Difference between Oviparous and Viviparous

There are a variety of animals, plants, shrubs, etc., on this earth. Animals, plants, and humans have different ways of sustenance.

Some animals sustain on plants, some sustain on the flesh of other animals, etc. There are different ways in which they live. Apart from sustenance, reproduction is an important part of nature. Humans, animals, and plants reproduce in order to give birth. Now, plants, animals, and humans reproduce in different ways. So today, we will be discussing about two significant kinds of reproduction. They are oviparous and viviparous. Animals reproduce through these two kinds of reproduction. Well, there are some scientific facts regarding these two terms, but let us first begin with the meaning of these two terms, followed by their differences.

Oviparous

Oviparous is defined as the process of reproducing through laying eggs. The etymology of the word oviparous dates back to the year 1646. The word oviparous has been derived from the Latin word 'oviparus.'. The process of embryonic development and fertilization does not occur inside the parent's body. The offspring hatch outside the mother's body.

Reptiles, amphibians, fishes, dinosaurs, birds, etc., are oviparous animals. They reproduce by laying eggs. It is interesting to note that arachnids, insects, etc., are also oviparous animals. Birds like ducks and hens carry immature embryos within them. The eggs of these animals are made with hard shells that are difficult to be destroyed. The embryonic development takes place externally, but fertilization occurs internally. Once the embryo becomes mature, the egg hatches.

The traits shown by the oviparous animals are called oviparity. The eggshells of oviparous animals are made with calcium. Some species of snakes are not considered to be oviparous. There are two kinds of mammals that are considered to be oviparous, i.e., echidna and platypus. Well, it is interesting to note that amphibians, particularly frogs, lay their eggs in a moist environment because they need constant hydration. In oviparous animals, the nutrition reaches the embryo through the yolk material in the eggshells. This material is provided by the mother's reproductive system. This condition is called 'Lecithotrophic.' Generally, mammals do not lay eggs. There are only five kinds of mammals that lay eggs. They are the duck-billed platypus, western long-beak echidna, short-beak echidna, eastern long-beak echidna, and long-beak echidna. Interestingly, these mammals are only found in New Guinea and Australia.

Viviparous

Viviparous is defined as the process of producing young offspring. These offspring develop inside the parent's body instead of hatching from the eggs. In botany, viviparous is defined as the process of reproducing from the buds. These buds form plantlets that are attached to the parent plant. These buds can also be attached to the seeds that might germinate in fruits. In terms of animals and humans, embryonic development occurs inside the mother's womb. Unlike the oviparous animals, the viviparous animals do not have a protective covering. Examples of viviparous animals include dogs, cats, cows, rabbits, etc. the embryos develop into the fetus in the mother's womb. These animals reproduce through internal fertilization, wherein the fertilized eggs are developed. Viviparity differs in different animals and humans. For instance, the lifespan of a human is 79 years.

Similarly, the lifespan of horses and cattle is 22 years and 30 years, respectively. The gestation period, mass, height, length, speed, etc., are different in all viviparous animals. The gestation period of cattle is 283 days. Likewise, a horse has a gestation period of 12 months. There are four modes of reproduction in viviparous animals, namely histotrophic viviparity, hemotrophic viviparity, ovoviviparity, and placental viviparity. Metamorphosis occurs in viviparous animals. All the organisms grow and become adults. This process of development is called metamorphosis. Silkworms, butterflies, cockroaches, etc., are examples of metamorphosis. Now, there are certain differences between viviparous and oviparous. So, let us discuss them in brief.

So, these are some of the contrasting points between oviparous and viviparous. There is just one similarity between oviparous and viviparous animals, i.e., both undertake the process of internal fertilization. Now, there are certain differences between viviparous and oviparous animals. So, let us have a look at them.

Characteristics of Oviparous Animals

1. Oviparous animals give birth outside their body.
2. Internal fertilization takes place in the body.
3. The embryo develops into a fetus inside the egg.
4. The eggshell has a strong covering of calcium.
5. The offspring are born on the ground after internal fertilization and embryonic development.

Characteristics of Viviparous Animals

1. Viviparous animals give birth to younger individuals.
2. Internal fertilization and embryonic development take place inside the mother's body.
3. There is no hard covering outside the embryo to protect it.
4. The chances of survival and sustenance are more in viviparous animals.
5. Humans also come under the category of viviparous.

So, these are some of the prominent characteristics of oviparous and viviparous. The process of reproduction is different in both kinds of animals. However, oviparous animals have less chances of survival, unlike viviparous animals. Thus, both oviparous and viviparous animals differ in growth, development, and maturity.