No, this is not a strange sea pebble. And no, this is not a drill that fell off the installation. You will be surprised, but what you see is an egg. And you will be even more surprised when you find out that the egg is a shark egg!
You may be indignant: “But how? From school we were told that sharks are viviparous.” Indeed, most sharks are either viviparous or ovoviviparous. And only 30% of these waterfowl predators turned into laying hens.
These eggs can be different. And spiral-shaped, and in the form of an anchor, and with all kinds of processes - in short, the imagination of sharks in this matter is truly limitless. They stuffed their children into such strange capsules not because of their design quirks. All sharks have one thing in common - defenselessness.
Shark eggs take a long time to develop - 5-7 months. And all this time, like caviar, they are an easy snack for predators of all stripes. But it’s not only marine life that threatens sharks, but also the sea itself. Currents and waves can easily carry an egg ashore. Therefore, each of the structures serves its own purposes.
For example, the spiral-shaped egg of a horned shark, covered with a cornea, perfectly protects the fetus from meat-eaters. And the numerous threads on the cat shark egg help the fetus to anchor itself in the ground so that it does not get carried ashore. And some, for example, polar sharks, take bait. They give birth to 500 eggs at once, of which only 10 are fertilized.
Well, now you know that the chicken and the shark have a little more in common than might seem at first glance.
