People are increasingly interested in seeing animals in natural settings, so traditional jail-like zoos are giving way to open-plan zoos, and to eco-tourism.

Barbary macaques are among the most popular tourist attractions in Gibraltar. The apes have a taste for junk food, which enables tourists to see them up close and allows scientists to easily capture them for research.

We leave the macaques in Gibraltar to travel to the Galapagos Islands to learn about marine and land iguanas.

The segment focuses on the alien striped iguanas of the Galapagos Islands, albinism in a variety of animals, and the peppered moth.

The last segment focuses on Australia. We visit the Warrawong Earth Sanctuary, where there are breeding programs to reintroduce such indigenous animals as bandicoots and quolls, creatures that came close to extinction.