Antarctic octopus DNA holds key to rising sea levels, scientists warn

Scientists have recently turned to an unexpected source of information about Antarctica’s changing environment: an Antarctic octopus species that inhabits the icy waters around the continent. This octopus, known as Turquet’s octopus (Pareledone turqueti), has provided valuable genetic clues about past shifts in Antarctica’s ice sheets, which could help predict future sea level changes as global temperatures rise, according to Earth.com.

Turquet’s octopus, which has been present in Antarctica for around four million years, is unique due to its distinct genetic populations that have developed in isolated regions due to circular sea currents. This cephalopod, measuring about 15 centimeters long and weighing roughly 600 grams, is an excellent indicator of environmental changes because it lays large eggs that require careful tending on the seafloor, making its populations more genetically distinct.

Researchers analyzed DNA from 96 octopus samples collected over three decades, discovering that the species once traveled between the Weddell, Amundsen, and Ross seas, suggesting that large expanses of ice once melted, creating open channels for movement. Genetic evidence points to two key periods when this occurred: around 3-3.5 million years ago during the mid-Pliocene and again between 129,000 and 116,000 years ago during the Last Interglacial period, a time when the planet was about 1.5 degrees Celsius warmer than pre-industrial levels.

This finding is significant as current global temperatures have already risen by 1.2 degrees Celsius, and experts warn that the West Antarctic Ice Sheet (WAIS) may be on the verge of collapse. If the WAIS destabilizes, it could lead to a long-term rise in sea levels by up to 5 meters, potentially reshaping coastlines worldwide.

The study’s results suggest that the tipping point for a WAIS collapse may be closer than previously thought. Scientists are also investigating other factors, such as changes in ocean currents, that could influence how quickly ice sheets melt and contribute to rising sea levels. Additionally, ongoing studies of the Southern Ocean’s changing dynamics, including shrinking sea ice and stronger storms, highlight the broader impacts of warming on global climate systems.

By Vugar Khalilov