Natural Selection in Isolation (02:35)

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In this episode of “Round Planet,” Armstrong Wedgewood (Matt Lucas) turns his attention to islands that dot the planet. Evolution runs riot when life is isolated from the wider world. Weird and wonderful lifeforms evolve to become uniquely evolved to their surroundings.

Ring of Fire (04:15)

Tectonic forces are on the move below the surface of the Pacific Ocean. This is one of the most geologically active regions of the world. It contains Hawaii, the Galapagos, and other island chains. Seeds drift for thousands of miles before taking root on newly formed islands.

Island Arachnid (02:19)

Organisms on islands are forced to adapt and change to fit their surroundings, resulting in unique invertebrate life. The small-eyed big-eyed spider relies on sensitive hairs on its body to find its way around and to catch prey.

Oviparity (02:27)

An iguana drifts across the ocean on a raft of debris. There are no male mourning geckos on a young island, but the females are still able to lay eggs. A single female could populate the island with clones of herself.

Courtship Displays (04:48)

Natural selection has produced avian mutations in the Galapagos Islands. The male blue-footed booby uses his brightly colored feet and mating dance to attract females. Frigatebirds attract the opposite sex with their neck pouches. The Galapagos penguin lives farther north than any other species.

Life on a Volcano (04:51)

Island iguanas eat prickly pears; the cacti are so full of water that they barely need to drink. Female iguanas speed up incubation time by laying their eggs on volcanic ash. Marine iguanas forage for algae in the sea. Sally Lightfoot crabs keep them free of parasites.

Bull Fight (05:18)

Sea lions spend their days lounging in the sun and cooling off in the sea. Each group consists of a dominant male and a harem of females. The giant tortoise climbs the volcano in search of food and a mate.

Credits: Round Planet: Islands (00:33)

Credits: Round Planet: Islands