What is it that really makes us, us? It's our collective intelligence. It's our ability to write things down, our language and our consciousness.

What the fossil record does do is to force us to contemplate our place on the planet. We are but one species of several hominids that inhabited Planet Earth, and like our distant cousins who went extinct fairly recently, our time on Planet Earth is also finite.

With the discovery of Zinjanthropus at Olduvai Gorge in 1959, my grandmother Mary Leakey pioneered the research in East Africa with my grandfather Louis. Many more spectacular fossil finds have since been made, both in Africa and elsewhere, by many researchers driven to understand our past.

If you want to become a fossil, you actually need to die somewhere where your bones will be rapidly buried. You then hope that the earth moves in such a way as to bring the bones back up to the surface. And then you hope that one of us lot will walk around and find small pieces of you.