An animal with smooth, gray skin jumps from the ocean waves. Its tail waves up and down before it quickly dives again. Did you just see a dolphin? Or was it a p

"The Porpoise or Dolphin book in the Which Is Which? series helps readers discover the similarities and differences between porpoises and dolphins"--

In this updated edition, award-winning author and whale researcher Erich Hoyt takes readers into the field for an intimate encounter with 93 species of cetacean

Dolphins and porpoises look very similar, but while these mammals share some features they aren't even in the same family. From tooth and jaw shape to the way t

The eighty-nine cetacean species that swim our seas and rivers are as diverse as they are intelligent and elusive, from the hundred-foot-long, two-hundred-ton b