Question

The diagram shows the leg bones of a (Left -> Right): Orangutan, dog, pig, cow, tapir, and horse. Most of the animals have the same bones, although some are shaped differently and placed in different positions.

What does this suggest about mammals?

Answer 1

All the mammals have a common ancestor and evolved differently due to circumstances and areas.

Answer 2

The legs of different organisms such as a dog, pig, cow et cetera are made up of the same set of bones and thus, they have similar internal structure, however, they have evolved to have different shapes and positions.

Thus, they are the set of homologous organs.

Hence, all the above organisms have evolved from the common ancestors as all share the same set of bones.