Reptiles are tetrapods and amniotes, animals whose embryos are surrounded by an amniotic membrane. Today they are represented by four surviving orders:

• Crocodilia (crocodiles, caimans and alligators): 23 species
• Rhynchocephalia (tuataras from New Zealand): 2 species
• Squamata (lizards, snakes and amphisbaenids ("worm-lizards")): approximately 7,600 species
• Testudines (turtles): approximately 300 species

Reptiles are found on every continent except for Antarctica, although their main distribution comprises the tropics and subtropics. Though all cellular metabolism produces some heat, modern species of reptiles do not generate enough to maintain a constant body temperature and are thus referred to as "cold-blooded" (ectothermic). (See the Leatherback Sea Turtle for an exception: a reptile that elevates its body temperature well above that of its surroundings.) Instead they rely on gathering and losing heat from the environment to regulate their internal temperature, e.g, by moving between sun and shade, or by preferential circulation — moving warmed blood into the body core, while pushing cool blood to the periphery. In their natural habitats, most species are adept at this, and can maintain core body temperatures within a fairly narrow range, comparable to that of mammals and birds, the two surviving groups of "warm-blooded" animals. While this lack of adequate internal heating imposes costs relative to temperature regulation through behavior, it also provides a large benefit by allowing reptiles to survive on much less food than comparably-sized mammals and birds, who burn much of their food for warmth. While warm-blooded animals move faster in general, an attacking lizard, snake or crocodile moves very quickly. A herpetologist is a zoologist who studies reptiles and amphibians.

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FWC Orders Amnesty Program For Reptiles Of Concern|The Florida Fish and Wildlife Conservation Commission (FWC) .. http://oohja.com/x3wdU
networkpetsnet (Networkpets.net) Thu, 10 Dec 2009 19:08:16 -0000
FWC Orders Amnesty Program For Reptiles Of Concern|The Florida Fish and Wildlife Conservation Commission (FWC) .. http://oohja.com/x3wdU
Vivastreet -adoption propose garde d'animaux (pas de reptiles) à la roch.. http://bit.ly/71kpfu #adoption #animal
mon_animal (mon_animal) Thu, 10 Dec 2009 19:04:30 -0000
Vivastreet -adoption propose garde d'animaux (pas de reptiles) à la roch.. http://bit.ly/71kpfu #adoption #animal
#Videocrux - A Lebanese couple sharing room with wandering reptiles http://bit.ly/4pWdid
videocrux (Videocrux) Thu, 10 Dec 2009 18:48:30 -0000
#Videocrux - A Lebanese couple sharing room with wandering reptiles http://bit.ly/4pWdid
FWC Orders Amnesty Program For Reptiles Of Concern: The Florida Fish and Wildlife Conservation Commission (FWC) dir... http://bit.ly/61tfhr
wctv (WCTV) Thu, 10 Dec 2009 18:26:26 -0000
FWC Orders Amnesty Program For Reptiles Of Concern: The Florida Fish and Wildlife Conservation Commission (FWC) dir... http://bit.ly/61tfhr
@Dreamsoftco Yeah, I am crazy about reptiles. My husband hates snakes or I'd have an awesome albino corn snake too...
JinzouTamashii (Cheryl Itou) Thu, 10 Dec 2009 17:50:28 -0000
@Dreamsoftco Yeah, I am crazy about reptiles. My husband hates snakes or I'd have an awesome albino corn snake too...
FWC orders amnesty program for reptiles of concern: [12/10/09] http://bit.ly/4yN33l #MyFWC
MyFWC (MyFWC) Thu, 10 Dec 2009 17:49:21 -0000
FWC orders amnesty program for reptiles of concern: [12/10/09] http://bit.ly/4yN33l #MyFWC

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