SCIENTISTS have established that a fossil monkey found in an underwater cave in the Caribbean is a million years old.
And UCT scientist Robyn Pickering, from the university’s department of geological sciences, was one of the lead researchers in the team that pinpointed the date.
The monkey’s fossil tibia, or shin bone, was found embedded in limestone rock in an underwater cave in the Altagracia Province in the Dominican Republic.
An international team, which published their findings in the Journal of Human Evolution this week, said the bone belonged to a species of monkey, Antillothrix bernensis, that had lived in the region relatively unchanged for a million years.
The monkey was roughly the size of a small cat, was tree-dwelling and lived largely on a diet of fruit and leaves.
In order to find out how old the fossil monkey was, the researchers had to date the limestone in which the fossil had been found.
Pickering said scientists have been puzzled about the age of primate fossils found in this region since the days of Charles Darwin.
“The presence of endemic new world monkeys on islands in the Caribbean is one of the great questions of bio-geography and now knowing the age of these fossils changes our understanding of primate evolution in this region,” Pickering said.
“Our analysis of the fossils shows that Antillothrix existed on the island of Hispaniola for over a million years relatively unchanged morphologically.”
Pickering worked on the project at the University of Melbourne with Helen Green, using a isotope chronology laboratory where they measured the levels of uranium, thorium and lead in the limestone rocks today. With this data, they calculated the age of the fossil to be a million years.
UCT’s website says Pickering has worked mainly on cave deposits containing early human fossil remains.
Her interests lie in providing a precise chronology for evolutionary developments. She is currently working on early human cave sites near Johannesburg and those of Pinnacle Point on the southern Cape coast. – Staff Writer