Octopus DNA may hold clue to global warming, study finds
[ad_1]
DNA analysis of an octopus that lives in the Southern Ocean shows that the ice sheet is under threat of destruction. A 1.5℃ increase in the average global temperature may be the driver for this.
In a study published in the scientific journal Science, a group of international scientists concluded that the Earth is now close to this indicator, writes The New York Times.
Scientists note that in the waters around Antarctica there are several separate populations of Turket octopuses (Pareledone turqueti). They live on the seabed and are usually near their “home”.
A few individuals or their eggs may sometimes drift with currents to neighboring groups, but populations in the Ross and Weddell Seas are separated by an impassable ice sheet.
| Octopus Turket. Photo: Dave Barnes/BAS |
However, genetic analysis of octopuses of this species, which live in different places around Antarctica, showed that about 120 thousand years ago, these populations mixed and exchanged DNA.
It was at this time that the Earth had the last interglacial period, which preceded the last ice age. Then the temperature indicators were about the same as now.
According to scientists, changes in DNA would be possible if there was no West Antarctic Ice Sheet and octopuses were able to move freely. However, it is not known whether additional water came from West Antarctica at that time.
Currently, the average global temperature is about 1.2℃ higher than in the pre-industrial period of 1850-1900. During the last interglacial period, it was warmer by about 0.5-1.5℃, but the sea level was also 5-10 meters higher then.
Researchers cannot say for sure whether the current temperatures have already led to the complete destruction of the western ice sheet. However, if this happened, it can melt within 200-2000 years.
It will be recalled that scientists have found out that the reason for the very rapid melting of some glaciers in the Antarctic may be an atypically hot core in the atmosphere.
The rapid melting of the Antarctic ice slows down the movement of deep ocean currents, which can have a catastrophic effect on the climate, in particular causing cooling in Europe.
According to scientists, Antarctica has lost about 7.5 trillion tons of ice in 25 years. Also, global warming has accelerated the rate of melting of the glaciers in Greenland by five times, compared to the situation that was 20 years ago.
Read also: Life will be in danger: scientists simulated the conditions of life on Earth in 250 million years
[ad_2]
Original Source Link
