An Irish-based scientist has been involved in a new discovery showing that there is only one species of the enigmatic giant squid worldwide. The subject of mariners tales since ancient times, this huge 10 armed invertebrate can grow to 13 meters and lives at depths of up to 1000 meters under the sea.
Dr Louise Allcock of the Ryan Institute at NUI Galway was a member of an international team, led by the University of Copenhagen, which studied the genetic code of the giant squid, which can weigh over 900 kg.
It is less than a year since the giant squid was first filmed alive in its natural element, at a depth of 630 meters by a submarine near Japan. “The giant squid is extremely rarely seen, except as the remains of animals that have been washed ashore, and placed in the formalin or ethanol collections of museums,” explains Dr Allcock. “For a long time it has remained unclear how many species of giant squid exist. Our mitochondrial DNA data strongly point to the existence of a single species.”
The research was led by PhD student Inger Winkelmann and her supervisor Professor Tom Gilbert, from the Basic Research Centre in GeoGenetics at the Natural History Museum of Denmark, Copenhagen University.
The study, which is published today in the esteemed journal, the Proceedings of the Royal Society B, analyzed DNA from the remains of 43 giant squid collected from all over the world. The results show, that the animal is genetically nearly identical all over the planet, and shows no evidence of living in geographically structured populations.
One possible explanation for this is that although evidence suggests the adults remain in relatively restricted geographic regions, the young that live on the ocean’s surfaces must drift in the currents globally. Once they reach a large enough size to survive the depths, the authors of the paper believe they dive to the nearest suitable deep waters, and there the cycle begins again.
Scientists have yet to discover how old the creature gets, how quickly they grow and how they might have been affected by climate change in the past.
“These are fascinating creatures, living in one of the planet’s most extreme environments, yet growing to gigantic proportions”, concludes Dr Allcock. “There is still so much we to learn about them, and ultimately about our planet.”