A new study from Denmark has delved into the hypothesis surrounding the biological explosion that occurred 467 million years ago and the connection to the collision between two asteroids.
The Ordovician Biological Explosion 467 million years ago marks the largest increase in biodiversity ever recorded in Earth’s history. Geological and fossil records reveal it is closely related to a cooling period on Earth, a glacial epoch caused by extraterrestrial factors.
An asteroid collision could release countless cosmic dust particles – (Photo: NASA/JPL-Caltech).
Specifically, this event involved a collision between a massive asteroid, which released a large amount of cosmic dust enveloping Earth, blocking sunlight and causing colder weather. A study published in 2019 suggested that two large asteroids from the asteroid belt between Mars and Jupiter were responsible, with the collision being so significant that dust spread far throughout the Solar System.
In the new study, a research team led by geologist Jan Audun Rasmussen from the Mors Museum (Denmark) and paleontologist Nicolas Thibault from the University of Copenhagen (Denmark) found that the asteroid collision indeed occurred and sent meteorites crashing to Earth for a time, but it was not the trigger for the biological explosion.
Through a thorough analysis of fossils from sedimentary seabed at Steinsodden (Norway), preserved in limestone layers, they determined that the cooling of Earth and the biological explosion originated hundreds of thousands of years before the asteroid collision. The onset of the glacial epoch was 469.2 million years ago, and the climate continued to cool for another 200,000 years, leading to the formation of ice in Antarctica (which was once a lush continent in the past).
According to Science Alert, the authors suggest that the cause of this glacial epoch was a change in Earth’s orbit—its elliptical shape becoming slightly elongated—combined with a change in axial tilt, a phenomenon that occurs frequently.
However, this does not mean that extraterrestrial dust had no impact on Earth. Dr. Rasmussen asserts that the dust from the ancient collision not only did not trigger the biological explosion but also acted as a brake on the evolution of species.
The origins of the bizarre and unique life forms from this period remain a puzzle that requires further investigation.
