A new study examined hundreds of Indohyus fossils—like the one seen above—found in mudstone in Indian-controlled Kashmir. (See a map of India).

The skull structure and the ear show that Indohyus was closely related to whales, the study team concludes.

Bu the structure and chemical composition of the teeth indicate that Indohyus was an herbivore, even though it's widely thought that the earliest whales took to the water in pursuit of fish.

"Clearly this is not the case," Thewissen commented. "Indohyus is a planteater and already aquatic. Apparently the dietary shift to hunting animals came later than the habitat shift to water."

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