Reptiles have inhabited the earth for millions of years. They mainly include animals like snakes, lizards, tortoises, etc.
Reptiles are creatures found in all continents across the globe except Antarctica. The Arctic region also has very few reptiles. This is primarily due to the extremely cold climatic conditions in these regions.
Most reptiles prefer warm tropical climates. They are cold-blooded creatures- that is they don’t produce much body heat on their own and rely on the temperature of the environment to survive. They can gain and lose heat as per the needs of the body, this procedure is also called thermoregulation.
- Thermoregulation is the process through which animals maintain their body temperature.
- While most mammals and birds are endothermic, that is they give away heat to the environment, Reptiles are ectothermic, that is they absorb heat from the environment.
- This happens when the metabolism of the body doesn’t produce enough heat naturally, as in the case of reptiles.
- Usually, reptiles thermo-regulate their body temperatures from the heat of the sun and may retreat to a shade when enough heat has been absorbed.
Process of Thermoregulation
Thermoregulation in reptiles happens in a manner quite like the transfer of heat in non-living objects. The processes involve the three basic steps of heat transfer – conduction, convection, and radiation.
Conduction is the process where the heat is directly transferred from one area to another when there is a difference in temperature between both.
- Reptiles use this technique to gain heat from surfaces they come in contact with. Usually, they use this method to gain belly heat.
- When a reptile lies down on a hot surface, its body is much colder than the surface, hence heat is transferred from the surface to the body through conduction.
- This process has one restriction, the reptile needs to come in contact with an area that has a higher temperature to have conduction.
Convection is the process when liquids show upward movement due to a temperature difference.
- Reptiles use this method to absorb heat from the environment.
- When the air gets heated, it tends to rise. The hot air tends to stay in the upper part while lower surfaces have much less heat.
- Reptiles tend to adjust their position as per the needs of the body.
Radiation is the process of emission of heat from surfaces having high temperatures. For example, one will feel hot near a fire or when the sun shines too brightly. This is the most common method used by reptiles to absorb heat. Sun is the best source of radiation for these animals.
Production of heat in reptiles
- Though reptiles are dependent on the environment to maintain their body temperature, it is a myth that they cannot produce body heat at all.
- They do produce a little amount of heat due to metabolism, but this heat is negligible.
- It is too little to maintain the body temperature.
- Some reptiles tend to generate body heat by shivering on purpose. This is also called shivering thermogenesis. This behavior is common in snakes, they shiver to keep their eggs warm.
Effect of thermoregulation
The most important effect of thermoregulation is that the behavior and movement of the reptiles are dictated by thermoregulation.
- For example, many reptiles in tropical regions are inactive during the day and most active during the night, but they are not nocturnal creatures.
- They act according to the temperature that suits them.
- They are usually inactive during the day because they tend to absorb heat as much as possible while the sun shines.
- This behavior is evident when some species of reptiles undergoes hibernation. Hibernation is the process where an animal sleeps throughout the winter season and is active during the summer seasons.
- Thermoregulation also affects the speed of the reptiles, for example, a colder reptile will move much slower than a reptile, which has already absorbed heat.
Advantages of thermoregulation
- An average animal spends about 90% of its energy on finding food and eating it. Most animals rely on metabolism to maintain body temperature, which requires a lot of energy. In the case of reptiles, they don’t produce much heat due to metabolism, and most of the energy is consumed for growth.
- Since reptiles can absorb and release heat from the environment, they can survive in any condition, if they get some heat to maintain the body temperature. This is one of the reasons why reptiles can be seen almost in all places around the world. They can regulate their body temperature depending on the climate, therefore adapting to all climatic conditions, provided there is enough heat for them to absorb and lose accordingly.
Losing the heat
It is as important for the reptile to lose heat, as it is to gain heat. The body loses heat, also through the process of thermoregulation.
- Usually, reptiles gain heat very quickly and need to lose the excess heat since body temperature gets too high, which can be dangerous for the animal.
- Each species has a range of temperature, which is optimum for them. If the temperature rises or falls below this range, it can prove fatal for the animal.
- It is lethal for the animal and may even cause death.
- While some reptiles can endure small fluctuations in temperature, most reptiles can’t survive this and tend to die.
- However, the fluctuations in temperature are very unlikely to happen in the natural habitats, it happens when they are exposed to unnatural climatic conditions, they are not used to.
Reptiles are generally wild animals and adjust their body temperatures as per their environment. However, some are domesticated, and, in that case, it is very important to provide the optimum temperature for the reptiles to survive and grow as per their needs.
Most reptiles like a snake can adapt to any temperature and hence do not need any special care. However, it is important to keep in mind they should be exposed to heat, to maintain their body temperature.