With tens of thousands of fish species and a majority of aquatic habitats yet to be observed, fish are also one of the most vast and mysterious animal classification groups on our planet ...

The latest research suggests that echidnas and platypuses originate from an aquatic ancestor, rather than a terrestrial one, ...

A vast proportion of our oceans still remain unexplored and mysterious, with unimaginable diversity calling them home.

Its neck vertebrae are shorter, giving it a less flexible, more stable neck -- an adaptation for swimming also seen in other aquatic animals such as sea cows, and in an extreme form in modern whales.