In nature, the methods of reproduction are different in animals. There are several ways, depending on whether the animals are oviparous, viviparous or ovoviviparous. What is the difference between oviparous, viviparous and ovoviviparous? We give you a clear summary of these three categories of animals and how to ensure their reproduction.
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- Oviparous, viviparous and ovoviviparous
- animals Oviparous
- animals Examples of oviparous
- The case of lizards and snakes
- Viviparous animals
- Examples of viviparous animals
- Ovoviviparous animals
- Examples of Ovoviviparous animals
- An exception for breeding: sharks
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Oviparous, viviparous and ovoviviparous
Animals are generally classified according to their reproductive system. An animal has a single mode of reproduction , which may be either oviparous, viviparous or ovoviviparous.
It is impossible for animals to combine breeding modes, except for some exceptions (see below). Generally speaking, this is necessarily one of the three modes presented. Here are in detail the modes of reproduction observed in nature.
Oviparae are animals that lay eggs and exclusively eggs to ensure the reproduction of species. This implies that an embryo grows outside the mother’s organism . This growth is done in the egg once fertilization is done.
Examples of oviparous animals
Animals that lay eggs are, typically, the whole family of gallinaceae, that is, chickens. Birds and many other animals such as turkey, geese or ducks, are of course oviparous.
Other oviparous ones include turtles, crocodile family, fish and insects are also oviparous as they lay eggs.
In order not to be mistaken, you can remember that one oviparates begins with the letter o , as an egg. The o also reminds of the shape of the egg.
There are, however, two exceptions, in oviparous mammals are the case of ornithorynus and echidne. These animals are breastfeeding, so they are mammals. They also lay eggs, and they are the only mammals known to be oviparous. These oviparous mammals should not be confused with “ovoviviparous”.
The case of lizards and snakes
Lizards and snakes can either be oviparous or ovoviviparous. As an example for the lizard oviparous , we have Madagascar gecko, but also iguanas and varans (Komodo dragons).
The best-known oviparous snakes are python, cobra, black mamba, snake, taipan. In these cases, the female lays and then leaves or protects her eggs by wrapping around.
Vivipares are animals that give birth to young animals already formed. The embryo of the animal carries out all its growth in the womb of the mother . The embryo is fed directly by the umbilical cord. Human beings are viviparous mammals.
Examples of viviparous animals
Animals that give up, such as cats, dogs, horses, goats, elephants or tigers, are viviparous animals.
In reality, almost all mammals are viviparous . This includes large animal families:
Celines, canids, cetaceans, bovids, deer, camelids and many others.
The third category is the most curious and can be confusing. Ovoviviparous animals are animals that give birth to young people who are already trained. They developed and grew in eggs that hatched inside the mother or female. The embryos of these animals feed without an umbilical cord.
Examples of ovoviviparous animals
We mentioned the ovoviviparous snakes, which are the viper, the rattlesnake, the anaconda, the boa and the smooth coronella . Once the small snakes come out of the body of the mother/female, they are already trained and ready to survive autonomously. They own their fangs in particular venom.
The sharks listed below in the exceptions are ovoviviparous: white shark, saw shark and tiger shark . These sharks are born in eggs, inside the mother, after they grow warm. Eggs hatch and small sharks are ready to swim and survive.
A breeding exception: sharks
Yes, some sharks have the three modes of reproduction combined. The shark is a cartilaginous fish that can change its mode of reproduction.
Bulldog shark , hammerhead shark and blue shark, for example, are viviparous.
The bird and the carpet shark are not viviparous but oviparous: they lay their eggs.
Tiger shark , white shark and saw shark are known ovoviviparous.
Animals are curious species that never end up fascinating. Systems and modes of reproduction sometimes even lead to large questions. In 2016, a female zebra shark in captivity made babies all alone. This is a rare phenomenon that is called parthenogenesis .
Indeed, the aquarium was populated only by female sharks. Would the female shark have been able to store sperm from the male shark from which it had been separated 3 years earlier? The mystery remains complete and raises questions about the instinct of survival of captive animals.
This phenomenon is studied closely and suggests the beginnings of theories about the evolution of species according to what they are led to live. Are wild animals also capable of such exploits? The phenomenon of parthenogenesis, coming from a shark mother, gives birth to female shark. So this is a reproduction asexual , another mode of reproduction that remains totally minor (as we know) in the wild and in the wild. Business to follow!