The Mark Test

The researchers place a white "X" on one side of Happy's head. When Happy sees the "X" in the mirror, she repeatedly touches the mark with her trunk

Wildlife

Preview thumbnail for 5 Record-Breaking Bird Migrations

5 Record-Breaking Bird Migrations (02:56)

Preview thumbnail for 10 Fun Facts About Bioluminescence

10 Fun Facts About Bioluminescence (02:38)

Preview thumbnail for How Cowboys Breed Perfect Cattle

How Cowboys Breed Perfect Cattle (04:12)

Preview thumbnail for Swimming With Sharks: Juliet Eilperin

Swimming With Sharks: Juliet Eilperin (04:16)

Preview thumbnail for Manufacturing of bitumen-lined water bottles

Manufacturing of bitumen-lined water bottles (01:41)

Preview thumbnail for A sea lion propels itself through the water at Smithsonian's National Zoo

A sea lion propels itself through the water at Smithsonian's National Zoo (00:05)

Preview thumbnail for Why Young Grassland Songbirds Sleep In

Why Young Grassland Songbirds Sleep In (02:02)

Preview thumbnail for Don't Call the Blobfish Ugly

Don't Call the Blobfish Ugly (02:21)

Preview thumbnail for 7 Weirdest Bird Calls

7 Weirdest Bird Calls (02:55)

Preview thumbnail for 10 Fascinating Facts About Owls

10 Fascinating Facts About Owls (03:04)

Preview thumbnail for 10 Fun Facts About Jellyfish

10 Fun Facts About Jellyfish (02:46)