Birds were flying from continent to continent long before we were. They reached the coldest place on Earth, Antarctica, long before we did. They can … - David Attenborough

Make a list of all the environmental and social problems that today afflict us and our poor battered planet. – not just the extinction of species and animals and plants, that fifty years ago was the first signs of impending global disaster, but traffic congestion, oil prices, pressure on the health service, the growth of mega-cities, migration patterns, immigration policies, unemployment, the loss of arable land, desertification, famine, increasingly violent weather, the acidification of the oceans, the collapse of fish stocks, rising sea temperatures, the loss of rain forest. The list goes on and on. But they all share an underlying cause. Every one of these global problems, environmental as well as social becomes more difficult – and ultimately impossible - to solve with ever more people.

Just as the human population was starting its unprecedented growth spurt in the late eighteenth century, this was published. It's a first edition of an essay on population by the English clergyman Thomas Malthus. Malthus made a very simple observation about the relationship between humans and resources and used it to look into the future. He pointed out that "the power of population is indefinitely greater than the power of the earth to produce subsistence for man. "Food production can't increase as rapidly as human reproduction. Demand will eventually outstrip supply. Malthus goes on to say, if we don't control human reproduction voluntarily, life could end in misery, which earned him a reputation as a bit of a pessimist. But Malthus' principle remains true. The productive capacity or the Earth has physical limits and those limits will ultimately determine how many human beings it can support. m10s58-m12s18

I don't know [why we're here]. People sometimes say to me, "Why don't you admit that the hummingbird, the butterfly, and the Bird-of-Paradise are proof of the wonderful things produced by Creation?" And I always say, "Well, when you say that, you've also got to think of a little boy sitting on a riverbank, like here, in West Africa, that's got a little worm, a living organism, that's in its eye and boring through its eyeballs and is slowly turning it blind. The creator God that you believe in, presumably, also made that little worm." Now I personally find that difficult to accommodate and so therefore [sic] when I make these films, I prefer to show what I know to be the facts, what I know to be true, and then people can deduce what they will from that.