New Research Tracks the History of Manatees Across Earth's Oceans
Published:31 Aug.2022    Source:ScienceDaily

Zoologists refer to manatees and dugongs as "sea cows" but a simple internet search might return the more playful moniker "floaty potatoes." While only four species of the round, slow-moving aquatic herbivores of the order Sirenia remain on Earth -- and all are considered vulnerable to extinction -- fossil evidence suggests that many different kinds of sea cows lived in the past, and at times numerous species coexisted. Over their long history sea cows have lived along the coasts of every continent but Antarctica.

A new paper appearing today in the open access journal PeerJ has assembled the most complete story yet of these unique creatures' ancestry. The researchers say the highest diversity of sea cow lineages occurred around 22 and 16 million years ago. But over the past 9 million years, the number of lineages has dropped precipitously resulting in the few species that remain today.