An enchanting study by a Swedish zoologist of the sleek little rodent whose complicated carpentry has caused so much delight and puzzlement. Mr. Wilsson has happily extricated himself from the log jam of scholarly impedimenta, and collects his experiments, observations, and background knowledge with energy and humor -- and in no particular sequence. Seems that except for social conduct most beaver behavior is inborn. The Wilsson beavers, in captivity, merrily rustled about carrying building material with no viable project in mind. One female, freed from her terrarium at the school where her observer was teaching, defiantly laid her scent up and down the halls, preparatory to leveling the walls. The dam-building instinct has been investigated and Mr. Wilsson discovered that by playing a recording of running water, his captive male, raised from a pup of four days, hove to, and began building in his tub. The author is enchanted with his beavers--as they stand on their hind legs and box each other; as they groom themselves. Such was Mr. W's devotion that he ""groomed"" an orphan beaver to start the grooming instinct with painful results. Informal, charming, informative--and we'll never wear beaver again.