As of 2015,,,, and offer alphabetical lists of animals. These sites do not require users to log in to access information. Some of the sites o... More » Science Biology Zoology

A list of endangered species is available at This list makes note of both critically endangered and endangered species. As of 2015, critically endangered species include the Amur leopard, black rhino, ... More »

Animals with exoskeletons include all arthropods such as insects, crustaceans and spiders as well as many other invertebrate animals such as shelled mollusks. Shelled mollusks include snails, tusk shells, clams, nautilus... More »

No animals actually have two distinct brains, but it was once a common misconception that the stegosaurus had two brains. This misguided idea was first theorized by the famous 19th century paleontologist Othniel C. Marsh... More »

Several species of animals are color blind or see muted colors, including dogs, cats, bulls and sharks. Many fish can see muted colors. More »

Some animals that weigh at least a ton include all species of the rhinoceros, the African and Asian elephant, the Asian gaur, and the hippopotamus. Other animals that weigh at least a ton are some species of whale includ... More »

"Warm-blooded" is used to describe animals that generate their own heat. Warm-blooded creatures are often called ectotherms. Mammals and birds are warm-blooded; reptiles and amphibians are cold-blooded. More »