Inside Animal Hearts and Minds: Bears That Count, Goats That Surf, and Other True Stories of Animal Intelligence and Emotion

As Charles Darwin suggested more than a century ago, the differences between animals and humans are “of degree and not of kind.” Not long ago, ethologists denied that animals had emotions or true intelligence. Now, we know that rats laugh when tickled, magpies mourn as they cover the departed with greenery, female whales travel thousands of miles for annual reunions with their gal pals, seals navigate by the stars, bears hum when happy, and crows slide down snowy rooftops for fun.

In engagin...