In an obscure geological valley at the very northern tip of Greenland’s large ice sheet, investigators have uncovered scientifically derived evidence of the existence of a lush, ancient ecosystem that was functioning over 2 million years ago. The clues to this ecosystem come from the oldest DNA ever recovered, bits and pieces of genetic material, carefully and tediously extracted from buried sediments representing more than 100 kinds of animals and plants. The investigators painstakingly extracted and “sequenced” the DNA strands and compared them to libraries of existing DNA “reads” from living species today.
This is an incredibly impressive example of the power of environmental DNA (eDNA), as it is genetic material collected from the ambient environment and not individual organisms. The investigative team aimed to collect hundreds of samples from different locations within the ancient valley and reconstruct what this ecosystem looked like before the ice age. They found many different types of conifers, including poplars, thujas, and species like black geese and horseshoe crabs, that are now common further south of Greenland, but most of which are no longer found in the Arctic at all.
There are many reasons that I believe this discovery is important, not the least of which is that it may give scientists clues as to how some species were able to adapt to climate change in the past and give us some insight into climate change and evolution as we advance. It may also turn the time-honored discipline of paleontology on its head by driving it from its almost all fieldwork mode into the molecular biology laboratory.
The DNA/RNA biochemical process plays a very important role within the nucleus of each cell which defines the existence and evolutionary success of living plants and animals on the planet. The article which I selected from “Nature” discussed above, really emphasizes importance of these chemical structures regardless of whether we are investigating the past, looking into possible future biological scenarios, or looking to “improve”, correct or modify existing biological systems. Understanding both the future and historic past of the biology of the planet is no longer simply relegated to the desktop microscope, but more appropriately is a function of understanding the complex biochemical reactions at the molecular level, not just the cellular level. The extraction of biological (environmental DNA) material from historic sediments thousands of years old underscores the important changes taking place in this exciting new field and emphasized to me that the study of DNA/RNA biochemistry is very relevant to understanding all living systems, past, present and likely into the future.