Tech billionaire Elon Musk hasnot been quietabout his belief that low nascence rates could be humanity ’s downfall . Now , however , he has a newfangled concern : what if turn down giving birth charge per unit think of that we wo n’t have enough multitude to populate Mars ?

In a Twitter thread on Tuesday , Musk wrote that he trust that we should be much more worried about universe collapse than we are .

" UN projections are utter nonsense , " hewrote . " Just multiply last yr ’s nativity by lifetime expectancy . Given downward trend in birth rate , that is proficient case unless reverse . "

" If there are n’t enough people for Earth , then there definitely wo n’t be enough for Mars [ Frowning face ] . "

So far , just 0 mankind have gone to the Red Planet , but this has n’t stopped   Musk from take he could put1 million people up there by 2050on spaceships subject of carry 1,000 people at a time . A million may not sound like a lot to ask ( in comparison to the million on Earth today ) , but Musk is clearly worried that the Martian projection will not happen if birthrates here on Earth decay .

In the 1950s , women worldwide on medium had 4.7 fry over the course of their lifetime . late research has shown that the birth rate rate was nearly one-half of that at 2.4 in 2017 , and the same team projected that the full fertilityrate would be 1.6 . Any act lower thanaround 2.1 , and the population begin to decline . The squad predicted that   the population will top out in 2064 at 9.73 billion before this decay happen .

While a challenge – particularly in wish to how we search after anaging universe – others are implicated about how an ever - growing universe can be maintain on Earth .

" All of our environmental problems become easy to solve with fewer people , " David Attenboroughfamously ( and polemically ) said . " And harder – and ultimately impossible – to clear with ever more hoi polloi . ”

Musk , meanwhile , believes that a decline in our numbers is a menace to our universe .

“ I think one of the grown risks to culture is the low-pitched birthrate and the rapidly wane birthrate , ” hesaid in December 2021 .

“ And yet , so many multitude , include overbold people , intend that there are too many people in the humans and think that the population is growing out of control . It ’s completely the opposite .

“ Please see at the numbers – if hoi polloi do n’t have more children , civilization is run low to tumble , score my words . ”