Sea otters use tools, too. Now scientists look at their 'archaeology'
Published 31 Mar 2019, 14:16 BST

A Eurasian river otter mother relaxes with with her two seven-month-old cubs on a shoreline in Shetland, U.K.
Photograph by Charlie Hamilton James, Nat Geo Image CollectionGiant river otters like these in Ecuador are born covered with fur.
Photograph by Tim Lamán, Nat Geo Image CollectionRiver otters tend to live alone, but they socialise in playful groups.
Photograph by Charlie Hamilton James, Nat Geo Image CollectionSea otters sometimes link feet to hold each other in what's called a raft—a group of sea otters in the water.
Photograph by Roy Toft, Nat Geo Image CollectionA Eurasian river otter family plays on a shore covered in seaweed.
Photograph by Charlie Hamilton James, Nat Geo Image Collection