pigment cells which are primarily sensitive to smaller ranges of the spectrum. In primates, geckos, and other organisms, these take the form of cone cells, from which the more sensitive rod cells evolved. Even if organisms are physically capable of discriminating different colours, this does not necessarily mean that they can perceive the different colours; only with behavioural tests can this be deduced.


title: Eye

text: Most organisms with colour vision can detect ultraviolet light. This high energy light can be damaging to receptor cells. With a few exceptions (snakes, placental mammals), most organisms avoid these effects by having absorbent oil droplets around their cone cells. The alternative, developed by organisms that had lost these oil droplets in the course of evolution, is to make the lens impervious to UV light—this precludes the possibility of any UV light being detected, as it does not even reach the retina.


title: Eye

text: The retina contains two major types of light-sensitive photoreceptor cells used for vision: the rods and the cones.


title: Eye

text: Rods cannot distinguish colours, but are responsible for low-light (scotopic) monochrome (black-and-white) vision; they work well in dim light as they contain a pigment, rhodopsin (visual purple), which is sensitive at low light intensity, but saturates at higher (photopic) intensities. Rods are distributed throughout the retina but there are none at the fovea and none at the blind spot. Rod density is greater in the peripheral retina than in the central retina.


title: Eye

text: Cones are responsible for colour vision. They require brighter light to function than rods require. In humans, there are three types of cones, maximally sensitive to long-wavelength, medium-wavelength, and short-wavelength light (often referred to as red, green, and blue, respectively, though the sensitivity peaks are not actually at these colours). The colour seen is the combined effect of stimuli to, and responses from, these three types of cone cells. Cones are mostly concentrated in and near the fovea. Only a few are present at the sides of the retina. Objects are seen most sharply in focus when their images fall on the fovea, as when one looks at an object directly. Cone cells and rods are connected through intermediate cells in the retina to nerve fibres of the optic nerve. When rods and cones are stimulated by light, they connect through adjoining cells within the retina to send an electrical signal to the optic nerve fibres. The optic nerves send off impulses through these fibres to the brain.


title: Eye

text: The pigment molecules used in the eye are various, but can be used to define the evolutionary distance between different groups, and can also be an aid in determining which are closely related—although problems of convergence do exist.


title: Eye

text: Opsins are the pigments involved in photoreception. Other pigments, such as melanin, are used to shield the photoreceptor cells from light leaking in from the sides.


title: Eye

text: The opsin protein group evolved long before the last common ancestor of animals, and has continued to diversify since.


title: Eye

text: There are two types of opsin involved in vision; c-opsins, which are associated with ciliary-type photoreceptor cells, and r-opsins, associated with rhabdomeric photoreceptor cells. The eyes of vertebrates usually contain ciliary cells with c-opsins, and (bilaterian) invertebrates have rhabdomeric cells in the eye with r-opsins. However, some "ganglion" cells of vertebrates express r-opsins, suggesting that their ancestors used this pigment in vision, and that remnants survive in the eyes. Likewise, c-opsins have been found to be expressed in the "brain" of some invertebrates. They may have been expressed in ciliary cells of larval eyes, which were subsequently resorbed into the brain on metamorphosis to the adult form. C-opsins are also found in some derived bilaterian-invertebrate eyes, such as the pallial eyes of the bivalve molluscs; however, the lateral eyes (which were presumably the ancestral type for this group, if eyes evolved once there) always use r-opsins. Cnidaria, which are an outgroup to the taxa mentioned above, express c-opsins—but r-opsins are yet to be found in this group. Incidentally, the melanin produced in the cnidaria is produced in the same fashion as that in vertebrates, suggesting the common descent of this pigment.


title: Grumman F6F Hellcat

text: The Grumman F6F Hellcat is an American carrier-based fighter aircraft of World War II. Designed to replace the earlier F4F Wildcat and to counter the Japanese Mitsubishi A6M Zero, it was the United States Navy's dominant fighter in the second half of the Pacific War. In gaining that role, it prevailed over its faster competitor, the Vought F4U Corsair, which initially had problems with visibility and carrier landings.


title: Grumman F6F Hellcat

text: Powered by a Pratt & Whitney R-2800 Double Wasp, the same powerplant used for both the Corsair and the United States Army Air Forces (USAAF) Republic P-47 Thunderbolt fighters, the F6F was an entirely new design, but it still resembled the Wildcat in many ways. Some military observers tagged the Hellcat as the "Wildcat's big brother".


title: Grumman F6F Hellcat

text: The F6F made its combat debut in September 1943. It subsequently established itself as a rugged, well-designed carrier fighter, which was able to outperform the A6M Zero and help secure air superiority over the Pacific theater. In total, 12,275 were built in just over two years.


title: Grumman F6F Hellcat

text: Hellcats were credited with destroying a total of 5,223 enemy aircraft while in service with the U.S. Navy, U.S. Marine Corps, and Royal Navy Fleet Air Arm (FAA). This was more than any other Allied naval aircraft. After the war, Hellcats were phased out of front-line service in the US, but radar-equipped F6F-5Ns remained in service as late as 1954 as night fighters.


title: Grumman F6F Hellcat

text: Grumman had been working on a successor to the F4F Wildcat since 1938, and the contract for the prototype XF6F-1 was signed on 30 June 1941. The aircraft was originally designed to use the Wright R-2600 Twin Cyclone two-row, 14-cylinder radial engine of (the same engine used with Grumman's then-new torpedo bomber under development), driving a three-bladed Curtiss Electric propeller. Instead of the Wildcat's narrow-track, hand-cranked, main landing gear retracting into the fuselage inherited from the F3F ( a design from the 1930s Grumman FF-1 fighter biplane), the Hellcat had wide-set, hydraulically actuated landing-gear struts that rotated through 90° while retracting backwards into the wings, but with full wheel doors fitted to the struts that covered the entire strut and the upper half of the main wheel when retracted, and twisted with the main gear struts through 90° during retraction. The wing was mounted lower on the fuselage and was able to be hydraulically or manually folded, with each panel outboard of the undercarriage bay folding backwards from pivoting on a specially oriented, Grumman-patented "Sto-Wing" diagonal axis pivoting system much like the earlier F4F, with a folded stowage position parallel to the fuselage with the leading edges pointing diagonally down.


title: Grumman F6F Hellcat

text: Throughout early 1942, Leroy Grumman, along with his chief designers Jake Swirbul and Bill Schwendler, worked closely with the U.S. Navy's Bureau of Aeronautics (BuAer) and experienced F4F pilots, to develop the new fighter in such a way that it could counter the Zero's strengths and help gain air dominance in the Pacific Theater of Operations. On 22 April 1942, Lieutenant Commander Butch O'Hare toured the Grumman Aircraft company and spoke with Grumman engineers, analyzing the performance of the F4F Wildcat against the Mitsubishi A6M Zero in aerial combat. BuAer's Lt Cdr A. M. Jackson directed Grumman's designers to mount the cockpit higher in the fuselage. In addition, the forward fuselage sloped down slightly to the engine cowling, giving the Hellcat's pilot good visibility.


title: Grumman F6F Hellcat

text: Based on combat accounts of encounters between the F4F Wildcat and A6M Zero, on 26 April 1942, BuAer directed Grumman to install the more-powerful, 18-cylinder Pratt & Whitney R-2800 Double Wasp radial engine – which was already in use with Chance Vought's Corsair since 1940 – in the second XF6F-1 prototype. Grumman complied by redesigning and strengthening the F6F airframe to incorporate the R-2800-10, driving a three-bladed Hamilton Standard propeller. With this combination, Grumman estimated the XF6F-3s performance would increase by 25% over that of the XF6F-1. The Cyclone-powered XF6F-1 (02981) first flew on 26 June 1942, followed by the first Double Wasp-equipped aircraft, the XF6F-3' (02982), which first flew on 30 July 1942. The first production F6F-3, powered by an R-2800-10, flew on 3 October 1942, with the type reaching operational readiness with VF-9 on in February 1943.


title: Grumman F6F Hellcat

text: The F6F series was designed to take damage and get the pilot safely back to base. A bullet-resistant windshield was used and a total of of cockpit armor was fitted, along with armor around the oil tank and oil cooler. A self-sealing fuel tank was fitted in the fuselage. Standard armament on the F6F-3 consisted of six .50 in (12.7 mm) M2/AN Browning air-cooled machine guns with 400 rounds per gun. A center-section hardpoint under the fuselage could carry a single disposable drop tank, while later aircraft had single bomb racks installed under each wing, inboard of the undercarriage bays; with these and the center-section hard point, late-model F6F-3s could carry a total bomb load in excess of . Six High Velocity Aircraft Rockets (HVARs) could be carried – three under each wing on "zero-length" launchers.


title: Grumman F6F Hellcat

text: Two night-fighter subvariants of the F6F-3 were developed; the 18 F6F-3Es were converted from standard-3s and featured the AN/APS-4 10 GHz frequency radar in a pod mounted on a rack beneath the right wing, with a small radar scope fitted in the middle of the main instrument panel and radar operating controls installed on the port side of the cockpit. The later F6F-3N, first flown in July 1943, was fitted with the AN/APS-6 radar in the fuselage, with the antenna dish in a bulbous fairing mounted on the leading edge of the outer right wing as a development of the AN/APS-4; about 200 F6F-3Ns were built. Hellcat night fighters claimed their first victories in November 1943. In total, 4,402 F6F-3s were built through until April 1944, when production was changed to the F6F-5.


title: Grumman F6F Hellcat

text: The F6F-5 featured several improvements, including a more powerful R-2800-10W engine employing a water-injection system and housed in a slightly more streamlined engine cowling, spring-loaded control tabs on the ailerons, and an improved, clear-view windscreen, with a flat armored-glass front panel replacing the F6F-3's curved plexiglass panel and internal armor glass screen. In addition, the rear fuselage and tail units were strengthened, and apart from some early production aircraft, most of the F6F-5s built were painted in an overall gloss sea-blue finish. After the first few F6F-5s were built, the small windows behind the main canopy were deleted. The F6F-5N night-fighter variant was fitted with an AN/APS-6 radar in a fairing on the outer-starboard wing. A few standard F6F-5s were also fitted with camera equipment for reconnaissance duties as the F6F-5P. While all F6F-5s were capable of carrying an armament mix of one 20-mm (.79-in) M2 cannon in each of the inboard gun bays (220 rounds per gun), along with two pairs of .50-in (12.7-mm) machine guns (each with 400 rounds per gun), this configuration was only used on later F6F-5N night fighters. The F6F-5 was the most common F6F variant, with 7,870 being built.


title: Grumman F6F Hellcat

text: Other prototypes in the F6F series included the XF6F-4 (02981, a conversion of the XF6F-1 powered by an R-2800-27 and armed with four 20-mm M2 cannon), which first flew on 3 October 1942 as the prototype for the projected F6F-4'. This version never entered production and 02981 was converted to an F6F-3 production aircraft. Another experimental prototype was the XF6F-2' (66244), an F6F-3 converted to use a Wright R-2600-15, fitted with a Birman-manufactured mixed-flow turbocharger, which was later replaced by a Pratt & Whitney R-2800-21, also fitted with a Birman turbocharger. The turbochargers proved to be unreliable on both engines, while performance improvements were marginal. As with the XF6F-4, 66244 was soon converted back to a standard F6F-3. Two XF6F-6s (70188 and 70913) were converted from F6F-5s and used the 18-cylinder Pratt and Whitney R-2800-18W two-stage supercharged radial engine with water injection and driving a Hamilton-Standard four-bladed propeller. The XF6F-6s were the fastest version of the Hellcat series with a top speed of , but the war ended before this variant could be mass-produced.


title: Grumman F6F Hellcat

text: The last Hellcat rolled out in November 1945, the total production being 12,275, of which 11,000 had been built in just two years. This high production rate was credited to the sound original design, which required little modification once production was under way.


title: Grumman F6F Hellcat

text: The U.S. Navy much preferred the more docile flight qualities of the F6F compared with the Vought F4U Corsair, despite the superior speed of the Corsair. This preference was especially noted during carrier landings, a critical success requirement for the Navy. The Corsair was thus released by the Navy to the Marine Corps, which without the need to worry about carrier landings, used the Corsair to immense effect in land-based sorties. The Hellcat remained the standard USN carrier-borne fighter until the F4U series was finally cleared for U.S. carrier operations in late 1944 (the carrier landing issues had by now been tackled largely due to use of Corsair by the Royal Navy Fleet Air Arm, which started in 1943). In addition to its good flight qualities, the Hellcat was easy to maintain and had an airframe tough enough to withstand the rigors of routine carrier operations. Like the Wildcat, the Hellcat was designed for ease of manufacture and ability to withstand significant damage.


title: Grumman F6F Hellcat

text: The Hellcat first saw action against the Japanese on 1 September 1943, when fighters off shot down a Kawanishi H8K "Emily" flying boat. Soon after, on 23 and 24 November, Hellcats engaged Japanese aircraft over Tarawa, shooting down a claimed 30 Mitsubishi Zeros for the loss of one F6F. Over Rabaul, New Britain, on 11 November 1943, Hellcats and F4U Corsairs were engaged in day-long fights with many Japanese aircraft including A6M Zeros, claiming nearly 50 aircraft.


title: Grumman F6F Hellcat

text: When trials were flown against a captured A6M5 model Zero, they showed that the Hellcat was faster at all altitudes. The F6F out-climbed the Zero marginally above and rolled faster at speeds above . The Japanese fighter could out-turn its American opponent with ease at low speed and enjoyed a slightly better rate of climb below . The trials report concluded:


title: Grumman F6F Hellcat

text: Hellcats were the major U.S. Navy fighter type involved in the Battle of the Philippine Sea, where so many Japanese aircraft were shot down that Navy aircrews nicknamed the battle the "Great Marianas Turkey Shoot". The F6F accounted for 75% of all aerial victories recorded by the U.S. Navy in the Pacific. Radar-equipped Hellcat night-fighter squadrons appeared in early 1944.


title: Grumman F6F Hellcat

text: A formidable opponent for the Hellcat was the Kawanishi N1K, but it was produced too late and in insufficient numbers to affect the outcome of the war.


title: Grumman F6F Hellcat

text: U.S. Navy and Marine F6F pilots flew 66,530 combat sorties and claimed 5,163 kills (56% of all U.S. Navy/Marine air victories of the war) at a recorded cost of 270 Hellcats in aerial combat (an overall kill-to-loss ratio of 19:1 based on claimed kills). Claimed victories were often highly exaggerated during the war. Even so, the aircraft performed well against the best Japanese opponents with a claimed 13:1 kill ratio against the A6M Zero, 9.5:1 against the Nakajima Ki-84, and 3.7:1 against the Mitsubishi J2M during the last year of the war. The F6F became the prime ace-maker aircraft in the American inventory, with 305 Hellcat aces. The U.S. successes were not just attributed to superior aircraft; from 1942 onwards, they faced increasingly inexperienced Japanese aviators and had the advantage of increasing numerical superiority. In the ground-attack role, Hellcats dropped 6,503 tons (5,899 tonnes) of bombs.


title: Grumman F6F Hellcat

text: The U.S. Navy's all-time leading ace, Captain David McCampbell, scored all his 34 victories in the Hellcat. He once described the F6F as "... an outstanding fighter plane. It performed well, was easy to fly, and was a stable gun platform, but what I really remember most was that it was rugged and easy to maintain."


title: Grumman F6F Hellcat

text: During the course of World War II, 2,462 F6F Hellcats were lost to all causes – 270 in aerial combat, 553 to antiaircraft ground and shipboard fire, and 341 due to operational causes. Of the total figure, 1,298 were destroyed in training and ferry operations, normally outside of the combat zones.


title: Grumman F6F Hellcat

text: Hamilton McWhorter III, a Navy aviator and a flying ace of World War II, was credited with shooting down 12 Japanese aircraft. He was the first U.S. Navy aviator to become an ace while flying the Grumman F6F Hellcat and the first Navy carrier pilot to achieve double ace status.


title: Grumman F6F Hellcat

text: Arthur Van Haren, Jr., a Navy combat Hellcat ace of WWII from Arizona, was credited with shooting down 9 Japanese planes. He was awarded a DFC, and a Gold Star in lieu of a second DFC. In 2012, Van Haren, Jr. was inducted into the Arizona Aviation Hall of Fame.


title: Grumman F6F Hellcat

text: The British Fleet Air Arm (FAA) received 1,263 F6Fs under the Lend-Lease Act; initially, it was known as the Grumman Gannet Mark I. The name Hellcat replaced it in early 1943 for the sake of simplicity, the Royal Navy at that time adopting the use of the existing American naval names for all the U.S.-made aircraft supplied to it, with the F6F-3 being designated Hellcat F Mk. I, the F6F-5, the Hellcat F Mk. II and the F6F-5N, the Hellcat NF Mk. II. They saw action off Norway, in the Mediterranean, and in the Far East. Several were fitted with photographic reconnaissance equipment similar to the F6F-5P, receiving the designation Hellcat FR Mk. II. The Pacific War being primarily a naval war, the FAA Hellcats primarily faced land-based aircraft in the European and Mediterranean theaters, so experienced far fewer opportunities for air-to-air combat than their USN/Marines counterparts; nevertheless, they claimed a total of 52 enemy aircraft kills during 18 aerial combats from May 1944 to July 1945. 1844 Naval Air Squadron, on board of the British Pacific Fleet was the highest-scoring unit, with 32.5 kills.


title: Grumman F6F Hellcat

text: FAA Hellcats, as with other Lend-Lease aircraft, were rapidly replaced by British aircraft after the end of the war, with only two of the 12 squadrons equipped with the Hellcat at VJ-Day still retaining Hellcats by the end of 1945. These two squadrons were disbanded in 1946.


title: Grumman F6F Hellcat

text: After the war, the Hellcat was succeeded by the F8F Bearcat, which was smaller, more powerful (powered by uprated Double Wasp radials) and more maneuverable, but entered service too late to see combat in World War II.


title: Grumman F6F Hellcat

text: The Hellcat was used for second-line USN duties, including training and Naval Reserve squadrons, and a handful were converted to target drones. In late 1952, Guided Missile Unit 90 used F6F-5K drones, each carrying a bomb, to attack bridges in Korea. Flying from , the Hellcat drones were radio controlled from an escorting AD Skyraider.


title: Grumman F6F Hellcat

text: The F6F-5 was the first aircraft used by the U.S. Navy's Blue Angels official flight demonstration team at its formation in 1946.


title: Grumman F6F Hellcat

text: The French Navy (Aéronavale) was equipped with F6F-5 Hellcats and used them in combat in Indochina. These were painted in Gloss Sea Blue, similar to post-World War II US Navy aircraft until about 1955, but had a modified French roundel with an image of an anchor. The French Air Force also used the Hellcat in Indochina from 1950 to 1952. The plane equipped four squadrons (including the Normandie-Niemen squadron of WWII fame) before these units transitioned to the F8F Bearcat.


title: Grumman F6F Hellcat

text: A relatively large number of Grumman F6Fs survive to this day, either in museums or in flyable condition. In order of Bu.No. they are:


title: Fire Emblem: Three Houses

text: "Three Houses" is set on the continent of Fódlan, divided between three ruling powers currently at peace. These nations are connected through the Garreg Mach Monastery, which houses a church and an officer's school for students from each nation. Taking the role of Byleth, a former mercenary with a mysterious past and the academy's newest professor, the player must choose a class to lead and guide their students through a series of battles. The game maintains the turn-based tactical gameplay of the previous "Fire Emblem" titles, while incorporating social simulation and time management elements.


title: Fire Emblem: Three Houses

text: The game's production was challenging for Intelligent Systems, who attributed its success and timely release to Koei Tecmo, who had previously partnered with the company for "Fire Emblem Warriors". The staff wanted something entirely new for the franchise's debut on high-definition home consoles, birthing the school life mechanics and expansions to battle. Chinatsu Kurahana was responsible for creating the character designs and illustrations. The game's school system and a time skip later in the story took inspiration from the fourth installment, "".


title: Fire Emblem: Three Houses

text: The game received generally favorable reviews, with critics praising the integration of the school system and battalion mechanics, narrative, characters, soundtrack, and replay value. Minor criticisms were directed at the game's easier difficulty compared to past installments as well as some visual and technical problems. The game would go on to win Best Strategy Game and the Player's Voice Award at The Game Awards 2019. As of December 2021, the game has sold 3.82 million copies worldwide, making it the single best-selling game in the franchise. A "Warriors"-style spin-off, entitled "", was released for the Nintendo Switch on June 24, 2022.


title: Fire Emblem: Three Houses

text: "Fire Emblem: Three Houses" is a tactical role-playing game in which players control a player character whose gender and name are chosen at the beginning of the game. During the opening hours, the player character is asked to teach at the Garreg Mach Monastery, which acts as a hub for game activities. Choosing a particular house to teach impacts the narrative from that point on. The player's time is divided between story-based battles that advance the main narrative, and periods in Garreg Mach where they interact with students and staff members there. While the opening half of the game focuses on this school system, the story skips ahead five years and focuses more on battle, with the player being locked to the house they chose during the opening half.


title: Fire Emblem: Three Houses

text: During the periods between storyline battles, the player has a set number of days marked on a calendar, which can be used for a variety of activities from teaching classes and field exercises to planting seeds in the greenhouse and fishing in the pond. The player also has free time events, where they can socially interact with students and build up relationships with them. Building a relationship is done through Support actions, with actions and dialogue choices impacting a character's Support level. If the relationship is strong enough, this can lead to the two marrying after a story-based time skip event. By raising particular attributes through actions in battle and within the Monastery, the player can recruit students from other houses, alongside other characters. Each action during the academy section costs a set number of time points, with a limited number of time points available each day and more activities than can be covered by the points available. The player must choose which events to trigger, losing access to others in consequence. Network play and Amiibo functionality are also supported, with network play allowing players to passively visit other players' monasteries online, and compatible Amiibo figures to be scanned for additional materials and bonus music tracks for scanning "Fire Emblem"-specific Amiibo.


title: Fire Emblem: Three Houses

text: As with other "Fire Emblem" games, "Three Houses" uses a turn-based battle system; players take control of a set number of unique units. They move across a grid, transitioning from a top-down perspective to a third-person view when a battle is triggered. A new feature to the series allows player to hire Battalions, additional troops that can support a chosen unit. Battalions have passive abilities which grant character buffs to the lead unit, and can perform special moves called Gambits, which can range from healing multiple units to stunning powerful enemies. Players can also zoom in on the battlefield to assess individual battalions. As with other entries, there is a "Classic" mode where characters who fall in battle are subjected to permanent death, and a "Casual" mode where fallen characters are revived after each battle. After a certain point in the story, players can rewind and undo a set amount of turn actions per battle using the "Divine Pulse" ability.


title: Fire Emblem: Three Houses

text: Every unit is assigned a character class, which can be customized. While characters have starting abilities which naturally grant them a class, they can be taught additional skills which alter their class. Class changes are available upon a student's "certification" during the school segments, with certain prerequisites recommended to have a higher chance at passing the corresponding certification exam. Prior to starting a school week, lesson plans can be put into place to individually manage a unit's growth, build Support between two classmates by engaging them in group assignments, or simply instruct the class automatically with a passive "auto-instruct" feature. Rather than the previously-established Weapon Triangle of earlier "Fire Emblem" games, different units have weapon-based skills called Combat Arts they can be taught during the school segments. Weapons have a set number of uses before they degrade and have their stats reduced. Combat Arts are learned by becoming proficient in a type of weapon; they deal higher damage than standard attacks in exchange for a large chunk of a weapon's durability.


title: Fire Emblem: Three Houses

text: "Three Houses" takes place on the continent of Fódlan. The landmass is divided into three rival nations who are now at peace: the Adrestian Empire to the south and west, the Holy Kingdom of Faerghus to the north, and the Leicester Alliance to the east. The Church of Seiros, based at Garreg Mach Monastery at the continent's center, is the region's dominant religion and is an influential power in Fódlan in its own right. In ancient history, a war raged between the Church's titular founder Seiros and the "King of Liberation" Nemesis, an era which also saw the establishment of the Empire by Seiros. In the thousand years since then, the Kingdom split away from the Empire, then the Alliance declared its independence from both powers. A prolonged conflict ensued, with the Church being responsible for keeping peace. The nobility of Fódlan frequently bear Crests, sigils passed down through families that grant magical powers. Bearing a crest greatly influences dynastic politics, with nobles inheriting Crests valued far above those who lack them. Those who have Crests can also wield powerful artifacts called Hero's Relics. The series's titular "Fire Emblem" appears as the "Crest of Flames", the Crest associated with the Progenitor God.


title: Fire Emblem: Three Houses

text: Players take on the role of the main character, called Byleth by default and who can be either male or female. A mercenary by trade, they become enrolled in the Officers Academy of Garreg Mach Monastery as a teacher. During their journey Byleth is aided by Sothis, a strange and initially-amnesiac girl who appears in their dreams and can only be heard by them. At Garreg Mach Monastery, Byleth chooses one of the three school houses, each aligned to a different nation of Fódlan. They are the Black Eagles led by Edelgard, imperial princess and heir to the Adrestian throne; the Blue Lions, commanded by Prince Dimitri of the Kingdom; and the Golden Deer led by Claude, heir to the Alliance's leading family. The Monastery's staff includes those who directly work for the Church, some of whom are recruitable by the player. Other characters include Jeralt, father of Byleth, and Rhea, archbishop of the Church.


title: Fire Emblem: Three Houses

text: One night, Byleth and Jeralt rescue three young nobles, Edelgard, Dimitri, and Claude from bandits, greatly impressing them. During the attack, Byleth is saved by the mysterious Sothis, who remains within them. Jeralt and Byleth are summoned to Garreg Mach Monastery, the home of the Church of Seiros, Fódlan's dominant religion. Jeralt reluctantly rejoins the Church's military arm, the Knights of Seiros, while Byleth is made a professor of the monastery's Officers Academy. Jeralt privately warns Byleth not to trust the Church's archbishop, Rhea. Byleth is then given the choice of leading one of the academy's three houses: the Black Eagles, the Blue Lions, or the Golden Deer, each populated by students from the Empire, Kingdom, and Alliance respectively. Byleth assumes their duties as teacher for their chosen house, training their students and leading them in battles on behalf of the Knights of Seiros. Byleth and their students discover frightening hints on the nature of Relics and Crests, such as a Relic thief transforming into a monster. Various conspiracies meddle with the monastery and plot against the Church: masked warriors called the Flame Emperor and the Death Knight, the Western branch of the Church, and a hostile cult known as "those who slither in the dark". Byleth thwarts an attempt to steal a powerful Hero's Relic, the Sword of the Creator. Unexpectedly, the Sword activates when Byleth holds it, and Rhea allows them to keep it.


title: Fire Emblem: Three Houses

text: Byleth reunites with Claude, and they rally their students and the remnants of the Church to stand against the Empire. Gathering allies and support, Byleth and Claude invade the Empire. As they confront Emperor Edelgard and her forces, a Kingdom army led by Dimitri also arrives, resulting in a massive battle. Edelgard is forced to retreat while Dimitri is killed. Byleth and Claude press on towards a strategic Empire fort, and receive aid from the foreign nation of Alymra. Claude admits he secretly opened relations with Almyra, and announces his desire to open Fódlan's borders to the outside world and end the continent's isolationism. Byleth and Claude attack the Empire capital, where they defeat and kill Edelgard. Byleth and Claude learn "those who slither in the dark" have been manipulating both the current war and the original war a millennium before. Claude's army defeats the cult in their secret underground city Shambhala. Their leader attempts to destroy them with a rain of missiles, but Rhea intercepts the missiles in her dragon form. Meanwhile, Nemesis is awakened from his tomb by the cult; he and his Ten Elites were a band of thieves who took power from Sothis and her dragon kin after they were slain by the cult in the ancient era. This power was the source of the nobility's crests. Byleth and Claude destroy Nemesis and his undead army. In the aftermath, Fódlan is united under Byleth's rule as they and Claude open its borders and start relations with foreign nations.


title: Fire Emblem: Three Houses

text: Byleth reunites with Dimitri, who has been ousted from the Kingdom due to a coup from pro-Empire nobles. Dimitri has become bitter, disillusioned, and unstable as he is haunted by visions of his deceased family and driven to kill Edelgard at any cost. Byleth's students and the remnants of the Church ally with Dimitri despite his erratic behavior. Dimitri eventually forces a massive battle between his own army, the Empire, and the Alliance, resulting in heavy losses on all sides. One of Dimitri's trusted vassals sacrifices himself to protect him from an assassin, which combined with Byleth's guidance causes Dimitri to abandon his desire for revenge. After securing his own lands, Dimitri rescues Claude from imperial forces. Claude dissolves the Alliance and cedes its lands to Dimitri before departing Fódlan. Dimitri then marches for the Empire capital itself. Wanting to make peace with Edelgard, Dimitri arranges a meeting with her and suggest they join forces to realize their goals; Edelgard refuses. Dimitri is able to defeat Edelgard and once again offers her mercy, but is forced to kill her when she attempts to attack him. In the aftermath, Fódlan is united under the Kingdom with Dimitri as its ruler, while Byleth becomes the new archbishop of the Church when Rhea steps down.


title: Fire Emblem: Three Houses

text: If Byleth sides with Edelgard on this route, they reunite with their students and find that the Kingdom has allied with the Church while the Alliance remains nominally neutral. Edelgard and Byleth attack and seize the Alliance capital and eliminate Claude from the war, either through killing or exiling him. They then advance into the Kingdom, taking a vital fortress. In retribution for Edelgard interfering with their schemes, "those who slither in the dark" arrange for the fortress to be destroyed. Edelgard keeps the truth a secret and tells the others that the fortress was destroyed by Church weaponry. Edelgard continues to lead her armies to the Kingdom's capital. Dimitri meets Edelgard in battle, but is defeated and killed. The Kingdom army is routed and Rhea withdraws to the Kingdom capital with her Knights. In her madness, Rhea sets fire to the city, forcing Edelgard to attack to put a stop to her. Byleth and Edelgard are able to kill Rhea. Byleth nearly dies, but Sothis's Crest Stone embedded in their heart dissolves, reviving them. In the aftermath, Edelgard unites all of Fódlan under the Empire and abolishes both the Church and the nobility.


title: Fire Emblem: Three Houses

text: If Byleth sides against Edelgard after having joined the Black Eagles, a similar scenario to the Golden Deer route plays out with Byleth allied with Church remnants and the Black Eagle students against the Empire. After defeating Edelgard in the Empire's capital and "those who slither in the dark" in Shambhala, Byleth learns the full truth of their origins from Rhea, and is then forced to defeat her after she is driven berserk due to wounds sustained in Shambhala. Fódlan is subsequently unified under the Church with Byleth as its new leader.


title: Fire Emblem: Three Houses

text: Byleth pursues an intruder into a hidden underground complex called Abyss, discovering a secret house called the Ashen Wolves; originally hidden through a secret truce, mercenaries have begun raiding Abyss. Byleth and the students agree to help defend Abyss. Aelfric, the Church's liaison to Abyss, warns Byleth that factions within the Church would like to see Abyss purged. Aelfric theorizes that the mercenaries are looking for the Chalice of Beginnings, a key object in a ritual attempted during Garreg Mach's early days with the aim of resurrecting Sothis. Aelfric is captured and ransomed for the Chalice, which Rhea reluctantly agrees to hand over believing the ritual lost. The Ashen Wolves also privately admit to Byleth that they are descendants of the four who performed the ritual, ordered by the Church to keep their bloodlines secret. Aelfric is revealed to be the mastermind, capturing the Ashen Wolves and preparing to use the Chalice to resurrect Byleth's mother Sitri, for whom he held a secret love. Byleth rescues the Ashen Wolves, and when he attempts the ritual anyway Aelfric is transformed into a monster and killed. The Ashen Wolves are disbanded and allowed to leave Garreg Mach, with the four members to return to help each other and Byleth if needed.


title: Fire Emblem: Three Houses

text: Following the unexpected success of "Fire Emblem Awakening" for the Nintendo 3DS—which helped save the series from cancellation after flagging sales of earlier entries—the "Fire Emblem" series gained renewed commercial value and prompted developer Intelligent Systems and publisher Nintendo to bring the series back to home consoles for the first time since "" in 2007. Concept development for "Three Houses" began in 2015 following the completion of "Fire Emblem Fates" for the 3DS. The team originally planned for "Three Houses" to be another 3DS title. This was scrapped when production began on "", resulting in "Three Houses" being briefly put on hold. When the team learned of the Nintendo Switch, they decided to make the game for home consoles. The team wanted the game to be the biggest and best in the series, and due to it being for home consoles they felt they could not make it alone. With this in mind, they decided to bring in help from Koei Tecmo. At this time, Intelligent Systems and Koei Tecmo were collaborating on the spin-off game "Fire Emblem Warriors". After consultation, Koei Tecmo's internal team led by Kou Shibusawa was recommended to them. The biggest challenge for the developers was bringing the series to a high-definition console, a first for the series. Koei Tecmo was deeply concerned in this aspect of development. Full production began in 2017 when "Shadows of Valentia" was finished, with Toshiyuki Kusakihara and Genki Yokota—respective directors for Intelligent Systems and Nintendo EPD— returning to direct the game.


title: Fire Emblem: Three Houses

text: The game's scenario was written by Koei Tecmo's Yuki Ikeno, Ryohei Hayashi and Mari Okamoto. All three previously worked on the scenario for "Warriors" and were brought onto the development of "Three Houses" to help assist Intelligent Systems in writing the social segments of the game. The narrative was written in the vein of a dark fantasy, with the mature aspects of the narrative showing through the conflict between the three factions. The first storyline conceived was the Black Eagle House, with Kusakihara and the other scenario writers building and expanding on the world and characters from that starting point. Voice recording took three months; Kusakihara estimated the amount of voice acting for the Japanese version as five times that of "Fire Emblem Echoes". Two key parts of the game, the school sections and a time skip late in the story, were directly inspired by the 1996 entry ""; the narrative in "Three Houses" of characters who were friends in their youth coming into conflict during their older years was almost directly lifted from "Genealogy of the Holy War". Kusakihara also admitted influence from the Chinese novel "Romance of the Three Kingdoms" and Koei Tecmo's adaptation of it in the "Dynasty Warriors" game series; this came about after Intelligent Systems looked at the narrative and world designs used by the Kou Shibusawa unit. The game's chosen subtitle in Japan was ""Fūkasetsugetsu"", a "yojijukugo" of the four seasons to represent the narrative's four branching paths. As it translated awkwardly, it was replaced by the subtitle ""Three Houses"" in English.


title: Fire Emblem: Three Houses

text: While Intelligent Systems staff handled the weapon and world design, freelance illustrators were brought in for other parts. The team wanted a new artistic image for the series. Character designs and illustrations were handled by Chinatsu Kurahana, known for "Uta no Prince-sama" and "Tokyo Twilight Ghost Hunters" and who was the main character designer of the game. Kazuma Koda, who had worked on both "Bayonetta 2" and "" as a concept artist, was contracted to provide concept art for the game. Kurahana was in talks with Intelligent Systems prior to development, and the final decision was made as Kusakihara felt she could best illustrate the "glamorous, aristocratic society" portrayed in the game. Her influence was particularly noted in the hairstyles of characters, which differed from those seen in earlier "Fire Emblem" leads. The anime cutscenes were directed by Takashi Sano and produced by Sanzigen, noted for their cel-shaded 3D CGI animation. The music was composed by "Fates" composers Takeru Kanazaki and Hiroki Morishita, and "Awakening" composer Rei Kondoh.


title: Fire Emblem: Three Houses

text: Kusakihara and Yokota stated in an interview that "Three Houses" in its released form would have been difficult or impossible to make without Koei Tecmo's help. The directors particularly cited Koei Tecmo's experience developing large-scale battles for their "Dynasty Warriors" franchise. This experience allowed large numbers of characters to be shown on screen in battles for the first time in the series. While Koei Tecmo helped with much of the technical and programming side, Intelligent Systems still took the lead on design and other core aspects of development. The new school setting allowed the team to considerably expand the series' RPG mechanics beyond the typical tactical battles which had dominated the series up to that point. The social aspects went through multiple unsatisfactory builds before some team members suggested a calendar system and ability points. This version finally satisfied the team.


title: Fire Emblem: Three Houses

text: The Weapon Triangle, a recurring system for most of the series, was discarded due to it being a "stylized" system. The new weapon-based skill system was designed to be more realistic and increase player choice. Due to its status as the first home console entry in twelve years, the team were under pressure to create something new and exciting. This led to the creation of Battalions in battle and the teaching segments. Time limits were suggested by Kusakihara, who was inspired by Nintendo's "Pikmin" franchise. The skill growth system drew inspiration from "Zill O'll", a role-playing series developed by Koei. The team toyed with the idea of including child characters from romantic supports for the story's second half, a feature from "Genealogy of the Holy War" which they had used extensively in "Awakening" and "Fates". They soon decided against this, opting for a support experience based around character maturation and platonic relationships. While online features such as seen in the "My Castle" feature from "Fates" were considered, the Monastery was so expansive and its history deep enough that such customization and sharing options would be impractical to implement, so it was left out.


title: Fire Emblem: Three Houses

text: Nintendo first announced that a new mainline "Fire Emblem" game was in development for the Nintendo Switch in January 2017 during a Nintendo Direct focused on the series, with a projected release date in 2018. More information was revealed during Nintendo's E3 2018 presentation, showing gameplay and even the finalized title. However, it also confirmed that the release date would be pushed back into early 2019. In February 2019, the game was showcased in another Nintendo Direct displaying new gameplay and story details, including a second delay with the game's release date falling on July 26, 2019 and the confirmation of Koei Tecmo as the co-developer. Another story trailer was showcased at the E3 2019 Nintendo Direct presentation with additional gameplay being shown at Nintendo Treehouse Live later in the week.


title: Fire Emblem: Three Houses

text: In July, Nintendo revealed that the game would be receiving an Expansion Pass that would contain downloadable content for the game that would be released from the game's launch until April 2020. The first wave of DLC added a new "Maddening" difficulty mode, made to address concerns about the game's low level of challenge on "Hard" mode, as well as various cosmetic options. It also patched in a new voice actor for Byleth, replacing Chris Niosi with Zach Aguilar following Niosi's admissions of emotional and physical abuse. The admissions included violation of a non-disclosure agreement with Nintendo about his role as Byleth. Later waves of DLC added additional playable characters, additional actions within the monastery, and the "Cindered Shadows" storyline.


title: Fire Emblem: Three Houses

text: "Fire Emblem: Three Houses" has received "generally favorable" reviews holding an aggregate score of 89/100 on Metacritic, based on 102 reviews. According to the site, it is the fourth highest-scoring Switch game of 2019, and the highest-rated Switch exclusive.


title: Fire Emblem: Three Houses

text: The four reviewers for Japanese gaming magazine "Famitsu" all gave praise, with one giving it a perfect score of 10 and the others a 9. "Eurogamer"s Martin Robinson said that it "really is a game of two halves, but they come together to make one incredible whole." Kimberley Wallace, writing for "Game Informer", praised the game's ambition and willingness to take risks with the series formula, being surprised by how willing she was to begin a new game after finishing the campaign. Aron Garst of "GamesRadar" gave "Three Houses" a perfect score, praising how the game kept him invested in its characters, with his main criticism of the gameplay being its low difficulty.


title: Fire Emblem: Three Houses

text: "GameSpot"s Kallie Plagge did not like the need for multiple playthroughs to see the entire narrative, but was otherwise enthusiastic about the game's story and gameplay; she called it "the kind of game that's hard to put down, even when it's over". Brendan Graeber of "IGN" felt that its depth of characters and tactical options more than justified multiple playthroughs, particularly praising its narrative as being superior to that of "Fire Emblem Fates". "Nintendo World Report"s Daan Koopman said that, despite finding the finales of some acts disappointing, the overall narrative and gameplay kept him invested.


title: Fire Emblem: Three Houses

text: The scenario was met with praise, being cited as a mature and ambitious narrative with strong character interactions, with many lauding the difficult choices presented when picking a side in the first half of the campaign. The two interacting gameplay styles were also positively received, with many noting the social elements as a welcome tactical addition. The game's graphics saw a mixed response, with several websites faulting them as low-quality despite strong artistic design. The music and voice acting met with a strong positive response in both versions.


title: Fire Emblem: Three Houses

text: "Fire Emblem: Three Houses" was the best-selling game during its first week on retail sale in Japan, with 143,130 copies being sold. The game was also the best-selling physical game in the United Kingdom that same week, selling twice as much as its second place competitor "". SuperData Research estimated that "Three Houses" sold 800,000 digital copies through the Nintendo Switch eShop in its launch month of July 2019. In August 2019, the NPD Group shared the ranking of best-selling games for the month of July in the United States, and "Fire Emblem: Three Houses" was in second place counting only physical sales. As of March 2020, the game has sold 580k copies in Japan and 2.87 million copies worldwide, making it the single best-selling game in the "Fire Emblem" franchise. The 2022 CESA Games White Papers revealed that the game had sold 3.82 million copies, as of December 31, 2021.


title: Fire Emblem: Three Houses

text: The game won the award for "Best Switch Exclusive" and its People's Voice at the IGN Game of the Year Awards 2019, whereas its other nominations were for "Game of the Year" and "Best Strategy/Tactics Game".


title: Fire Emblem: Three Houses

text: Characters from "Three Houses" were added as playable units in the mobile game "Fire Emblem Heroes" shortly after the game's release. A costume based on "Three Houses" was included in the Nintendo Switch port of "Tokyo Mirage Sessions ♯FE". Byleth appears as a playable character in the 2018 crossover fighting game "Super Smash Bros. Ultimate", being released as downloadable content on January 28, 2020. Both male and female versions of Byleth are present as alternate costumes for the fighter, whose attacks are based around the use of four of the game's weapons. The Byleth DLC also includes Garreg Mach Monastery as a new stage, as well as a selection of eleven music tracks from "Three Houses". An Amiibo figure of Byleth was released on March 26, 2021. A "Three Houses"-inspired tea drinking minigame was included in the 2021 video game "" for Nintendo Switch.


title: Fire Emblem: Three Houses

text: In February 2022 during a Nintendo Direct presentation, Nintendo announced a spin-off of "Three Houses" for the Nintendo Switch entitled "", a hack and slash game in the style of Koei Tecmo's "Dynasty Warriors" series and a successor to 2017's "Fire Emblem Warriors", which was released on June 24, 2022. It is set in the same universe as "Fire Emblem: Three Houses" along with the same cast of characters, but features an alternative story where Byleth does not come to teach at the monastery, along with a completely new protagonist and scenarios.


title: New France

text: New France () was the area colonized by France in North America, beginning with the exploration of the Gulf of Saint Lawrence by Jacques Cartier in 1534 and ending with the cession of New France to Great Britain and Spain in 1763 under the Treaty of Paris.


title: New France

text: The vast territory of "New France" consisted of five colonies at its peak in 1712, each with its own administration: Canada, the most developed colony, was divided into the districts of Québec, Trois-Rivières, and Montréal; Hudson Bay; Acadie in the northeast; Plaisance on the island of Newfoundland; and Louisiane. It extended from Newfoundland to the Canadian Prairies and from Hudson Bay to the Gulf of Mexico, including all the Great Lakes of North America.


title: New France

text: In the 16th century, the lands were used primarily to draw from the wealth of natural resources such as furs through trade with the various indigenous peoples. In the seventeenth century, successful settlements began in Acadia and in Quebec. In the 1713 Treaty of Utrecht, France ceded to Great Britain its claims over mainland Acadia, Hudson Bay, and Newfoundland. France established the colony of Île Royale on Cape Breton Island, where they built the Fortress of Louisbourg.


title: New France

text: The population rose slowly but steadily. In 1754, New France's population consisted of 10,000 Acadians, 55,000 "Canadiens", and about 4,000 settlers in upper and lower Louisiana; 69,000 in total. The British expelled the Acadians in the Great Upheaval from 1755 to 1764, which has been remembered on July 28 each year since 2003. Their descendants are dispersed in the Maritime provinces of Canada and in Maine and Louisiana, with small populations in Chéticamp, Nova Scotia and the Magdalen Islands. Some also went to France.


title: New France

text: After the Seven Years' War (which included the French and Indian War in America), France ceded the rest of New France to Great Britain and Spain in the Treaty of Paris of 1763 (except the islands of Saint Pierre and Miquelon). Britain acquired Canada, Acadia, and French Louisiana east of the Mississippi River, except for the Île d'Orléans, which was granted to Spain with the territory to the west. In 1800, Spain returned its portion of Louisiana to France under the secret Treaty of San Ildefonso, and Napoleon Bonaparte sold it to the United States in the Louisiana Purchase of 1803, permanently ending French colonial efforts on the American mainland.


title: New France

text: New France eventually became absorbed within the United States and Canada, with the only vestige of French rule being the tiny islands of Saint Pierre and Miquelon. In the United States, the legacy of New France includes numerous place names as well as small pockets of French-speaking communities.


title: New France

text: Around 1523, the Florentine navigator Giovanni da Verrazzano convinced King Francis I to commission an expedition to find a western route to Cathay (China). Late that year, Verrazzano set sail in Dieppe, crossing the Atlantic on a small caravel with 50 men. After exploring the coast of the present-day Carolinas early the following year, he headed north along the coast, eventually anchoring in the Narrows of New York Bay.


title: New France

text: The first European to visit the site of present-day New York, Verrazzano named it Nouvelle-Angoulême in honour of the king, the former count of Angoulême. Verrazzano's voyage convinced the king to seek to establish a colony in the newly discovered land. Verrazzano gave the names "Francesca" and "Nova Gallia" to that land between New Spain (Mexico) and English Newfoundland.


title: New France

text: In 1534, Jacques Cartier planted a cross in the Gaspé Peninsula and claimed the land in the name of King Francis I. It was the first province of New France. The first settlement of 400 people, Fort Charlesbourg-Royal (present-day Quebec City), was attempted in 1541 but lasted only two years.


title: New France

text: French fishing fleets continued to sail to the Atlantic coast and into the St. Lawrence River, making alliances with Canadian First Nations that became important once France began to occupy the land. French merchants soon realized the St. Lawrence region was full of valuable fur-bearing animals, especially the beaver, which were becoming rare in Europe. Eventually, the French crown decided to colonize the territory to secure and expand its influence in America.


title: New France

text: Another early French attempt at settlement in North America took place in 1564 at Fort Caroline, now Jacksonville, Florida. Intended as a haven for Huguenots, Caroline was founded under the leadership of René Goulaine de Laudonnière and Jean Ribault. It was sacked by the Spanish led by Pedro Menéndez de Avilés who slaughtered every Protestant there and then established the settlement of St. Augustine on 20 September 1565.


title: New France

text: Acadia and Canada (New France) were inhabited by indigenous nomadic Algonquian peoples and sedentary Iroquoian peoples. These lands were full of unexploited and valuable natural resources, which attracted all of Europe. By the 1580s, French trading companies had been set up, and ships were contracted to bring back furs. Much of what transpired between the indigenous population and their European visitors around that time is not known, for lack of historical records.


title: New France

text: Other attempts at establishing permanent settlements were also failures. In 1598, a French trading post was established on Sable Island, off the coast of Acadia, but was unsuccessful. In 1600, a trading post was established at Tadoussac, but only five settlers survived the winter.


title: New France

text: In 1604, a settlement was founded at Île-Saint-Croix on Baie François (Bay of Fundy), which was moved to Port-Royal in 1605. It was abandoned in 1607, re-established in 1610, and destroyed in 1613, after which settlers moved to other nearby locations, creating settlements that were collectively known as Acadia, and the settlers as Acadians.


title: New France

text: In 1608, King Henry IV sponsored Pierre Dugua, Sieur de Mons and Samuel de Champlain as founders of the city of Quebec with 28 men. This was the second permanent French settlement in the colony of Canada. Colonization was slow and difficult. Many settlers died early because of harsh weather and diseases. In 1630, there were only 103 colonists living in the settlement, but by 1640, the population had reached 355.


title: New France

text: Champlain allied himself with the Algonquin and Montagnais peoples in the area, who were at war with the Iroquois, as soon as possible. In 1609, Champlain and two French companions accompanied his Algonquin, Montagnais, and Huron allies south from the St. Lawrence Valley to Lake Champlain. He participated decisively in a battle against the Iroquois there, killing two Iroquois chiefs with the first shot of his arquebus. This military engagement against the Iroquois solidified Champlain's status with New France's Huron and Algonquin allies, enabling him to maintain bonds essential to New France's interests in the fur trade.


title: New France

text: Champlain also arranged to have young French men live with local indigenous people, to learn their language and customs and help the French adapt to life in North America. These "coureurs des bois" ("runners of the woods"), including Étienne Brûlé, extended French influence south and west to the Great Lakes and among the Huron tribes who lived there. Ultimately, for the better part of a century, the Iroquois and French clashed in a series of attacks and reprisals.


title: New France

text: During the first decades of the colony's existence, only a few hundred French people lived there, while the English colonies to the south were much more populous and wealthier. Cardinal Richelieu, adviser to Louis XIII, wished to make New France as significant as the English colonies. In 1627, Richelieu founded the Company of One Hundred Associates to invest in New France, promising land parcels to hundreds of new settlers and to turn Canada into an important mercantile and farming colony. He named Champlain as the Governor of New France and forbade non-Roman Catholics to live there. Consequently, any Protestant emigrants to New France were forced to convert to Catholicism, prompting many of them to relocate to the English colonies instead.


title: New France

text: The Roman Catholic Church, and missionaries such as the Recollets and the Jesuits, became firmly established in the territory. Richelieu also introduced the seigneurial system, a semi-feudal system of farming based on ribbon farms that remained a characteristic feature of the St. Lawrence valley until the 19th century. While Richelieu's efforts did little to increase the French presence in New France, they did pave the way for the success of later efforts.


title: New France

text: Simultaneously, the English colonies to the south began raiding the St. Lawrence Valley, also capturing and holding Quebec until 1632. Champlain returned to Canada that year and requested that Sieur de Laviolette found another trading post at Trois-Rivières, which Laviolette did in 1634. Champlain died in 1635.


title: New France

text: On 23 September 1646, under the command of Pierre LeGardeur, Le Cardinal arrived to Quebec with Jules (Gilles) Trottier II and his family. Le Cardinal, commissioned by the Communauté des Habitants, had arrived from La Rochelle, France. Communauté des Habitants at the time of Trottier traded fur primarily. On 4 July 1646, by Pierre Teuleron, sieur de Repentigny, granted Trottier land in La Rochelle to build and develop New France, under the authorization Jacques Le Neuf de la Poterie.


title: New France

text: In 1650, New France had seven hundred colonists and Montreal had only a few dozen settlers. Because the First Nations people did most of the work of beaver hunting, the company needed few French employees. The sparsely-populated New France almost fell to hostile Iroquois forces completely as well. In 1660, settler Adam Dollard des Ormeaux led a Canadian and Huron militia against a much larger Iroquois force; none of the Canadians survived, although they did turn back the Iroquois invasion.


title: New France

text: In 1627, Quebec had only eighty-five French colonists and was easily overwhelmed two years later when three English privateers plundered the settlement. In 1663, New France finally became more secure when Louis XIV made it a royal province, taking control away from the Company of One Hundred Associates. In the same year the Société Notre-Dame de Montréal ceded its possessions to the Seminaire de Saint-Sulpice.


title: New France

text: The Crown paid for transatlantic passages and offered other incentives to those willing to move to New France as well, after which the population of New France grew to three thousand.


title: New France

text: In 1665, Louis XIV sent a French garrison, the Carignan-Salières Regiment, to Quebec. The colonial government was reformed along the lines of the government of France, with the Governor General and Intendant subordinate to the French Minister of the Marine. In 1665, Jean Talon Minister of the Marine accepted an appointment from Jean-Baptiste Colbert as the first Intendant of New France. These reforms limited the power of the Bishop of Quebec, who had held the greatest amount of power after the death of Champlain.


title: New France

text: Talon tried reforming the seigneurial system by forcing the "seigneurs" to reside on their land and limiting the size of the "seigneuries," intending to make more land available to new settlers. Talon's attempts failed since very few settlers arrived and the various industries he established failed to surpass the importance of the fur trade.


title: New France

text: The first settler was brought to Quebec by Champlainthe apothecary Louis Hébert and his family, of Paris. They came expressly to settle, stay in one place to make the New France settlement function. Waves of recruits came in response to the requests for men with specific skills, like farming, apothecaries, blacksmiths. As couples married, cash incentives to have large families were put in place, and were effective.


title: New France

text: To strengthen and make the colony the centre of France's colonial empire, Louis XIV decided to send single women, between 15 and 30 years old and known as the King's Daughters, or, in French, "les filles du roi", to New France. He also paid for their passages and granted goods or money as their dowries if or when they married. Approximately 800 girls and women went there during 1663–1673. The King's Daughters found husbands among the male settlers new lives for themselves within two years of their respective immigrations. They came on their own choice, many because they could not contract favorable marriages in the French social hierarchy. Primarily, they came from Parisian, Norman, and west-central commoner families. By 1672, the population of New France had risen to 6,700 people, a marked increase from the population of 3,200 people in 1663.


title: New France

text: At the same time, the government encouraged marriages with the indigenous peoples and welcomed indentured servants, or "engagés" sent to New France. The women there contributed to establishing family life, civil society, and rapid demographic growth significantly. There was a high demand for children since they contributed to farmers' prosperity from an early age and they could receive abundant food supplies. Women there also bore about 30% more children than comparable women who remained in France. Landry says, "Canadians had an exceptional diet for their time. This was due to the natural abundance of meat, fish, and pure water; the good food conservation conditions during the winter; and an adequate wheat supply in most years."


title: New France

text: Besides household duties, some women participated in the fur trade, the major source of money in New France. They worked at home alongside their husbands or fathers as merchants, clerks, and provisioners. Some were widows who took over their husbands' roles. Some even became independent and active entrepreneurs.


title: New France

text: The French extended their territorial claim to the south and to the west of the American colonies late in the 17th century, naming it for King Louis XIV, as La Louisiane. In 1682, René-Robert Cavelier, Sieur de La Salle explored the Ohio River Valley and the Mississippi River Valley, and he claimed the entire territory for France as far south as the Gulf of Mexico.


title: New France

text: La Salle attempted to establish the first southern colony in the new territory in 1685, but inaccurate maps and navigational issues led him to instead establish his Fort Saint Louis in what is now Texas. The colony was devastated by disease, and the surviving settlers were killed in 1688, in an attack by the area's indigenous population. Other parts of Louisiana were settled and developed with success, such as New Orleans and southern Illinois, leaving a strong French influence in these areas long after the Louisiana Purchase.


title: New France

text: Many strategic forts were built there, under the orders of Governor Louis de Buade de Frontenac. Forts were also built in the older portions of New France that had not yet been settled. Many of these forts were garrisoned by the Troupes de la Marine, the only regular soldiers in New France between 1683 and 1755.


title: New France

text: The European population grew slowly under French rule, thus remained relatively low as growth was largely achieved through natural births, rather than by immigration. Most of the French were farmers, and the rate of natural increase among the settlers themselves was very high. The women had about 30 per cent more children than comparable women who remained in France. Yves Landry says, "Canadians had an exceptional diet for their time." The 1666 census of New France was the first census conducted in North America. It was organized by Jean Talon, the first Intendant of New France, between 1665 and 1666. According to Talon's census there were 3,215 people in New France, comprising 538 separate families. The census showed a great difference in the number of men at 2,034 versus 1,181 women.


title: New France

text: By the early 1700s the New France settlers were well established along the Saint Lawrence River and Acadian Peninsula with a population around 15,000 to 16,000. The first population figures for Acadia are from 1671, which enumerated only 450 people.


title: New France

text: After the Treaty of Utrecht in 1713, New France began to prosper. Industries such as fishing and farming, which had failed under Talon, began to flourish. A "King's Highway" ("Chemin du Roy") was built between Montreal and Quebec to encourage faster trade. The shipping industry also flourished as new ports were built and old ones were upgraded. The number of colonists greatly increased. By 1720, Canada had become a self-sufficient colony with a population of 24,594.


title: New France

text: Mainly due to natural increase and modest immigration from Northwest France (Brittany, Normandy, Île-de-France, Poitou-Charentes and Pays de la Loire) the population of Canada increased to 55,000 according to the last French census of 1754. This was an increase from 42,701 in 1730. By 1765, the population approached 70,000.


title: New France

text: By 1714, the Acadian population had expanded to over 2,500 and to about 13,000 people by the end of the 1750s. This was mostly from natural increase rather than immigration that affected other French settlements.


title: New France

text: European population of Louisiana is estimated at around 5,000 by the 1720s. This would dramatically change in the mid-1730s with the loss of 2,000 French settlers and the introduction of African slaves. Enslaved men, women and children represented approximately 65 percent of the 6,000 non-indigenous population of Louisiana by the end of French rule.


title: New France

text: According to the staples thesis, the economic development of New France was marked by the emergence of successive economies based on staple commodities, each of which dictated the political and cultural settings of the time. During the 16th and early 17th centuries New France's economy was heavily centered on its Atlantic fisheries. This would change in the later half of the 17th and 18th centuries as French settlement penetrated further into the continental interior. Here French economic interests would shift and concentrate itself on the development of the North American fur trade. It would soon become the new staple good that would strengthen and drive New France's economy, in particular that of Montreal, for the next century.