WGBH

Anthropologist Niobe Thompson travels the world to uncover how the relationship between humans and horses evolved.

A chameleon searches for a mate in Madagascar; a Scottish water vole swims a lake, climbs a waterfall and scales a mountain to find a place to raise her pups.

The crucial ecological roles that beetles play in nearly every environment, and why they are often regarded "the most important species on the planet.".

The Neighborhood's garbage problem is solved through a cooperative effort.

Muffy, Francine and Molly make their own movie; D.W. wants to get married.

Martin and Chris try to rescue a foal who is separated from his mother by a rogue wave.

The Hunters search for a way to monitor the weather after they lose power during a thunderstorm.

Lyla gets a strike her first time bowling but gets frustrated when she realizes bowling isn't as easy as she thought it was; Lyla feels left out when Everett and Ale's friendship thrives.

Carl and Sheldon are on a thank-you mission; Carl shows his friends the right way to play with pet rocks.

The children put on a show at school, each doing something that makes them special; Dad reminds Daniel of the things that make him special.

Phoebe and Jay learn how to keep cool while using their thermometer to track the temperature in the apartment; Pete and Grandma Annie teach the kids how to tell time.

Rudy is afraid of getting a shot at the doctor's office, so Nina and Abby play pretend to show what the visit will be like so he can feel less scared.

Kemp Harris describes a life-changing moment at a stop sign; Justin Werfel's one-wheel ride; Jannelle Codianni confesses that magic is not always real.

Performance footage of folk group Peter, Paul and Mary.

A look at the documentary series by Ken Burns that illustrates how the American Revolution came to life.

Billy Joel's record-breaking 100th consecutive performance at Madison Square Garden; special appearances by Sting and Jerry Seinfeld.

From the bustling streets of Madrid to the rugged countryside, exploring the wonders of classic Spanish craftsmanship in food, fashion, ceramics, jewelry and more.

Grammy Award-winning mariachi singer Vicente Fernández performs a historic farewell concert at Mexico City's Estadio Azteca.

Broadcast performance clips from 1956 include Elvis Presley's appearances on "The Ed Sullivan Show" and "The Steve Allen Show.".

Cast and creators provide behind-the-scenes insights into Season 6.

Edith is enthusiastic about her wedding and hopes to convince her family that Strallan's age does not matter. With Downton's finances dire because of Robert's actions, Mary takes matters into her hands -- but the personal price may be high.

Reba McEntire performs some of her biggest hits at Madison Square Garden; songs include "Turn on the Radio," "Can't Even Get the Blues," "Going Out Like That" and "Fancy.".

The life, career and music of Dolly Parton are reflected in interviews with friends, companions and the artist herself, mixed with clips of Parton's performances.