Hawaiian monk seals on the beach. There are only about 1,000 of them left. And they now have a new name. (Photo: AP Photo/The Garden Island, Dennis Fujimoto)
According to a new study published yesterday in the journal Zookeys, the history of the Caribbean monk seal is a little more complicated than scientists once thought it was once thought. In fact, as of yesterday, there's a whole new genus for it — the first such change in the biological classification of seals in about 140 years.
And here's what makes this discovery all the more important are the implications it holds for the survival of the monk seal as a whole.
Here's what happened:
There used to be three types of Monk seal: the Caribbean, the Hawaiian and the Mediterranean. While the Caribbean seals are believed to have been extinct since the early 1950s (the last time one was seen was in 1952), the Hawaiian monk seal (Monachus schauinslandi) and the Mediterranean monk seal (Monachus monachus) still exist. Until now, all three seals were thought to be more or less the same, biologically speaking. After all, scientists believe that the species were once all one, but they split off from one another when they separated geographically about 6.3 million years ago, and that the Hawaiian and Caribbean monk seals split off from each other later, about three or four million years ago.
Well, each of those major splits turn out to have been more severe than first thought. The study found that the Caribbean monk seal and the Hawaiian monk seal are so different from the Mediterranean monk seal, they deserve their own genus — so they've dropped the "Monachus" in their scientific names for the differentiating "Neomonachus." Hawaiian and Caribbean monk seals have narrower skulls and longer snouts than the Mediterranean kind. Researchers studied DNA from all three types of monk seal and found that, sure enough, those surface differences go deep into their DNA, and that the Caribbean and Hawaiian seals were more closely related on a molecular level.
If that doesn't sound like a big deal — well, you're probably just not hanging around in the right circles. For scientists, it's huge.
“In seals, sea lions and walruses that are just so well studied, this is just something that doesn’t really happen,” Kris Helgen, a zoologist at the National Museum of Natural History and a co-author on the study, told Smithsonian.com.
The two living species of monk seal are critically endangered. There are only about 1,000 Hawaiian monk seals and no more than 450 Mediterranean monk seals in the wild. Dwindling populations are the result of ocean pollution, destruction of natural habitats and fishing equipment that all-too-frequently ensnares seals in the ocean. The hope is that this discovery can help with their preservation.
"Scientists have long understood that monk seals are very special animals," said Helgen. "This study is exciting because it gives us a clearer view of their evolution and provides us with new context that highlights the importance of conserving these remarkable and endangered seals."