Designer dogs: What is a breed anyway?

There's designer clothes, but they have nothing on designer dogs!

They come in a huge range of shapes and colours and sizes, from the tiny Chihuahua to the Great Dane.

In the animal world this much variation usually means different species, but not for dogs — so where did they all come from?

And what role did Victorian-era rats play in the development of 'breed standards'?

Featuring:
Joyce Sullivan, papillon breeder
Wayne Douglas OAM, Afghan Hound breeder
Esther Joseph, all breeds judge
Michael Worboys emeritus professor the University of Manchester
Professor Greger Larson, evolutionary genomics at the University of Oxford
Dr Angela Perri, zooarchaeologist, Chronicle Heritage
Dr. Elaine Ostrander, geneticist at National Institutes of Health (US)
Dr Heidi Parker, geneticist at National Institutes of Health (US)

Production:
Ann Jones, Presenter / Producer
Nat Tencic, Producer
Rebecca McLaren, Producer
Petria Ladgrove, Executive Producer