‘Life as we know it will end’ unless we can end the booming population, Dr Jane Goodall has said.
The leading conservationist has warned of more conflicts as people fight over the last parts of fertile land and fresh food and water.
Dr Jane was an early advocate of the argument that a sustainable population is key in the fight against climate change.
Her campaign received a fresh boost yesterday when Prince Harry said that he and Meghan would only have two children for environmental reasons.
Dr Jane told Metro.co.uk: ‘It is predicted that by 2050, there will be 9.7 billion people on the planet.
‘And already we are using up many natural resources before Mother Nature can replenish them.
‘So, if we simply carry on with business as usual, that will be the end of life as we know it.’
The primatologist has said that improving access to birth control is crucial to securing the future of the planet.
She added: ‘Women everywhere must be able to choose whether to have children, how many children, and the spacing between them.
‘This is critical for their own wellbeing. But, they also need to be equipped with the knowledge as to how their choice affects the health of the planet and thus the future of their own children.
‘For we are part of the natural world and rely on its “services” for our very survival.’
Today’s population stands at 7.7 billion people.
The United Nations has estimated that will grow by another two billion in just three decades.
Worldwide an estimated two out of every five pregnancies are unintended.
However, if the average number of children per mother were to decrease by 0.5, the global population would gradually decline to 7.3 billion by 2100.
Growing communities expand into previously untouched forests and habitats, risking the ecosystems and species living there.
A larger population consumes more food and water and creates more waste and carbon emissions.
That contributes to climate change, bringing floods and drought to already vulnerable communities.
Dr Jane highlighted the issue citing her pioneering work with the chimpanzees in Gombe National Park in Tanzania, east Africa.
She said that when her research first began in 1960, it was part of a forest belt that stretched three-quarters of the way across the African continent.
By 1990, she said as she flew over the area, its hills were almost entirely bare and the soil was over-farmed and infertile.
She continued: ‘It was then that I realised that we could not even try to protect the chimpanzees and their habitat unless we could help the people find ways of making a living without destroying the environment.’
The scientist, who is patron of the charity Population Matters, said a child from the west will consume five times the amount of someone from the developing world.
In an interview with Prince Harry for Vogue magazine, she told the royal it was ‘crazy’ to think we can have ‘unlimited economic development’ on a planet with finite natural resources.
In the September edition, guest edited by Meghan, the conservationist added: ‘There’s a lot of violence and war and suffering around the world today, but we’re part of the natural world, and if we can’t learn to live in harmony with it, then this is going to get worse.
‘There will be more conflicts, people fighting over the last fertile land, the last fresh water. It is terrifying.’
Dr Jane was at Windsor Castle for an event with her charity Roots and Shoots, which aims to implement positive changes for people, animals and the environment.
During her time, she paid a visit to cuddle baby Archie and met Prince Harry where he discussed having children.
Dr Jane, a mother of one, then laughed and responded ‘not too many!’
Prince Harry echoed her statements on reducing the population, saying: ‘Two maximum!
He added: ‘I’ve always thought: this place is borrowed. And, surely, being as intelligent as we all are, or as evolved as we all are supposed to be, we should be able to leave something better behind for the next generation.’
Prince Harry’s stance on children is different to his brother Prince William and Kate who already have three and are rumoured to want even more.