Natural History Museum palaeontologists discovered the first evidence of a Miocene terrestrial fauna from Arabia in 1974. These fossils - ancestors of elephants, rhinos and giraffes - were found in eastern Saudi Arabia and dated about 19 million years old. Research into Arabia's Tertiary land faunas, carried out by Peter J. Whybrow, then continued along the eastern Arabian coast through the State of Qatar and in 1979, following a hint from oil company geologists, the first Arabian Late Miocene (c. 6-8 million years ago) continental fauna was discovered in the Emirate of Abu Dhabi.
Figure 1. Peter J. Whybrow, NHM (left) and Andrew Hill, Yale University examine a fragmented elephant tusk.
The fossil outcrops had previously been dated as 'undifferentiated Tertiary' - a catch-all date from 65 million years ago to 5 million years ago but the discovery of fragmented fossils of primitive horses and elephants provided a more accurate date for the rocks. These have now been named the Shuwaihat and the Baynunah Formations.
Figure 2. Cartoon of life in Abu Dhabi 8 million years ago.
The collection of fossilized aquatic freshwater animals shows that Abu Dhabi enjoyed a very different climate 6 to 8 million years ago. The fossils and the sediments of the Baynunah Formation provide evidence that a major river system once flowed through an area that is now arid sand and rock desert. The river was made up of numerous small channels, probably no more than three metres deep, but the entire river system was a braided network tens to hundreds of metres wide. This river may have been part of a larger system, the remains of which includes the modern Tigris and Euphrates rivers. A permanent flow of water existed in which freshwater mussels, catfish, turtles and crocodiles, and hippopotami lived. The fauna feeding from the plants living around the river system, a grassy-woodland environment - comprised rodents, including a new species of gerbil, six species of antelopes, giraffes, three species of primitive elephants and carnivores, such as hyaena and a lion-sized sabre toothed cat. This Late Miocene fauna from the Emirate of Abu Dhabi is unique and has not yet been found anywhere else in Arabia.
Figure 3. Coastal exposure of the fossiliferous Baynunah Formation, Emirate of Abu Dhabi.
It is likely that no single cause changed the past climate of Abu Dhabi to its present arid environment. A combination of mountain building in the Middle East together with changing ocean geography and shifts in climatic belts - especially the pattern of the annual monsoon - caused an increase in desertification from, at the latest, historical times.
The research in Abu Dhabi has been, and continues to be a multidisciplinary project in the Museum's Global Change and the Biosphere Programme. The Natural History Museum and Yale University team has been joined not only by specialist palaeontologists but also by specialists in carbon and strontium isotope studies, geochemists, stratigraphers, sedimentologists and magnetochronologists.
Figure 4. Gillian Comerford, NHM, starting excavation of the lower jaw of a primitive elephant.
In addition, colleagues who have undertaken similar studies on the Miocene terrestrial vertebrates of Africa and Asia have contributed their expertise. These studies show that the Arabian Peninsula was the 'cross-roads' at which diversification, and probable re-invasion, of animals between Africa and southwestern Asia occurred during the Miocene. Animals probably used the Ethiopian-Yemen isthmus and the ephemeral Miocene land connection across the Arabian Gulf to 'migrate' to and from Africa and Asia via Arabia.
The Natural History Museum's research in the United Arab Emirates continues until the year 2000 and is supported by the Abu Dhabi Company for Onshore Oil Operations. The project titled 'Arabia's Past and Present Environments' is part of the Natural History Museum's 'Global Change and the Biosphere' research programme.
This project is part of the Ecological Patterns and Processes Research Theme.
For further information contact:
Peter J Whybrow
Department of Palaeontology
The Natural History Museum
Cromwell Road
London SW7 5BD UK
Tel: +44 (0) 171 938 9283 Fax: +44 (0) 171 938 9277
Email: pjw@nhm.ac.uk
