Reptile Adaptations

There are many normal behaviors and morphological adaptations observed in reptiles that might be misinterpreted by an unfamiliar hobbyist or veterinarian as disease or trauma. For example, a monitor or Asian rat snake will often begin morning basking by raising its head from a crevice or burrow.


Reptiles are ectothermic and can adjust their body temperatures over a broad climatic range by selecting sites with ideal environmental conditions. They also employ a variety of tactics to avoid dehydration in the heat.

Body Temperature

As ectotherms, reptiles are cold-blooded and have much lower metabolic rates than endotherms like mammals. Their bodies need to rely on ambient environmental temperatures for critical processes, such as digestion and reproduction. In order to survive, reptiles must regulate their body temperature within a range of their preferred optimal thermal zone.

In the wild, reptiles have evolved a wide variety of behavioral and physiological responses to achieve their optimal body temperature through behavioural thermoregulation. This includes escaping from the sun by burrowing into the soil or hiding under a rock, increasing air flow to their skin by opening their mouths in a vasomotor response, and altering their body color to reflect sunlight (or absorb it). Many of these changes to the body are achieved through chemical reactions that increase or decrease heat transfer.

In addition, some reptiles use basking behaviour to raise their body temperature through radiant and convective heating. The lizard Sceloporus magister, for example, uses its scales and a thin layer of fat to absorb the sun’s radiant energy and elevate its internal body temperature. Alternatively, they will lie under a heat source such as a rock or log to warm up via convective heat. They also have a specialized sweat gland in their head to shed excess water to avoid overheating in humid conditions.


Reptiles evolved a variety of ways to move over land as they separated from their aquatic ancestors, resulting in the wide range of locomotor styles seen today. While most reptiles use their legs for movement, many also utilize their bodies and spine for locomotion. This helps reduce the amount of energy needed for each movement.

For instance, snakes that move using lateral undulation alternately tighten and relax muscles up and down their lengths to create horizontal waves that move down their body as they walk or swim. This method of movement also gives lizards and snakes excellent traction when climbing, as it creates force at multiple points up or down their long bodies.

A few reptiles have adapted to move in a straight line, called rectilinear movement. In this form of movement, a snake raises one foreleg and the opposite hind leg while balancing on the other two, which minimizes energy usage and prevents heat loss. It also allows a reptile to maintain its posture for longer periods of time, which may be necessary in certain habitats where the temperature is too high.

In general, all of these movement styles require a great deal of flexibility from a reptile, and this may be why most are found in unforgiving environments. For example, in a desert, the body of a reptile may have to be twisted and contorted to avoid being scorched by the sun. This flexibility in movement also explains why reptiles are difficult to study with conventional methods of habitat use, such as dBBMMs.


A reptile’s diet affects its adaptations in many ways. For example, a frugivorous animal that eats a lot of fruit may lose the ability to make its own vitamin C. This is a natural adaptation that allows the animal to consume more food from its environment, but it can also lead to the evolution of other traits that are useful in eating fruits.

The scaly skin of reptiles keeps in moisture, which helps prevent water loss from the body. This helps reptiles survive on dry land, since they cannot use their skin as a source of oxygen like amphibians can. Reptiles instead breathe with lungs, which are more efficient than the lungs of amphibians.

As reptiles evolved to live on land, they also needed to conserve water in their kidneys. This is why reptiles produce less urine and conserve the water that they do produce in more concentrated forms. Some reptiles, such as turtles and crocodiles, have scales that fuse together to form a shell, protecting them from predators and the elements.

Other reptiles have more inventive adaptations to find and kill prey. For instance, chameleons can shoot their tongues toward prey, grab it with their mouths, and then swallow it whole. They can even change the color of their eyes to better blend in with their surroundings. These are all normal adaptations that help reptiles hide from predators, escape enemies, reproduce, eat, and get around their environments.


A reptile’s environment can significantly affect its ability to survive. In fact, an animal’s unique traits are often designed specifically for the habitat where it lives. Adaptations are physical or behavioral changes that allow organisms to thrive in specific environments.

For example, a domestic yak can survive in a cold region like the Arctic Circle because it has thick fur and fat to insulate its body from frigid temperatures. However, a yak could not survive in a tropical or desert climate because it would require too much heat to stay warm and its body fat would melt in the hot sun.

In addition, many reptiles use their environments to actively regulate their internal body temperatures, preventing lethal extremes. Reptiles that live in desert regions, for example, bask in the sun during certain times of day to absorb rays of sunlight, while others may hide under rocks or crevices. Some use the environment to help move through it, too, with a ability to burrow into dirt, swim in water or sidewind across loose sand.

Even a small change in the climate of a reptile’s habitat can have an enormous impact. For instance, ectothermic reptiles such as snakes, lizards and crocodiles rely on ambient environmental temperatures to maintain critical physiological processes, so they are particularly sensitive to altered temperatures. They can also be adversely affected by rapid temperature shifts because their thin skin provides little insulation and because they lack the ability to generate heat internally.