Ovoviviparous: Ovoviviparous shark eggs hatch inside of the uterus. However, the pups are not feed a placenta and will eat unfertilized eggs and other pup fetuses to survive. Great White Sharks, Thresher Sharks, Sawsharks, Mako Sharks, Tiger Sharks, Nurse Sharks, Greenland Sharks, Gummy Sharks, and Cookiecutter Sharks are all ovoviviparous.

Placental viviparity is a type of viviparity that is seen in some shark species. In this type of viviparity, the embryo is nourished by a placenta-like structure that develops within the mother’s uterus.Skate, chimaera and some shark species produce eggs encased in a tough 'leathery' eggcase. A female may spend a long time laying her eggs, ensuring they’re securely fixed in a safe place. It can take between 6-9 months before they’re ready to hatch. Tonic immobility is a reflex that causes a temporary state of inactivity in an animal. Similar to hypnosis. It occurs in a variety of different species, including many sharks and rays...

Sharks are like Tiger Sharks, Nurse Sharks, Greenland Sharks, etc. are actually ovoviviparous. This means that the eggs hatch inside the mother’s uterus and the pups soon start to feed on the other unfertilized eggs and other pup fetuses to survive. These all happen inside her body and the pups also develop inside. They will come out after their partial development is over. When they do reproduce, the pregnancies last for a long time, and few pups are born. For most sharks, gestation lasts between 9-12 months, but for some species, gestation can last for up to 31 months. Sharks have a range of adaptations that make them perfectly suited to their environment. It's no wonder they've gained a reputation for being some of the most impressive and formidable predators on the planet! Duffy, C. 1997. Futher Records of the Goblin Shark, Mitsukurina owstoni (Lamniformes: Mitsukurinidae), from New Zealand. New Zealand Journal of Zoology, 24: 167-171.

Bull Shark Facts

Up to two-thirds of the total weight of a shark’s brain is dedicated to smell. They use their smell sense organs to detect their potential mate and know if they are ready to mate. Depending on the species of shark, they may produce as few as two pups with each reproduction. The largest number of pups produced can be attributed to the Blue Shark which can have up to 135 sharks. That may seem like a lot, but even that isn’t enough. In sharks the male and female individuals are separate and they only mate (sexual intercourse) during their breeding season at their breeding place. When they are ready to mate, the male will hold onto the female. Many female sharks have been noticed with bite marks on their bodies because of this. Some have even been seen missing part of their dorsal fin. Like all sharks, goblin sharks probably hunt using their senses of smell, sight, sound and the electrical sensing organs called ampullae of Lorenzini. Due to the depth at which they live, eyesight is probably less useful than other senses. The snout (which is abnormally large in Mitsukurina owstoni) houses the ampullae of Lorenzini which are attuned to catching otherwise undetectable prey in dark waters or on the bottom.

Once fertilization occurs, the female will carry the fertilized eggs until they are ready to hatch. Ledgerwood said none of the Dunedin old-timers had ever heard of, or witnessed such an event, and many could make no sense of what the ageing fisherman had seen.Fin of Great white shark breaking surface of sea, side view. Photograph: Martin Barraud/Getty Images Goblin sharks seem to live in the mid and deep-water zones of outer continental shelves and slopes. ( Martin, 1999) Unlike oviparity where the egg cases are tough, ovoviviparity produced eggs have a thin membrane that is easy to break out of. When the young is fully developed, the mother will then give birth to the pups. Ovoviviparous sharks will generally produce between 1 and 8 pups. There is only one other incidental, distance observation potentially describing this mating phenomenon in all of the scientific literature,” says Crawford. Sharks are fascinating creatures that have been around for millions of years. One of the most interesting aspects of their life cycle is their gestation and birth process. Gestation Period