David Attenborough

Reptiles and amphibians are sometimes thought of as primitive, dull and dimwitted. In fact, of course, they can be lethally fast, spectacularly beautiful, surprisingly affectionate and very sophisticated.

The Roman public's thirst for blood and pleasure in witnessing pain seems to have been unquenchable and without limit." "The caged animals were kept in dungeons below the main arena. The terrified animals in their cages were hoisted up from this pit. And not only animals, human beings too, criminals, slaves and prisoners of war. And here in this arena they were set one upon the other to provide the crowd with spectacles of the most appalling carnage. It still continues to this day in Spain.

Ever since we arrived on this planet as a species, we've cut them down, dug them up, burnt them and poisoned them. Today we're doing so on a greater scale than ever […] We destroy plants at our peril. Neither we nor any other animal can survive without them. The time has now come for us to cherish our green inheritance, not to pillage it – for without it, we will surely perish.

I don’t like rats but there’s not much else I don’t like.

Trade is a proper and decent relationship, with dignity and respect on both sides.

Our planet, the Earth, is, as far as we know, unique in the universe. It contains life. Even in its most barren stretches, there are animals. Around the equator, where those two essentials for life, sunshine and moisture, are most abundant, great forests grow. And here plants and animals proliferate in such numbers that we still have not even named all the different species. Here, animals and plants, insects and birds, mammals and man live together in intimate and complex communities, each dependent on one another. Two thirds of the surface of this unique planet are covered by water, and it was here indeed that life began. From the oceans, it has spread even to the summits of the highest mountains as animals and plants have responded to the changing face of the Earth.

This is the last programme in this natural history, and it's very different from all the others because it's been devoted to just one animal: ourselves. And that may have been a very misleading thing to have done. It may have given the impression that somehow man was the ultimate triumph of evolution, that all those thousands of millions of years of development had no purpose other than to put man on Earth. There is no scientific evidence whatsoever for such a belief. No reason to suppose that man's stay on Earth should be any longer than that of the dinosaurs. He may have learned how to control his environment, how to pass on information from one generation to another, but the very forces of evolution that brought him into existence here on these African plains are still at work elsewhere in the world, and if man were to disappear, for whatever reason, there is doubtless somewhere some small, unobtrusive creature that would seize the opportunity and, with a spurt of evolution, take man's place. But although denying a special place in the world may be becomingly modest, the fact remains that man has an unprecedented control over the world and everything in it. And so, whether he likes it or not, what happens next is very largely up to him.

If we and the rest of the backboned animals were to disappear overnight, the rest of the world would get on pretty well. But if they were to disappear, the land's ecosystems would collapse. The soil would lose its fertility. Many of the plants would no longer be pollinated. Lots of animals, amphibians, reptiles, birds, mammals would have nothing to eat. And our fields and pastures would be covered with dung and carrion. These small creatures are within a few inches of our feet, wherever we go on land – but often, they're disregarded. We would do very well to remember them.

The question is, are we happy to suppose that our grandchildren may never be able to see an elephant except in a picture book?

Midwinter, and the countryside is so still, it seems almost lifeless. But these trees and bushes and grasses around me are living organisms just like animals. And they have to face very much the same sort of problems as animals face throughout their lives if they're to survive. They have to fight one another, they have to compete for mates, they have to invade new territories. But the reason that we're seldom aware of these dramas is that plants of course live on a different time-scale.

An eye from another world; a smell-detector, investigating the path ahead. We don't often see a snail that way, and that's because we've only recently had the tiny lenses and electronic cameras that we need to explore this miniature world. But when we meet its inhabitants face to face, we suddenly realise that their behaviour can be just as meaningful to us as the behaviour of many animals more our own size.

If you watch animals objectively for any length of time, you're driven to the conclusion that their main aim in life is to pass on their genes to the next generation. Most do so directly, by breeding. In the few examples that don't do so by design, they do it indirectly, by helping a relative with whom they share a great number of their genes. And in as much as the legacy that human beings pass on to the next generation is not only genetic but to a unique degree cultural, we do the same. So animals and ourselves, to continue the line, will endure all kinds of hardship, overcome all kinds of difficulties, and eventually the next generation appears. This albatross is over 30 years old, she's already a grandmother, and this year once again she has produced a chick. She will devote the next 10 months of her life looking after it. She has faced the trials of life and triumphed, for her little 2 day old chick the trials are just beginning.