The blooded species and endotherms are differentiated or not to have the ability to regulate its temperature regardless of ambient temperature.
- Ectothermic animals . Also called “cold-blooded” are those whose body temperature varies with ambient temperature. For example: crocodile, ants, cricket.
- Endothermic animals . Also called “warm-blooded” are animals that can regulate their temperature regardless of the ambient temperature. For example: dog, canary, human being.
It can serve you:
- Hibernating animals
- Crawling animals
- Poikilothermic animals
Methods to stabilize body temperature:
- Heliothermia . It is the capture of heat offered by solar radiation. It is a common method in reptiles and also used even by endoderm animals.
- Tigmothermia . It is the capture of heat by contact with hot surfaces, that is, by conduction. The hot surfaces can be stones heated for example by the sun. But the contact can also be with liquids . This is the method of many aquatic animals , as they seek warm waters.
Most of the ectotherms are insects and reptiles .
“Cold blood . ” They are called cold-blooded animals because they feel cold when touched. However, some ectothermic animals in warm environments (for example, iguanas in the desert ) can have temperatures much higher than the human body.
- It can survive more easily in times of food shortage because by not needing to maintain its stable temperature, it uses less energy.
- It depends on external weather conditions.
- It must have multiple chemical systems to adapt to different temperatures.
Examples of ectothermic animals
- Crocodile . Use the heliothermal during the day. At dusk it enters the water, which maintains the heat of the day for longer (thigmothermia). As soon as the sun rises, it remains motionless in a clear area of land, to receive its heat.
- Ants . They usually build the shallow tunnels of the anthills under stones that receive the heat of the sun. As stones keep heat longer, they transmit it to the anthill at night (thymothermia) more efficiently than earth.
- Crickets . Cricket metabolism increases with ambient temperature. Among the functions of your body that depend on your metabolism is the sound they make. Therefore, the higher the ambient temperature, the lower the pause between one sound and another.
- Desert Iguana (Dipsosaurus dorsalis). Dark-colored individuals absorb 73% of visible light and therefore of the sun’s heat. Light-colored individuals absorb only 58% of visible light. One of its methods of stabilizing body temperature is the regulation of peripheral blood flow: the vessels contract and therefore decrease the heat exchange, or they dilate (increase in size) so that the heat exchange increases. .
- Desert lizards . They take advantage of the changes in solar radiation during the day to maintain relative constancy in their body temperature. They emerge from burrows and drink alone in the early morning, squashing the body (like crocodiles) to absorb as much heat as possible. When environmental heat increases, they separate from the ground to avoid radiating heat and also decrease the surface of the body that receives heat from the sun. In this way, they manage to maintain a body temperature between 36 and 39 degrees, while the ambient temperature has variations between 29 and 44 degrees.
They have the ability to control body temperature by certain internal activities such as burning fat , panting, increasing or decreasing blood flow, or shivering.
The vast majority (but not all) also meet two characteristics:
- Homeothermy . The internal temperature remains stable regardless of the external temperature. The internal temperature is usually higher than the external one.
- Tachymetabolism . The resting metabolic rate is lower than the active metabolic rate, but not significantly. Therefore, tachymetabolic animals cannot cope with food shortages by slowing down their metabolism.
Most endotherms are mammals and birds .
- It can maintain the most appropriate temperature for chemical reactions in the body.
- Thermoregulation is maintained even in periods of inactivity, maintaining a high metabolism and energy expenditure.
- In times of food shortage you cannot slow down your metabolism.
Examples of endothermic animals
- Dog . When their body temperature increases, dogs have different mechanisms to regulate it. Although they do not have a large number of sweat glands, they do perspire from the pads of their feet. In addition, the most important thermoregulatory mechanism in dogs is panting: warm blood is pumped to the tongue where heat is removed as moisture.
- Polar bear . The body temperature of polar bears is constant and approximately 37 degrees, that is, very close to human. However, they are capable of living in much lower environmental temperatures, sometimes less than 30 degrees below zero. This is because they keep the internal temperature isolated from the external temperature thanks to thick layers of hair, skin and fat.
- Gallinas . They maintain a relatively constant temperature between 40 and 42 degrees. Although they are endothermic, young hens are more dependent on the ambient temperature to be able to maintain this temperature, so they must be protected if the ambient temperature is below twelve degrees or above 24 degrees. As with other birds, thanks to the fact that the hen maintains its own body temperature, it can in turn pass it on to its eggs when it is brooding.
- Canaries . Unlike mammals, birds do not have sweat glands, that is, they do not have sweat as a resource to lower body temperature. But they do have other resources:
- Radiation . Heat escapes through the surface of the skin.
- Driving . The heat passes to other objects (which are at a lower temperature)
- Convection . The heat radiates into the air surrounding the canary. If you are in a ventilated environment, this air rises easily, being replaced by cooler air.
- Human being . We can observe from our own experience to what extent endothermy is possible. If it is hot or cold, our body temperature always remains between 36 and 37 degrees. When it is too cold, we shiver like other animals and we can see that the tips of the fingers turn blue (in extreme cold), because the body’s response is to decrease blood circulation in peripheral areas. When it’s too hot, we sweat. In addition to being endothermic, we are homeothermic, that means that our body is prepared to always function at a constant temperature, unlike ectotherms. Therefore, if we stay in the cold for too long, we suffer hypothermia, because our body cannot adapt. Fortunately, unlike all other animals, human beings have the ability to complement our natural defenses with other artificial defenses, such as shelter and shelter.