Homologous structures refers to the similarities in the anatomy of the forelimbs of mammals that derive from different species, yet function differently for each mammal. It is said that these similarities in structure is because the mammals share DNA from a common ancestor. The forelimbs that are continuously compared are of those of a human, dog/cat, whale, and bird. In this photo, a human arm and cat leg are compared. If the bone structures were examined, then it can be seen that they both have a humerus, a radius and ulna, carpals, metacarpals, and phalanges. However, the human's forelimb is used to perform activities like lifting. The cat, on the other hand, would utilize its forelimb for walking or running.
No comments:
Post a Comment