South African and French Researchers team up to excavate in the Cradle of Humankind to understand our evolution

Paleobiodiversities and paleoenvironments during the Plio-Pleistocene at Bolt’s Farm: A multidisciplinary approach

CONTEXT

The Pliocene (5.33 to 2.58 Ma) is considered to be a generally warm period during which the El Niño phenomenon appears to be permanent. Some comparisons have been made with current global warming. However, a distinction should be made between two phases during the Pliocene: the earliest, despite a few oscillations, saw a virtually constant warm climate, and the most recent was marked by a gradual cooling, corresponding to the Plio-Pleistocene Transition (PPT), at around 2.7 Ma, which continued with the major climatic oscillations seen in the Pleistocene. These climatic changes will affect environments and biodiversity.

It was during this geological period that pre-humans (such as australopithecines) and the first humans diversified, mainly in East Africa where numerous fossils have been discovered in the Great East African Rift. This is particularly true of the famous Lucy, discovered in 1974 in Ethiopia. However, another region of Africa is proving just as important for research into our origins: Southern Africa. It was in 1924 that the first pre-human not belonging to our genus (Homo) was identified. It was a juvenile specimen from the Taung quarries in South Africa, the holotype of Australopithecus africanus. Since then, a large number of discoveries have been made in South Africa, at various karst sites with fillings dating from the Plio-Pleistocene (4.5 to 0.9 Ma). Most of these sites, the best known of which is Sterkfontein, are located in the Cradle of Humankind area, classified as a World Heritage Site by UNESCO in 1999.

OBJECTIVES

Apart from the Bolt’s Farm fossiliferous area (which corresponds to a vast karstic network located in the Cradle of Humankind) where the researchers are conducting their field studies, there are no deposits in southern Africa that would allow a longitudinal study of environmental changes and the evolution of biodiversity to our knowledge. The other sites in the region only have deposits that have accumulated over a much shorter geological period. More than 30 sites have been recorded at Bolt’s Farm. The ages of the fossiliferous deposits at Bolt’s Farm range from around 4.5 Ma to 0.9 Ma. They are therefore dated from the Lower Pliocene to the Middle Pleistocene Transition (MPT). To better understand this Plio-Pleistocene Transition (PPT), we need to understand the characteristics of the palaeobiodiversity and palaeoenvironments that existed before, during and after it. These results will enable us to understand the environmental context in which the first South African pre-humans and humans lived and how the current biodiversity of southern Africa came into being. The same applies to relations between Southern Africa and East Africa, in particular when these exchanges of biodiversity (including our ancestors) took place and in what direction.

TEAMS

This project was initiated thanks to funding from the Partenariat Hubert Curien (PHC) PROTEA bilateral program between France and South Africa. It enabled the pooling of skills by the French and South African partners specializing in geoscience at the international level. The project has a multidisciplinary approach and is a consortium involving three French partners and two South African partners.

On the French side, CR2P (Centre de Recherches en Paléontologie-Paris – CNRS (Centre National de Recherche Scientifique), MNHN (Muséum national d’Histoire naturelle) and SU-FSI (Sorbonne Université – Faculté des Sciences & Ingénierie)) is the French lead partner in the project and this laboratory specialises in palaeontology, ISTeP (Institut des Sciences de la Terre de Paris – SU-FSI and CNRS) is a geology laboratory and IMPMC (Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie – SU-FSI, CNRS, MNHN & IRD (Institut de Recherche pour le Développement)) is involved in understanding fossilisation phenomena.

On the South African side, the Department of Zoology (Faculty of Sciences, University of Johannesburg – UJ) is the South African sponsor of the project and is involved in palaeontology and student training, while the DNMNH (Ditsong: National Museum of Natural History, Plio-Pleistocene Palaeontology section) is the repository for the collections.

Fieldwork at Bolt’s Farm is covered by two excavation permits issued by SAHRA (South African Heritage Resources Agency) and held by N. Vilakazy (UJ), L. Kgasi (DNMNH) and D. Gommery (CR2P).

ABOUT THE PHC PROTEA PROGRAMME

For the last 27 years the Partenariat Hubert Curien (PHC) PROTEA programme has supported over 200 projects between French and South African researchers. This bilateral cooperation programme is open to all scientists and academics from both countries and promotes the mobility of researchers from their scientific communities. Each year, 16 researchers – 8 South African and 8 French – are paired to undertake 8 joint projects from a wide spectrum of scientific fields and granted access to equal financial support and research training capacities over a duration of 2 years.

PHC PROTEA is implemented in France by the Ministry of Europe and Foreign Affairs (Ministère des Affaires étrangères français – MEAE) and the Ministry of National Education, Higher Education and Research (Ministère français de lʼEnseignement supérieur, de la Recherche et de lʼInnovation – MESRI), and in South Africa by The National Research Foundation of South Africa (NRF).