Because we are one of a kind ever-shrinking attention spansIt can be difficult to understand how long life has existed on Earth. However, try to understand this: Scientists have uncovered fragments of DNA dating back 1 million years.
Found under the floor of the Scotia Sea in the north of Antarctica, these bits of organic matter can be invaluable in determining the history of the area – mapping what lived in the ocean and over what time periods.
technically called GreyDNA – for sedimentary ancient DNA – recovered samples are likely to be useful in ongoing efforts to understand how. climate change may affect Antarctica in the future.
“This is the oldest authenticated sea to date. GreyDNA gives says marine ecologist Linda Armbrecht From the University of Tasmania in Australia, Dr.
GreyDNA is found in many environments, including terrestrial caves and semi arctic permafrostwho has given GreyDNA dates back 400,000 and 650,000 years, respectively.
Cold temperatures, low oxygen, and lack of UV radiation affect polar marine environments such as the Scotia Sea. GreyThe DNA will remain intact, just waiting for us to find it.
The recovered DNA was extracted from the ocean floor in 2019 and went through an extensive contamination control process to ensure the age markers embedded in the material were accurate.
The team discovered diatoms (single-celled organisms) dating back 540,000 years, among other findings. All of this helps inform our overview of how this part of the world has evolved over vast periods of time.
The team was able to link the abundance of diatoms to warmer periods – the last of which was about 14,500 years ago in the Scotia Sea. This has led to an increase in overall marine life activity in the Antarctic region.
“This is an interesting and important change associated with a worldwide and rapid rise in sea levels and massive ice loss in Antarctica due to natural warming.” geologist Michael Weber says from the University of Bonn in Germany.
This last study is GreyDNA techniques can help reconstruct ecosystems over hundreds of thousands of years, giving us a whole new level of understanding of how the oceans are changing.
Scientists are constantly improving at removing these ancient DNA fragments from the ground and removing the ‘noise’ and interference left by all the modern DNA that has since existed to gain an authentic glimpse into the past.
Learning more about past climate changes and how the ocean ecosystem has responded means more accurate models and predictions of what might happen next around the South Pole.
“Antarctica is one of the most vulnerable regions on Earth to climate change, and it is a matter of urgency to examine the past and present responses of this polar marine ecosystem to environmental change,” the researchers write. published article.
Research published Nature Communication.
