This is a great introductory book if you're interested in anthropology, but have little or no formal training in the field. Richard Leakey is the son of Arthur Leakey (the renowned). This book is written on a level such that any educated lay person can appreciate and assimilate the concepts conveyed.
Leakey writes about what the first humans might have been like. There's a very interesting section on the evolution of bipedalism. Leakey sides with the group that theorizes that bipedalism freed the hands to perform tasks and carry children. Others argue that bipedalism arose as a more efficient means of locomotion. The jury's still out, you'll have to decide for yourself.
There are also interesting chapters on early hunting, art, language development and the origin of the mind. Te study of human evolution is a science fraught with speculation and there is often disagreement among experts. I guess the like is true in all scientific disciplines, but anthropology seems to be worse than many other disciplines. I'm sure it's just the nature of the field, i.e. putting the pieces together thousands to a few million years later with no witnesses or hard evidence to cling to.
This is a great book and a quick and easy read.