Difference Between Oviparous and Viviparous Animals

The animal world is flooded with a lot of diversity. One can easily see these differences by comparing two individuals of different phylum (or even in the case of orders) if we talk about Fertilization (The fusion of male and female gametes). We can see some marked differences. On a broad basis, Fertilization can be of two types:

• External Fertilization: – Sperm and egg meet outside the female body through different modes, e.g., Frogs, fishes, etc.
• Internal fertilization: – Sperm and egg meet inside the female body, e.g., Human, cattle, Dog, etc.
  • A marked difference can also be seen in the later development of these organisms. In the case of Internal fertilization, the organisms can broadly be classified into three categories. 
    • Oviparous
    • Viviparous,
    • Ovoviviparous

Oviparous Animals

Oviparous is a Latin word that originates from “Ovo- means egg + pario- means give birth’’. These are the animals that lay eggs directly. These are the fertilized eggs; regardless, fertilization can take place outside or inside the female body. Furthermore, embryonic development always occurs inside the egg and outside the female body. The eggs contain all the nutrients in form of yolk and albumin protein which helps the gamete to fully develop into an organism. The eggs laid by these organisms can be small and fragile, e.g., the egg of a Chick, or large and strong, e.g., the egg of an Ostrich. The number of eggs laid by the female depends from species to species. Some of these organisms protect their eggs from predators by hiding them, e.g., Cuckoo; also, some organisms sit on them and keep them warm, e.g., Chick. 

Viviparous Animals

Viviparous is a Latin word that originated from ‘’Vivus-means alive/life + pario- means give birth’’. These animals directly give rise birth to their offspring. Fertilization takes place inside the female body, and the female has a special organ, e.g., the Uterus in the case of humans, where the development and nourishment of the embryo take place (this condition is also known as matrotrophy). These organisms nourish the foetus with their body food reserves. They mostly reproduce once a year; some of them have breeding seasons, e.g., Dogs and cattle, and some can reproduce throughout the year, e.g., Human. Most of the viviparous organisms belong to the taxa vertebrate, while some examples have also been seen in some invertebrates. 

Difference between Oviparous and Viviparous Animals

S. No.	Oviparous	Viviparous
1.	Female Ley eggs outside the body.	Females give rise birth to young ones.
2.	Fertilization can be external or internal.	Fertilization always internal
3.	Egg contains yolk, albumin and essential supplements for the proper development of the young one.	The foetus obtains nourishment inside the female body through the food reserves of the female.
4.	Females provide protection to the eggs by hiding them from predators.	Females carry the foetus inside the body and can move away from predators.
5.	The survivability of the eggs is less due to which female lays more eggs.	The survivability of the foetus is high; females, most of the time, give birth to a single foetus.
6.	Females do not have Memory glands.	Most females have memory glands.
7.	Examples- are birds, reptiles, amphibians, most fishes, and insects.	Example- Mammals

Ovoviviparous

This term combines Greaks words; ”Ovum- egg + vivus-alive + barere- bearing forth or bear”.  In these organisms, the embryo develops inside the egg, which remains inside the female’s body until it hatches, e.g. sharks, snakes, insects and some amphibians. 

FAQs on the Oviparous and Viviparous Animal

Question 1: What are oviparous animals? 

Answer: 

• The word Oviparous comes from a combination of two Latin words that means “Ovo-egg + pario-give birth’’. These animals lay eggs directly; regardless, fertilization can occur outside or inside the female body.
• Also, embryonic development always occurs inside the egg and outside the female body. 

Question 2: Differentiate between internal and external fertilization. 

Answer:

When the sperm and egg meet inside the female body, this type of fertilization is called internal fertilization, e.g., in humans and cattle. Whereas, in the case of external fertilization, sperm and egg meet outside the female body through different modes, e.g., frogs, fishes, etc.

Question 3: Differentiate between Oviparous and Ovoviviparous? 

Answer: 

Oviparous are organisms that lay eggs outside in the environment, and the embryo develops outside the female body. Whereas in the case of Ovoviviparous, the embryo develops inside the egg and the female’s body.

Question 4: What type of fertilization can be seen in the case of Oviparous and Viviparous? 

Answer:

 Fertilization in case of 

• Oviparous: Internal or External fertilization depending on the organism.
• Viviparous: Internal Fertilization.