Classic Attenborough: The Trials of Life

Birth is the first dangerous step into a hazardous world, an event which reflects the lifelong labours to come. From egg-laying to live-bearing, animals employ an extraordinary variety of techniques to disperse their offspring.

From creches of bats to elephant babysitters, from chimpanzee games to protective lacebugs - nature's answers are as varied as those in human societies.

The vital quest for food opens up an intriguing world of ploy and counter-ploy, exploitation and theft. Hungry animals find leaves defended by poisons, and seeds protected by spines and armour. But animals fight back with some tricks of their own including langurs that tiptoe through menacing thorns, macaws that have found a soothing medicine and 'criminals' who turn to breaking and entering.

Every conceivable trick is used by hunter and hunted - traps and lures, warnings and deception, ambush and camouflage. An orchid turns out to be a predatory flower mantis. Caterpillars look like snakes. In Patagonia, killer whales ambush sea-lions in the surf. These desperate battles between assassins and their victims have sharpened the skills of both in the art of pursuit and evasion.

Sir David looks at how creatures find their way around the earth with an accuracy that man has only recently achieved. Some creatures use echolocation to navigate, including river dolphins, while others, such as the electric eel, use electric fields. The albatross can travel over a thousand kilometres while hunting.

The animal building trade has craftsmen and 'cowboys' too. Eager to cut corners on building costs, cliff swallows renovate and re-use last year's nests, unneighbourly shags steal materials from next door, and hermit crabs aggressively play the housing market. Expertly engineered, the most desirable animal dwellings boast air-conditioning, solar heating, and defensive moats.