Did you know that tigers leave their droppings in piles called scrapes to mark their territory? Or that storks poop on their legs to cool off? Or that squid-eating penguins have pink poop? Elephants have the biggest poop in the zoo, but what animal has the smallest? "Who Pooped in the Zoo? San Diego Zoo," for children ages 8 to 12, explores animal poop as a way of understanding the behavior of animals that live at the zoo. After a general explanation of the facts and functions of feces, the book discusses how animals use poop to define territoy, establish status, find mates, build houses, and keep in touch with the rest of the herd.