In nature there is a great variety of animals and species with unique behaviors and qualities. In order to establish a classification, it is possible to divide them according to their characteristics, whether they are reptiles, birds, fish or amphibians. However, as incredible as it may seem, there are cases where a species shares characteristics of both one class and another.
This time, on our site, we will talk about the mammals that lay eggs, their characteristics and examples. Sound a bit strange? But they exist! Find out what they are!
Do mammals lay eggs?
In principle, most mammals, including humans, have a type of reproduction sexual, in which male and female cells from two different individuals are necessary for fertilization to occur and, therefore, for a new life to begin. However, there are some mammals that reproduce by means of eggs These belong to the order monotreme This order includes all those mammals that, at the same time, have reptilian characteristics; among them, oviparous reproduction. This type of reproduction is carried out thanks to the existence in the body of individuals of an orifice called the cloaca, which fulfills the functions of the digestive, urinary and reproductive systems.
On the other hand, monotremes or monotremes, as they are also known, not only possess reptilian characteristics, but also share qualities with their fellow mammals, such as the following:
- They are animals homeotherms,that is, they can maintain their body temperature within certain limits.
- The surface of your skin is covered with hairs.
- They feed their young through the milk produced in their bodies.
- Have diaphragm.
- Your heart is divided into four cavities.
Thanks to all this, characteristics of completely different animal orders appear on the body of these peculiar species, making them quite rare specimens. Now, do you want to know which are the mammalian animals that lay eggs? There are only two! Discover them below!
Egg-laying mammals: platypus
The platypus, whose scientific name is Ornithorhynchus anatinus, has a curious appearance that suggests that it was formed from parts of different animals. At first glance, you can guess that it has the beak of a duck, the webbed feet of an otter, a tail just like a beaver's and, to top it off, quite thick and bushy fur! And that's not all! Incredible as it may seem, the platypus is a poisonous animal, since it has a spur on its hind legs that it uses to defend itself against predators. Its fur is dark brown with gray or yellow spots; As the threads are so thick, they protect it in the water, where it spends much of its life. Most specimens measure 60 centimeters and weigh about 3 kilograms
Regarding its habitat, the Ornithorhynchus anatinus is native to eastern Australia and lives in burrows or on riverbanks. It feeds on insects and other invertebrates that it catches through a method called electrolocation With this method the platypus is able to perceive the weakest electrical impulses that other animals produce when moving.
As for their reproduction, as we said, females lay eggsthat first form in the uterus and then are incubated for a period of approximately 10 days. In general, they do not usually put more than three, with two being the most common figure. Once hatched, the little ones feed on mother's milk which, curiously, they don't express through the mother's nipples, because they don't have nipples! In this way, the females have mammary glands but secrete milk through pores in their skin and through which the young can lick it. If you want to discover more curious facts, don't miss the article "Curiosities about the platypus".
Egg-laying mammals: Echidna
Another mammal that lays eggs is the echidna or Tachyglossidae. This is an animal with a robust body, surrounded by long spines about 7 centimeters long in length, which also has short hair that covers it and no tail. Its appearance, at first glance, is very similar to the hedgehog
Like many other animals, the echidna's defense system is its spines, which it uses by burying the rest of its body and offering its predators as if it were a coat of spines. There are two species of echidna: the common or short-beaked echidna and the long-beaked echidna.
Only inhabits the island of New Guinea and Australia. It is a nocturnal animal, so during the day it usually hides among rocks, holes, tree roots and bushes. It is a very good swimmer and feeds especially on insects, which it locates through its sense of smell; his sight, on the other hand, is very limited. Another of the hunting mechanisms of this species is its sticky tongue. It measures 20 centimeters in length and uses it to capture its prey. The echidna does not have teeth, so it grinds its food with a kind of horny spines that are located on the palate at the end of the mouth.
Like the platypus, the echidna belongs to the monotreme group, so its reproduction is oviparous like birds, but it feeds its young through mammary glands like any other mammal.
Now that you know the two mammals that lay eggs, don't miss the following articles to broaden your knowledge about the animal world:
- Classification of living beings into 5 kingdoms
- All about omnivorous animals
