Earth’s Environment has experienced major changes over the time. Global Cooling, global warming, volcanic eruptions, acid rains, carbon emissions all these changes have lead to mass extinction events. Our planet has experienced five mass extinctions in the past due to the environmental changes. Here’s a glimpse through the extinction phase and what might be the future of our planet.
Ordovician mass extinction (occurred approximately 443 million years ago):
The Earth was mostly covered in water at that point of time; most of the creatures at that stage either lived in the oceans or crawled around the oceans bodies. The newly formed volcanic rocks that were flooded into the ocean by other water bodies and wind may have reacted and absorbed the Carbon Di-oxide (CO2) in the atmosphere dropping the atmospheric and oceanic temperature drastically. The reduced temperature caused water to lock down and form ice. The shallow seas drained out and the water level of the oceans dropped; thus more than 50% of the existing life at that stage faced extinction making it the third largest extinction in the history of the planet.
Millions of years later the oceans began to slowly repopulate with aquatic life and life on land began to flourish with plants, insects and other crawling animals.
Late Devonian mass extinction (occurred approximately 370 million years ago):
The newly colonised terrestrial plants started absorbing the Carbon Di-oxide (CO2) at a rate much higher than its formation by the insects and other life forms; thus causing in global cooling effect. The nearby soil loosened and the nutrients of the soil washed away into the oceans and layers of algae formed on the surface. The algae started absorbing Oxygen (O2) radically thus most of the species were eventually chocked to death.
A few million years later some of the species of the ocean started adapting and developed feet and fins (later came to be known as amphibians).
Permian extinction (occurred approximately 252 million years ago):
Volcanic activities were at it peak during this era; the volcanic eruptions liberated billion of tonnes of gases into the atmosphere which destroyed Earth’s Ozone layer leading to acid rains which in turn destroyed most of the Planets terrestrial life. The temperature of started rising very quickly making it difficult for life to adapt to this change. This is the greatest known extinction in the history of our planet.
Amphibians that developed feet started evolving and adapting to the environment on land and once life was restored to the planet. Life has only a few years to evolve during Triassic stage and yet another catastrophe strikes the planet.
Triassic extinction (occurred approximately 200 million years ago):
Earths core started experiencing changes at this stage. A huge volcanic rift caused the landmass to split forming some of the named continents that exist today. The sudden climatic change and volcanic activities liberated great amounts of Carbon Di-Oxide into the atmosphere increasing the temperature of the atmosphere and once again making it difficult for life to adapt to this change and causing yet another mass extinction that claimed around 76% of planets species.
The few species (later to be known as Dinosaurs) that survived the Triassic extinction began to evolve and turn out to be one of the largest and some of the most ferocious species know to our planet. Some of the species (known as Tyrannosaurus) began dominating life the planet and were now on top of the food chain.
Cretaceous extinction (occurred approximately 65 million years ago):
Earth was hit by asteroid / comet the impact released billions of tonnes of dust into our environment forming dust clouds that blocked out sunlight. At the very end of this phase a major volcanic activity again hit the planet releasing high amount of Carbon Di-oxide and causing acid rains which in turn eradicated the rest of the surviving species of out planet. The Cretaceous extinction claimed almost 81% of the species of our planet.
At the beginning of modern age mammals started evolving which later lead to all the known species of our existing age. Now, humans dominate the planet and we have maximised the use of all available resources to the best of our knowledge; and are trying to find new ways to exploit the resources even further.
Extinction of Man Kind
Are we moving towards the next phase of extinctions?
We are consuming natural resources at an alarming rate. If past is any indication of the future; every time the planet undergoes a major change the most dominant species of the planet are wiped away to give a chance to lesser dominant species to evolve and co-exist peacefully.
Environmental changes in the past have occurred over a period of millions of years but the rate at which we are polluting our planet and exhausting our natural resources.We have covered a quarter of that within the past five decades. We are already experiencing major climatic changes all over the world. Recent Earthquakes and Volcanic activities are Earth’s way of warning us that it has suffered enough. If we do not take action soon; Humans will be wiped from the face of the Earth.
The question we need to ask ourselves is
Will this be the fall of Man Kind?
Will the most advanced species of the planet lead to its own extinction?
Will we learn from the past and take action to build a better future.
UCMP – University of California Museum of Palaeontology