CO/VL
Angry by Choice
Catalogue of Organisms
Chinleana
Doc Madhattan
Games with Words
Genomics, Medicine, and Pseudoscience
History of Geology
Moss Plants and More
Plektix
RRResearch
Skeptic Wonder
The Culture of Chemistry
The Phytophactor
The View from a Microbiologist
Variety of Life
Field of Science
Colubridae
10 minutes ago in Variety of Life
Lichen Darklings
3 hours ago in Catalogue of Organisms
Is a 7-minute workout just as good as an hour-long bike ride? Yes, it can be.
4 days ago in Genomics, Medicine, and Pseudoscience
Friday 'fabulous Flower - Mock orange
6 days ago in The Phytophactor
Rutherford on tools and theories (and machine learning)
1 week ago in The Curious Wavefunction
Mathematics and HIV
1 month ago in Doc Madhattan
Rapidly Eyeball Abstract and Diagrams
5 months ago in Pleiotropy
Does mathematics carry human biases?
1 year ago in PLEKTIX
The Alvarez and the Crater of Doom
1 year ago in History of Geology
Thinking about a post-pandemic world
1 year ago in RRResearch
1 year ago in Angry by Choice
Easter fires: Rainbow demonstration rises again
2 years ago in The Culture of Chemistry
A New Placodont from the Late Triassic of China
3 years ago in Chinleana
Posted: July 22, 2018 at 03:03PM
3 years ago in Field Notes
Bryophyte Herbarium Survey
4 years ago in Moss Plants and More
Harnessing innate immunity to cure HIV
5 years ago in Rule of 6ix
5 years ago in Games with Words
If You Are Against Nuclear Power
6 years ago in The Astronomist
A New Wave of Science Blogging?
6 years ago in Labs
Update: Tree of Eukaryotes (parasitology edition)
6 years ago in Skeptic Wonder
post doc job opportunity on ribosome biochemistry!
6 years ago in Protein Evolution and Other Musings
Growing the kidney: re-blogged from Science Bitez
6 years ago in The View from a Microbiologist
Blogging Microbes- Communicating Microbiology to Netizens
7 years ago in Memoirs of a Defective Brain
8 years ago in inkfish
The Molecular Circus
9 years ago in A is for Aspirin
The Lure of the Obscure? Guest Post by Frank Stahl
9 years ago in Sex, Genes & Evolution
Girlybits 101, now with fewer scary parts!
10 years ago in C6-H12-O6
Lab Rat Moving House
10 years ago in Life of a Lab Rat
Goodbye FoS, thanks for all the laughs
10 years ago in Disease Prone
JAPAN'S RADIOACTIVE OCEAN | DEEP BLUE HOME
10 years ago in The Greenhouse
Slideshow of NASA's Stardust-NExT Mission Comet Tempel 1 Flyby
10 years ago in The Large Picture Blog
in The Biology Files
Accretionary Wedge #28: Have you ever danced with the devil in the pale moonlight?
By David Bressan on Saturday, October 30, 2010
"Tell me something, my friend. You ever dance with the devil in the pale moonlight?"
(Batman 1989)
Strange signs can be found in some rocks of the Dolomites, they resemble somehow the imprint of a hoof, but a very large hoof!
Ancient myths know for certain, that these must be the imprints of the hoofs of the devil and his demons. Dark legends tell also about places where the devil meets witches and sorcerers, who sell their soul to him and gain magic powers and the ability to shift their shape.
Fig.1. Marcantonio Raimondi (1475-1534) "Lo stregozzo" ("The witches gathering", 1520-1527).
Some of these sorcerers like even to adopt the form of a putrefied mule skeleton during these gatherings.
Fig.2. David Ryckaert the Younger (1612-1661) "La ronde de Les Farfadets" ("The Dance of the Elves").
Dancing the entire night long they leave back only the imprints of their hoofs in the rocks, but at the first cockcrow, even the mightiest evil force has to retire back into hell.
Modern explanation for the strange hoof-like cross sections is maybe less scarier, but not less intriguing:
The region of the Dolomites during the Norian-Rhaetian (216-199Ma) was situated in an extensive tropical shallow water zone. Gradually this area deepened again, but always remained still under a few meters to tens of meters of water column, while in the west and east deep basins developed due to tectonic processes. At the top of this giant submarine ridge limestones were deposited.
The Dachstein limestone is composed of well bedded limestones and reaches some hundreds of meters thickness. Like in the Hauptdolomite one can find several breccia layers composed of material swept together by storm events. Some of them show outstanding black mud pebbles, which are indicative for larger areas having been islands for a longer time.
The deeper parts were colonized by bivalves and single coral colonies. These bivalves (Megalodus in the Hauptdolomite and Conchodon in the Dachstein limestone) can often be observed in cross sections and inspired various myths in the Dolomites to explain them.
Fig.5. Bedded Dachsteinkalk- Formation, the cross sections are quit hard to recover, however...
Fig.6. ...here a hand-specimen that made it until home - of Megalodus gümbeli from the Hauptdolomit-Formation. During the recrystallization of the limestone the calcite components of the shell got lost, here we see an interior cast of the bivalve (makes it also easy to release it from its rock - grave)
VOLKMAR, S. & VOLKMAR, M. (2005): Introduction to the geology of South Tyrol. Ufficio geologia e prove materiali - Provincia Autonoma di Bolzano-Alto Adige: 80
Labels: Accretionary Wedge, Ancient times, Fossil Legends
The historical problems for women geologists: Travel and Gear
By David Bressan on Wednesday, October 27, 2010
The geologist who wishes to study rocks is faced by a major problem: Rocks must be studied in the field and the best outcrops have the nasty tendency to be located in difficult terrain, in desolate landscapes, in narrow gorges and steep mountains - and because the mountain normally doesn't come to the geologist, the geologist has to travel to the mountain.
Geology usually requires outdoor activities in remote, inhospitable and often hazardous environments. Originally this was perceived as a occupation for a working-class man who, dressed in appropriate clothes, ragged and dirty, was forced to be in the field. It was hard to imagine that a gentleman would engage in such an activity and it's seemed even less comprehensible that a woman could and should be allowed to the same thing!
As results of these social prejudices throughout history women geologists have encountered difficulties travelling and working in the field, whether their sites of interest were close by or abroad. Excuses to prevent women engaging in geology could be the simple lack of unsuitable clothes, the lack of proper funding and the inappropriate appearance of a woman travelling alone, to more direct reasons like sexual harassment and open discrimination.
Solitary girls and women working in the field however were tolerated in the social lower classes, like professional fossil collector and dealer Mary Anning (1799-1848) of Lyme Regis (Dorset), but for upper-class women engaging in field research was much more difficult. Woman could minimize these "problems" by collecting fossils and studying rocks in their local environment, for example on private property or in the surroundings of their home, where their social status was known and their behaviour somehow tolerated. However upper-class women had to face inevitably troubles as soon as they left familiar paths.
In a letter by English stratigrapher and palaeontologist Etheldred Benett (1775-1845) to Gideon Mantell dated to November 1835, she remarks:
"A lady going into the quarries is a signal for the men begging money for beer, and the few times I have been there [i.e., in Portland] I never got a specimen worth bringing home. All my Portland fossils have been purchased in Weymouth!"
A second accepted possibility for a woman to engage in earth sciences was following her husband, father or brother in the field and acting as a "geological assistant":
"After the last Geological Society meeting of the spring season, the leading researchers gathered up their hammers and their wives and set off on extensive stratigraphical tours."
(SECORD 1990)
The problem of the clothing persisted almost until the 19th century, even a gentleman geologist was expected to wear cylinder and tailcoat in the field, and women dressed according to the most recent mode with "cages" and "horrid iron girdles round their legs" (Roderick Murchinson in 1850 on his wife, who accompanied him into the field).
However with the introducing of cycling and other sport clubs and increasing acceptance by the society of geologist appearance and behaviour soon more practical wardrobe became prevalent. The depiction by Henry De la Beche of pioneer fossil collector Mary Anning working along the foreshore east of Lyme gives us a good impression how a woman geologists dressed at these times:
"Hammer in hand; Mary is depicted wearing sturdy boots or clogs, heavy clothing and a top hat, the protective clothing of a working-class woman. Top hats, made of felted wool repeatedly coated with shellac until quite stiff, might appear oddly formal today, but they were the crash helmets of the time and were worn by many geologists when they were doing fieldwork in order to provide protection from falling rocks."
(GOODHUE 2005) Fig. 1. Cartoon of Mary Anning working in protective gear, painted by Henry Thomas De la Beche. (GOODHUE 2005).
With the development of public transportation systems in the 18-19th century, like the train, travelling became less complicated and accepted by society also for women - by travelling in a "closed box", women became highly mobile but could maintain their "required" privacy.
The first field trip of the Geologists' Association's of the United Kingdom, with many women geologists participating, was also made by train, the trip April 9, 1860 lead to Folkestone, the second to Maidstone (June 19, 1860) to inspect the Hythe beds, which had yielded the type specimen of Iguanodon mantelli just 26 years earlier. Fig.2. Geological excursion by train in 1914 by the Geologists' Association to Hertford (BUREK & KÖLBL-EBERT 2007).
Later, cycling excursions were introduced by the society but these proved much less popular. At the beginning of the 20th century a even more practically vehicle was introduced: the autobus, followed soon by the private car.
BUREK, C.V. & KÖLBL-EBERT, M. (2007): The historical problems of travel for women undertaking geological fieldwork. In BUREK, C. V. & HIGGS, B. (eds): The Role of Women in the History of Geology. Geological Society, London, Special Publications, 281: 115-122
GOODHUE, T.W. (2005): Mary Anning: the fossilist as exegete. Endeavour Vol.29 (1): 28-32SECORD, J. 1990: Controversy in Victorian Geology: The Cambrian-Silurian Dispute. Princeton University Press, Princeton
Labels: 19th century, 20th century, Cartoons and Earth Sciences, Earth Science VS Pop Culture, England, Expeditions, Geology, Geology and Society, Heretic geologists, Life as geologist
SnowCow
By David Bressan on Tuesday, October 26, 2010
Fig.1. A Cow stands in the Snow...
"In the beginning there was Ginnungagap – the void with no bottom. In the south it was confined by Muspelheim, the land of eternal burning fire, in the north laid Nebelheim, an eternally frozen, desolate land.
Located in the center of Nebelheim there was a poisoned spring, feeding eleven poisoned rivers. In the eternal darkness and coldness of Nebelheim, the water immediately froze to ice, so that the ice could reach far up to the border of Ginnungagap. Even the poisoned vapour, emanating from the dead rivers, froze to icicles. No live could exist here.
In the heat from Muspelheim, no live could exist ether, it would burn immediately. But between these two hells, one day warm winds transported some sparks on the frozen water, and melted some ice.
From the ice emerged Audhumla (the "milk rich"), the cosmic cow. Finding nothing to grazing, because still grass wasn't´ created, she began licking the salty ice. Licking the ice there emerged Ymir, the first giant – even if some tell that Ymir was there before Audhumla, but in this case he had to suffer famine, because only with the appearance of Audhumla he could finally drink some fresh milk.
But in every case, licking and licking for three days, from the ice emerged Buri – the first god. His son Bör wedded Bestla, the daughter of a giant, and from this relationship three sons were born: Odin, Vili and Ve. They finally killed the giant Ymir, and from his corpse they created the world, mountains, the sea, humankind, and grass, so that Audhumla and her descendants could finally graze."
The Creation of the World according to the Sagas of the Icelanders.
Labels: Ancient times
Cabinets of curiosities #1: The jolly old beast
By David Bressan on Sunday, October 24, 2010
During the European Renaissance (14th to the 17th century) kings, aristocrats, rich merchants and scholars collected curiosities like fossils, minerals, religious or historical artefacts, antiquities, stuffed animals or at least parts of them, and lot of other stuff and displayed them in "Cabinets of curiosities/wonders" (from the German term Wunderkammer).
So here I present some curiosities as I found and collected them in my Cabinets of curiosities:
Fig.1. Dragon by U. Aldrovandi, from his opus magnus "Historia serpentum et draconum" (1640).
In the sea of internet a lot of dragons can be found: Dragons by Ulisse Aldrovandi (1522-1605) - I mentioned in an earlier post this Renaissance naturalist and his observations on fossils, however he was also an dedicated biologists, especially ornithologist and ichthyologist, the depictions of the animals are marvellous.
It is often forgotten that becoming a fossil is quite hard, it's an own science called Taphonomy - and the actual Carnal Carnival dealing with this topic is found on Brian Switeks "Laelaps" post - presenting us to our ultimate fate: "Death and Decay".
But it's also hard to find fossils; Michael D. Barton on his blog "The Dispersal of Darwin" linked to various articles on the first fossil hunters, like the Italian geologist Giambattista Brocchi (1771-1826), the brave and talented Mary Anning (1799 - 1847), who discovered the first recognized sea dragons, the baron of science Cuvier (1769-1832) and the explorer Humbodt (1769-1859), and Darwin as geologist.
David Orr on "Love in the Time of Chasmosaurs" invite us to visit the dragons of the land as they were displayed in the Crystal Palace in 1854. To celebrate the inauguration of the dinosaur models, Owen organized in December 1853 even a dinner inside one of the models.
Fig.3. The invitation to the dinner held inside Hawkins's iguanodon reconstruction in December 1853, figure from "A Buried History of Paleontology".
From reports published in the local newspaper and personal anecdotes of some of the participants it's seems that it was a frolicsomely party. The sculptor of the models, Hawkins himself, noted:
"The roaring chorus was so loud and enthusiastic that you could almost believe there roared a herd of Iguanodons."
"The jolly old beast
Is not deceased
There ´s life in him again! [ROAR!]"
Other monsters related to Owens are the terracotta figures of the Natural History Museum of London (Owen was the initiator of the museum), imagined by the artists Waterhouse between 1875-1876, and most of them were realized like the artist want.
Fig.4. Copulating dinosaurs, foto taken by Dinorider d'Andoandor.
Dinorider d'Andoandor posted this reconstruction of dinosaurs doing their best to prevent extinction - the question how dinosaurs copulated, especially species with spines on their back, is intriguing. And speaking of dinosaurs, 100 years ago, famous dinosaur hunter Barnum Brown found an amazing fossil site while drifting down the Red Deer River in Alberta.
And if H.G. Giger would be interested in palaeontology, I'm sure his Parasaurolophus would look a little like this (also note the creationist nightmare – the Precambrian Bunny).
And last but no least the marvellous story about the missing head of the headless chicken.
Searching for old TV-documentaries I rediscovered "Monsters We Met", about the colonization of earth by humans and the consequences for the fauna, the last episode deals with "The End of Eden", New Zealand 800 years ago.
Despite animals found a way in our imagination and religion, in the end we were the monster, we even forced to extinction one of the most strange fauna that ever was - the Megafauna of Australia.
Back to more recent times: History of Psychology remembers the contribution of Lamarck to Zoology and History of Evolution.
"What a pity that I only saw all these wonderful things in a dream, and that I can't actually see them everyday."
"Paris before Man" (1861)
Labels: Cabinets of curiosities
Prehistoric Monster Movie: The Mighty Gorga (1969)
The original movie King Kong is one of the most successful film released 77 years ago on March 2, 1933. It had a profound impact on the film industry, it is almost impossible to name all the movies inspired by King Kong, including many who have simply made copy and paste of the plot or the monster - a giant primate - with results that range from respectable to delusional and pathetic.
"The Mighty Gorga", produced in 1969 by David L. Hewitt, must be included in the last category.
The story of the film is a simple rip-off of the original:
In search of an attraction for his circus, a young explorer decides to lead an expedition into the unexplored regions of the Congo, to follow rumours about a giant creature hidden in the forest. Here they discover an isolated plateau, where dinosaurs and other prehistoric creatures, including Gorga, survived and are adored by the natives like gods.
The producers do not even try denying that they copied from the original, but what makes this film mentionable is his high "trash" factor - the special effects must be seen to be believed - simple sock puppets moved before a projection of the real footage movie. Hewitt even "borrowed "some scenes from other films, like "Goliath and the Dragon" (1960).
Labels: Earth Science VS Pop Culture, Prehistoric Monster Movie
Taphonomy of Cave Environments
"If you gaze long into an abyss, the abyss will gaze back into you."
Friedrich Nitzsche
Caves always fascinated men, and tales of monstrous bones found in them maybe inspired legends referring to caves as forbidden passages - according to the Maya the karstic caves of the Yucatan peninsula were the gates to Xibalba, the "Place of fear", reign of the Death Gods.
A comprehensibly fear, whoever visit and enters a natural cave will still today be surprised, maybe even concerned, by the darkness and quietness that encompass him. In a reign without daylight or seasons the concept of time becomes meaningless, and it would seem no surprise to discover the bones of a long dead monsters hidden in the shadows of our faint light.
Fig.1. An imaginative drawing of William Buckland transported back to Pleistocene times at Kirkdale Cavern, Yorkshire - a hyaena den full of bones of Pleistocene mammals. (After Buckland, 1823.)
Bone accumulations in caves were known since antiquity - Greek sailors tell that they found the bones of Cyclops in caves on the island of Sicily. Some centuries later, the German Jesuit Athanasius Kircher visited and studied these bones, and in 1678 published an extensive report on this matter, appropriately named "Mundus subterraneus", proclaiming that the remains represent at least the bones of four different kind (and sizes) of prehistoric giants. Some centuries later the fossils were recognised to belonging to Pleistocene elephants. In the 18th and 19th century the bones, even when recognized belonging to animals, were mostly explained as the remains of the victims drown in the biblical flood, and later transported and deposited by the water into the caves.
The first insights that the bones were of animals living in or nearby the cave came in 1794, when the German physician Johann Christian Rosenmüller described the cave bear as species Ursus spelaeus. He rejected the idea of a flood transporting the bones into the cave, and argued
"the amount of bones can not be explained in a simpler way, then assuming that the animals, from which they came, lived, reproduced and died in the caves."
Despite these considerations, until 1970 accumulations of animal remains and broken bones were mostly attributed to human activity, even if earlier observations showed how carnivores can gather and process bones in similar way as expected by human behaviour. Reverend William Buckland, who intensively studied caves and the sediments during the first half of the 19th century, published his results in his masterpiece "Reliquiae diluvianae" (1824):
"I have had an opportunity of seeing a Cape hyaena at Oxford...I was enabled also to observe the animal´s mode of proceeding in the destruction of bones: the shin bone of an ox being presented to this hyaena, he began to bite off with his molar teeth large fragments from its upper extremity, and swallowed them whole as fast as they were broken off. On his reaching the medullary cavity, the bone split into angular fragments...he went on cracking it till he had extracted all the marrow... this done, he left untouched the lower condyle, which contains no marrow, and is very hard. The state and form of this residuary fragment are precisely like those of similar bones at Kirkdale; the marks of teeth on it are very few...these few, however, entirely resemble the impressions we find on the bones of Kirkdale; the small splinters also in form and size, and manner of fracture, are not distinguishable from the fossil ones...there is absolutely no difference between them, except in point of age."
(BUCKLAND 1824 pag. 34)
Fig.2. Section trough Dream Cave near Wirksworth in central England, drawing by Webster based on a sketch by Buckland, published in 1823. A skeleton of a rhinoceros (G) had been found buried in the debris below a fissure (D). Buckland argued that the carcass must have fallen into the cave while being swept along during a geologically recent deluge.
However caves are an environment that in principle is hostile to life. Few mammals, including the hyena and the cave men, regularly use or used deeper areas of the cave, prominent exceptions being bats or the extinct cave bear. Thus the presences of animal remains in caves are the result of complicated and various taphonomic processes.
Taphonomic assemblages in caves often represent a collection of various animals of different geographically locations and time periods. Carcasses of animals from different environments can be washed together, and caves act as sample bag for many centuries, providing a false species assemblage. Accurate interpretation of fossil assemblages can so be challenging.
Fig.3. The "Passalacqua" quarry, situated at the north-western margin of the Gargano promontory, close to the village of Apricena in the italian province Apulia. Here in sediments deposited in a karst network, discovered during quarrying of the limestone, a very diverse and now well-documented fossil vertebrate assemblage was discovered. The sediments returned also lithic artefacts, estimated in an age interval of 1,3 and 1,7 Ma, documenting an early hominid occurrence in the Early Pleistocene, and thus now constitute the oldest record in Europe. The karst network developed during two phases. The first, Miocene in age, extents in the Mesozoic limestone of the "Sannicandro Formation", and consists of red clays ("terra rossa") in part reworked and redeposit by flood events with a huge diversity of vertebrates remains. The second phase of occurred after a tectonic uplift of the Gargano peninsula during the Pliocene. Fissures can so contain in the lower part fossils attributed to the Miocene fauna, and in the upper parts fossils of the Villafranchian mammal age (Upper Pliocene and Lower Pleistocene).
To fully understand the taphonomy of caves it is necessary to consider the depositional environment and sediments found in caves: Sediments can be of very different origins, clastic sediments derived from collapse of cavern roofs, sediments transported into the cave by superficial and underground streams or accumulating under sinkholes, chemical deposition of minerals, like speleotherms, and sediments resulting from the accumulation of organic matter, like guano.
Fig.4. Examples of Speleothems or flowstones - deposition of minerals like calcite from aqueous solutions - found in the Conturines Cave in the Dolomites (Alps), the highest situated locality were fossils of the Cave bear (Ursus spelaeus) were found. The floor of the cave is covered by a 2m thick flowstone that shows a fine lamination, maybe representing annual growth layers. Such deposits are well suited for radiometric dating method because their calcite crystals are usually large and have little tendency to recrystallize and incorporate radioactive elements only in the period of crystal growth. However in this case the fossils were found in the sand overlying the flowstones (older than 350kyr), implying that the fossils are younger as this unit.
In contrast to the surface, caves are however very stable environments - the transport of sediments in conduit systems is episodic with abrupt storm flow and little or no movement during low flow conditions. Carcasses and bones can so be transported into the cave by sudden flood events or mudflows, and become accumulated during phases of decreasing flow.
Fig.5. Example of clastic sediments as infill's of the Mammut-Höhle in the Dachstein-massif (Austria). Rounded pebbles, consisting mainly of siliciclastic and metamorphic rocks, form a massive conglomerate (Augenstein-Formation) that became cemented and later partially eroded. The source and age of this unit is unclear, probably transported from the Central-Alpine to the north during the Late Eocene to Early Oligocene.
For example the two skeletons of Australopithecus sediba, described in April 2010, were discovered in a massive, up to 1.5-m-thick stratigraphic unit filling a cave in the karst landscape of South Africa, The heterogeneity in the sediment-grains, ranging from sand to pebbles to larger boulders, and lacking sedimentary structures (like stratification) suggested the deposition of this unit as a single event, like a debris flow, maybe caused by a flood or a storm. The superb preservation and state of articulation of fossil material also indicate rapid deposition, limited transport distance, and laminar flow conditions consistent with a debris flows.
A peculiar bone bed formation found in caves is under sinkholes. Fissures, hidden under vegetation, snow cover or a thin soil layer can act like a pitfall trap - animals fell trough them and die on the impact or later by starvation. Under these natural traps a talus of rubble accumulates that contains a chaotic assemblage of bones from animals died at different times.
In parts of the cave accessible by animals, and used as shelter or resting place, animals that die of natural causes, get lost or become entrapped can became accumulated. Many carnivorous animals, mammals and birds, carry their prey or parts of it in their shelter, were the bones later are found (a prominent recent example is the den of the man-eaters of Tsavo).
Buckland notes about hyenas that:
"Their habit of digging human bodies from the grave, and dragging them to their den, and accumulating around it the bones of all kinds of animals,...[] "
(BUCKLAND 1824 pag.22)
Fig.6. Fissures that act as sediment and also bone accumulation traps can develop not only in carbonates, but also in evaporitic sediments. Near the small village of Westeregeln (Thuringia, Germany) past quarrying activity for clay has exposed underlying Mesozoic gypsum and limestone formations, which in the upper part show an intensive "karst" network, refilled with Pleistocene sediments and fossils. The uppermost part of the stratigraphic column of the infilling sediments is represented by a postglacial soil, developed on Loess - aeolian sediment deposited during the last great glacial period. These sediments cover ancient matrix supported breccias, presumably generated by partial collapse of former caves or fissures.
Fig.7. Between these breccias, mostly on the top of the deposits, lithic artefacts (marked by the plastic bags), bones of ice age mammals and hyena coprolites are found exclusively in pebbly horizons.
The amount of bone present and the species representation in prey assemblages vary from predator to predator but are always biased with respect to the community from which they came. Predator size, for example, is related to prey size, but it varies with seasonal and annual cycles of climate, habitat, and prey populations.
Even without this disadvantage, predators and other animals tend to have the nasty habit to break and destroy bones, by nibbling, gnawing, digesting or trampling on it, or by removing or mixing the sediment that should protect the bone.
Caves tend to have a very restricted catchment area of their "victims", delimited for example by the range of the predators living in them, or the area where entrances to the cave form pitfall-traps - that makes them suitable to reconstruct the conditions and species assemblage of a spatial delimitated ecosystems.
Caves and fissures can also gather animals' remains over a certain time interval, until they became filled or obstructed, under optimal conditions this enable a temporal reconstruction of the changes experienced by the ecosystem. Unfortunately homogenous sediments, produced by roof collapse or debris flows, tend to mix bones and remains of different time periods together, enabling a general but not time specific reconstruction of an ecosystem. Despite this inconvenient, caves are still important for palaeontology by their effect to gather, accumulate and perfectly preserve bones.
Fig.8. Generalized section of a cave as a sedimentary system. The numbers indicate different forms of accumulation of bones and sediment:
1. Breccias formation under a pitfall trap
2. and 3.Waterlain silts;
4. Den accumulation of bones;
5. Accumulation of bat remains beneath roosting area in the cave roof and accumulation of small mammals beneath owl roosting/nesting area in the cave roof;
6. Water transported mud from further inside the cave;
7. Speleothems;
8. Roof fall; Accumulation of bones of cave bear, died during hibernation in the deeper regions of the cave;
9. Former lower chamber of the cave that acted as a natural trap/ accumulation room of amalgamated debris flows.
The sedimentation rate in caves is irregular and very low, however bones, even when exposed, can survive in caves for much longer time destruction or degradation as compared to the surface, until they become finally embedded.
"In all these cases, the bones found in caverns are never mineralised, but simply in the state of grave bones more or less decayed or incrusted by stalagmite"
The preservation of bones is helped by the stable conditions found in caves - bones are sheltered from atmospheric processes, and there are no or only minor changes of temperature, humidity or chemical parameters in the environment of the cave. The high content of dissolved minerals in the percolating water also helps to conserve skeletal remains by limiting chemical alteration. The oversaturated water is unable to dissolve more carbonate, and is so harmless to the bone-structure.
An inaccessible cave also protects bones and a carcass from large scavengers, decomposition occurs mainly by bacteria and smaller invertebrates - organism unable to disarticulate bones. Under optimal conditions, like no subsequent water transport, the result is a fully articulated skeleton, however such findings are still exceptional events.
In caves with speleotherms formation bones can become entrapped, fixed and in a certain manner "mummified" in their position by the new formed rock.
"The effect of the loam and stalagmite in preserving the bones from decomposition, by protecting them from all access of atmospheric air, has been very remarkable; some that had lain uncovered in the cave for a long time before the introduction of the loam were in various stages of decomposition; but even in these the further progress of decay appears to have been arrested as soon as they became covered with it; and in the greater number, little or no destruction of their form, and scarcely any of their substance, has taken place"
(BUCKLAND 1824, pag.12-13)
Fig.9. Bones of Cave bear (Ursus spelaeus) found in the Conturines Cave. The bones in this cave were scattered around on the floor or embedded in loose dolostone sand with pebbles. Some of the fossils became incorporated or covered by concretions and flowstones. Because of the inaccessibility of the cave and an observed bias in the age structure of the remains, they came from either young or very old individuals, it is thought that this cave served for hibernation, and eventually weak animals died during their winter sleep and their bones becoming incorporated in the cave sediments.
In even rarer circumstances the air circulation inside a cave can completely dry out a body, preventing even the decomposition work of bacteria - the result is a true mummified body.
Bone beds in caves were found and described all over the world, from the first scientific research in Victorian England to the studies of the chronology of extinction deduced from the remains of the Australian Megafauna conserved in caves, from the presumed bones of Cyclopes found in caves of the Mediterranean Sea to bones in mountain caves attributed to mythical dragons.
Beyond their mystical significance, caves have proven in the past, and also in the present, to be a stroke of luck for geologists and palaeontologists in the attempt to reconstruct past ecosystems and their inhabitants.
BUCKLAND, W. (1823): Reliquiae Diluvianae; or Observations on the Organic Remains Contained in caves, Fissures, and Diluvial Gravel, and on Other geological Phenomena, Attesting the Action of an Universal Deluge. John Murray. London: 303
GUNN. J. (ed.)(2006): Encyclopedia of Caves and Karst Science. Taylor and Francis Group, New-York, London: 1940
KOE, A.M. (2003): Pre-burial taphonomic characterisation of a vertebrate assemblage from a pitfall cave fossil deposit in southeastern Asutralia. Journal of Archaeological Science 30: 769-779
ROSENMÜLLER, J.C. (1795): Beiträge zur Geschichte und nähern Kenntniß fossiler Knochen. Georg Emil Beer, Leipzig.
RUDWICK, M.J.S. (2008): Worlds before Adam - The Reconstruction of Geohistory in the Age of Reform. The University of Chicago Press: 614
SASOWSKY, I.D. & MYLROIE, J. (ed.) (2007): Studies of Cave Sediments. Physical and Chemical Records of Paleoclimate. Springer: 329
PAVIA & ZUNINO (2009): Giornate di paleontologia IX edizione Apricena (FG), 28-31 Maggio 2009 - Guida alle escursioni 30 e 31 maggio 2009.
OSTBYE, E.; LAURIRTZEN, S.E.; MOE, D. & OSTBYE, K. (2006): Vertebrate remains in Holocene limestone cave sediments: faunal succession in the Sirijorda Cave, northern Norway. Boreas, 35: 142-158
Labels: 19th century, Alps, Ancient times, Austria, Fossil Legends, Geology, Geology and Society, Geomorphology, Heretic geologists, Italy, Life as geologist, Paleontology, Stratigraphy
History of Paleomammology: The Taphonomy of Hoplitomeryx
"The species of ruminants are the most difficult to distinguish from one another. Although they are sharply distinct from other quadrupeds, they resemble each other so much that to characterize genera one has to use parts such as the horns;…[]"
G. Cuvier "On the Fossil Bones of Ruminants Found in the Superficial Deposits."
The Italian fossil record of terrestrial mammals is relatively poor during the Early and Middle Miocene; it is only in the Late Miocene that the record of terrestrial vertebrates increases. The pre-Messinian sediments document the existence of three distinct bioprovinces, two of them characterised by various endemic species, denominated after the recent geographical regions the Abruzzi-Apulia and the Tusco-Sardinian paleobioprovince. The third, the Calabro-Sicily bioprovince, shows mainly non-endemic mammals with species distributed at these times also in North Africa.
Fig.2. Paleogeografic reconstruction of the Italian peninsula during the Miocene-Pliocene transition with the discussed localities. In green land areas, in brown the first highlands of the Apennines.
During the Miocene and the Early Pliocene sea level variations transformed repeatedly the area of the Italian peninsula in an archipelago with isolated islands of various sizes and a humid and warm climate - an ideal laboratory for evolution.
One of these today lost islands was the modern peninsula of Gargano, on the east coast of South Italy, separated at these times from the main land by a branch of the Adriatic Sea. Practically all fossil mammals of Gargano show extraordinary morphological signs of insularity. This faunal assemblage of the Abruzzi-Apulia bioprovince is known as Mikrotia-fauna, after the common genus of the endemic murid of the region.
A peculiar animal of this fauna is the genus Hoplitomeryx (LEINDERS 1984). This artiodactyl resembles in its reconstructed appearance the Muntjac, a basal representative of the deer family, but displays a unique combination of anatomically characters. Despite some specialisation in the structure of the limbs, the most astonishing features can be found on the skull of the animal - five horns (not antler like in the true deer), a pair of horns above each orbit and one central nasal horn, paired with prominent sabre like upper canines ("moschid" type).
These unusual combination of characteristics make the phylogenetic position of this animal inside the artiodacyls very uncertain, the only described species Hoplitomeryx matthei (LEINDERS 1984) is actually classified in a own family, Hoplitomerycidae, even if the fossil material of Gargano shows almost four to five distinct "size-classes" (from estimated 5 to 50kg body mass), that may represent single species (VAN DER GEER 2007).
If these classes represent in fact species, the uniform anatomical characters between them suggest a rapid adaptation and radiation from a common ancestor, who after the formation of the island of Gargano adapted quickly to the diverse habitats found on the island. The problem of differentiating the fossil species is based on the problem of dating the sediments that contain the fossils. The sediments show no stratification and the bones show no change in size trough the preserved stratigraphic column.
Three explanations for this observation are possible:
- the red clays are to disturbed to display a temporal variations and succession of different species
- different species existed in the same time period and became embedded in the red clays
- the size classes all represent the variation of one species
Despite the insecurities about the number of species, TORRE et al. in 2005 postulated an affinity of Hoplitomeryx to the basal ungulates of the family Choeropotamidae and Dacrytheridae, known from the Eocene of France and closely related to the Suidae. According to VAN DER GEER also an affinity with the ancestors of the modern North American pronghorn (Antilocapridae) is plausible.
The first fossils of Hoplitomeryx were found near the city of Foggia, in homogenous to weakly stratified red clays which partially fill the karst fissures of the underlying limestone substrate. In the late sixties and subsequent years from similar karst fissures of the promontory of Gargano further fossil material could be recovered. The fossils are found in reworked, homogenous to weakly stratified red clays (denominated "terra rossa"), which partially fill the paleo-karstic fissures of the Mesozoic limestone substrate. This karst network is truncated by a disconformity of Late Pliocene to Early Pleistocene sediments of marine origin.
The exact age of the terra rossa is uncertain, the stratigraphic correlation and the mammal chronology suggests a temporal range from the late Miocene to early Pliocene, with preferences from various authors to the Pliocene (VAN DER GEER 2007).
Fig.3. The "Passalacqua" quarry, situated at the north-western margin of the Gargano promontory, close to the village of Apricena in the italian province Apulia. Here in sediments deposited in a karst network, discovered during quarrying of the limestone, a very diverse and now well-documented fossil vertebrate assemblage was discovered.
Fig.4. Molar of Hoplitomeryx.
Until 1990 Hoplitomeryx was believed to be an exclusive genus of the former island of Gargano, but during a field campaign of the Museum of Palaeontology and Geology of the University of Florence a rich assemblage of Miocene vertebrates (crocodiles, turtles, various deer and an otter like animal) was discovered on the eastern ridge of the Mount Civita near Scontrone in the province of Abruzzo.
Found embedded in yellow limestone breccias the bones of various mammalian species were recognized, one of them identified as Hoplitomeryx. This discovery suggests a paleogeographic connection, maybe trough an episodic land bridge or smaller islands of the island of Gargano to the European mainland.
During the Messinian (7Ma) all the endemic species of the Tusco-sardinian bioprovince disappeared and were replaced by a continental fauna with clear European affinities (BONFIGLIO 2005).
This geological period is marked by a pronounced sea level drop of the Mediterranean Sea, causing deposition of thousand of meters thick evaporites. The former isolated islands get reconnected with the European continent, and a dramatic faunal turnover occurred.
Only on still isolated islands some species characteristic for the Abruzzi-Apulia bioprovince survived this dramatic episode until the Pliocene, but with the establishment of the tectonic raised land bridge from the promontory of Gargano to the Italian peninsula, the last Hoplitomeryx went extinct.
AGUSTI, J. & ANTON, M. (2002): Mammoths, Sabertooths, and Hominids - 65 Million Years of Mammalian Evolution in Europe. Columbia University Press: 313 (Figure 1. is taken from this book)
BONFIGLIO, L. (2005): Paleontologia dei vertebrati in Italia - Evoluzione biologica, significato ambientale e paleogeografia. Museo di Storia Naturale - Verona: 238
VAN DER GEER, A. (2007): The effect of insularity on the Eastern Mediterranean early cervoid Hoplitomeryx. The study of the forelimb. Quaternary International 182 (1): 145-159
Labels: 20th century, Africa, Italy, Paleontology, Stratigraphy
Dragons and Geology
Johann Jakob Scheuchzer (1672-1733) was a Swiss scholar, during his studies of medicine, and especially after, he travelled and visited Central Europe and the Swiss, and became interested in natural sciences. His experiences of the voyages were published first in the year 1708 appropriately under the title "Itinera alpine" (Itinera per Helvetiae alpinas regiones facta annis 1702-1711), a highly successful book with various reprints about observations of culture and nature in the Swiss Alps.
In the introduction by the editor we can read:
"The name of Scheuchzer is famous in the entire world of culture. The author was in the best conditions to make valid discoveries during his explorations. He worked with incredible determination without drooping, no danger, no costs, no difficulty were to large for this great man."
Fig.1. The title page of "Itinera alpina" by Johann Jakob Scheuchzer, ca. 1702-1711.
Between the years 1702 and 1711 Scheuchzer travelled for eleven times trough his Swiss homeland, and collected his observations and opinions in the first scientific publications on the Alps, intended (in part) to refute popular superstition.
Scheuchzer, like many other naturalists of his time, did not see a contradiction in publishing own and exact observation and rumours in the same book. In the German translation of the "Itinera alpina" by Johann Georg Sulzer, published in 1746 under the title "Natur-Geschichte des Schweizerlandes ( natural history of the country of Swiss)" we read about dragons:
"In the summer of the year 1717 Joseph Gackerer from Neftls... a half hour from Glarus...[]… encountered an animal with the head of a cat, with eyes sticking out, it was long a foot, with a thick body, four limbs, and something like breasts pending from the belly, the tail was a foot long, the entire body was covered by scales and coloured. The man breached it with a stick; it was soft and full of poisoned blood, so that from some drops spilled his leg became swollen.
I requested to mister Tschudi, pastor at Schwanken, that he would find a honest person which would search for the bones of this person, so in April 1718 he send some to me, which I hold in collection as rare specimens."
Fig.2-5. Until the 18th century the inhabitants of remote valleys in the Alps were convinced that hidden in the forests and caves strange creatures lived, lizards with multiple tails and serpents with a human face.
In his "Itinera alpine" (1708) Scheuchzer dedicates a chapter to describe and depicts various reports of encounters with these creatures. One eyewitness reports to have observed a flying dragon (draconum alatum, fig.5) with a breath of fire in a not specified locality of the Swiss Alps, other stories tell about snakes with limbs or faces almost human (fig1. and 4.) or two tails and two tongues, with a body covered by scales (fig.3.)
Scheuchzer, like many other naturalists interested in dragons of his time, did not see a contradiction in publishing own and exact observation and rumours in the same book...
"From the evil dragon must also be told…[]…Years ago, an honest man named Mcyer …[recounts] … above the village of Ommen under the shade of a large fir tree was seen to lie [a dragon]. He had legs and wings, which were characterized by red spots, [the wings] glistening like silver.
When he take breath it sounded like he sighed, and from time to time he shook the wings.
The man turned back as soon as he had seen him. Two days afterwards there was a storm with hail, which confirms the common believe of locals that severe storms occur, after a dragon is spotted. This would not be without reason. Because we know that after the dilution of the air and before it rains creatures like snakes, lizards and similar animals tend to come out from their holes."
Scheuchzer however is sometimes sceptic about the local legends, and correctly notes in one case that bones attributed to dragons are more probably from modern and known animals:
"[]...an observation of the year 1718, there in a cave on a very high mountain, called Ober-Urner-Schwendi, there were found some bones, declared as the remains of a dragon, but after my judgement these are nothing more than the remains of a bear, which maybe had his winter accommodation in the cave, and because of the collapse of the entrance had must died by starvation."
In the end he remains optimistic that at least some stories have a real background, that they depict encounters with rare, but existing creatures yet not recognized by naturalists:
"At last I must mention that furious rivers from the mountains are called by the locals of the Alps also dragons. If a river flows down from the mountains, and carries large stone, trees and other things with it, so they say: The dragon became unchained...[]... that many wrong stories about the dragons have their source in this fact.
However I assume, that by comparison with the dragons from the Swiss and foreign [countries], that such animals exist, they could be a rare species of animals, or, as many say, deformed snakes, because not all are of same kind, some have wings, other are without limbs, who will be attributed to snakes, other have limbs, so that we should compare them to lizards. They differ also in colour, scales and form of the [body-] parts."
Apart from biology, mythology and dracology, Scheuchzer argued also about geology: the formation of the mountains, the form and the distribution of petrifactions, the significance of the strata in the rocks and of caves, why resources are distributed sporadic in the landscape and how and where springs occur.
From his voyages and connection to other naturalists Scheuchzer collected many petrifactions of plants, and exposed them in Zürich. In 1709 he finally published the summary of his studies on these fossils, in a work entitled "Herbarium Diluvianum", very successful and so reedited in 1723. On 14 plates he displays many fossils plants coming from the English Carboniferous, the Permian of Germany and the Swiss Cainozoic, including plant cast found in travertine.
Scheuchzer recognized the inorganic nature of dendrites, he attributed them to the Pseudophyta (Lapides, qui plantarum figuras mentiuntur), mineral deposits in rocks that only resembles plants and noted "productas esse has figuras et mortu fluidi alicuius inter duo solida inclusi, compressi et sese inter illa diffundentis" - that this forms are made by percolation of a fluid, entrapped and pressed into two strata where it spread.
This observation is even more admirable, considering that still in the year 1879 some dendrites found in marls of Siberia were described by the palaeobotanist ANGERS as "Eopteris", a hypothetical primordial fern .
Fig.2. Dendrites enclosed in quartz crystals. Scheuchzer hypothesised that crystals were build by much smaller "units" resembling always the crystal form, and it thus was possible to grow crystals.
In the second edition of 1723 Scheuchzer adopts a new, more "modern" classification system, and adds a chapter of fossils that can't be classified in the system "Plantae ad nullam certam classem redigendae".
In his first publications, Scheuchzer (as in "Lithographia Helvetica") following the common theory of these times, considered petrifactions more as spontaneous generated features in the rocks as remains of once living animals, drown by the biblical flood. However after translating in 1704 the book by J. WOODWARD "Essay toward a Natural History of the earth" (1692) he changed opinion ( the title "Herbarium Diluvianum" enforces this change of mind) and tried even to determinate the month when the flood occurred by studying the plant remains.
In his "Naturgeschichte des Schweizerlandes" (1716), the natural history of Swiss, Scheuchzer merged his exact natural observations with the biblical story about the formation of earth and the flood myth, in part based on works of other naturalists, but also contributing new and revolutionary ideas.
Scheuchzer tries to explain the phenomena described in the bible by a natural process, the birth of earth and the flood, even if created or send by god, were no unexplainable miracles, but caused and controlled by natural laws:
From a primordial "mud" -earth by rupturing were build up the first mountains. Concentration of precious minerals occurred by percolating gas and evaporation, from these deposits subterranean rivers still today spread, forming hydrothermal springs.
In accordance with this theory, caves and fissures are features caused by the selective erosion of weaker rocks by subterranean rivers and water.
Fig.3. Scheuchzer also got interested in hydrology and the formation of springs. He proposed that in the underground there exist "subterranean rivers", feed by lakes, flowing through the rock until emerging again to the surface as spring. This theory could also explain the chemical properties of the springs, especially hydrothermal springs. The water solves minerals from veins deep within the mountain, and carries it to the surface.
Fig.4. Visiting in the year 1705 the Rhône Glacier, Scheuchzer published his observations of the "true nature of the springs of the river Rhône".
This engraving shows the "false springs at the mountain Furca" (M, N, O - left and right of the picture) and the "true springs" (J, K, L) coming from the snout of the "great glacier" (A-F), surrounded by the "small glacier" (G, H).
Initially the mountains were covered by the sea, but later emerged. The stratification and diversity of rocks is however a proof that various inundation occurred at different times, the last the flood of the bible.It's interesting to note that Scheuchzer tried also the explained the tilting of strata, who couldn't possibly be deposited by a flood in the observed positions, by rupture and tectonic movements.
Despite many correct guesses regarding geology and palaeontology, even more admirable considering the knowledge of earth at these times, Scheuchzer is unjustly remembered only for one major error - in 1726 he published his most famous work, the description of the presumed remains of an eyewitness of the flood: the "Homo diluvii testis", a fossil that was later identified by Cuvier as skeleton of a giant salamander.
MÄGDEFRAU, K. (1973): Geschichte der Botanik. Stuttgart, Gustav Fischer.
SCHEUCHZER, J.J. (1723): Herbarium Diluvianum collectum. Petri Vander Aa, Bibliopolae, Civitatis atque Academia Typographi
SCHEUCHZER, J.J. (1726): Homo diluvii testis. typis Joh. Henrici Byrgklini.
Labels: 16th century, Alps, Ancient times, Botany, Fossil Legends, Geology, Geology and Society, Geomythology, Heretic geologists, Life as geologist, Paleontology, Stratigraphy, Swiss
Donate to History of Geology
Figure description
"Awful Changes." The caricature by De la Beche of Charles Lyell as Prof. Ichthyosaurus on the pages of Francis Trevelyan Buckland (Son of William B.). "Curiosities of Natural History".
May 8, 1902: La Pelée
" My Dear Sister: This morning the whole population of the city is on the alert and every eye is directed toward Mont Pelee, an extinct...
15 April, 1912: The Iceberg That Sank the Titanic
In the night of April 14, 1912 the passenger liner " R.M.S. Titanic " collided with an iceberg, two hours later (2:20, April 15) ...
The (possible) Geological Origin of the Minotaur Myth
According to myth the Minotaur was a terrible creature, born from an unnatural union between queen Pasiphaë of Crete and a sacred bull, sen...
Namazu: The Earthshaker
According to Japanese myth the cause of earthquakes is the giant catfish Namazu or Namazu-e (the second term refers to the woodcuts of Nama...
Historic tsunamis in Japan
Fig.1. Kanagawa Oki Uranami - "The Hollow of the Deep-Sea Wave off Kanagawa", coloured woodcut from the collection of "Thir...
Historic earthquakes in Japan
Japan is situated in the collision area of four great lithospheric plates : the Eurasian/Chinese Plate , the North American Plate , the Phi...
"It was nothing of this earth, but a piece of the great outside; and as such dowered with outside properties and obedient to outside l...
John Joly tracking Oldhamia
John Joly (1857-1933) was an Irish professor of geology, trained as engineer, who made important contributions to geology, mineralogy, geo...
The Granite Controversy: Neptunism VS Plutonism
The dominant role of Neptunism, denominated after the Roman god of the sea, in geology during the 18th and 19th century can be traced back ...
August 27, 1883: Krakatoa - The day the world exploded
"Perhaps, however, the most important evidence of what was actually going on at Krakatoa during the crisis of the eruption is that deri...
Accretionary Wedge #28: Have you ever danced with ...
The historical problems for women geologists: Trav...
History of Paleomammology: The Taphonomy of Hoplit...
Geology History in Caricatures: Exploring and Educ...
12 October, 2007: Rock fall at the Einser
9 October, 1963: Vajont
Forensic entomology - History and Archeology
5 October, 1905: T-rex and the birth and death of ...
The Granite Controversy: Geologists pilgrims
When pterosaurs were still mammals: evolving views...
14th century (3) 15th century (6) 16th century (15) 17th century (15) 18th century (36) 19th century (117) 20th century (106) 21th century (74) 23th century (3) A geologist riddle (25) Accretionary Wedge (9) Africa (16) Alps (49) Ancient times (50) Artwork (5) Asia (27) Austria (4) Boneyard (3) Botany (21) Cabinets of curiosities (6) Cartography (34) Cartoons and Earth Sciences (39) Cryology (28) Earth Science VS Pop Culture (185) England (34) Etymology (2) Europe (24) Exogeology (14) Expeditions (39) Field-Sketch (2) Forbes (2) Forbes Blog (19) Fossil Legends (28) France (10) Geo-Files (33) Geo-Quotes (1) Geological Catastrophes (79) Geological Maps (42) Geology (114) Geology and Society (226) Geomorphology (36) GeoMovies (9) Geomythology (42) Germany (17) Heretic geologists (124) Ice Age (19) Italy (44) Life as geologist (127) Mineral (10) Mineralogy (23) North America (35) Oceania (20) Paleoclimatology (18) Paleomammology (12) Paleontology (90) Prehistoric Monster Movie (10) Scandinavia (3) Schlockology (5) Scientific American Blog (6) Seismology (31) South Africa (3) South America (17) South Tyrol (20) Stratigraphy (74) Swiss (8) Tectonics (24) Today in Geohistory (54) Volcanology (51) Zoology (33)
View my complete profile.
History of Geology News Group
History of Geology on Twitter
This work is published under a Fair Use/ Creative Commons Licence - Content of other websites, movies, cartoons, papers, books and other entities mentioned or used herein are © to their respective owners, and used only for education/reference/ discussion purpose with reduced resolution/content. ©-holders can demand removial of content
A is for Aspirin
C6-H12-O6
Epiphenom
Genomics, Evolution, and Pseudoscience
Memoirs of a Defective Brain
Protein Evolution and Other Musings
Rule of 6ix
The Allotrope
The Astronomist
The Biology Files