The long orange strip unfurled from the small roll at the end and then snaked across the entire wall. It changed colour from deep to light orange before morphing into a green strip and finally ending with a tiny four-inch blue coloured block at the end.
I was looking at a timeline representation of the start of life on earth, about three and a half billion years ago, culminating with the appearance of us humans two hundred thousand years back. That blue-coloured block highlighted the minuscule period ( around 0.006% of total ) that we humans have existed on mother earth as compared to all life.
I was at the Smithsonian Museum of Natural History on a recent visit to Washington DC. Though the museum carries the same name as the more well-known American Museum of Natural History in New York, I was finding the format and the presentation refreshingly different.
As I looked at the representation, I was intrigued to see the periods of mass extinction that have taken place in the planet’s living history. There seem to have occurred around five major extinction events since earth cradled life. These were when between fifty to ninety-five percent of all living species died out. I got particularly interested in two such events.
The first was the one that led to the demise of the dinosaurs. I sat watching a video of what might have happened sixty-six million years back when the age of the dinosaurs ended. A large meteor comes hurtling from outer space and hits earth in the Mexican coastal region. The impact kills all life on land and sea for thousands of kilometers all around, its explosive power equivalent to billions of atomic bombs going off at the same time. And as if that is not enough, giant tsunamis and billions of tons of vaporized asteroid and terrestrial debris spew up into the atmosphere, envelop the earth and block out sunlight for years. Photosynthesis all over the world gets seriously impeded and the global climate alters leading to large-scale death of flora and subsequently the herbivores and carnivores going up the food chain.
It is estimated that three-quarters of all life on earth perished during what is today known as the Cretaceous–Paleogene extinction event. But the event also led to an interesting development. The age of the mammals commenced. Being smaller in size and with less need for sustenance, the surviving mammals who had existed on the peripheries during the dinosaur age got the planet to themselves and started flourishing. The evolutionary path over several subsequent million years took the necessary steps toward modern humans with the ability to walk on two legs.
Writes Rick Potts, the Director of Smithsonian Institute’s Human Origins Program, “East Africa was a setting in foment—one conducive to migrations across Africa during the period when Homo sapiens arose. It seems to have been an ideal setting for the mixing of genes from migrating populations widely spread across the continent. The implication is that the human genome arose in Africa. Everyone is African, and yet not from any one part of Africa.”
The second extinction event that intrigued me was the one in which the human species more or less vanished around seventy thousand years ago. Estimates range from a few hundred to a thousand humans who remained to fend for themselves in a dangerous world. The event is generally linked to a super volcanic eruption named Toba which went off in Indonesia and spewed a colossal amount of ash, debris and vapour into the atmosphere. The Sun got dimmed for years disrupting seasons, choking rivers and killing all vegetation in large parts of the planet.
Says Science writer Sam Kean, “There’s in fact evidence that the average temperature dropped 20-plus degrees in some spots,” after which the great grassy plains of Africa may have shrunk way back, keeping the small bands of humans small and hungry for hundreds, if not thousands of more years.So we almost vanished.”
As I continued to look at that unfurling orange strip and read about the extinction events, I found it indeed amazing how the present world stands dwarfed by close to eight billion of us humans. Even though our footprint remains that tiny blue coloured four-inch block on the timeline representation of life. The probability numbers about a meteor hitting or a super volcano erupting remain minuscule and clearly in our favour because of our small timeline footprint. But within that insignificant (fleeting?) footprint, we have managed to subjugate every other species, harnessing both flora and fauna to our needs. We have mastered science and technology in wondrous ways, improving our lot in every way conceivable. Be it food, be it energy, be it resources, be it our understanding of the Universe.
But could it be that we are willy nilly walking on the extinction pathway of our own making? Stemming from our sheer numbers and our continued actions to reorder and realign nature to our own needs. Vulnerability to increased incidences of diseases and viruses. Vulnerability to our own selves as we fight for scarce resources. Vulnerability from the very technology which we believe we have harnessed.
Scientists and environmentalists are raising the alarm that we may be already at the extinction tipping point arising from global warming and climate change. A tipping point that might lead to the mass extinction of more than half of humanity with the collapse of social, political and economic structures. Once the tipping point is breached, the world could witness accelerating global warming and climate change with no way to control. Simulation studies point to an overall ecological disaster and collapse leading to the mass extinction of a large number of flora and fauna species; more than a million species are on track to go extinct in the coming decades. Would this be Judgment Day for Humanity and its cradle planet?
It seems to me that we have been plain lucky. There really is no certainty of our continuing the domination of the world beyond the so very tiny and fleeting ‘blue block four-inch’ period that we have done so. If our luck was to change, we might just have an epitaph written about us by someone in the distant future. Like the way we have written one about the dinosaurs.
Standing there I was left wondering whether we are creating the right luck for us.
Man who gave you life, man who gave you home
Man who gave you all you desire?
All you do is blight, all you do is waste
Don’t you see the ash of your fire?
Our mother’s crying, our mother’s dying
Our mother’s cancer is true
Mother we belied, mother we defiled
May your human child’s end be good for you
In Musing…………. Shakti Ghosal
8 thoughts on “Extinction”
We need to realize the significance of our existence soon!
So true Paro. Would love to have you write some more.
Was the formation of life itself luck or part of some design. There are essentially seven or so theories all more or less talk about formation of organic compounds which formed basic amino acids and nucleic acids and proteins ,forming basic RNA , replaced by DNA as protein binders . That’s a bit simplistic but then formation of specific inorganic molecules binding together to form basic blocks of life has an almost impossible probability of happening , requiring some very specific conditions to have been met.
Let’s just say that life formed because of at a certain point in the approx 5 billion years those specific conditions were met and the luck of the cosmos washed down the almost impossible probability happening.
Let’s now go on to how life developed over the ages.
Evolution and extinction is interlinked…the more a species evolves into a changing world the less chance is that it would become extinct..
However , it remains a fact that the surviving members of that species would need to get the time to evolve into managing to survive in a changed world Evolution does needs time to really change extinction in to survival of a species.
Have a look at yourself and around you. You are a species of ape evolved from a common ancestor of all apes long extinct know as Hominoidea..from whom various branches of apes evolved. BONOBO and chimps are your closest cousins as species go, as we evolved from the same branch of specie ape.
Yet Homo Sapiens as a species was far more successful as survivers because we evolved fastest. As a species our various branches were exposed to the most varied circumstances and survived. While chimps and bonobos were not.
So we as a species are more successful in surviving.
In today’s changing world do we really have that time?
I believe we do.
It is also a.myth or a concept born of our own egos, an evolved survival trait that’s required for survival, that we are the most successful species, if survival and the propagation of our genes were the only criteria for success as it basically is for all life forms to exsist and survive.
Will leave you with that lovely thought to chew on.
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Thank you for a compelling and scientific argument about extinction and how it is inextricably linked to evolution.
If, as you conjecture, it is probabilistically near impossible for life to emerge on its own, then the question that brooks an answer is, “Who or what was responsible for life to emerge on earth?” My sense is that evolution and extinction might then get linked to that answer.
Aloke, you have indeed opened up a completely new line of thought and argument and I thank you for your presence here.
Very interesting! I wonder which catastrophic event would come first: oceans rising due to climate change, a chance meteor hitting our planet, a virus more lethal than corona, an extinction of bees, artificially intelligent machines taking over, or…. nuclear warfare. Only the next century our so would tell. Or, is my timeline for human extinction too short???
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For Humanity’s as well as our own children’s sake, I do hope and pray that your estimate of the timeline is wrong!
My own sense is that the world is increasingly moving towards a tipping point. Some of its effects in terms of climate change are already there globally. While what might push us over the edge ( virus, extinction of other species, Artificial Intelligence etc.) may not be known ( yet?!?), what we could do about it in the interim is fairly clear. We need to start with building up awareness all around about what we are faced with and the urgent need to be conscious of the environment and sustainability. The much-needed shifts in the social, economic and governance structures need to suitably align here.
I truly appreciate your kind presence here.
Wow! What an informed and informative article. Whenever one gets pumped up, one should look at this, the stars and the immense complexity of even a tiny living cell’s working to be filled with wonder and the realisation of one’s collective insignificance in the enormousness of it all.
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You are so right. If only more of us start looking at the stars and appreciating the wondrous complexity of life, we might indeed mend our ways.
Indeed, the ‘ realisation of one’s collective insignificance in the enormousness of it all…’ might be the start of the much-needed wisdom that Humanity needs at this point in time.
Thank you my friend for your presence here.