While diving deep in the Caribbean, researchers made a rare sighting. They filmed a shark embryo and its egg, attached to corals.
For 22 days in 2018, researchers from the National Oceanic and Atmospheric Administration (United States) plunged into the around Puerto Rico and the US Virgin Islands. They brought back some treasures. Pictures, for example, of a shark in its egg. And that deserves some explanation.
First of all, it is good to remember that amongthere are . Their embryos develop in the mother, thanks to the nutrient reserves of the . They are mostly midwater sharks. But there are also ovoviviparous. Their embryos develop into an egg that remains in the from the female until hatching. Finally, there are oviparous. These lay eggs in the waters. They live more often in the depths.
There are approximately 400 species of sharks, about 40% lay eggs.
When the eggs are ugly, they are in a protective egg case with tendrils which allows it to attach to substrate such as coral. pic.twitter.com/UlzGF4plbi
— Science girl (@gunsnrosesgirl3) August 18, 2020
A shark embryo and its egg
And it is precisely the egg of one of the latter that the researchers had the chance to observe during a memorable dive at a depth of more than 250 meters. An exceptional observation on this day in November 2018, which reveals the embryo of a shark, trapped with its egg in a kind of resistant shell. These shells are usually attached by long strands to invertebrates or algae – here to corals – on the sea floor. It is in theinside the egg that the embryo will find all the necessary for its development.
After a few months, because at the bottom of the oceans, life takes its time, the little shark – a cat shark, according to the researchers – will finally be ready to come out of its egg. He will then have to manage without the help of his mother. To survive, his only chance will be to.