The fossil pictured below is of a trilobite, It is said that these creatures, as a form of life, survived in various species, from more than 500 million years ago, until about 250 million years ago. This means that the Trilobites survived and persisted through several geologic periods, even having some species survive mass extinction events along the way. This is remarkable, even incredible persistence for a life form.
A fossil Trilobite from Morocco (purchased in a rock store in Moab, Utah).
The current state of scientific knowledge, based on the fossil record, informs us that there were 5 mass extinction events (where more than 75 per cent of all species went extinct). These are known as End-Ordivician, End-Devonian, End-Permian, End-Triassic, and End-Cretaceous as these type events have marked the end of the respective geologic ages.
What are the causes of such mass extinctions? They say that rapid or severe climate change is usually the culprit along with acidification of the oceans. Extreme volcanic activity and an ice age are claimed as the causes of such severe climate changes that led to some of these past mass extinctions. And, we all have heard of the asteroid or large meteor impact about 65 million years ago that caused the most recent mass extinction of life forms on Earth. Some years back, I had read that one of the older mass extinctions, End-Devonian, may have been caused by interstellar dust or radiation in an area of the galaxy that the Sun and its planets had passed through. The Sun does move around the galaxy over a long period of time. (Do the spiral arms of the galaxy actually move?) But, we do not now see that possible cause listed for any mass extinctions.
Some writers are postulating that we are now in a sixth mass extinction event or process. We cannot deny that animal habitat is being rapidly lost through the expanding human population in the past one hundred years. As well, environmental pollution is also taking its toll on various species of life. And, pollution is not merely chemical pollution. Consider the coming 5G satellite network that is to go “online” or is to be energized in the coming months. Who can say what harm to various life forms (including insects and plants) will occur by this 24/7/365 bombardment from the skies by near microwave length electromagnetic waves? And, it may be heresy to think this, but is this 5G technology truly necessary? Or, is it an example of man’s vanity and greed?
When thinking of man’s future, we may rightly wonder if man will survive more than a brief span of time. Is man to be the cause of this 6th mass extinction event? Will man’s time on the planet be indicated by a very thin line in the rock strata of the Earth of the future? When thinking of man’s possible future, we seem to only have questions, and no answers. Why cannot man learn to live more in harmony with nature, and thus not threaten needlessly all other life on the planet, and even his own future as a living species?
For a look at the geologic time scale with its eras and periods, see this link:
For a brief look at what is known or thought to be known about previous mass extinction events, you can read this article:
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