All are web-based and maintained by an all volunteer staff. Focus on Vertebrates Vertebrate View's educational and activist efforts focus on benefiting vertebrates, with a primary, but not exclusive emphasis on non-human vertebrates. These latter characteristics guarantee that vertebrates in particular have the capacity to feel pain and suffer .
All vertebrates have, either as an embryo or an adult, gill slits or pouches.
Vertebrates never have more than two pairs of limbs. Chondrichthyes -includes sharks and rays, which have skeletons made of cartilage instead of bone. Osteichthyes -includes more advanced fish, such as salmon, trout, perch, which have bony skeletons. Amphibia -includes frogs and toads, which live both in water and on land. Reptila -includes turtles, lizards, snakes and crocodiles.