Herpetology

Herpetology (Greek ἑρπετόν herpeton = to creep, to ramp and λόγος logos = in this context explanation or reason) is the branch of zoology concerned with the study of reptiles and amphibians. Many biologists use the term "herp" or "herptiles" for all reptiles and amphibians.

Herpetology is concerned with poikilothermic, or "cold-blooded", groups of animals. "Herps" include salamanders, frogs, toads, an odd group of amphibians called caecilians, snakes, lizards, turtles, tuataras and crocodilians.

Two classes are categorized within herpetology, reptiles and amphibians. These groups share poikilothermy, and sometimes a superficial resemblance to one another (e.g. salamanders and lizards are often confused)but are not closely related in an evolutionary sense. Amphibians have permeable skin that allows for the exchange of gases, very much like the tissue that makes up mammalian lungs. Many amphibians do not have lungs at all, but use their skin alone for gas exchange and respiration. Amphibians have a three-chambered heart, and are often bound to water for at least some part of their lives. Amphibians have glandular skin, and many of them produce toxic secretions in some of their skin glands, warding off predators and generally tasting bad. Reptiles, by contrast, have a dry watertight skin, usually protected by scales, that normally has few if any glands. Many species of reptiles spend no part of their lives anywhere near water, and they all have lungs. The reptilian heart is a three-chambered one (four-chambered in the case of crocodilians), and living reptiles usually, if not always, lay eggs or give birth on land; even marine turtles which only come ashore for this purpose. Again, extinct creatures may have exhibited some differences. A number of reptile species, most notably some of the snake species, are born live, not hatching from externally laid eggs.

Herpetology offers benefits to humanity in the study of the role of amphibians and reptiles in global ecology, especially because amphibians are often very sensitive to environmental changes, offering a visible warning to humans that significant changes are taking place. Some toxins and venoms produced by reptiles and amphibians are useful in human medicine. Currently, some snake venom has been used to create anti-coagulants that work to treat stroke victims and heart attack cases.

People with an avid interest in herpetology and who keep different reptiles or amphibians, often refer to them selves as "herpers".