Hard to resist the headline, “Enormous underwater fossil graveyard found,” from the National Science Foundation. The NSF posts a video detailing the discovery of an underwater cave system containing “hundreds of potentially 1,000-year-old [lemur] skeletons…” in Madagascar. As a paleontologist, hearing about the discovery large numbers of ancient skeletons is musical, like hearing Love This Giant or the new T Swift for the first time.
It’s a pretty remarkable discovery – hundreds if not thousands of bones representing many complete skeletons of various extinct lemur species. And toward the end of the clip is a skull of a pretty badass looking big cat. The video shows piles of loose bones dredged up from the cave. These will reveal lots of information about the biology of these recently extinct animals, especially if researchers can keep associated bones together.
So what are these animals? Lemurs are one of the most primitive living types of primates – although they are relatively closely related to us humans, they retain many characteristics of ancestral mammals. I know it’s hard to believe this aye-aye here is more closely related to you than to rodents, but it is:
Lemurs are found only on the island of Madagascar, and over the past several millions of years they have diversified into the roughly 100 species inhabiting the island today. But even just a few thousand years ago, there were more kinds of lemurs. This includes Megaladapis, the large-bodied “koala lemur,” and Hadropithecus, whose skull bears a striking resemblance to the extinct hominin Australopithecus boisei. As Laurie Godfrey says in the video, “two thirds of the animals that lived there only a thousand years ago are gone.” Humans are probably largely responsible for the extinction of many Malagasy lemurs in both the past and especially the present.
Much of the ‘fossil’ record for lemurs is recent by fossil standards, and so most specimens haven’t become fully fossilized. As a result, lemur paleontology is besprinkled with the term “subfossil,” indicating bones that are really old and belong to extinct animals, but don’t fit the technical definition of fossils. The lemur subfossil record has taught us a lot about the evolutionary history, adaptations, and recently even genetics of this primitive group of primates, as well as about the ecological history of Madagascar. It will be very interesting to see what new insights will come from the recently discovered scores of underwater skeletons.
OH NO IT’S HADROPITHECUS
(Figure 3 from Ryan et al., 2008. Scale bar is 1 cm)