The Icelandic walrus lived on the island of Iceland for thousands of years but died out shortly after the arrival of the first Norwegians around 870 AD. Researchers believe it was no accident: these animals were hunted and above all the ivory of their horns was marketed. Now a new study, published in Molecular Biology and Evolution, provides us with new information about it.
Icelandic, Danish and Dutch researchers have in fact analyzed the ancient DNA of some collections of bones preserved in the museum of Icelandic natural history and have performed carbon 14 dating of some remains of walruses. The study confirms first of all that this animal lived in Iceland for thousands of years and disappeared with the arrival of the first groups of Norwegians.
The researchers also compared the DNA of these walruses with contemporary walruses and confirmed that it was a single genetic progeny distinct from all other populations of both contemporary and historical walruses. According to Morten Tange Olsen, a researcher at the University of Copenhagen and one of the authors of the study, this research shows one of the first examples of extinction of a marine animal following the arrival of groups of human beings and following the exploitation carried out by the latter.
The ivory of walruses was in fact considered a luxury commodity and was in great demand both during the Viking era and during the Middle Ages in the rest of Europe. There are numerous documents describing carefully decorated walrus tusks that were marketed from Europe to the Middle East and on to India.
“More than 1000 years ago, commercial hunting, economic incentives and commercial networks were of sufficient size and intensity to cause significant and irreversible ecological impacts on the marine environment, potentially exacerbated by a hot climate and volcanism,” says Xénia Keighley, researcher at the GLOBE Institute in Copenhagen and the Arctic Centre in Groningen and principal author of the research.