Animals are one of the greatest attractions that children can find since, especially for the little ones, discovering the variety and richness of the animal world is one of the most interesting and satisfying experiences they can have in childhood. For this, it is very interesting to know how to distinguish the different types of animals that exist, as well as the characteristics that are specific to each group. One of the cases where this differentiation is more complicated is that between reptiles and amphibians, since many children perceive that, at first glance, they are very similar to each other.
Why is it difficult to differentiate between amphibians and reptiles?
It must be borne in mind that, when differentiating between amphibians and reptiles, it is normal to become confused since, at first glance, they are two types of animals that present many similarities . On the one hand, they are animals of similar appearance, even in the colors of their own body, since many of them have greenish and brown tones, which makes them appear closer than they are. On the other hand, when we think of amphibians, one of the classic definitions of this group of animals is that they are animals that live both in water and on land. However, this definition could also be applied to many reptiles, which means that the dividing line between them cannot be established solely by the environment in which they live and develop.
In addition, if all the above were not enough, both types of animals reproduce through eggs, which makes it not seem easy to distinguish them by the way of reproduction. However, despite this, it is in the way of reproducing where we will find the first differences between one and the other.
As we have seen, both reproduce by means of eggs. Despite this, there are substantial differences between the eggs of amphibians and those of reptiles , which will give us a first idea of what characteristics make them unique and differentiate them from the others:
- The eggs of reptiles are eggs that pose one hard and impermeable shell , much like eggs that can be found in the kingdom of birds.
- On the contrary, amphibians have soft eggs without a hard shell to waterproof them, which makes their eggs look much more like fish eggs.
In fact, the difference is such that reptiles are called amniotes, that is, their embryos have a membrane that protects them during their development. On the contrary, animals that do not have this protective membrane, such as amphibians and fish, are called anamniotes, that is, without a membrane.
In addition, beyond the type of eggs that one and the other lay, another factor that differentiates amphibians and reptiles in the field of their reproduction is found in fertilization:
- In the case of reptiles , all of them have internal fertilization, that is, the male must deposit the semen inside the female for fertilization to occur.
- On the contrary, in the case of amphibians , we find both internal and external fertilization, that is, what happens when the females release the eggs into the water and, later, the males release the sperm on them for fertilization to occur. .
However, the differences between amphibians and reptiles go beyond the reproductive characteristics of one and the other. First of all, one of the easiest differences to observe is going to be found in your skin :
- In the case of amphibians , they have a moist, very soft and permeable skin.
- On the contrary, reptiles are characterized by having a skin formed from keratin scales, which is a substance present in many animals and which forms solid and resistant tissues, such as part of the nails and hair of mammals. , including humans.
Likewise, we will find another of the great differences between amphibians and reptiles in their offspring :
- Once these hatch from the egg, the young reptiles are fully formed. That is, despite their small size, they have fully formed bodies that will gradually grow into adults.
- On the contrary, amphibian offspring , at birth, will not have an adult body, but must go through different metamorphoses until they complete their biological cycle. A good example is found in frogs, which will be born as tadpoles, without back or front legs and with a tail. After several metamorphoses, it will be when they develop their legs and lose their tail, which will allow them to become adult frogs.
Finally, another of the characteristics that differentiates amphibians and reptiles is found in their way of breathing :
- In the case of reptiles , all of them, and throughout their life cycle, will only have lung respiration, adapted to life on land and to the oxygen present in the air.
- In contrast, amphibians will go through different phases of respiration. In the case of the youngest hatchlings, they will have gill respiration, just like fish and adapted to life in the water. On the contrary, it is only when they are adults that they will develop the pulmonary respiration typical of land animals, and, despite this, they will retain their skin respiration throughout their lives, which will allow them to take oxygen through the skin. in addition to doing it through the lungs.