Why do some dogs have short coats, others wrinkly faces, and still others long tails? Learn about the traits we most prize in dogs, and what they were bred for.

Written, Produced, and Narrated by Anna Rothschild Production Help from Mark Zastrow

©WGBH Educational Foundation 2014

MEDIA CREDITS

Music: "Monkeys Spinning Monkeys" Kevin MacLeod (incompetech.com) (CC BY 3.0)

St. Bernard puppy Wikimedia Commons/dbking (CC By 2.0)

We Will Fight Them On The Beaches... Flickr/me'nthedogs (CC BY-NC 2.0)

335/365-A New Camera Flickr/ShutterRunner (CC BY-NC 2.0)

A Bull and a Bulldog Are About to Attack Each Other Wellcome Images/Francis Barlow (CC BY 4.0)

A Shaggy Dog Story! Flickr/foxypar4 (CC BY 2.0)

Babygirl, English Bulldog Puppy Flickr/Amber Rosenbaugh (CC BY-NC 2.0)

Barron Flickr/I_am_Allan (CC BY-NC 2.0)

Barry Wikimedia Commons (Public Domain)

Cheguel! Flickr/Ana_Cotta (CC BY 2.0)

Black Labrador Retrievers portrait Wikimedia Comons/mrpattersonsir (CC BY 2.0)

Cara de quen caui do caminhão... Wikimedia Comons/Anderson Nascimento (CC BY 2.0)

CH_Renaissance_Hopeful_Impulse Wikimedia Commons/Belinda Hankins Miller (CC BY 2.0)

Clyde The Bulldog Wikimedia Commons/Asmadeus (Public Domain)

CockerSpanielPup Wikimedia Comons/LeCardinal (CC BY 3.0)

Dog Sled Rides (6836608704) Wikimedia Commons/Denali National Park and Preserve (CC BY 3.0)

Great St Bernard Pass Wikimedia Commons/Soumai Baba (CC BY 2.0)

Guide dog golden retriever Wikimedia Commons/Hurricane Omega (Public Domain)

Komondor delvin Wikimedia Commons/Nikki68 (CC BY2.5)

Meyerhime.sideshow.1891 Wikimedia Commons/Paul Meyerheim (Public Domain)

Miniature Schnauzer Toy Wikimedia Commons/SheltieBoy (CC BY 2.0)

Rottweiler-Head Wikimedia Commons/Rains27 (Public Domain)

Samuel Henry Alken -- Bull Baiting Wikimedia Commons/Samuel Hentry Alken (Public Domain)

Schnoodle2 Wikimedia Commons/Vontafeijos

Siberian Husky bi-eyed Flickr Wikimedia Commons/re-ality (CC BY 2.0)

Silver Miniature Poodle stacked Wikimedia Commons/Belinda (CC BY 2.0)

Smooth Miniature Dachshund puppy Flickr/Lachlan Hardy (CC BY 2.0)

File: Weenix A dog over a dead boar Wikimedia Commons/Jan Weenix (Public Domain)

The Dog Barber Wellcome Images/Henry William Bunbury (CC BY 4.0)

Brantini Show Pictures ©Marilyn Santell

Early to Rise, Early to Bed Flickr/Randy Son Of Robert (CC BY 2.0)

Ella the Snow Dog Flickr/jpctalbot (CC BY 2.0)

Do the poodle retrieving a duck Wikimedia Commons/Sally Eller (Public Domain)

Deiker Jagdbare Tiere 1093210 Wikimedia Commons/Carl Friedrich Deiker (Public Domain)

Parti-colour Longhaired Dachshund Wikimedia Commons/Raven Underwood (CC BY 2.0)

Explore! Flickr/Lacklan Hardy (CC BY 2.0)

goofus, jr. Flickr, greg westfall. (CC BY 2.0)

Standing Proud ©The Komondor Club of Great Britain

Oscar With His Friends ©The Komondor Club of Great Britain

Nelson, Skateboarding Dog Flickr/CarbonNYC (CC BY 2.0)

No Strings Flickr/Emery_Way (CC BY 2.0)

Snoozing 2 Flickr/one.juniper (CC BY-NC 2.0)

1 Papillon Wikimedia Commons/2010 PA Kennel Assoc. Dog Show (CC BY 2.0)

Pomeranians Wikimedia Commons/MissTessmacher (CC BY-NC 2.0)

Retrieving Golden Retriever in Water Flickr/rkleine (CC BY-NC 2.0)

Saint Bernard in Field ©Mary Bloom

St. Bernrd Puppy Six Weeks Old Flickr/ATIS547 (CC By-NC-SA 2.0)

St Bernhard dog (bw) Wikimedia Commons/Michael Huwiler (Public Domain)

St. Bernard -- To The Rescue by John Emms (artist) Wikimedia Commons/John Emms (Public Domain)

Truth Was All Around Me Flickr/Thomas Hawk (CC BY-NC 2.0)

Wondering Flickr/snailsareslimy (CC BY 2.0)