Reproduction Is A Essential Step For The Sustainability Of All Living Things, And The Consequences Of Unsuccessful Reproduction

1784 Words Nov 4th, 2014 null Page
Reproduction is a vital step in the sustainability of all living things, and the consequences of unsuccessful reproduction can be catastrophic for a species. Therefore, it is not surprising that multiple strategies have evolved over time in order to ensure offspring will be viable and competitive members of a population. One of the basic features of reproductive success is providing offspring an environment with the necessary features for effective development, such as nutrients and water, temperature control and protection from predators. Oviparity and viviparity are two methods that provide developing embryos with the environment they require to successfully develop. Oviparity can be defined as a reproductive mode where a portion of embryonic development occurs in an egg, independent from and external to the female (Guillette, 1993). In comparison, viviparity is generally defined as the embryo fully developing in the womb, culminating in a female giving birth to developed offspring. A third term, ovoviviparity, also exists and is defined as an embryo, inside of an egg and only nourished by yolk, being retained and hatching inside of the female. However, no examples of this are known to exist and therefore this mode is considered to be impossible for reptiles. Some flexibility exists in these definitions, which is needed to address cases that are not clear cut. For example, Sphenomorphus fragilis lays eggs that hatch hours after being laid, but all of the development occurs…

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