Information AboutQuadrupedal |
| CATEGORIES ABOUT QUADRUPED | |
| tetrapods | |
| locomotion | |
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QUADRUPEDS AND TETRAPODS Not all four-limbed animals are quadrupeds. Although arms and wings are, in the evolutionary sense, modified legs, four-limbed animals are in fact classed as Tetrapod s – members of the Taxonomic unit '' Tetrapoda ''. These include all Vertebrate s with quadrupedal ancestors, including Mammal s, some Reptile s, Amphibians , and Bird s. The distinction between quadrupeds and tetrapods is important in evolutionary biology, particularly in the context of Biped s, winged animals, and animals whose limbs have adapted to other roles (e.g. Fin s, in the case of Cetaceans and Pinniped s). All of these animals are tetrapods, but none are quadrupeds. Even Snake s, whose limbs have become entirely Vestigial , are nevertheless tetrapods. QUADRUPEDALISM IN HUMANS In July of 2005 , in rural Turkey , scientists discovered five Kurd ish siblings who had learned to walk naturally on their hands and feet. Unlike Chimpanzee s, who ambulate On Their Knuckles , the Turkish Siblings (ranging from 18 to 34 years old) walked on their palms, allowing them to preserve the dexterity of their fingers. Callouses found on their hands make the possibility of a hoax unlikely. Another similar case has been reported in Chile, but the case is still being investigated and reports are not released as of March 22, 2006 . The discovery of the family has provided scientists a unique view into human evolutionary history. Nicholas Humphrey, a researcher from the related to Cerebellar Ataxia , have regressed to an earlier stage of human evolution, and have simply continued to walk "as infants" into adulthood. Other scientists, such as Stefan Mundlos of the which is responsible for human Biped alism. He speculates that the Turkish siblings lack this gene. |
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