Fossils reveal the lifestyle of an extinct Caribbean monkey

Researchers have revealed fascinating new information about the extinct Caribbean monkey, Antillothrix bernensis, thanks to the discovery of rare, well-preserved fossils in the Dominican Republic.

The fossils were analyzed by a team of experts at Johns Hopkins University School of Medicine.

The research offers a deeper understanding of the anatomy and ecological history of these long-extinct primates.

Extraordinary monkey fossils

This extraordinary find at the Cueva Macho fossil site has made it the most significant source of primate fossils on Hispaniola, the Caribbean island shared by Haiti and the Dominican Republic.

Dr. Siobhán Cooke is an associate professor of functional anatomy and evolution at Johns Hopkins University School of Medicine.

“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,” said Dr. Cooke.

“These data can ultimately guide policy for preserving the remaining mammalian diversity on the Caribbean islands and elsewhere.”

Looking into the Caribbean monkey’s past

The study, published in the Journal of Human Evolution, suggests that Antillothrix bernensis likely went extinct within the last 10,000 years.

Dr. Cooke and her team first uncovered the fossils in 2009, with additional discoveries made in collaboration with the Dominican Republic Speleological Society.

By 2018, the latest fossil findings were unearthed, providing a rare opportunity to study a larger collection of South American and Caribbean primates. These fossils are now housed at the National Museum of Natural History in Santo Domingo, Dominican Republic.

“The number and quality of the Antillothrix crania outlined in this paper allow us to describe the skull completely and understand variation between individuals. This can tell us about the diet and social systems of these animals,” said Dr. Cooke.

She further note that obtaining a large collection of South American and Caribbean monkey fossils is rare. The only other recorded instance of a comparably large sample is the extinct South American monkey, Homunculus patagonicus (an animal that lived in Patagonia).

Lifestyle of the extinct monkey

Using virtual three-dimensional models, the experts were able to thoroughly study the fossils. Antillothrix bernensis was monomorphic, meaning the males and females were about the same size, weighing up to five pounds.

“This indicates that there was little competition for mates among males. They may have lived in small family groups consisting of a female, male, and dependent offspring,” noted Dr. Cooke.

The research suggests that their diet consisted mainly of fruits, inferred from the rounded teeth and relatively small canines.

Interestingly, Antillothrix might have a contemporary relative, the South American Titi monkey. With its short canine teeth and weighing just over two pounds, this monkey offers the closest glimpse of what the extinct Hispaniolan monkey may have looked like in the wild.

How did the monkeys end up in a cave?

The mystery remains as to how several of these tree-dwelling primates ended up at the bottom of a cave approximately 10,000 years ago.

Dr. Cooke offers a potential explanation: predation by a now-extinct owl. Injuries evident in the jaw fossils of the monkeys suggest owl attacks.

Fossils missing portions of their jaws align with owls’ preference to consume the masseter, a major muscle attached to the jaw, leading to the theory of owls transporting monkeys back to caves.

“When owls feed, they will sometimes preferentially consume the masseter, a major muscle attached to the jaw, and these injuries are consistent with that,” explained Dr. Cooke.

“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.”

Unique window into the past

Ultimately, this study unlocks a unique window into the past, offering invaluable information about the extinct species that once called the Dominican Republic and Haiti home.

“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,” said the researchers.

The study is published in the Journal of Human Evolution.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–