The long and complicated history of breeding a new kind of bird: the domesticated turkey.

The behavior of dogs is shaped in part by instinct that is selectively bred. View photos of popular dog breeds and learn about their hard-wired behaviors.

For 6,000 years, the Bedouin have bred Saluki from only the quickest dogs with the best eyesight.

The selective breeding that created the hundreds of modern dog breeds has put purebred dogs at risk for a large number of health problems, affecting both body and behavior.

Genetics and brain physiology can affect a dog's personality and behavior.

In this lesson, students will use segments from Nature: Wild Balkans to explore the roles and interrelationships of organisms in the varied environments of the Balkan Peninsula.

These video segments from Nature: Wild Balkans are designed for classroom use for students to explore the roles and interrelationships of organisms in the varied environments of the Balkan Peninsula.

Cat breeding has become a multi-billion dollar business around the world, with breeders constantly competing to create exotic new varieties that might win the blue ribbon at the next pet show.

Clips from the NATURE episode "Holy Cow!" show the cow's digestive system and illustrate other naturally evolved and artificially selected traits of cattle.