During the pandemic, we have discovered what it means to be homebound. The streets have been practically empty and, at the same time, wild animals have been able to return to urban environments. Thus, it is not surprising that many people wonder what would happen to our planet (and our cities, industries and ecosystems) if human beings suddenly disappeared.
Dramatic changes on Earth
There are various theories as to what could lead humanity to extinction, and it is highly unlikely that we will all disappear at once. However, if we imagine that humanity is completely extinct from Earth, many immediate and dramatic changes would probably unfold due to lack of human maintenance.
As Alan Weisman, American journalist and author of ‘The World Without Us’ argues, the subways of large cities such as London or New York would flood within hours, as the pumps that divert rainwater would not work. In fact, according to Weisman, the subways would be completely flooded around 36 hours.
Oil refineries and nuclear plants would also fail, leading to massive fires, explosions and devastating nuclear effects. Similarly, if we were to disappear, we would leave billions of waste, much of it plastic, that would likely affect wildlife.
These pollutants would also have damaging effects on the planet’s habitats, although that does not mean that they were completely destroyed. In fact, you only have to look at the wildlife rebound that has taken place in the Chernobyl nuclear disaster to understand that nature can replenish itself even in extreme circumstances.
At the same time, the water that circulates under the cities would corrode the metallic structures, so that the streets, highways and avenues would collapse and become rivers. During winter the pavement would crack due to frost, so plants and trees could grow on the asphalt ground. Finally, nature would end up making its way, thus destroying the cities. The streets would become small grasslands and the forests would grow in approximately 500 years, as Alan Weisman argues.
Improvement of biodiversity
On the other hand, there would also be a rapid recovery of the insects, since the pesticides would disappear. This, in turn, would favor plants and birds, leading to an increase in biodiversity on a global scale.
In addition, some species such as lions, elephants, tigers or rhinos were found all over the planet before humans began to hunt them and invade their habitats. Without humans, Earth could regain some of its diversity, although it would take millions of years to recover from past extinctions.
