Scientists have discovered a new faunistic border in the Arctic Ocean, with two different forms of meduses to live fully separated.
A new published in the Deep Sea Research Part I revealed a surprising faunistic border in the depths of the Arctic Ocean, which separates two distinct forms of the same kind of jellyfish.
In the abyssal depths beyond the 1000 meters – the so -called “midnight zone” Botrynema brucei ellinorae They appear in two different morphotypes: some have a distinct button -shaped structure on their hoods, while others do not.
Despite physical differences, both morphotypes belong to the same genetic lineage, according to the genetic analysis led by Marine Biologist Javier Montenegro of the University of Western Australia, and his team. The study reveals that while button -down nasks are globally distributed, the variety without button There is only northern parallel 47, In the Arctic and Subarsal regions, reports the.
“There have never been a button -free specimens south of the North Atlantic Deriva region,” said Montenegro. This oceanic area extends from the large banks of the New Terra to the northwest of Europe and seems to act as a biogeographic frontieralthough no physical structure divides the regions.
These faunal borders – invisible lines that separate ecosystems although there is no apparent physical obstruction – are rare and difficult to detect, especially in deep water. Comparable lines on land include the Wallace linewhich distinguishes the distinct animal life from Asia and Australlasses. In the hostile depths of the ocean, these divisions are even more elusive due to extreme conditions and the difficulty of exploration.
To investigate the distribution of the meduses, the researchers used data from historical records and new collections and employed research ships and images captured by remotely operated underwater vehicles (ROVs). The results showed a clear geographical segregation Between the two forms.
The reason behind this biological division is still unknown, but the researchers propose that the form with buttons can offer a selective advantageperhaps related to predators escape, which allows these jellyfish to thrive south, while another form remains confined to the colder waters of the north.
