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Dogs and More Dogs

Program Overview


Dog NOVA presents the story of dogs and how they evolved into the most diverse mammals on the planet.

The program:

  • discusses the evolution and remarkable diversity of dogs.

  • notes that there are currently more than 400 different breeds of dogs worldwide.

  • relates two competing theories about how dogs were domesticated: Stone Age humans adopted and selectively bred wolves for tameness; wolves essentially "chose" domestication when they began to forage for food near prehistoric dumps. There, tameness was an advantage.

  • considers why dogs have tails that stick up, droopy ears, and other traits that are not found in the wolf gene pool.

  • recounts an experiment in which foxes bred for tameness produced dog-like traits, leading to speculation that the new traits were due to different levels of hormones created as a byproduct of tameness.

  • explores how dominance hierarchies in wolf society have contributed to making dogs well suited to be pets.

  • suggests that dogs specialized in specific behaviors—hunting, tracking, pointing, retrieving—and that over thousands of years humans used food to reward the dogs best at these behaviors. These better-fed dogs then had an improved chance at surviving and passing on their genes.

  • proposes a theory that the diversity found in dogs is due to subtle changes in the regulatory DNA that instructs when a gene turns on and off.

  • suggests that dogs' remarkable ability to adapt to different environments is due to an extended critical period of social development.

  • reviews the problem of genetic diseases due to extensive inbreeding.

Taping Rights: Can be used up to one year after the program is taped off the air.

Teacher's Guide
Dogs and More Dogs

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