Two species of rhinos are contenders for the title of rarest land mammal for different reasons ... Others on the critically endangered list include the African forest elephant, black rhinos ...

And a Red List of threatened species ... But she said populations of large land mammals were falling and “declining population is the trajectory to extinction.” ...

The story of whales’ evolution from land mammals is hidden in their genes. The oceans are thought to be where life started but about 50-million years ago, something incredible happened ...

Ambulocetus was a true marvel—a mammal bearing both the marks of its land-dwelling ancestors and the beginnings of a life at sea. Its name, meaning “walking whale,” perfectly captures its ...

Call it an unfinished story, but with a plot that's a grabber. It's the tale of an ancient land mammal making its way back to the sea, becoming the forerunner of today's whales. In doing so ...

An immense rhino that is a contender for the superlative of “largest land mammal of all time,” the huge herbivore roamed eastern Eurasia between 23 million and 34 million years ago.

Salamanders and the tuatara, a lizard-like animal that has lived on Earth for 225 million years, were the first vertebrates to walk and run on land ... animals such as mammals and birds.