As a species, we are growing at an exponential rate. And the more of us there are, the more resources we devour. Can the world sustain us all?
In 1950, the global population was just shy of 2.6 billion. It now stands at 7.4, which translates to an almost three-fold increase in just 66 years, and the number is growing at a rate of more than one person every second.
More people implies a need for more of everything, starting with space. We don't only need a place in which we can shelter and build our lives, but land on which to grow our food.
And obviously we need to produce more and more of said food (though not if we are just gong to end up throwing it away) to generate a sense of security. That, in turn, means clearing wooded areas to create agricultural land.
But when we fell great swaths of forest, we play a hand in the climate. Mass deforestation results in reduced rainfall - often in places where it is greatly needed - and contributes the warming of the atmosphere.
No rain and a hotter climate equals drought, which means nothing can grow and people are faced with the very real threat of starvation. That scenario leads to mass migration and sometimes armed conflict.
Some analysts believe the ongoing war in South Sudan was partly triggered by the effects of climate change. The conflict, which is in its fourth year and has arleady resulted in mass loss of life, is exacerbated by food and water shortages.
Without those two basics, we cannot survive. And though scientists periodically discover an "earth-like" planet somewhere in the great beyond, the one we currently call home is all we have. That being so, the question remains: how long can it sustain our growing population?
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