It has a flow to it, with ideas building on each other, and every new animal and plant fitting into the greater theme. Which is this: “Islands are where animals and plants become transformed into new species with extraordinary speed,” says Attenborough. He shows how island birds often become flightless, and island reptiles often become giants. He shows how, on Hawaii, honeycreeper birds and Drosophila flies have adapted to new niches and so radiated into a multitude of new species. That, after all, is why islands are so interesting—why they’re worthy of an hour of your viewing time. They are where evolution goes to town, producing life at its most atypical. It’s no coincidence that both Darwin and Wallace came up with the idea of evolution by natural selection after lengthy voyages to islands.

Such themes are front and center in The Living Planet, but just casually hinted at in Planet Earth II. In the former, islands are the point of the episode. In the latter, they’re more of a backdrop. Where The Living Planet offers a cohesive essay about life on islands, but Planet Earth II dishes up an anthology of short stories that happen to take place on islands.

It would be too knee-jerk to ascribe this change to the death of intellectual TV, where education has been sacrificed at the altar of spectacle. I think it’s more that nature documentaries have been limited by the same technology that makes them so compelling. When you can get beautiful, high-definition, slow-motion, ground-level shots of an animal, it’s not enough to just show it and start talking. You need build-up. You need to swoop in on the island of, follow a tail as it drags across a beach, catch a scaly body in the reflection of a tidal pool, and reveal a powerful clawed foot as it thumps into the sand—and only then can you show the entire Komodo dragon. The storytelling language of wildlife documentaries has become more cinematic, and every vignette becomes longer. That necessarily reduces the amount of material you can get through in a given hour.

Another factor must surely be the degree of Attenborough’s involvement. It’s a common misconception that shows like Planet Earth and Planet Earth II are “Attenborough shows”; in truth, he merely narrates and appears in the odd introductory scene. When he actually writes and presents a series, the results tend to be more didactic but no less fantastic—even now. His latest show Light on Earth, a little-known one-off program about luminescent animals, is vintage Attenborough—spectacular, densely informative, and released just this year.

Perhaps none of this matters. People don’t care about the natural world because of the facts they can recite about it, but because of what they feel for it. And in stoking emotions, Planet Earth II amply succeeds.

Late in the episode, we see a horde of 50 million Christmas Island crabs marching to the sea to reproduce. But some don’t make it. They are beset by yellow crazy ants, which spray formic acid into their eyes and mouths, disorienting, blinding, and ultimately killing them. “Humans brought these ant invaders here and now humans are having to control them,” Attenborough says. “Of all the species that have become extinct in recent years, around 80 percent have been islanders.” That statement, laid over a shot of ants crawling over a crab’s dead face, will arguably do more to reveal the plight of the world’s fauna than a thousand articles and lectures.

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