The amniotic egg allows reptiles, birds and mammals to lay eggs on land without drying out. The fluid-filled cavity containing the embryo is separated from the external environment by an amniotic sac that is impermeable ... More »

Vertebrate groups with amniotic eggs include reptiles, birds and mammals that lay eggs. In addition, the placenta of placental mammals is a modified version of the membranes within amniotic eggs. Animals in these groups ... More »

Vertebrate groups with amniotic eggs include reptiles, birds and mammals that lay eggs. In addition, the placenta of placental mammals is a modified version of the membranes within amniotic eggs. Animals in these groups ... More »

A crocodile eats a diet that consists of meat from fish, birds, reptiles, mammals and invertebrates. These large reptiles can eat up to half their body weight in a single feeding. More »

Animals that eat both plants and other animals, called omnivores, occur in every major animal lineage, including insects, fish, reptiles, mammals and birds. By contrast, some lineages, such as spiders, are completely dev... More »

Alaska is home to more than 1,100 known vertebrates, which includes a variety of birds, reptiles, amphibians, fish and mammals. Some Alaskan birds are the mallard duck, spruce grouse, northern three-toed woodpecker, Stel... More »

www.reference.com Geography United States Alaska

In higher vertebrates, such as reptiles, birds and mammals, there are 12 pairs of cranial nerves. Lower vertebrates, such as fish and amphibians, have 10 pairs of cranial nerves. More »