Morgan has pointed out that other hairless land-based species such as the elephants and the rhinoceroses also have aquatic ancestors, the main exception being the naked mole rat which lives underground.

This also makes it less likely that an aquatic ancestor would have the evolutionary potential to give rise to all the different forms and species of insects that we know today.

The specific aquatic ancestors of the tetrapods, and the process by which land colonization occurred, remain unclear, and are areas of active research and debate among palaeontologists at present.

All dragons species descend from an aquatic or semi-aquatic ancestor.

But other biologists have argued that the real aquatic ancestor of amphibians, reptiles, mammals, birds and people is the lungfish, whose gills are supplemented with primitive, air-breathing lungs.

Built to survive harsh conditions, extremes of temperature, long droughts, and competing for scarce food supplies, these elephant-sized multi-tentacled creatures are far more physical and aggressive than their aquatic ancestors.

X chromosomes in humans clearly exhibited non-gene DNA traces of a distant aquatic ancestor, a kind of dolphin.

Yes, an aquatic eel-like ancestor, in fact.

Like most fish today, our aquatic ancestors had noses that were just holes above their mouths through which water could flow.

Eviku, who descended from aquatic ancestors, was also doing his part to survey the lake, but he couldn't dive as deep or last as long without oxygen as she could.