Earth is now officially populated with at least eight billion living humans.
According to the United Nations (UN), there’s now more people sharing this planet than ever before.
But is this a good thing or a bad thing?
What’s happened?
The United Nations announced on November 15 that the world’s population officially reached eight billion people – the most the Earth has ever held.
For context, there were one billion people in 1800.
“The milestone is an occasion to celebrate diversity and advancements while considering humanity’s shared responsibility for the planet,” the UN’s secretary-general Antonio Guterres said.
What caused this?
It all comes down to improvements in public health, nutrition, personal hygiene and medicine (which extended human lifespan) – as well as “high and persistent levels of fertility” in some countries, according to the UN.
Child mortality, infant mortality and maternal mortality have all decreased, too.
So it’s actually a huge achievement even if it seems like a daunting number, and suggests people are living longer everywhere with a better quality of life, not just in developed countries.
However, there are still wide discrepancies in health care access, resources, violence, conflict, poverty and ill health, according to the UN.
Where is the population growing the most?
It is countries with the highest fertility rates which seem to be driving population rates – and unfortunately, they’re usually the ones with the lowest income per capita.
It’s projected that more than half of the expected growth in population up to 2050 will be concentrated in eight countries: the Democratic Republic of the Congo, Ethiopia, Pakistan, Egypt, India, Nigeria, the Philippines and Tanzania.
So, what about the rest of the world?
More than 60% of the global population is already living in a country that is below replacement fertility. That means people are not having enough babies to maintain their current population levels.
More than 50 countries are in population decline, too.
This usually comes down to women’s education and development. The more opportunities she is able to enjoy, the fewer children she is likely to have.
What does this mean?
Where there is rapid population growth, the UN’s sustainable development goals – 17 markers aimed to increase the quality of life for humans everywhere – is under greater pressure.
But equally, where the population has plateaued, environmental goals come under larger threats.
As The UN notes: “Even though population growth magnifies the environmental impact of economic development, rising per capita incomes are the main driver of unsustainable patterns of production and consumption.”
Basically that means the wealthier a country becomes, the smaller the population is likely to become. But, those with the highest per capita consumption of material resources and greenhouse gas emissions also tend to be those where the income is higher.
So,it will be harder to stick to the promises from the Paris Agreement to reduce global temperature rise to just 1.5C, as the world gets richer.
There is also still a stark disparity between the median age in developed and less developed nations. For instance, 41.7 years is the median age in Europe, while in sub-Saharan Africa, it is 17 years. This shows there’s still a long way to go before the quality of life for people around the world is on a more equal footing.
Will the population keep going up and up?
No, but it will keep rising for the rest of the 21st Century, based on current predictions – albeit at a slower rate than we’ve seen so far.
It only took the world 12 years to bloom from seven to eight billion, but the UN predicts the world’s population will grow to around 8.5 billion in 2030, reaching nine billion in 2037.
By 2050, it will be around 9.7 billion, before peaking at around 10.4 billion in the 2080s, and plateauing at this level until 2100.
While this rate is slowing, it is still a lot of extra people on the planet.
“It would be a catastrophe if governments can’t prepare for what’s coming in the next few decades,” Dr Rachel Snow, from the UN Population Fund, warned.
After that, it’s unclear – but if more of the world has equal access to resources and opportunities, it’s likely to start shrinking.
Will we eventually worry about underpopulation?
Birth rates are admittedly slowing down.
The population grew by the largest amount back in 1964, when it was growing at more than 2.2% per year. For comparison, it’s now increasing by less than 1%.
But, reduced birth rates for women is a sign of greater female rights, and that’s essential for sustainability, according to Dr Snow.
And, as the UN said: “Slower population growth over many decades could help to mitigate the further accumulation of environmental damage in the second half of the current century.”