I have always been fascinated by sharks. I must have read the shark Zoobooks at least 100 times as a young’n, and when we would visit family in Hawaii, I would sit and stare with my mouth wide open staring at the sharks at the local aquariums and their massive jagged jaws. The sleek cold beauty of a shark is simply unmatched in nature. Due to the ridiculous excitement over Discovery Channel’s Shark Week every year, I don’t think I am the only one with an affinity for these aquatic dinosaurs. As a result, I think we are all fairly well educated on the crazy biological developments in sharks that make them the ultimate seafaring predator. However, I recently came across one fact that makes sharks even more badass – baby sharks battle it out in the womb to be the chosen one.
In some species of sharks, notably tiger sharks (pictured below), unborn baby sharks eat their siblings in the womb in order to survive. Initially, tiger sharks may have as many as 75 little ones swimming around inside of them. However, as they develop and food becomes more scarce, they do what they have to do to survive. By the time the mother is ready to give birth, often times there is one baby left, maybe two.
This is just… the pinnacle of Darwinianism; the Hunger Games and Lord of the Flies on steroids; the ultimate expression of survival of the fittest. The shark who develops fastest will be most able to pick off its siblings, and therefore will grow at an even more rapid rate than the rest of its survival-oriented siblings, thus becoming the top dog and literally coming out of the womb with a killer instinct. No wonder Tiger Sharks are such killing machines.
To protect against this phenomenon and ensure that more than one shark pup is born, some sharks have developed oviducts – basically ovarian compartments to keep babies separated as they develop. To make up for the lack of sibling fodder, the mother periodically sends eggs down the hatch for the shark pups to munch on. In these sharks, the pups can grow to be up to around 40 inches (Over 3 feet long). Some sharks have as many as 8 or 9 of these compartments, meaning that they could be giving birth to nearly 30 feet worth of babies when the time comes.
It is all absolutely mind boggling. I need to stop before I get carried away with my love and fascination with sharks and end up writing the seminal treatise on shark pregnancy. If you have heard of any other crazy shark facts, or just unique and interesting animal facts in general, we would love to hear about them. Thanks!