8m-year-old monkey fossil found in Abu Dhabi

The discovery provides important clues as to when and how old world monkeys dispersed out of Africa and into Eurasia.

An international team of scientists and Abu Dhabi Tourism and Culture Authority (TCA Abu Dhabi) have announced the discovery of a 6.5 to 8-million-year-old fossil monkey specimen from Shuwaihat Island in Abu Dhabi’s Western Region (Al Gharbia).

A team sifting sand for the remains of the tiny animal fossils at Shuwaihat in 2009. — Photo by Mark Beech

The discovery, announced in the current issue of Proceedings of the National Academy of Sciences, USA, is providing important clues as to when and how old world monkeys dispersed out of Africa and into Eurasia. The scientists, some of whom who are involved in field discovery, are from Hunter College-City University of New York (CUNY), the Berlin-based Museum für Naturkunde and Yale University as well as TCA.

“We know that old world monkeys also originated and migrated out of Africa millions of years ago, but until now, it has been unclear as to exactly when and how,” said Dr Chris Gilbert, lead author of the study.

Old world monkeys are a diverse and widespread group, which include African and Asian macaques, baboons, mangabeys, leaf monkeys and langurs. These monkeys, according to the study, are the most successful group of living non-human primates and although found throughout Africa and Asia today, their dispersal out of Africa and into Eurasia has never been fully understood.

“It takes years of work to make such discoveries and study them,” said TCA’s Dr Mark Beech, a study co-author.

He is a senior Abu Dhabi-based scientist who has been involved in many major discoveries, particularly in Abu Dhabi’s Al Gharbia (Western Region). He has worked on many important sites in the Emirate and made major discoveries.

“The discovery of a tree-dwelling guenon monkey in the Abu Dhabi desert highlights the vast ecological changes that have taken place in the Arabian Peninsula,” said Dr Beech, who is also an old resident of Abu Dhabi.

According to scientists, previously it was thought that some of the monkeys, particularly macaques, may have dispersed into Eurasia over the Mediterranean Basin or Straits of Gibraltar around six million years ago, during the Messinian Crisis when the Mediterranean Sea dried up, allowing animals to cross between North Africa and Europe.

“These fossils indicate that, instead, old world monkey dispersal could have taken place through the Arabian Peninsula even before the Messinian Crisis,” Dr. Gilbert explained.

The fossil, a very small lower molar, was discovered in 2009 and since then it has been under study and scientific research. The team determined that the tooth belonged to the earliest known guenon, which are some of the most brightly coloured and distinctive monkeys in modern African forests.

“When we found it, we were doing back-breaking sieving work searching for remains of tiny fossil rodents,” said Dr Faysal Bibi of Berlin’s Museum für Naturkunde, a study co-author and discoverer of the little molar.

“We spent many days over consecutive years sieving through tonnes of sand at this one site. It paid off,” said Bibi.

Previously, the oldest known guenon fossil was approximately four million years old.

“Our specimen pushes back the first appearance of the group by at least 2.5 million years, and most probably more,” said Professor Andrew Hill of Yale University, another co-author on the study.

The Historic Environment Department of TCA Abu Dhabi has a strategy to preserve, protect, study and promote the internationally important fossil sites found in Al Gharbia. A team of UAE specialists from the Historic Environment Department has been working closely since 2006 with a team of experts from Yale University and other renowned institutions to coordinate the research, study and publication of these fossils.

“The preservation of the Late Miocene fossil sites in Abu Dhabi Emirate is of paramount importance,” said Mohammed Amer Al Neyadi, Head of the Department at TCA.

He said it was essential that these sites be protected to further “our understanding of the ancient fossil record”.

The team stresses that future work in Abu Dhabi and the Arabian Peninsula is critical to shedding further light on the evolutionary history of monkeys and other mammalian groups. Previous work in the region has also highlighted interesting aspects of elephant evolution.

“We still know relatively little about ancient life in the Arabian Peninsula. A rare find like this is a ‘first’ for the entire region,” said Dr Bibi.

nissar@khaleejtimes.com

• UAE