A staff of cave divers and scientists have uncovered a brand new cache of extinct monkey fossils submerged deep throughout the underwater passages of a Caribbean cave.
Forty years in the past, only some well-preserved stays of New World monkeys had been discovered on the Caribbean islands of Hispaniola and Jamaica, but it surely was sufficient to trace at a lacking patch of primate evolutionary historical past.
Considered one of these fossil species was the Hispaniola monkey (Antillothrix bernensis), recognized solely through an ankle bone and some bits of damaged jaw.
However with enhancements in cave diving security and expertise, researchers have probed deeper into the islands’ flooded cave methods since 2009, with the primary A. bernensis cranium present in 2011. These submarine caverns, vital to the indigenous Taíno folks, are studded with “remarkably well-preserved” fossils which have lain there for millennia, shielded from the jostling of waves and animals.
The newest finds, out of the Cueva Macho cave system, on the Dominican Republic facet of Hispaniola, add new element to our understanding of the extinct species.
“The number and quality of the Antillothrix crania outlined in this paper allow us to describe the skull completely and understand variation between individuals,” says Johns Hopkins College paleobiologist Siobhán Cooke. “This can tell us about the diet and social systems of these animals.”
4 new skulls had been discovered within the cave, together with three new mandibles. With these new items from the Cueva Macho system, in addition to an grownup mandible present in an analogous cave referred to as Padre Nuestro, your complete Antillothrix bernensis species is now represented by seven near-complete crania, two maxillae fragments, an occipital fragment, 5 full mandibles, and dozens of different non-skull bones.
It would not sound like a lot to go off, however this assortment – particularly the skulls – goes a good distance in describing the monkeys’ measurement, food regimen, intercourse variations, even social lives. And that is extra element than we have now for every other Caribbean monkeys.
“These new specimens, in combination with those previously described, will allow for a detailed study of population- and species-level variation, an exceedingly rare opportunity for any fossil primate,” the authors write of their paper.
By analyzing the fossils, the researchers estimate that men and women had been of an analogous measurement, as much as 3.4 kilograms (round 7 kilos), which suggests mating wasn’t overly aggressive, and that they might have lived in small monogamous household teams with younger relying on their mother and father.
Their rounded tooth, with small canines, would have suited a food regimen of fruit, just like the fashionable South American titi monkeys, which have comparable bodily options. And so they seem to have had no knowledge tooth, which is uncommon amongst primates.
It is a thriller how these monkeys obtained contained in the caves all these years in the past, however primarily based on injury to the jaw fossils, Cooke suspects it was not by selection.
“It could be possible that a now extinct owl, which would have been quite large, caught these monkeys and brought them into the cave where it was living –rather than the monkeys falling in at random,” she says. “Owl feeding deposits are not uncommon in Hispaniolan caves.”
The Hispaniola monkey grew to become extinct throughout the final 10,000 years, but it surely’s unclear simply what drove this species below.
“These fossils help us to better understand the anatomy of Antillothrix, which can help us identify ecological factors that might have predisposed it to extinction… [and] ultimately guide policy for preserving the remaining mammalian diversity on the Caribbean islands and elsewhere ” says Cooke.
This analysis was revealed in Journal of Human Evolution.
