Ever since I was a little kid and saw Jaws for the first time, I’ve been in awe and fear of sharks. They are so fascinating and full of mystery. After watching Shark Week this year I’ve come to realize that the people who spend their entire lives studying these magnificent and terrifying creatures still have so much to learn about them.
While I’m certainly no expert, I learned something about sharks that is so supremely weird. I thought all sharks gave birth to live pups, AKA baby sharks, but when my husband and I paid a visit to the Monterey Bay Aquarium this year we were both taken by surprise when a volunteer pointed out a shark egg, with a little baby shark inside! Sharks lay eggs? That is so bizarre, but, it gets even better.
We learned that sharks can have their babies in three different ways:
- Live Birth called viviparity, similar to how mammals give birth. This can be especially dangerous for the pup since its father may try to eat it!
- Hatching from an egg called oviparity. The eggcase is tough and the shark sometimes lays them in crevices so predators like seals or other sharks can’t get at them. After the shark vacates the egg case, the empty shell is often referred to as a mermaid’s purse. I can’t help but love something so mythological.
- A combination of egg and live birth called ovoviviparity. Here is where it gets weird and kind of brutal. In some ovoviviparous sharks, the siblings will eat each other! As they grow teeth they turn on the other sharks in the womb to make more room until only one is reigning as victor.
It doesn’t seem to matter whether the female shark has a live birth, lays eggs, or uses a combination of egg and live birth, the amazing thing about the female is that there can be one to five males who fathered the pups. Some shark species can give birth from four to twenty pups.
Clearly there is so much to learn from these outstanding sea creatures.
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