Once, Sir David Attenborough said he would retire from making nature documentaries when he turned 80. Well, that never happened. Attenborough turned 89 on Friday, still lending his legendary eye and voice to the incomparable programs he's made for decades. He doesn't plan to stop anytime soon.

"You'd be amazed at how much we have failed to show," the famed British TV explorer told The Washington Post last week. "The natural world is hugely varied with a vast number of species. And we will always find something new to show you."

His newest documentary, "David Attenborough's Rise of Animals: Triumph of the Vertebrates," tells the story of how vertebrates — including humans — came to be the way they are. It features some spectacular recent fossil finds that fill what Attenborough refers to as the "tantalizing gaps" of evolutionary history. It's the sort of stuff fossil nerds, Attenborough included, could spend a lifetime hoping to glimpse up close.

"David Attenborough's Rise of Animals: Triumph of the Vertebrates" will be broadcast on the Smithsonian Channel in two parts, beginning May 13 at 8 p.m.

If you're unfamiliar with Attenborough, walk right over to the nearest science lover you know and ask them. They will probably tell you, depending on age, that they wish David Attenborough was their grandfather.

The day before his birthday, Attenborough -- who was knighted 30 years ago -- sat down with The Post at the Smithsonian's National Museum of Natural History to discuss his newest project and his 60-year career as arguably the most well-respected and best-known nature documentarian alive.

This interview has been edited and condensed for length and clarity.

On his favorite fossils at the Smithsonian

It's nonstop. I suppose that really, for a European, the thing that really knocks you out here is the abundance of dinosaur stuff you have. In fact, dinosaurs were first discovered in Britain, but the really big spectacular dinosaurs were found here. It's just great to see the real things. Only too often in Europe we've put up with casts, with plaster copies. But to see the real things here is great.

Why he chose to tell the story of the vertebrates

It's one of the great stories that anybody can tell, is it not? The beginning of life, a thousand million years ago. And visible life 500 million years ago. It is one of the most extraordinary, detailed and wonderful and amazing stories you can think of. And we now understand more about it than we ever did.

It is a great story, it's a great detective story.

The new frontiers of research in Chinese fossil beds

We've only understood the motives, the drivers to this story within the last few decades. And certainly the links in this chain of developments, there've been a number that were very hard to find or missing altogether, we didn't understand how this moved to that and so on. And marvelously enough, it so happened that the missing links that were missing from European and American discoveries, the answers were found in China. For a long time it wasn't possible to go and see these things. And now it is.

The most dramatic of course, are the discoveries of dinosaurs with feathers. There was an argument in the world for decades, a really passionate — and I was going to say venomous — a very powerful argument between the experts as to what the origin of the dinosaurs were, and as to what the origin of birds more particularly were. And of course the answer is in China. To have the privilege of looking at these extraordinary fossils with feathers absolutely preserved was really thrilling.

The privilege of going to the Institute of Vertebrate Paleontology in Beijing was that they've got dozens of them. And I was saying "Oh look at that!”  and they were saying, "You wait, we'll show you this!" It was very exciting.

How to show wonder in a world with an abundance of information available about the natural world

[the reporter gives the example of a YouTube clip showing the lyrebird’s call]

I think they are so wonderful, the lyrebird. Seeing the lyrebird once is an amazement. But you don’t exhaust the pleasure of seeing a lyrebird by seeing it once. Or indeed a dozen times. You can just see it over and over again.

You'd be amazed at how much we have failed to show. The natural world is hugely varied with a vast number of species. And we will always find something new to show you

For example, I'm doing a commentary on a film that the BBC made of a little puffer fish in Japan that creates, that builds in the soft sand in the mud of a shallow bay in Japan, a huge design like a chrysanthemum but three meters — six feet, nine feet across. This tiny little thing beavers away. And you look down at the sea and you cannot believe that there's this chrysanthemum in the sand. Nobody'd ever seen it before. No scientist had seen it before. We heard about it from a Japanese diver who was wondering what on Earth it was. It's just mind-blowing.

The persistence of a debate about the theory of evolution 

BBC's David Attenborough shares his thoughts on evolution and the "overwhelming evidence" regarding climate change. (Jhaan Elker/The Washington Post)

Of course, if you're a scientist, if you believe material evidence, and you ask for material evidence to support every statement you make, that's what science is about. And you get one answer. If you think that that's irrelevant, and actually, I can just think about it and imagine it, then you get a different kind of answer.

Philosophers and religious people accept the writings and teachings and beliefs of people who have thought about the idea without seeking the material evidence for it.

On whether that debate could be reconciled 

I personally see no conflict between the idea that there might be a creator, an omnipotent creator spirit, that created this world, and chose to do it by allowing things to evolve in the way that they have. That doesn't seem to me to be blasphemous, or indeed necessarily irreligious. In fact, it has nothing to do with it. There is the evidence, and if you believe God wanted to go that way that's fine, and if you don't, that's fine. But the evidence that it went that way is irrefutable.

On why he has increasingly incorporated climate change into his natural history documentaries over the past decade

Well. I come from the BBC, and the BBC doesn't allow people unless it's made very evident — we don't grind axes. We don't propagandize. And when you're talking about a very, very important thing like that, opinion is, if it's going to be opinion, has to be seen as opinion. Usually if there's going to be an opinion there will be a contrary opinion. So you have to be very careful.

I didn't come out, as it were, on television about the reality of climate change until the evidence was absolutely overwhelming and there would be no serious scientist who would argue about the evidence.

You can argue about the interpretation of the evidence, sure. But the evidence now and has been for a decade or so incontrovertible that the climate is changing. There was an argument 10 years ago as to what degree humanity contributed to that change or drove that change. Even that has now been pretty well solved.

Which places he’s visited over the years have changed the most

I go to places where wildlife is and not where it's not. Occasionally I have made programs where we are concerned with what humanity is doing to the planet. And then I go back to places where I knew maybe 20 to 30 years ago. I was recently in Borneo, for example, making a film about the evolution of flight.

And we were traveling along the Kinabatangan River, which is one of the big tropical rivers there, and looking at it for the river it was just as wonderful as it ever was, you know, with a complex tangle of trees growing, a luxuriant tropical forest. But after that I had to travel and we traveled by helicopter.

You suddenly saw that the forest was half a mile, a mile at most, wide. And beyond it, stretching as far as the eye can see, were regimented rows of oil palm. Vast plantations of oil palm. And of course, it is a desperately sad site. But people are then unkind to say how terrible the government of Borneo is. How did they allow this?

Well the answer is that oil palm is grown in that quantity because there are a lot of hungry people in the world.

And if they don't do that, they're going to starve. So what is your choice? Well, the choice actually is to try and slow down the increase and the rate of increase in the human population.

How he chooses which violent scenes from nature — a lion hunting an antelope, for instance — to show and which to leave on the cutting room floor for his documentaries

You have a responsibility to make sure that the end of whatever passage of the film where you're showing that sort of thing, that the audience ends up with a proper appreciation of what the reality is. If you decide that we're not going to show any animals being killed or eaten or caught, you as a filmmaker or as a scientist have to realize that's fairy stories. Animals are eaten. It would be improper to pretend that they just went to sleep or disappeared. So you have that responsibility.

At the same time, it's easy enough just to go for cheap sensation and dwell all the time on teeth plunging into flesh and guts and blood and animals struggling and having their guts torn out of them. And an animal being killed, an antelope being killed by a lion is a very unpleasant sight, I can assure you. It would be very, very easy to make a sensational program about that.

You have the responsibility of putting it in the story, not distorting the facts, but not milking it for sensational purposes.

And matter of fact, of course, a high proportion, nearly all hunts are in fact unsuccessful. And so a high proportion of all hunts we show are also unsuccessful.

On whether he has a particular favorite species that has been named after him

To be absolutely truthful yes. Yes, there's one. As you know, scientific names have two components. There's a genus and there's a species. And there are quite a lot of species. And to have a species named after you, an Attenboroughi species, that's quite nice.

But to have a genus named after you is really something else.

BBC's David Attenborough shares his humbling story behind the genus named after him: the "Attenborosaurus." (Jhaan Elker/The Washington Post)

And there's a family of aquatic reptiles which was given my name which is Attenborosaurus. Attenborosaurus is really something. A specimen of Attenborosaurus is in the natural history museum in London. And so I, when they changed the label, I leant nonchalantly beside this thing with the label above. People walked by and didn't take any notice at all. So that put me in my place.