ROOTSTOWN, Ohio, Dec. 20 (UPI) -- A researcher in Ohio says the missing link between whales and their four-footed ancestors was a fox-sized mammal that looked something like a miniature deer.
Hans Thewissen, a professor at Northeastern Ohio Universities Colleges of Medicine and Pharmacy, and colleagues discovered the skeleton of Indohyus, an approximately 48-million-year-old even-toed ungulate, in the Kashmir region of India.
Thewissen reported in the journal Nature that it is closest known fossil relative of whales, the university said Thursday in a release.
The report said it appears the bones of the skeleton of Indohyus had a thick outside layer, much thicker than in other mammals of this size. This characteristic is often seen in mammals that are slow aquatic waders, such as the hippopotamus today.
The report said Indohyus' aquatic habits are further confirmed by the chemical composition of their teeth, which revealed oxygen isotope ratios similar to those of aquatic animals. All this implies that Indohyus spent much of its time in water, researchers said.
