The process by which sharks change from eggs to life (12).
The history of sharks even dates back to the time of dinosaurs, but they still need to work hard to create a better living environment for future generations. Every spring, thousands of sharks gather in Jervis Bay, Australia, and during the breeding season, they can number in the thousands. No matter where the female shark is, male sharks will follow. In the courtship process of the shark, there is less temptation and more fighting. Eventually, however, they were successfully paired. Male sharks are almost completely unaware of the feeding of the next generation, and all responsibility falls on female sharks. After two weeks, the female sharks begin laying eggs. The roe is about the size of a head and shaped like a corkscrew. In order for the eggs to grow healthily, female sharks need to spend a lot of energy. If they can't find a safe place to hide, their previous efforts will be in vain.
Finally, they found the ideal hiding place, and the eggs turned into this shape that could be safely embedded in the rock. Female sharks will hold their eggs in their mouths until they find the ideal hiding place. Fish eggs need to be hidden for 11 months. There is a species of egg thief here, the crested horn shark, which looks similar to the Port Jackson shark but is the main predator of Port Jackson shark eggs. The egg shell is hard, but the crowned shark bites easily and squeezes the yolk out of it.
The eggs are safely hidden in ravines, avoiding attacks by predators. The female Port Jackson shark has done her job and can leave here in search of food. In the protective shell of the eggs, everything necessary for the growth of the baby shark is ready. From corkscrews inserted into rocks to mermaid handbags hidden on the ocean floor or suspended in seaweed, these eggs come in different shapes and sizes.
Different species of shark eggs vary in size and shape, and each shell has a natural life-support system. The embryos develop slowly in the yolk sac, which provides the young sharks with all the necessary nutrients until they hatch. For some species of sharks, the process takes nearly a year. After a few weeks, the baby shark's eyes, mouth and fins begin to take shape. The yolk sac delivers nutrients to the baby sharks through a vein. At this stage, wavy leaf-like gills stick out from the side of the head to absorb oxygen from the surrounding seawater. The baby shark will repeatedly contract and stretch its body, allowing fresh water to circulate in the eggs. As they grow, camouflage patterns begin to form on their skin, which is important for their later hatching. Now, their gills have entered the body and their teeth have begun to form, but they have no food. The yolk sac has almost been depleted. The moment came to break out of the shell, and under the cover of darkness, the leopard shark emerged from the shell that had protected it for months, by which time it was fully formed, a 20-centimeter-long shark, ready to start self-reliant.