Animals

20 Examples of Oviparous Animals

Ovoviviparous animals are a mixture between oviparous animals (which lay eggs) and viviparous animals (which develop inside the female's womb). Ovoviviparous animals develop and grow inside an egg that the mother keeps inside her body and takes care of it until it hatches.

The shark is an ovoviviparous animal

Table of Contents

Reproduction and adaptation

The fertilization is internal, like the development of the embryo, but unlike the viviparous animals, this is done inside an egg, where it is protected by the female. Inside the egg they feed on the nutrients provided by the same egg.

There are animals where the egg breaks inside the mother and they are born alive and adapted to the world around them. We also have animals where the female ejects the egg and they wait to hatch, once hatched the female takes care of them until they are self-sufficient.

How are the oviparous?

In the case of oviparous animals, fertilization can occur inside or outside the female's body. Breeding development, then, takes place outside the mother's body. Oviparity is characteristic of birds, fish and amphibians. Some reptiles, such as turtles and snakes, and many insects are also oviparous.

That breeding takes place inside an egg is considered a evolutionary advantage which tends to improve the survival rate, because the structure of the egg protects the embryo and prevents desiccation, which can be very relevant in warm regions.

There is a mixed category, which is that of Ovoviviparous In this case, the eggs remain inside the female's body until the embryo is fully developed. Certain sharks and various invertebrate animals make up this category.

  • See also: What are viviparous animals?

Oviparous and caring for their eggs

Not all oviparous animals handle their eggs in the same way. Almost all place them in nests. While birds often build their nests in trees or on the ground, where they hatch, other animals, such as turtles, bury their eggs in the sand.

The fishes and the amphibians, on the other hand, they lay their eggs in the water. Penguins also lay eggs. Generally these eggs are covered by a gelatinous layer that protects them.

They are usually translucent and quickly incubated, from them emerge the so-called fry, which feed on the yolk sac of the egg.

Examples of ovoviviparous animals

  1. White shark: A type of large and robust shark. It has an arc-shaped mouth. You must swim constantly (you cannot remain still) to be able to breathe and to be able to float, since you do not have a swim bladder. The embryos feed through the vitellium. This shark does not lay eggs but the young hatch into the mother and then are born developed.
  2. Boa constrictor: Reptile which can measure between 0.5 and 4 meters, depending on the subspecies. In addition, females are larger than males. It is reddish and white, or reddish and brown, with variants depending on the subspecies. It pairs in rainy season. Its gestation lasts several months. The hatching of the eggs occurs within the mother's body, with already developed offspring being born.
  3. Mielga: Type of small shark, which reaches a little more than one meter in length. It is characterized by having poisonous spines on the surface of the body. It is the most abundant shark species but with a restricted distribution. The reproductive litter depends on the size of the female, since the usual is 1 to 20 embryos per pregnancy, but larger females can have more numerous litters. They are born out of the egg.
  4. Stingray (giant blanket): It is distinguished from other species because it does not have a poisonous sting in its tail. Also for its large size. He lives in temperate seas. It is able to jump out of the water. At the time of reproduction, several males court a female. In order for one of them to reach the intercourse, he must kill his competitors. It is estimated that the time that the eggs remain within the female can be more than twelve months. They have one or two young per litter.
  5. Anaconda: Constrictor snake genus. It can reach ten meters in length. Although he does not live in a group but alone, when the female wants to reproduce it can attract the male releasing pheromones. Each litter is born between 20 and forty offspring approximately 60 cm long.
  6. Suriname toad: Amphibian that inhabits tropical and subtropical areas. It is characterized by its flat body and its flat and triangular head. Its color is slightly green gray. It is a special type of ovoviviparous animal, since fertilization occurs outside the mother's body. Once fertilized, the female returns to enclose the eggs in her body. Unlike other amphibians, which are born as larvae and then undergo metamorphosis, this toad performs its larval development inside the egg, and the individuals that are born already have their definitive form.
  7. Platypus: It is considered a mammal, but it lays eggs, so it can also be classified as an ovoviviparous. It is a semi-aquatic animal that lives in eastern Australia and in Tasmania. It is characterized by its particular appearance, with a snout that resembles a duck's beak, tail similar to that of the beaver and legs similar to the otter. It is poisonous.
  8. Jackson Trioceros: Ovoviviparous chameleon species. It has three horns, that's why it's called "trioceros." He lives in East Africa. They are born in litters of between 8 and 30 specimens, with a gestation of up to six months.
  9. Hippocampus (seahorse): It is a particular type of ovoviviparous, since the eggs do not ripen inside the female's body but in the male's body. Fertilization occurs while the female passes the eggs to the male's sac. The sac is similar to that of the marsupials, that is, it is external and ventral.
  10. Lución (Crystal shingles): Very particular animal, since it is a lizard without legs. That is to say that in appearance it is similar to a snake. However, it is known that it is a lizard because there are traces of its skeleton in its body that has the characteristics of lizards. In addition, it has mobile eyelids, unlike snakes. It is a reptile that lives in Europe and can measure up to 40 cm, or 50 cm females. Reproduction occurs in spring. After 3 or 5 months of gestation, the female lays eggs with mature offspring inside, and hatching occurs immediately.

1) Ovoviviparous snakes

Not all snakes are ovoviviparous, but if some examples, such as Boa constrictor. It is a large reptile, capable of reaching 4 meters in length in your adult stage. It is native to the wooded areas of America, from Argentina to the northern part of Mexico. Their colors are brownish, brown and red, with a beautiful design on their skin.

In this case the females are larger than the males, and once they mate, the female harbors the eggs in her abdomen until the moment of birth. The pregnancy lasts about 4 months, during which the boa darkens its color to have more energy, absorbing more heat from the sun. The young hatch into the mother, and when she gives birth, perfectly formed small snakes are born.

2) The pike, an ovoviviparous lizard

The glass shingles is a legless lizard that lives in areas of Europe and Asia. It is small in size, and measures between 30 and 40 centimeters. People can confuse it with a snake, but in reality it is a lizard that during its evolution lost its legs, of which there are only small skeletal skeletal remains. Unlike other lizards, he is not a friend of the sun, and prefers shadow and night to move. It is a great ally of the farmers, since it feeds on worms and limacos.

They mate in spring and After 3 to 5 months of gestation, the female lays eggs with fully developed offspring inside.Immediately after laying, perfectly developed offspring hatch.

3) Jackson's trioceros

It is an ovoviviparous chameleon, which lives in Africa, in cold and wet areas of Kenya and Tanzania. They have 3 horns on their heads, and hence their name, They are bright green, with traces of blue and yellow. Some people have trioceros as pets, although they need very specific humidity and temperature conditions, so they don't get sick.

After mating, the gestation is long, and the female can carry the eggs in her body for 5 or 6 months. At birth, the mother stops between 8 and 25 offspring.

4) Suriname's toad

Also called "cell frog" is an amphibian of about 15 centimeters, which lives in swamps and ponds in the tropical regions of South America. Its color is greenish gray, paler in its belly.

Its reproduction is very particular. The fertilization is external, and takes place in the water, but when the eggs are already fertilized, the female encloses them in her body again, in some special cells you have on your back, (hence its name). These are holes in the skin of the mother toad, which will house the eggs while the embryos grow for 12 weeks. Instead of hatching like tadpoles, Suriname's toad hatches as a small adult, emerging from the back of his mother. That is, that larval development and metamorphosis occur inside the egg, inserted into the skin of the female. It's a pretty shocking scene, which you can see below in this video.

Frog of cells "giving birth" to their young:

5) The salamander a special oviparous

The salamander is a small amphibious animal, black with yellow spots that it has developed two different reproductive strategies. The first consists of mating, storing the eggs in the female's body, and then laying. Just lay the eggs in the water, larvae that are carnivorous are born. They spend four months feeding and then they do their metamorphosis, just like other amphibians Like frogs Only after 2 to 4 years, salamanders will have their final adult form and have reached sexual maturity.

The reproduction of the salamander has a second variant. Some species, such as those that live in Cantabria and the Pyrenees (Spain), They mate and carry their eggs inside the female's body for longer. At the time of childbirth, small salamanders are born already metamorphosed, and not aquatic larvae. This reproductive strategy is believed to have arisen in specific areas where it was difficult for salamanders to find suitable water ponds for their tadpoles.

6) Ovoviviparous sharks like the white shark

The White shark is huge, measuring between 5 and 7.5 meters, and has a formidable arc-shaped mouth. They live in the temperate waters of almost all oceans. They are carnivores, and feed on bluefin tuna, sea turtles and marine mammals such as the monk seal, which they hunt by ambushing them. He cannot remain still, but must constantly swim in order to breathe.

White shark reproduction is ovoviviparous. The female houses in her womb between 4 and 10 eggs, which hatch inside and remain there for a while. It is believed that the strongest shark offspring eat the weakest and the eggs that have not hatched. This is called «Intrauterine cannibalism». In the end 3 or 4 perfectly formed pups are born, about 12 centimeters long, with small sharp teeth like saws. As soon as they are born, they move away from their mother, and begin their independent path, which they will take alone throughout his life.

7) The blanket stripe

The stripe is a giant sized blanket, which lives in temperate waters around the world, and is characterized by not having poisonous sting in its tail. The manta ray eats plankton, small fish and squid.

During courtship, several males approach the female, and the winner sometimes kills the others. The fertilization of the eggs is internal, using the male a sperm transmitting organ. The Manta ray is ovoviviparous, and fertilized eggs remain within the female for a long period, between 9 and 12 months. After this time, stop only one or two offspring, which measure around 1.2 meters in length.

8) The seahorse a special ovoviviparous

The seahorse or hippocampus, is a species of fish with a peculiar reproduction. The female drops the unfertilized eggs in the water, and the male picks them up and keeps them in a bag special in your abdomen, similar to that of the marsupials. At the same time it fertilizes them, in a process that lasts a few seconds.

Once you have all fertilized eggs, the male keeps and protects them inside, until the eggs are ripe and the little horses are born. We have said that normally the ovoviviparous lay few eggs, but the hippocampus is an exception, since the male can give birth to up to 2,000 small young. During the following days, the male keeps taking care of them, and the little horses come in and out of his bag at will, every time they feel there is danger.

Look here the birth of a seahorse (male giving birth):

The gestation in the viviparous

The gestation period of the viviparous it varies according to the species and this depends, among other things, on the size of the animal. That is, the period of an elephant will be significantly longer than that of a mouse, to give just one example.

Another issue that varies by animal is the number of offspring that a female can conceive every time she becomes pregnant. For example, a rabbit has many more young than the human being.

In most cases, the breeding of viviparous animals develops in the placenta. It is there where the breeding manages to stock up on the nutrients and oxygen that are necessary to stay alive and develop its organs, until the moment it is born.

Anyway, within the viviparous we can identify a small group of animals, such as kangaroos or koalas, which are called marsupials and that they differ from the rest just by not owning placenta. But the breeding, which is born very poorly developed, ends up being shaped as such in the so-called "marsupial bag."

  • It can serve you: Carnivorous animals

Examples of viviparous animals

  • Rabbit: Your pregnancy time is generally less than 30 days.
  • Giraffe: its gestation period lasts about 15 months.
  • Elephant: these mammals have pregnancies that last between 21 and 22 months.
  • Cat: The gestation time of these animals is approximately 60 to 70 days.
  • Mouse: An animal like this does not spend more than 20 days in the womb.
  • Bat: The pregnancy period of this animal is between 3 and 6 months, depending on the cases.
  • Dog: 9 weeks is what lasts, approximately, the pregnancy of these animals.

  • Whale: The pregnancy of an animal like this can last up to a year.
  • Bear: The pregnancy of this wild animal can last up to 8 months.
  • Pork: The gestation period of this farm animal is around 110 days.
  • Horse: These animals have a pregnancy that lasts approximately 11 or 12 months.
  • Cow: before giving birth, this ruminant is about 280 days pregnant.
  • Sheep: A sheep must be about five months pregnant before giving birth to her baby.
  • Koala: The pregnancy itself of these marsupials lasts approximately one month. Although it should be taken into account that the breeding is not fully developed, but continues to form in the marsupial bag.
  • Chimpanzee: These animals have a gestation period that lasts a little less than 9 months.
  • Dolphin: these mammals have a gestation period of around 11 months.

  • Kangaroo: In this type of marsupials, the pregnancy lasts about 40 days. As in the case of koala, the development of the breeding is prolonged outside the maternal womb, in the marsupial bag.
  • Chinchilla: The gestation period of these rodents is approximately 110 days.
  • Donkey: The pregnancy of these animals lasts approximately 12 months.
  • Rhino: The pregnancy of these animals is one of the longest, since it can last up to a year and a half.