Frogs have been on Earth for more than 200 million years, and range in size from half an inch (the Cuban tree toad) to the much larger goliath frog of West Africa, which can grow to 15 inches and weigh up to 7 pounds. As a public service, the American Museum of Natural History has created this thoughtful online site that introduces visitors to the world of frogs, and as a way of highlighting their own work with these amphibians, both in the field and at the Museum. After reading an introductory essay, visitors can peruse a section on a number of frog species, which include some fine photographs and general information. Visitors will want to take a look a the Budgett's frog, which can puff up its body with air, arch its back, and scream like a cat in order to frighten intruders. The rest of the site is equally delightful, including a nice area on the reproductive cycle of frogs, a live "FrogCam" direct from the Museum, and a great section containing the sounds of frogs from the island of Madagascar.