크레스티드게코 Reptiles differ from amphibians in that they have adapted to live on land. Their scaly skin contains water-resistant keratin and waxy lipids that reduce moisture loss.
They also have impermeable shells, a specialized skeleton and a special way of shedding their skin. Some reptiles go into brumation, a period of reduced metabolism and inactivity during cold weather.
Thermoregulation is the ability to maintain one’s body temperature in agreement with the ambient environment. It is a function of body surface area, metabolic heat production, and the rate at which impulses are fired from pit organs. It is not to be confused with thermal conformity which defines a reptile as a thermoconformer if its body temperatures closely match the environmental temperatures (see Figure I).
Because reptiles have thin skin and little internal metabolic warmth they must be able to adapt quickly to changes in their environments, particularly to fluctuations of both air and ground temperatures. Thermoregulation is essential to all reptile behaviors and is most evident in ectothermic reptiles such as snakes and lizards who, like other ectotherms, must shuttle between warm and cool areas of their habitats to maintain their preferred body temperatures.
The optimum physiological body temperatures for these ectothermic reptiles are determined by their natural habitats and how much of the sun’s rays penetrate them. Those species that are primarily heliothermic – such as the Sahara viper Cerastes – bury themselves in sand with only their heads protruding (thigmothermia) and can therefore achieve high basking temperatures despite significant variations of both the air and ground temperatures.
However, there are a series of critical body temperature zones in both the ecological maximum and minimum that set absolute limits to where and when these reptiles can 크레스티드게코 survive. These physiological thresholds, which also restrict the effectiveness of their muscular coordination, are known as ecological critical maxima and minima.
Reptiles, like all animals, share some physical and behavioral adaptations. A polar bear’s thick fur, which keeps it warm, is an example of a physical adaptation; a lizard that “plays dead” to avoid predators is a behavioral adaptation.
Most reptiles are ectotherms, meaning they rely on the environment to regulate their body temperature rather than generating heat through metabolism. This gives them some advantages, such as the ability to survive on a fraction of the calories required by endothermic animals. Reptiles also can adjust their body temperatures by moving in and out of sunlight, finding shady spots or going underground to cool down.
Because reptiles have thin skin and little insulation, movement is important. Most species are able to run and climb, and their legs have long toes for gripping surfaces. In addition, they have limbs that can fold into their bodies and a wide range of body postures.
Most reptiles are terrestrial, living on land, but a few species (such as turtles and crocodiles) spend most of their lives in water. These species have adapted to aquatic life by having a specialized shell for protection and lungs that can extract air from water. Some, such as a gecko’s ridged feet, are designed for climbing; others, like a snake, move by bending their bodies back and forth.
Reptiles use their senses of sight, touch, smell and hearing to find food. For instance, lizards can stick their tongues out and “catch” scent particles in the air, which they then place on their roof-line where sensory cells are located to help them locate prey or potential habitat.
The external covering of a reptile is usually dry, with few glands, and the skin is characterized by cycles of growth and death that create a tough, horny surface. In some species, bony plates develop in the dermis — the layer just beneath the epidermis. These plates help the reptile to grip surfaces or other animals when necessary.
Most reptiles have a skeletal structure that includes a bony skull, a long vertebral column that encloses the spinal cord, ribs that form a protective boney basket around the viscera and a framework of limbs. The limbs are used for locomotion, and many reptiles adopt a sprawled posture when at rest to conserve energy.
Many pet reptiles are herbivores, and a diet of fresh green vegetables, fruits and commercial “kibble” satisfies them. Carnivores must be fed warm-blooded animals, such as rodents and fish. When feeding a pet reptile, a knowledgeable veterinarian should be consulted to determine the animal’s specific needs and proper diet. Feeding inappropriate foods can lead to nutritional imbalances that often induce illness.
Reptile breeders produce reptiles for a wide variety of purposes, including the sale of pets. They may choose to specialize by breeding a single species of reptile, such as chameleons, snakes or turtles. A reptile breeder can operate a small, local breeding operation or produce reptiles for national commercial-scale production and marketing. They also may choose to concentrate on producing certain color variations in their species of choice.
Successful reptile breeding requires a high degree of knowledge of the particular reptile’s needs and natural environment. For example, lizards need to be kept in an environment that mimics their place of origin, such as a desert or rainforest, with proper humidity levels. Similarly, turtles need to have access to a deep water dish for swimming and a sand/gravel substrate for basking. Turtles also need to be able to hibernate during the winter and then emerge from their ponds in spring for mating.
Many reptile enthusiasts consider breeding their own reptiles to be the pinnacle of achievement in the hobby. However, it is important to realize that breeding a reptile can be quite challenging, especially for those new to the hobby. For example, introducing a male and female lizard to one another without adequate time for courtship and mate selection can result in the female being impregnated by a rival. In addition, many reptiles have a day/night cycle that plays an important role in their breeding behavior.