In a few cases, amber has preserved spiders' egg sacs and webs, occasionally with prey attached; the oldest fossil web found so far is 100 million years old. Earlier spider fossils come from a few lagerstÃ¤tten, places where conditions were exceptionally suited to preserving fairly soft tissues.
Definition of METATARSAL. : of, relating to, or being the part of the human foot or of the hind foot in quadrupeds between the tarsus and the phalanges that in humans comprises five elongated bones which form the front of the instep and ball of the foot. See metatarsal defined for kids.ADVERTISEMENT. of, relating to, or being the part of the human foot or of the hind foot in quadrupeds between the tarsus and the phalanges that in humans comprises five elongated bones which form the front of the instep and ball of the foot. See metatarsal defined for kids. ADVERTISEMENT.
The metatarsals are the bones that make up the main part of the foot in humans, and part of the leg in large animals or paw in smaller animals. The number of metatarsals are directly related to the mode of locomotion with many larger animals having their digits reduced to two (elk, cow, sheep) or one (horse).t is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made up of one or more segments or bones, generally including claws or nails.