Hi, it's Alice.

What is the human?

Is it us who can talk and think,

see film, touch buttons and things?

Or is a human something much more basic?

That's Richard Leakey, one of the most important contributors to the field of paleoanthropology, the study of human origins.

The Academy of Achievement has quite a collection in its audio archive

of interviews with renowned fossil hunters, as they are colloquially called,

before we dig in deeper with two of them, pardon the pun,

we'll listen for a few minutes to a montage of some of these folks,

people who have spent their careers looking for answers to who we are and how we got here.

Clearly, it's much more to being human than simply having a large brain that is capable of emotion and thinking. And sympathy has been introduced

as part of the religious faith that this is what makes us special. We have that capacity to

judge right and wrong good and bad evil and

virtue and all of these complicated concepts that we've developed but can one

really say that elephants don't have basically the same criteria and make up of

emotions? And I'm very impressed by a lot of animals that show not only sympathy with members of their own species but show empathy

and being able to interact with other species in a helpful way when it's appropriate.

And I think the most fundamental question about humanity is that we walk on two legs.

And walking on two legs is enormously important because if we were using our hands for support,

we couldn't manipulate things with tools and the development of

bipedalism is I think the start of the human story and it probably goes back to

...