What Does Oviparous Mean (In Sharks)?

Oviparous reproduction occurs when an animal reproduces through fertilized eggs. The eggs are fertilized inside the body of the female and laid prior to embryonic development.

What Are Oviparous Animals?

Oviparous animals lay their eggs before any embryonic development has started. One example of an oviparous animal would be a chicken. Along with chickens, the list of oviparous animals also includes many reptiles, fish, birds, monotremes, amphibians, and dinosaurs. 

Oviparous Reproduction Of Sharks

There are several shark species that lay eggs instead of birthing live young, but these species are the minority. The majority of shark species are viviparous, meaning that the fertilized egg undergoes some embryonic development within the mother’s body before being born. 

A Shark Egg (Mermaid’s Purse) Produced By Oviparous Reproduction

Among the oviparous shark species, some sharks provide biological protection for their eggs by enclosing them in a leathery case, known by many children and beachgoers as a Mermaid’s Purse.

For additional protection, these sharks also push these cases into rock crevices, which, at first glance seems dangerous, but is actually safer for the eggs as the tough, leathery exterior can handle much external pressure. This makes it almost impossible for other fish to access or penetrate the eggs’ cases. These cases often wash up on beaches and shores and appear black and elongated.

The eggs are filled with a nutrient-rich yolk, necessary for the development and sustenance of viable shark pups. Other fish eggs that lack this yolk have poorly-developed babies, many of which die before maturing. In contrast, shark pups are hatched strong, healthy, and independent of their mothers. While we don’t know exactly how long it takes between fertilization and hatching, we do know that this period is extended to allow for sufficient maturation. Once hatched, the pups each go their own direction and will begin their life of hunting, mating and (in some cases) migrating. In other words, these sharks will enter the rat (or shark) race we call life. 

Well known oviparous shark species include the Horn Shark, Port Jackson Shark, Zebra Shark and Bullhead Shark.

A Horn Shark Is Oviparous

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