After the dinosaurs went extinct as a result of an asteroid
hit the earth, the small mammals had a chance to leave their holes during the
daylight and walked around the surface mostly without the fear of being eaten.
This enabled them to evolve into larger animals and conquer the animal
kingdom. Thanks to that asteroid, we are here now, populating the earth. We
have made significant changes since our existence, we destroyed the big wild
animal herds, we destroyed the natural plant ecosystems and replaced with
farms, we domesticated and created new species. Many animals disappeared
because of our direct or indirect involvement; mammoths, dodos, Tasmanian
wolves, passenger pigeons, quaggas, even homo neanderthalensis, our very human
cousins; the list goes on.
Today 7 billion of us are populating the earth and continue
to deepen our impact into it. But what if our existence comes to a dramatic
end? What would happen, because of whatever reasons, if we disappear in a short
time period, let’s say within a thousand years or so.
In this article, I am only going to talk about the
consequences of our extinction. I am going to write another article soon about
the most realistic reasons how we could go extinct if we did.
First of all, some animals would also disappear with us
forever right after our fall. The human lice and the bed bugs are completely
adapted as human parasites and they cannot survive in a world without humans,
therefore they would quickly go extinct as well. Some endangered species, like
giant pandas today are completely dependent on to human care, especially the
weak baby pandas. Without our protection, they would face the harsh rules of
natural selection and die out in a short time period. Some urban invaders, like
rats and cockroaches, will have a hard time in the absent of human junk,
however thanks to their adaptability to every condition, after some will
perish, the others will readapt to wildlife as they used to be, with a
significantly decreased population.
There are billions of domesticated animals around the world.
We domesticated, cattle, sheep, goats, pigs, chickens mainly to maintain a
secure food source, instead of chasing wild games. Many of those animals also
provide transportation like horses, wools and leather for clothing, and so on.
Dog was probably the first animal ever domesticated, in order to help hunting.
Except dogs, there are many other pets, like cat, goldfish, parakeet and hamster.
Unlike their wild cousins, those animals do not have to search for food, they
are raised and fed by humans. Food and fresh water is not the only thing they
receive, but protection from the carnivores. When humans first started
domesticated them, they did not care about sharp horns and strong legs, but a
fat body that can provide more meat, big breasts for milking, and most
importantly, docile behaviours as they less resist to slaughtering, and they
cherry-picked those for inbreeding. As a result of this, they lost their speed,
strength and adaptability to survive in wild life, and completely dependent on
human activity.
When the humans disappear, all those animals will become
waif and face with serious consequences. At first, as the food and water
provide will be completely cut off, many farm animals will die instantly.
Unlike the wild omnivores, those billions are not adapted to find their own
food, but are fed with corn and soybeans. Right after that, the remaining
population will be an easy target for the wild predators. Unprotected cattle
and sheep will especially increase the number of wolves, dramatically. But when
all cattle and sheep went extinct, many excessive wolves will also die out subsequently
back to a closer population previously. The animal carcasses will feed many
scavengers, like jackals, hyenas, vultures and crows, but again, those will be
temporary, and tend to go back. Some domesticated animals might have quite
different fate, especially the domesticated carnivores. Cats are somehow still luckier to
find their own food, despite many will also die as a result of competition with
the other carnivores, some of them will have a chance to completely turn into
wild and adapt to Mother Nature. Just like dingoes of Australia, as once upon a
time they were also domesticated, some dogs, especially stronger breeds like
german shepherd or husky, will adapt to wildlife and will create new kinds of
wild dogs as a result of interbreeding each other or with wolves and coyotes.
Some of those new generations might superior than wolves and coyotes and might
win the competition as to replace them at the end, similar to the story of
coywolf.
Pigs might also be an exception, as they have been observed that once they break out their fences and escape, they tend much faster to
turn into feral, growing longer hair and even wild boar like tusks. Pig’s diet
is much broader than those cattle or dogs as they are omnivores and much easier
to find their own food in nature. Despite of many fat pigs will perish, many
will survive and turn into a new wild species, and some will interbreed with
wild boars, to generate a stronger breed. Pigs are very smart animals and those
survivor will even be smarter as the smarter ones are likely survive, and transfer
their genes to the following generations. As they also have ability to breed quickly,
they might be a dominant species in the world.
The animal kingdom will not be the only life form under
effect. Many domesticated plants will perish without the humans. Today, most of
the land surface is invaded by farms and plantations, to feed billions of
people and another billions of domesticated animals. Those plants found a chance to
spread over thanks to industrialised and technological farming methods. They
can survive with human irrigation without dependence of rain, they are
regularly fertilized, and they do not have to care about pests and diseases as
much as we care about it.
The human extinction will completely be a disaster for those
farms. In first stage, most of the crops, maize, oats, wheat, barley, etc. will
quickly dry out. As there will be no human to replant the new seeds, they will
go to extinct. Then, the invaders will come, the parasite insects, birds,
omnivores will attack to those undefended ones, without the human protection
and pesticides. The farms will turn into empty soils. The gardens will dry out
and go to wild without human care. Then, the next invaders will appear; the weeds
will freely cover up those newly vacant areas. Those weeds will prevent the
farms turn into natural pastures, meadows and forests for a long time period.
Eventually, it will take hundreds of years for the land turn into forests as it
used to be before the first agricultural revolution. By time, as the structures
and cities continue their slow destruction, the urbanized amazon region of
Brazil and plains of Indian subcontinent will be covered by rainforests, east
coast of the United States by broadleaf forests and east China by bamboo
forests within a thousand years or so. In the great plains of North America,
the bison will again invade large areas as they used to be. The big herds of
the savannah of Africa will also increase and spread their population throughout
the continent. Unlike those areas, the plains of Eurasia will remain empty for
a long time, until evolution of an alternative big mammal, perhaps in a million
years or so.
