The BBC's Natural History Unit focuses on the planet's most advanced animal, beginning with a look at how man communicated before the evolution of language. Some gestures and expressions are so ingrained that we have not been able to erase them from our vocabulary.

This episode looks at our most fundamental activity - finding food, examining how humans exploit even the most inhospitable environments, and analysing how our origins as hunter-gatherers manifest themselves in the fast-food culture of the modern world.

In evolutionary terms, the human animal has gone from mud hut to skyscraper in the mere twinkling of an eye. The cameras of the Natural History Unit capture the subtleties of human hierarchy in an English pub, the urge to set up and defend territory in a Tokyo park, and tribal behaviour as displayed by gangs in Los Angeles.

In this program, Desmond Morris analyzes the biological nature of love, with its attendant patterns of behaviour and signals of health and fertility that have evolved to ensure pair-bonding and genetic survival. The pre- and post-pubescent periods of sexual maturation, the stages of courtship, and the aesthetics of physical beauty are studied, along with the anatomical mechanics of sexual arousal and copulation. In addition, the stresses placed on couples by life in an urbanised, crowded world are explored.

Desmond Morris looks at the natural history of the human parent and child. Why do homo sapiens devote more time to raising their young than any other animal? What makes parents sacrifice so much for their children, and why, once the offspring have been raised, don't humans simply die off as other creatures do? Desmond reveals how children offer a way of overcoming death itself.

Humans are animals with similar biological needs to other species. So why have we got art, cinema, sport, literature and philosophy? In the last programme in the series, Desmond Morris examines what the human animal does when it has sorted out its basic needs - food, warmth and shelter - and has gone beyond mere survival. He explores the inventiveness of human behaviour, and comes to some fascinating conclusions.