May 11, 2021

This is the explanation to the mystery of the marine gelatinous globes


Huge gelatinous spheres from the NE Atlantic Ocean (Norway, Sweden and England) attributed to squid egg mass.

Huge gelatinous spheres from the NE Atlantic Ocean (Norway, Sweden and England) attributed to squid egg mass.
EP

A citizen science campaign and DNA analysis has revealed the nature of mysterious marine gelatinous spheres that There are a hundred sightings between Norway and the Mediterranean since 1985.

Several years ago divers exploring the western coast of Norway found an object they couldn’t explain: a huge, jelly-like orb, over a meter wide, floated in place midway between the seafloor and the surface. A dark streak ran through the center of the orb, but the object was otherwise translucent and featureless.

Other mysterious gelatinous masses have always eluded classification. Now, researchers have finally identified the spots as the Rarely seen egg sacs of a common squid called Illex coindetii.

According to a new study, published in Scientific Reports, each drop can contain hundreds of thousands of tiny squid eggs, encased in a slowly disintegrating bubble of mucus. Surprisingly, although scientists have known about I. coindetii for more than 180 years and have observed the species throughout the Mediterranean and both sides of the Atlantic, this is the first time they have identified squid egg sacs in the wildthe researchers wrote.

“We were also able to see what’s inside the real sphere, showing squid embryos at four different stages,” the study’s lead author told LiveScience.com, Halldis Ringvold, manager of the marine zoology organization Sea Snack Norway. “Also, we were able to follow how the sphere actually changes in consistency, from firm and transparent to ruptured and opaque, as the embryos develop.”

I. coindetii belongs to a common group of squids called Ommastrephidae. During reproduction, the females of this group produce large egg spheres, or egg masses.made from their own mucus to keep their embryos floating and safe from predators, Ringvold said. However, sightings of these stands are rare and masses of some species have never been seen before.

Ringvold and his colleagues launched a citizen science campaign that encouraged divers to collect small tissue samples of any stain they found in the waters near Norway. In 2019, divers obtained tissue samples from four separate spots, which they collected in small plastic bottles and stored in home refrigerators (tissue collection did not appear to harm the egg masses in any way, according to the study).

The samples included both the sticky body of the spots and embryos at different stages of development. A DNA analysis of the tissues confirmed that all four spots contained squid I. coindetiithe researchers wrote.

So, mystery solved? Partially. Without taking tissue samples from each sphere, the researchers cannot be sure that the almost 100 spots observed belong to the same speciesthe team wrote. However, since all of these spots were very similar in shape and size, it is probable that “many of them” were made by I. coindetiithe team concluded.

As for the strange, dark streak that runs through many of the spheres? According to the researchers, This could be due to the release of ink when the eggs are fertilized.

“The spheres with or without ink may be the result of the spheres being at different stages of maturity, where the spheres with ink are newly generated,” the researchers wrote in their study. “After a while, when the embryos start to develop, The entire sphere, including the line, will begin to disintegrate. “

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