Going back in time to the Devonian period, the most catastrophic era marked by a series of mass extinctions, scientists have identified a surprisingly unexpected culprit that still exists on Earth today.
According to Sci-News, the unexpected monster is none other than plants, specifically their roots. Using a series of fossil and geological records, a team of scientists led by Professor Gabriel Filippelli from the Department of Earth Sciences at Indiana University (USA) pointed out that the evolution of plant roots has repeatedly caused the planet to become inhospitable.
By extracting ancient sediments from several lakes in Greenland, northern Scotland, and Orkney, the authors discovered increased levels of nutritional phosphorus at five different locations during the development and expansion of plant life in the Devonian period (419 to 358 million years ago).
Plants caused 70% of life extinction during the Devonian period – (Photo: Eduard Riou / Rursus).
According to the study published in the Geological Society of America Bulletin, in two instances, the increase in phosphorus corresponded with two extinction events in the Devonian period. Additionally, these events were linked to climate cycles, specifically wet and dry periods.
This nutritional phosphorus was supplied to the oceans, stimulating the growth of local plant life, primarily algae.
This situation is quite similar to the widespread algal blooms caused by nutrient-rich waste from human activities, which are alarming occurrences around the world.
Excessive algae growth depletes oxygen in the water, turning surrounding areas into dead zones. On a larger scale during the Devonian period, along with the fact that life forms of that time still favored the oceans as their habitat, this led to the extinction of 70% of life during six catastrophic mass extinction events of this era.
“New insights into the catastrophic outcomes of natural events in the ancient world may serve as a warning about similar conditions arising from human activities today,” Professor Filippelli cautioned.
