The current population of the Earth is over 7.6 billion people and growing. It could reach 8 billion by 2025, 9 billion by 2040, and a whopping 11 billion by 2100. Population is growing rapidly, far outpacing the ability of our planet to support it, given current practices.

Overpopulation is associated with negative environmental and economic outcomes ranging from the impacts of over-farming, deforestation, and water pollution to eutrophication and global warming. While a lot of positive steps are being taken to better ensure the sustainability of humans on our planet, the problem of having too many people has made lasting solutions more challenging to find.

Taking into account the fact that human beings appeared on Earth more than four million years ago, what happened in our recent history for the number of inhabitants on the planet to start multiplying exponentially? The tipping point was generally accepted to be the Industrial Revolution, but there are many smaller revolutions that contributed to population take-off which have brought the planet to its current dangerous overpopulation: revolutions that are medical, technological, agricultural, financial, transport and demographical in nature, among others.

Causes of overpopulation

Overpopulation is mainly referred to trends such as people living longer and enjoying higher live birth rates. Overpopulation of specific locations can also result from migration. Remarkably, the overpopulation of an area can occur without a net gain of population. It can result from a reduction in the carrying capacity of a region, such as reduced agricultural yield due to over farming or drought. Such conditions may lead to an out-migration. In certain countries, the impact of migration and accumulation of the population in cities was very important, but not only with respect to demographic growth, but also in relation to wealth generation. Currently, over half the global population live in cities of more than 300,000 inhabitants and which are expected to continuing growing until they reach 70% of the population.

Environmental effects of overpopulation

Lack of water

Overpopulation creates greater demand on the world’s freshwater supplies. As only roughly 1% of the world’s water is fresh and accessible, this creates a major issue. Some estimates state that human demand for fresh water will stand at approximately 70% of what is available on the planet by 2025. This will place those living in impoverished areas that already have limited access to such water at great risk.