Seven little lessons to rediscover our everyday life.
Seven days for the Creation… of a new perspective.
DAY 6 – THE ANIMALS OF THE EARTH
The well-known detail: A friend of yours posts alarming news on Facebook: due to overpopulation, the number of the living would now have exceeded that of the dead. It honestly seems an exaggeration, and yet you are curious: how many people have lived and died in the whole history of humanity?
The background: This is a rather controversial empirical calculation <fn>An excellent study on the history of the calculation of the dead, and its socio-political implications, is How Many People Have Lived on Earth?, by Oded Carmeli, Haaretz, 11 October 2018.</fn>, which might easily be interpreted for political purposes (or distorted—if necessary—to make more or less plausible predictions about the future of humanity). Furthermore, there are intrinsic methodological problems: the further one goes back in time, the more difficult it is to estimate the effective population size, population growth and life expectancy, not to mention the remotest prehistory in which the same concept of homo sapiens seems to vanish.
If we want a reference number anyway, we can refer to a study by the Population Reference Bureau published in 2018, according to which the number of living human beings (7 and a half billion at the time of the estimate) would constitute about 6.9% of the people born throughout history. The total number of human beings ever appeared on the Planet would therefore be 108.6 billion, of which 101 billion are already dead. The afterlife, it must be said, seems to be quite crowded and its ranks grow with every passing second. <fn>If you want to know the data updated in real time, go and check worldometers.info.</fn>
But these figures fade if we think of how many animals and plants there are in the world.
Our planet has a radius of 6371 km; the portion that allows life, starting from the air (the lower layers of the atmosphere), passing through the surface and reaching the subsoil, is just 20 km high.
So the biosphere turns out to be just a very thin layer that covers the Earth, yet it houses an inconceivable number of living creatures.
It is estimated that the living species are approximately 8.7 million, of which 370,000 are plants, 23,000 fish, 8700 birds, 6300 reptiles, 4500 mammals, 3000 amphibians, 900,000 insects and 500,000 belong to other taxonomic groups.
We’ve managed to discover and catalogue only a small part of all these species: 86% of land creatures and 91% of marine creatures are still unknown. And many of these will be forever, because climate change is accelerating the process of extinction: many species are disappearing in this very moment, without our having ever noticed their existence.
If the sheer number of species is impressive, the figures become even more inconceivable if we consider the number of specimens for each species.
Let’s focus on animals, for example: how many are there? Once again, we cannot know for sure, but considering insects might give us a rough idea. Ants are about 10,000 quadrillion (that is, million billion). Based on this figure, some scientists estimate that the total number of insects amounts to 10 quintillion, or 10 billion billion.
These are just the insects, to which we must add all other animals—from eagles to squids, from men to reptiles—plants, fungi, protozoa, chromista, bacteria…
The numbers go beyond understanding and we are only ever considering living creatures.
Now try and imagine how many plants and animals have died from the moment life appeared on Earth… if you can.
The Sixth Lesson: Dismantling fake news on overpopulation is easy, but it opens up a dizzying amount of numbers. The biosphere in which we live is at the same time a ‘thanatosphere’: it almost takes your breath away to contemplate the immeasurable quantity of death that supports the swarm of life and melts with it. On the other hand, none of the creatures that have inhabited the planet in the past million years has ever really gone away, they are all still in circulation. This life is already an afterlife.