The Great Extinction Events: What Caused Them and What Can We Learn from Them?
Extinction events are a major and well known part of the history of the planet. But, what many don’t know is just how often, and how severe, some of these events have been. What’s more, the causes for some of these extinctions remain elusive even today. This article will take a look at the Great Extinction Events, what caused them and what are some lessons to be learnt from them.
What are the Great Extinction Events?
The ‘Great Extinction Events’ refer to five major mass extinction events, which occurred during the earth’s history. These events have led to the extinction of millions of species and have greatly altered the planet’s ecology. The five ‘Great Extinction Events’ and the dates they occurred are as follows:
• End Ordovician Extinction (440 million years ago)
Late Devonian Extinction (360 million years ago)
Permian Triassic Mass Extinction (252 million years ago)
Triassic Jurassic Extinction (201 million years ago)
Cretaceous Paleogene Extinction (66 million years ago)
What are the Causes of the Great Extinction Events?
The causes of the Great Extinction Events remain a topic of debate and theory today. Different theories have been proposed for each of the five events. Although the causes can vary from event to event, some more general causes have also been suggested.
Volcanic Activity: One of the causes that has been proposed for many of the extinction events has been volcanic activity. The release of huge volumes of ash and gas, due to volcanoes, is believed to have caused the atmosphere to become extremely acidic, which was fatal to many species.
Asteroid Impact: The theory of an asteroid impact causing the Cretaceous Paleogene Extinction event is one of the best known extinction theories. The asteroid, which is believed to have hit the Yucatan Peninsula in Mexico, is thought to have wiped out the dinosaurs and many other species.
Climate Change: On most of the Great Extinction Events, there has been some evidence of drastic climate change or cooling. This shift in climate could have had fatal effects on organisms, as well as the ecosystems in which they lived.
What Can We Learn from the Great Extinction Events?
The Great Extinction Events have proved to be one of the most devastating events in the planet’s history. Such events have highlighted the fragility of the ecosystems in which we live and their susceptibility to environmental disasters. Thus, understanding the causes and the effects of these events can provide us with indispensable knowledge which can help us avoid similar events in the future.
Overall, the Great Extinction Events have caused massive losses in biodiversity and changed the face of the planet’s ecology. Through studying their causes, we can begin to uncover what caused these catastrophic events and what we can do to avoid them in the future. The lessons learnt from the Great Extinction Events can help us to better understand and appreciate the complex relationships between organisms and their environment, as well as the impact of human actions on the planet’s ecology.
