As an undergraduate, I had an opportunity to go on a number of archeological digs. So I had experience excavating, digging up remains of ancient Indian villages in the Midwest and in the Southwest.

One has to devote oneself to a particular pursuit. To be successful at anything, you have to make a total commitment to it.

When the first fossils began to be found in eastern Africa, in the late 1950s, I thought, what a wonderful marriage this was, biology and anthropology. I was around 16 years old when I made this particular choice of academic pursuit.

One has to take initiative in life to achieve what he or she wants.

There have been some friendships lost over this. That's the most difficult for me. I find it very uncomfortable to know that I was at one time close friends with someone, and because of jealousies and misunderstandings and so on, these friendships have dissolved.

Evolution explains our biological evolution, but human beings are very unique creatures. As the Dobzhansky said, all animals are unique; humans are the uniquest. And that uniqueness of being human, language, art, culture, our dependency on culture for survival, comes from the combination of traditional biological evolution.

The right question to ask from a Darwinian prospective is what was it about bipedalism that was so advantageous? Why did it lead to a - why did that adaptation ultimately lead to a species Homo sapiens that has come to dominate the planet today with six and a half billion people?