Amphibians make up the most primitive group of vertebrates. Their name means "double life" (amphi = both and bios = life) and they are ectothermic animals, that is, they depend on external sources of heat to control their internal balance. In addition, they are amniotics, like fish. This means that your embryos are not surrounded by a membrane: the amnion.
On the other hand, the evolution of amphibians and the...
There are about 3,400 species of snakes, and less than 10 percent of them are venomous. Despite this, snakes are a symbol of fear for human beings, often personifying evil.
Snakes, or snakes, belong to the order Squamata (popularly known as scaling), along with chameleons and iguanas. These animals are characterized by having the upper jaw totally fused to the skull, and a lower jaw that is very mobile, in addition to a tend...