There's nothing magical about the number, yet five digits at the end of their limbs is a motif that runs through all the animals with four limbs, called tetrapods. Even when there are fewer than ...

Cladistics is one way scientists classify organisms. A cladogram shows the nature of evolutionary relationships that may have occurred, similar to a family tree. You will make a cladogram in this ...

Cladogram: a branching diagram that represents only phylogenetic relationships among organisms (i.e., it does not include geological age or other contextual information). Formally, a cladogram is ...

The sequencing of the platypus genome has received a high amount of misleading press attention. What does this information really tell us about this strangely unique animal and its genetic past?

About 400 million years ago fish began to go on to the land and eventually changed into tetrapods - animals with four limbs. Now scientists are studying a "weird" species of fish, the sea robin ...

The authors believe this finding indicates that the ancient animal must have developed this trait long before it reached land. "The thing that really stuns me is that every innovation, every invention ...