December 19, 2022

Noa Essner

10th Grade

Ramaz Upper School

Beneath the Scotia Sea Floor in the Antarctic Ocean, scientists unintentionally discovered remnants of DNA from microorganisms. This DNA, known scientifically as sedimentary ancient DNA, due to its being found among the accumulation near the sea floor, is estimated to be roughly one million years old. Though the DNA found in Antarctica was discovered back in 2019 as part of a research project prompted by the International Ocean Discovery Program, it wasn’t until a few weeks ago that scientists concluded that this strange DNA is much older than the 650,000-year-old sedaDNA (“Sedimentary Ancient DNA”) found in the frozen Antarctic, making it one of the world’s oldest found DNA samples to date. 

Antarctica as a geographic location is a remarkable place to conduct scientific research, as its oceans influence some of the other world’s oceans, and its contents aid scientists in learning about the Earth’s past climates. Thus, the reason for collecting samples of the Antarctic Ocean floor was to learn more about pollution and the impacts that dumping waste into oceans has on the bodies of waters’ healths. This is important because the more research conducted on ocean sea floors, the better of a grasp scientists will have on how oceans and their ecosystems are responding to climate change and therefore what measures need to be taken to protect them. 

Scientists have narrowed down the possibilities of what species these DNA fragments belonged to the Domain of Eukarya, a scientific classification rank that includes species whose cells contain membrane-bound organelles. In other words, the bacteria found can not belong to fungi or bacteria. Most of this DNA, however, was identified as belonging to diatoms, a species of phytoplankton, and are quintessential components of aquatic food webs, as they provide their stability. By analyzing the DNA fragments as well as attempting to figure out what species they belong to, scientists have hypothesized that as Earth underwent a period of natural increase in temperatures roughly 54,000 years ago, the diatom population simultaneously increased significantly in Antarctica. This discovery gives scientists new insight as to what Antarctica might have looked like thousands of years ago, both in terms of temperature and its species.