The Origin of Species: Lizards in an Evolutionary Tree

This film explores the adaptation of anole lizards (genus Anolis) to habitats common across the islands of the Caribbean. The anoles are excellent examples of adaptive radiation, convergent evolution, and speciation through reproductive isolation.

Working in the islands of the Caribbean, biologist Jonathan Losos discovered traits that enable dozens of anole species to live in different vertical niches in the forest. Differences in limb length, body shape, and toepad size reflect adaptations to life on the ground, on thin branches, or high in the canopy. Remarkably, similar combinations of these traits have evolved independently on different islands, a phenomenon known as convergent evolution. The film also describes how new species of anoles are formed due to variations in the color of their dewlaps, a reproductive trait that determines their mating behavior.

The “Abbreviated Film Guide” provides a short summary of the film, along with key concepts and connections to curriculum standards.

An audio descriptive version of the film is available via our media player.