Reptiles and mammals are two vertebrates among five classes, and they include in most complicated creatures on Earth. There are around 8,240 types of reptiles, including lizards, turtles, and snakes, which make it a more differing group as compare to mammals that are about 5,400 species. Mammals, which incorporate bears, whales, and primates, are accepted to have advanced from reptiles 240 million years back. Mammals and reptiles have possessed the Earth for a considerable number of years now. Reptiles and mammals are both oxygen-breathing vertebrates that need food for a living. Both have the parts of the same organ, for example, the mind, heart, lungs, and stomach. Both usually have four limbs. In this article, we will explain the differences between these two vertebrates.

Reptiles

There are four primary groups of reptiles that include lizards and snakes; turtles and tortoises, crocodiles and alligators, and the tuatara. Numerous reptiles spend their energy on land, yet some spend a lot of time in the water. Reptile species can be seen in a wide range of living spaces except for polar ice and tundra. All reptiles are vertebrates, ectothermic, and cold-blooded animals. They can’t control their body heat, so they rely on sunlight. Their body is covered with scales, and they have lungs but no diaphragm for respiration.

Mammals

There are almost more than 4,000 unique types of mammals. The littlest is the hog-nosed bat, and its weight is 0.05 ounces. The biggest is the blue whale that is 100 feet long and has weighed 150 tons. In any case, whether they live ashore or water, all mammals are vertebrates, endothermic, also known as warm-blooded animals. They can manage their particular body mildly, which permits them to live in each climate on Earth. They have hair on their bodies. They produce milk to bolster their young ones. It allows them to spend more energy with their young ones and show them essential skills which help them to survive.

Reptiles VS Mammals

  • Category

Reptiles include animals:

  • Turtles
  • Lizards
  • Tortoise
  • Crocodiles
  • Snake
  • Alligators
  • Tuatara etc

Mammals are divided into three categories:

  • Monotreme
  • Marsupials
  • Placenta

  • Epidermis

Reptiles have epidermis that is secured with scales.

Mammals have epidermis that is covered with hairs.

  • Heart

Most reptiles have a three-chambered heart: right auricle left auricle and ventricle.

Usually, mammals have a four-chambered heart: right atrium, left atrium, right ventricle, and left ventricle.

  • Metabolic rate

The metabolic rate of reptiles remains low.

Their metabolic rate of mammals remains high.

  • Diaphragm

Reptiles don’t have diaphragm for the respiration process.

Mammals have diaphragm for their respiration process.

  • Young ones

Reptiles are oviparous as they lay eggs, and their young ones get very little attention and care from their parents.

Mammals are viviparous as they give birth to their young ones, so in this way, their young ones get more attention and care from their parents.

  • Growth

Reptiles continue to grow throughout their life span.

Mammals usually grow till their adulthood, unlike reptiles.

  • Brain

Reptiles have a skull that has a little braincase. Their cerebrum has only one occipital condyle.

Mammals have skull which has an extended braincase. Their cerebrum is a larger and frequently little convoluted skull, which has two occipital condyles.

  • Jaw

Reptiles’ jaw is composed of many bones.

Mammals’ jaw is composed of a single bone.

  • Ear

Reptiles have only one bone of the middle ear, which is similar to stapes.

In mammals, there are three bones of the middle ear that includes: malleus, incus, and stapes.

  • Teeth

Reptiles continually replace teeth with simple cheek teeth.

Mammals can only produce two sets of teeth: ‘permanent and deciduous,’ also they have complex cheek teeth.

  • Heat

Reptiles take heat from external sources such as the sun.

However, mammals can produce heat in their body.

  • Cold or warm-blooded

Reptiles are cold-blooded animals or ectothermic.

Mammals are warm-blooded animals or endothermic.

  • Nutrition

Reptiles don’t help their young ones by providing nutrition.

In contrast, mammals provide nutrition in milk form to their young ones.

  • Bones

Reptiles have pelvic bones that are separated.

In contrast, mammals have pelvic bones that are fused.

  • Placenta

Reptiles do not have a placenta.

Mammals produce a placenta.

  • Mammary glands

Reptiles do not have mammary glands.

Mammals contain mammary glands that help to produce milk to feed their young ones.

  • Cognitive abilities

Reptiles contain a low level of cognitive abilities.

Mammals contain a high level of cognitive abilities.

  • Bony plate

Reptiles have an incomplete bony plate.

Mammals have bony plates that separate the mouth completely from the nasal passage.

  • Limbs

The limbs of reptiles horizontally emerge from the body.

The limbs of mammals are placed beneath the body.

  • Ribs

Reptiles contain ribs on all vertebrae.

Mammals contain ribs constricted to thoracic vertebrae.

  • Locomotion

Reptiles contain a sprawling gait.

Mammals contain upright stance locomotion.

  • Color

Reptiles can change its color anytime to any other color- multiple colors.

Mammals cannot change their color and remain the same- single colors.

  • Life span

Reptiles can live more than animals, even without food. A snake can live up to a year without eating anything. They require less energy.

Mammals cannot remain alive without having food for much time. They require more energy to live.

  • Sex organ

Reptiles contain internal sex organs and appear only at the time of sex.

Mammals have an internal sex organ.

Conclusion

From the above article, we come to know that reptiles are cold-blooded animals and have scales on their epidermis and usually have no diaphragm for respiration. In contrast, mammals are warm-blooded animals and have hairs on the epidermis and mostly have diaphragm for respiration. Reptiles have three-chambered hearts and less metabolic rates, whereas mammals have a four-chambered heart and more metabolic rate. Reptiles lay eggs, whereas mammals give birth to young ones. Reptile’s skull has a little braincase and one bone in the middle ear. Mammals have extended braincase, and three bones of the middle ear are there. Reptiles have unlimited growth, while mammals have limited growth. Reptiles can change their color, which mammals cannot do. Reptiles do not provide nutrition to their babies, while mammals provide nutrition by feeding them milk. Is there any  aspect left for their comparison according to your point of view?

References

https://www.austincc.edu/sziser/Biol%201413/1413%20handouts/reptile%20vs%20mammals.pdf

https://pediaa.com/difference-between-mammals-and-reptiles/

https://tailandfur.com/difference-and-similarities-between-mammals-and-reptiles/