THERE are many things that Sharks are notorious for. We know they hunt their food, have one of the deadliest jaws in the world and have the scariest horror movie based on real-life animals.
But there's one thing that has even scientists puzzled about the apex predator of the water world - how exactly do they procreate?
Is it true that shark's lay eggs like other fish?
Verdict:
PARTIALLY TRUE
With hundreds of different species of sharks in the oceans (at least the ones we've discovered), it’s no surprise that there’s a diversity in its reproduction methods.
Decades of studies showed that about 70% of sharks are viviparous, meaning they give birth to live young, while the remaining 30% are oviparous, meaning well, they lay eggs!
Well, some sharks lay eggs, but most have eggs inside their body that they incubate until they’re hatched. They then birth the hatched young into the ocean.
An egg case or egg capsule is the casing surrounding oviparous sharks' eggs. Each egg contains a baby shark (do do do do do do) and a yolk sac - its first meal, much like a chicken's egg.
But before you imagine them looking like your breakfast or something from Jurassic Park, lets just say that saying the shark egg cases look extraordinary is a bit of an understatement.
Unlike chicken eggs, shark eggs are encased in a leathery, watertight shell designed to keep baby in and predators out.
Some catsharks lay eggs that are purse-shaped with long tendrils at the corners. The tendrils are meant to anchor them to structures on the sea floor.
These are known as "mermaid's purses."
Some species have egg cases have long, horn-like appendages on each side, and these are known as "devil's purses."
Bullhead shark egg cases are shaped like an auger with two spiral flanges. This allows the egg cases to become wedged in the crevices of rocky sea floors, where the eggs are protected from predators.
Bamboo sharks and the zebra shark lay eggs on the sea floor so their egg cases are oval and covered with adhesive fibres that secure them to the bottom.
No matter how a shark is born or hatched, it is born independent. A shark baby is known as a pup, and those that are born swim away from their mother as fast as they can to avoid being eaten.
They also certainly don't cling to their parents for 18 years before going off to live on their own, unlike some other 'dominant' species on the land.
References:
1. https://www.livescience.com/62325-shark-egg-embryo-gif.html
2. https://a-z-animals.com/blog/do-sharks-lay-eggs-the-answer-will-surprise-you/
3. https://www.americanoceans.org/facts/do-sharks-lay-eggs-or-give-birth/
