Evolution Diary

A new species of extinct pygmy sea cow (illustrated above with skull inset) is one of the first fossil mammal species found in Madagascar from the mysterious time period between 80 million years ago and 90,000 years ago, experts say.

“There’s a big gap where we really don’t know anything about what’s going on in the fossil record,” said study leader Karen Samonds, of McGill University in Montreal, Canada.

Sea cows, or sirenians, today include manatees and dugongs.

Known from a roughly 40-million-year-old skull and a few ribs, the new species has been named Eotheroides lambondrano, after the Malagasy word for dugong, which translates to “water bushpig.” At about seven feet (two meters) long, the ancient pygmy sea cow was smaller than the modern dugong, which ranges from about 8 to 10 feet (2.4 to 3 meters) in length.

The pygmy sea cow would have been “a neat in-between” animal in the evolution from primitive land-dwelling mammals to today’s aquatic sea cows, Samonds said.

E. lambondrano is also unique in that its closest relatives would have lived in what is now India and Egypt, according to the study—making its Madagascan location all the more special.

“This fossil gives us a new glimpse not just at a new time period, but at a new place,” said Samonds, whose work was funded in part by the National Geographic Society’s Committee for Research and Exploration.

“Madagascar already has a lot of strange beasts, and we now have a glimpse of this species from so far away.”

News from National Geographic

Findings published December 12 in the Journal of Vertebrate Paleontology.