The leader of this expedition is called Dr Bonnie Jacobs. She is a paleobotanist, which means that she studies fossils of plant life, not animal life. She is the chairperson of the Environmental Science programme at a US university. She has done research at other sites in Africa too.

She has found that plant leaves change depending on the amount of rainfall - they change size and shape. By finding out more about what plants looked like 46 million years ago, and what the climate was like, they can test computers that try to predict what might happen to our climate in the future.

This is very important for learning how to look after our environment, so that we can continue to grow food for ourselves.

Here is a photo of others in the group.

Seated in front (L to R): Gregg Gunnell, Ferdinand Mizambwa, Frank Kikwa (driver), Gregory Mkude (driver).

Standing (L to R): Metteio Macarios (cook), Kent Newman, Beth Kowalski, Jason Head, Pat Herendeen, Charles Msuya.

(Dr Bonnie Jacobs, who leads the expedition, took the photo)

Kent Newman is a fossil preparator in a Museum of Paleontology.

Patrick Herendeen is a paleobotanist from another university.

Gregg Gunnell is a vertebrate paleontologist from another university.

Jason Head, Beth Kowalski, Charles Msuya are graduate students (that means they are still studying but have got one degree already)

Ferdinand Mizambwa is a researcher from the Tanzanian Antiquities Unit.