Octopus DNA solves scientists’ mystery

Octopus DNA reveals when the rapidly melting West Antarctic ice sheet last collapsed.

A study of octopus DNA may have solved scientists’ mystery about when the rapidly melting West Antarctic ice sheet last collapsed.

The groundbreaking research focused on the genetic history of the Turke’s octopus (Pareledone turqueti), which lives on the Antarctic seafloor.

Tracking populations of this species suggests that the last ice sheet collapse occurred more than 100,000 years ago during a period known as the Last Interglacial, Science magazine writes.

“The DNA of living animals today contains all the information about their ancestors (in) the past, so it’s like a time capsule,” said a researcher on the project.

By sequencing the DNA of 96 Turke octopuses that were collected around the world over the years. The oldest specimens dated back to the 1990s, but once sequenced, their genes provided what was essentially a detailed family tree going back millions of years. The team looked at the genetic information of the Turke octopus, pictured above.

DNA analysis allowed the researchers to understand whether different populations of Turke’s octopuses interbred and at what point this interbreeding occurred.

Today, populations of Türk’s octopus in the Weddell, Amundsen and Ross seas are separated by continent-sized West Antarctic ice shelves and cannot mix.

However, the study found that the last genetic link between these populations existed about 125,000 years ago, during the last interglacial, when global temperatures were similar to today.

This discovery indicates that the West Antarctic Ice Sheet collapsed during this time, an event that would have flooded coastal areas but would have opened up ice-bound areas on the seafloor that octopuses could have occupied, eventually meeting and breeding with members of the West Antarctic Ice Sheet. populations of Türk.