Similarities and Differences between Oviparous and Viviparous Animals
There is a vast diversity of living life forms on the earth. The main living life forms are animals and plants. All living beings vary in their shape and structure. Some animal are little, some are large, some animal live on land, some live in water. In short, their structure and shape assist them to remain alive under various states of condition. All animal grow but perish after a definite period of life. Therefore, animal reproduction is essential for the survival of a species. Sexual reproduction is the process by which animals produce offspring, for the purpose of populating the species, by combining genetic information from two individuals of different types (Bonner, 1998). In general, animal reproduction can be divided into two methods: Oviparous and Viviparous. (Refer to Figure 1 in Appendix 1)
Oviparous animal refer to the animal that lay eggs; the development and incubating of the offspring happen outside the female body. The fertilization of the egg may happen either internally or externally. Birds, reptiles, amphibians, most fish, insects, mollusk, arachnids, and monotremes are example of oviparous animals (Panawala, 2017). Some of these animals produce nests to protect their eggs. However, a few oviparous animal, sharks and snakes for instance, whose eggs hatch inside the female body and live young ones are expelled. Oviparous animal has a less chances of survival because the eggs are laid in open environment and the nutrients absorbs by the embryo from the egg yolk itself. (Rachna C, 2018). Being an oviparous has it on disadvantages which is they have to protect and hide their eggs during development because the eggs produce is so fragile and also to protects those eggs from predators (Mills,2018)
Viviparous animals refer to the animals that give birth to offspring. Special organs posed by these animals supplied nutrients for the maturation of the embryo inside the female body. Some fish, amphibians, reptiles, and mammals are an example of viviparous animals (Panawala, 2017). Commonly, viviparous animals set aside a longer time to care for their young ones. Some young animal, for example, dolphins remain with their mom for a considerable length of time. Because of this minding of moms, viviparous creatures demonstrate a more prominent survival. The embryo absorbs nutrients inside the mother’s womb by this reproduction method (Rachna, 2018). Transition stages which occurs after egg is fertilized play a very important role in viviparous mammals which they can experience discomfort, potential health risks and also increase in size of their uterus (Turner, 2018).
One of the differences between oviparous and viviparous animals is the chances of survival. Oviparous animals reproduce by deposit egg in external habitat which also brings risk as the egg can be attacked by the predators and any minor physical damage can lead to the death of progeny. Chances of survival are less for oviparous offspring although the egg is protected by hard shell around it (Panawala, 2017). Viviparous offspring had more chances of survival as it is develop inside the female body and shield from external danger. Besides that, oviparous and viviparous animals have different ways to nourish the embryo. Embryonic development takes place inside the mother womb for viviparous animals where directly it gets all the food, nourishment, shelter and protection. Rachna (2018) stated that viviparous animal have special organ which provide nutrients for the development of the embryo, the process is called Matrotrophy In oviparous animals, nutrition of the embryo is provide exclusively by the yolk. Thus, females of some oviparous species will retain eggs in order to keep them warm until the embryo are ready for the hatching (Cabej, 2012). It is to ensure the moisture needed for proper embryo development. (Smith, 2004). In short, oviparous gain nutrient for embryo from yolk while viviparous received nutrient directly from the mother.
There are several similarities between oviparous and viviparous animals which are internal fertilization can take places in both animals produce. The process of the oviparous animals to produce their progeny is known as oviparity (Rachna, 2018). The growth of the eggs undergoes inside the female’s body and the eggs fertilised either internally or externally. While for viviparous animals, embryonic development occurs inside the female reproduction tract. Rachna (2018) also stated that the internal fertilisation of the viviparous animal involving the both of male and female germ cell inside the body. Typically, both oviparous and viviparous animals are involved in internal fertilization. Other than that, oviparous and viviparous animals have reproductive strategies of the production of young ones (Blackburn, 1999). Oviparity is a pattern in which females lay eggs that hatch in the external habitat. In contrast, viviaparity is a reproductive pattern in which development of eggs is retain inside female productive tracts before deliver out the offspring. These pattern is viewed as “productive strategies” as stated by the Blackburn in 1999.
To summarize, oviparous and viviparous animals are two groups of animals that populating differently. The methods of the development of the young ones are the main difference between oviparous and viviparous animals. While the main similarity between oviparous and viviparous animals are both will produce offspring for the survival of the species.
Blackburn, D. G. (1999). Vivaparity and oviparity: Evolution and reproductive startegies.xxxxxxBonner, J.T. (1998). Reproduction. Retrieve from https://www.britannica.com/science /reproduction-biologyPanawala, L. (2017). The difference between Oviparous and viviparous. Retrieved from https://www.researchgate.net/publication/320516607_Difference_Between_Oviparoand _Viviparous
Rachna, c. (2018). Difference between oviparous and viviparous animals. Retrieved from https://biodifferences.com/difference-between-oviparous-and-vivparous-animals.html
Smith, T. W. (2004). Care and incubation of hatching eggs. Sheffield, England: Benchmark Holdings.
Mills,A. (2018). What Are Oviparous Animals?. Retrieved from https://www.animalwised.com/what-are-oviparous-animals-2816.htmlTurner,F,J. (2018). Viviparous Animals. Retrieved from https://www.animalwised.com/viviparous-animals-2548.html