Join Our Whatsapp and Telegram Channel to Get Free eBooks Telegram | Whatsapp

Cold-blooded vs Warm-blooded animals

What are Cold-blooded animals?

  • The animals that are cold-blooded are those who are incapable of controlling their body’s temperature in accordance with temperatures of their environment.
  • The body temperature is fluctuating as they move through different areas with different temperatures.
  • Therefore, they don’t maintain the ability to maintain a constant body temperature. Due to this, they are not able to survive in extreme temperatures.
  • The reptiles that are cold-blooded include amphibians, fishes and invertebrates. They are also known as poikilothermic animals.
  • The animals that are cold-blooded usually exhibit one or more of the three thermoregulation mechanisms: Poikilothermy, Ectothermy, or Heterothermy.
  • Poikilothermy is the condition in which the internal temperature of animals may vary, but the temperature of their core is usually exactly the same as the temperature of the surrounding environment.
  • Ectothermy is the term used to describe the method which animals employ external methods, such as the sun, in order to regulate the body’s temperature.
  • Heterothermy refers to the method in which the body temperature could change drastically when the animal is moved between different environments.
  • They have a few mechanisms that allow them to exercise a limited influence over body temperature. The majority use some combination of the above listed three mechanisms of thermoregulation.
  • As they transition between temperatures the body temperature could change drastically which is why they need to rely more on external factors such as sun and water to regulate your body temperature.
  • A few examples of this are in crocodiles, lizards, and lizards. remain in the water during the summer months and move to the land via digging pits in order to keep warm during colder seasons.
  • They are restricted within the aquatic and terrestrial ecosystems due to their dependence on environmental temperature for their metabolic processes.
  • Poikilotherms are known to have more complicated metabolisms than other species. For one chemical reaction they may have up to 10 different enzyme systems that operate at different temperatures.
  • In the end, they are more complex in their genome than warm-blooded mammals that are in an ecological space for frogs.
  • Poikilothermic species do not possess complex organ systems with high energy such as wings or brains because their metabolisms are so varied. Instead, they possess additional adaptations like fish swimming muscles that can be heated through heat exchange.

Examples of cold-blooded animals


Fish are creatures that are cold-blooded and consequently have a fluctuating body temperature when they move around in environments with various temperatures. The water resources are diverse temperatures at different levels. So, when fish change from one place to another the body temperature changes as well.

An abrupt change in environment could trigger major changes in the metabolism, fluid-electrolyte balance, as well as the acid-base relationship in fish. Therefore, they use the physiological and behavioral thermoregulation systems. To attain thermoregulation that is behavioral Fishes are known to travel around in search of waters that are at the appropriate temperatures to ensure their survival.

Certain fish species, such as tunas and lamnid sharks possess specialized anatomical features to countercurrent heat exchange, which is a method of conserving the heat within the muscles of the lateral swimming. Though the thermoregulatory systems within a fish are not able to keep the same inner body temperature, it is possible that they may help to anticipate changes in the body that naturally occur with thermal change. Fish that are found in the polar regions produce antifreeze, which reduces the freezing point of body fluid, thereby protecting from the freezing cold of water.


Crocodiles are reptiles of cold blood and have a fluctuating body temperature. Crocodiles prefer a body temperature of 30 to 33 degrees Celsius and to attain this temperature, they are able to move between the warm and cold areas of water and land.

The animals typically orient themselves so that the majority of their body is in the direction of the sun. However, as their body is getting warmer it turns to face the sun to decrease the amount of heat absorbed by their tiny head. Also, they open their mouths to cool their brain by Evaporative cooling.

In this way, they can achieve thermoregulation behavior by taking advantage of their thermal environment. Particularly designed peripheral nerves are found on the skin of the majority of reptiles and can be able to respond to different environmental conditions.

What are Warm-blooded animals?

  • Warm-blooded species are those which can keep an almost constant body temperature, regardless of temperature fluctuations in the surrounding.
  • Their body temperature stays the same even as the move from place to the next.
  • Warm-blooded animals possess a variety of internal mechanisms to help them gain warmth in colder environments and cool down in warmer regions. They achieve this by controlling their metabolic rates.
  • Warm-blooded animals are mainly birds and mammals. They are also known as homeothermic animals.
  • Animals with warm blood, as well as cold-blooded animals, have distinct mechanisms to regulate temperature; Endothermy and Homeothermy.
  • Endothermy is the term used to describe the method through which animals regulate their body temperature by internal mechanisms such as sweating, burning calories, panting and panting.
  • Homeothermy is a method used by animals to maintain an internal temperature that is constant instead of external temperatures that fluctuate.
  • The majority of warm-blooded animals utilize both of these methods to maintain the same body temperature.
  • While metabolic processes are primarily associated with managing body temperature, other structural elements are also involved in determining body temperature.
  • Certain mammals have fur that is thick during winter , and have a tinier coat in summer. In the same way, depending on the type of mammal that sweat glands are present that either are present all over all over the body (primates) as well as located (dogs).
  • Certain homeothermics might have a lack of food in the winter months in order to sustain their metabolic processes up and running. In this case, the animals are subject to a period of hypothermia, also known as hibernation.
  • Because of their capability to survive in harsh environments homeotherms are able to exploit many and diverse niches compared to poikilotherms.
  • Homeotherms also have less complicated metabolisms since they don’t need to alter their metabolic processes as the temperature fluctuates.

Examples of warm-blooded animals


Birds are warm-blooded mammals with a constant body temperatures that don’t fluctuate regardless of how the temperature of the surrounding area changes. Birds engage in various metabolic processes that result in heat production or loss, to keep the same temperature. The feathers of birds guard them from extreme temperatures or extreme heat.

Similar to this, many birds such as ducks prefer to cover feathered body areas like limbs under the feathers to avoid loss of heat. The physiological reason is that they increase the rate of metabolic activity to boost body temperature when temperatures drop. Certain birds may move into the water to shed heat via cooling by evaporation. The variety in the bird’s ecological niche is because of their ability to withstand extreme temperatures while keeping a constant internal temperature.


Mammals are warm-blooded that have the body temperature that is constant, even when the temperature of the environment changes. The body of these animals is covered in fur or hair which help maintain the temperature. Alongside these features of the structure there are a variety of physical and behavioral modifications help in maintaining increasing the temperature inside. Different mammals inhabit different ecosystems across the world , because they possess an individual mechanism for adapting to the specific environment.

The process of thermoregulation in mammals takes place through diverse mechanisms. Certain mechanisms utilize heat production, while others keep the existing heat. The thermostat in mammals also serves as an effective defense against attack by pathogens of different kinds.

Key Differences between Cold-blooded and Warm-blooded animals (Cold-blooded vs Warm-blooded animals)

Basis for ComparisonAnimals with cold bloodAnimals with warm blood
DefinitionAnimals with cold blood are those that aren’t capable of controlling the body’s temperature to their temperature surroundings.Warm-blooded animals are those which can keep the same body temperature regardless of temperature fluctuations in the surrounding.
Also calledAnimals with cold blood are also known as poikilothermic animals.Animals with warm blood are referred to as homeothermic animals.
TypesThe cold-blooded mechanism are generally categorized as:1. Ectothermy2. Poikilothermy3. HomeothermyWarm-blooded animals can be classified into broad categories, such as:1. Endothermy2. Homeothermy
Temperature of the bodyThey don’t have a specific body temperature since their body alters its temperature in accordance with the temperature in the surroundings.Usually the body temperature is constant , and can range from 35-40degC.
Rates of metabolic conversionThe metabolic rates of cold-blooded animals depend on the ambient temperature.In warm-blooded mammals, environmental changes do not have any effect on the metabolic rate.
PhaseThey go through two phases in order to guard against extreme weather. Hibernation is the time of rest during winter, which can last between weeks and months. Aestivation is a time of rest, occurs in summer.They rarely experience any of these phases because they are able to adjust to fluctuating temperature of the environment. Certain animals go through a time of cold, known as hibernation.
Organ systemPoikilotherms don’t have organ systems with high energy as brains do.Warm-blooded animals have intricate organ systems.
Regulation of heatCold-blooded animals are able to regulate the temperature of their body through activities like stretching their limbs in the sun or changing body hues while bathing in the sun, etc.Warm-blooded animals engage in a variety of ways to regulate body heat , which includes metabolic processes and adaptive ones like sweating, panting or moving, altering their body surface area, body volume ratio, etc.
Resistance to microorganismsCold-blooded animals have a resistance to microorganisms. When they contract a disease they decrease body temperature to protect themselves.Warm-blooded animals have a better immune system to protect against these microorganisms.
Energy productionThey get energy through warmth to regulate body temperature to ensure survival.They are able to produce heat in their body.
SurvivalAnimals that are cold-blooded cannot withstand extreme temperatures and conditions.Warm-blooded animals rapidly adapt to any environment, and temperatures.
Heat sourceThey are mostly dependent on direct sunlight and the heat of the environment around them.They generate heat through the consumption of food.
ProteinsCold-blooded animals contain multiple proteins, and each operates at different temperatures.The proteins in warm-blooded animals are not temperature-specific.
GenomeThe genome of some cold-blooded species could be more complicated.The genome of the majority of warm-blooded mammals has a lower level of complexity.
The effect on body fatsOverheated bodies are the result of excessive fat. the cold-blooded animal’s bodies and could lead to the end of life.Fat is vital for warm-blooded animals since it aids in keeping body temperature, particularly for animals such as seals or whales, who are found in cold oceans.
ExamplesFishes, invertebrates sharks, frogs, the crocodile, etc. are a few examples of cold-blooded animals.Animals and birds are both examples of warm-blooded mammals.
Cold-blooded vs Warm-blooded animals
Cold-blooded vs Warm-blooded animals

Related Posts

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.

A new weapon in the battle against antibiotic resistance 16 Important Skills Needed For A Successful Career in Bioinformatics Top 5 High-Paying Biotech Jobs in India (No PhD Required) Top Emerging Trends in Bioinformatics Important Skills Needed For A Successful Career in Bioinformatics Research reveals plant pathogens repurpose phage elements for bacterial warfare Scientists show the key role of spleen and extracellular vesicles in cryptic malaria infections Scientists reveal molecular link between glucose sensing and pyroptosis cell death Scientists reconstruct ancient genomes of the two most deadly malaria parasites to identify origin and spread What are TaqMan probes?
A new weapon in the battle against antibiotic resistance 16 Important Skills Needed For A Successful Career in Bioinformatics Top 5 High-Paying Biotech Jobs in India (No PhD Required) Top Emerging Trends in Bioinformatics Important Skills Needed For A Successful Career in Bioinformatics Research reveals plant pathogens repurpose phage elements for bacterial warfare Scientists show the key role of spleen and extracellular vesicles in cryptic malaria infections Scientists reveal molecular link between glucose sensing and pyroptosis cell death Scientists reconstruct ancient genomes of the two most deadly malaria parasites to identify origin and spread What are TaqMan probes?

Adblocker detected! Please consider reading this notice.

We've detected that you are using AdBlock Plus or some other adblocking software which is preventing the page from fully loading.

We don't have any banner, Flash, animation, obnoxious sound, or popup ad. We do not implement these annoying types of ads!

We need money to operate the site, and almost all of it comes from our online advertising.

Please add to your ad blocking whitelist or disable your adblocking software.