Reptile species have horny scales, paired limbs with 5 toes, highly developed lungs (as opposed to gills) for breathing, and eggs with hard protective shells (except for some snakes and lizards that give birth to live young). A few reptiles also practise asexual reproduction.크레스티드게코분양
Most reptiles are ectotherms, meaning they must self-regulate their body temperatures by basking in the sun or entering a state of torpor or brumation (similar to hibernating). Some (like the Komodo dragon) have fangs to deliver venom when threatened.
Reptiles have long captivated human interest, and their genetic blueprint is a testament to the marvels of evolution. Their scaly skin, slithery movements and survival tactics, including camouflage, mimicry, hibernation, thermal regulation and more, continue to fascinate scientists.
The Class Reptilia contains more than 6,500 species of lizards, dinosaurs, alligators, crocodiles and snakes. These creatures are the dominant land vertebrates in many ecosystems. They occupy every terrestrial habitat except Antarctica and live in nearly all climates.
Like mammals, reptiles are tetrapods, descended from four-limbed ancestors. Unlike amphibians, most reptiles are oviparous, laying eggs with protective leathery shells. But some lizards and snakes are viviparous, giving birth to live young. In viviparous reptiles, the fetus develops inside the mother, using various forms of a placenta similar to those found in mammals.
Most reptiles are cold-blooded, with thin skin that does not provide insulation and no sweat glands for regulating body temperature. Consequently, they require external sources of heat to survive, basking in the sun or seeking shelter in cool areas when needed.
The skull morphology of reptiles is also unique, with one bone where the mammalian malleus and incus are located. In addition, some reptiles have a third ear bone to help filter out low frequencies of sound and a jaw that is stronger than in other mammals.
Reptiles need a variety of habitat types to survive. Most have adapted to live in dry or moist terrestrial, freshwater or marine habitats. Their scaly skin protects them from excessive heat or cold. They lay eggs, but some, such as the Puerto Rican boa and the Kemp’s ridley sea turtle, also give birth to live young. They are ectotherms, so they need to find warm or cool spots to bask and spend time resting or moving around as temperatures change.
In arid landscapes, open habitat is important for reptiles because it provides many different ground temperature variations; and in aquatic habitats, open areas allow them to move easily between breeding, overwintering and foraging sites. Site managers can encourage reptiles to use the area by providing corridors between the needed habitat types. These may include riparian corridors along safe upland dispersal routes; or links between arid desert overwintering sites and aquatic breeding areas, or between upland nesting sites and wetlands where they can forage.
Some reptile species, such as the sand snake and a number of lizards (including amphisbaenians) have flattened tails that help them glide from high trees. Other reptiles can use their bodies to climb, or their jaws to chew rocks and other hard surfaces. They may also make use of disused industrial sites, where the rough structures provide ideal habitat conditions for hiding and sheltering.
Reptiles can be classified as herbivores (eating only plant matter), insectivores (eating insects), carnivores (eating animals) or omnivores (eating both plants and animal matter). Herbivorous reptiles, such as land turtles and water dragons, are best fed a fresh salad of greens, fruits, vegetables and small amounts of meat. Omnivorous reptiles are best fed a diet that includes both plant and animal proteins, as well as insects, invertebrates and small prey. The dietary needs of individual reptiles vary greatly, and new research constantly brings to light new information about the nutritional requirements of various reptile species.
The diet of a particular reptile species is determined by its habits in the wild and the food it would naturally consume in its natural environment. Familiarity with a reptile species’ feeding habits is essential, particularly for determining appropriate foods and nutrient levels. It is common practice to offer two or more different types of prey for feed, since significant differences exist in the nutrient levels of vertebrate and invertebrate foods. This also helps to reduce dependence on a single prey item that could become periodically difficult to obtain.
All feeders must be mindful of the fact that reptiles are opportunistic eaters and will eat what is available to them. This can result in the over consumption of certain foods, and a lack of other nutrients in the body. Over time, this can lead to obesity and other health issues for a reptile. In order to avoid this, the feeder must ensure that an enclosure is large enough to provide a number of suitable places for reptiles to eat, and to provide furnishings and open space to move around in. Separate feeding enclosures are required when two or more snakes or lizards are housed together as they may be attracted to the same food sources.
Reptiles, like all tetrapods (animals with four limbs descended from semi-aquatic amphibious ancestors), lay eggs enclosed in shells. But some, such as certain species of snake and lizard, give birth to live young (viviparous).
The length of time that elapses between a reptile’s conception and the hatching or birth of its offspring varies from one species to another. The gestation period can last a few weeks or several months. Some reptiles have specific breeding seasons, but others breed year-round.
Like mammals, many reptiles display ritualized courtship behavior before copulation occurs. A famous example is the infamous “courtship dance” performed by male garter snakes in which they hold their foreparts of their bodies together and entwine them to compete for the attention of the female. Typically, a victorious male will follow the female’s odour trail to her hiding place where she may be awaiting him.
Reptiles, including snakes, lizards and turtles, are relatively solitary animals for most of the year but often gather in social groups during breeding season. They are a vital part of the ecological system and provide valuable pest control services in temperate and tropical areas. They are also harvested for meat, skins and pet trades. Reptiles have an important economic impact in many regions, providing jobs in agricultural sectors and other natural resources industries.