New research points toward the initial culprit in the global warming issue. That means that animals that lived over 500 million years ago, and started evolving in the ocean, led to consuming the oxygen in the atmosphere and creating more carbon dioxide.
Those animals broke down organic material on the seafloor and raised the carbon dioxide levels, causing the first stage of global warming.
Then, over the next 100 million years, life in the ocean became a lot harsher, because of the level of oxygen was getting too low, followed by mass extinction events.
An international team of researchers has published their findings in Nature Communications. Authors from the Universities of Exeter, Leeds, and Antwerp, and the Vrije Universiteit Brussel contributed to the discoveries.
Professor Tim Lenton, from the University of Exeter, explains how it all started:
“Like worms in a garden, tiny creatures on the seabed disturb, mix and recycle dead organic material—a process known as bioturbation. Because the effect of animals burrowing is so big, you would expect to see big changes in the environment when the whole ocean floor changes from an undisturbed state to a bioturbated state.”
Professor Filip Meysman, from the University of Antwerp, added that in their study, they saw that the oxygen levels in the ocean started to decrease around 520 million years ago:
“But evidence from the rock record showed sediment was only a little disturbed.” Professor Simon Poulton, from the University of Leeds, continues explaining that the evidence only meant that “the animals living in the seafloor at that time were not very active,” and they couldn’t move deep into the seabed:
“At first sight, these two observations did not seem to add up.”
Then, the lead author of the study, Dr. Sebastiaan van de Velde (Vrije Universiteit, Brussel), explained:
“This meant that the first bioturbators had a massive impact.”
Researchers found out the “missing piece of the puzzle”, which helped them create a mathematical model of Earth in that period and looked at the changes that these early life forms have caused on Earth.
Dr. Benjamin Mills (the University of Leeds), led part of the research that used the mathematical model of Earth, explaining that the findings from the model were surprising:
“The evolution of these small animals did indeed decrease the oxygen in the ocean and atmosphere, but also increased atmospheric carbon dioxide levels to such an extent that it caused a global warming event.”
Professor Lenton, director of Global Systems Institute, Exeter, concludes that the way early animals changed the world is a parallel to what we do now:
“We are creating a hotter world with expanding ocean anoxia (oxygen deficiency) which is bad for us and a lot of other creatures we share the planet with.”
Rex Austinwas born and raised in Thunder Bay Ontario on the shores of Lake Superior. Apart from running his own podcast (Ice Fishing And Other “Cool” Things), he spends his time canoeing and backpacking in Northern Ontario.. As a journalist Rex has published stories for Global News (Thunder Bay) we well as Buzz Feed and Joystiq. As a contributor to Great Lakes Ledger, Rex most covers science and health stories. Contact Rexhere