Billionaire Elon Musk posted on Twitter a stern warning about the declining birth rate in rich countries, which he sees as the biggest threat to civilization that should be addressed urgently.

Musk then shared a video of himself on stage suggesting that the world's largest problem in 20 years will be population collapse, in which birth rates slow and mortality rates accelerate, per Tweak Town.

"Population collapse is the biggest threat to civilization," he tweeted.

The shared video was originally posted by An0maly (@LegendaryEnergy), which shows Musk sharing the stage with fellow tech entrepreneur Jack Ma during an event.

The caption reads: "REMINDER: Elon Musk (@elonmusk) for years has been telling people that birth rates are collapsing & most of the media is lying about the population growth problem."

Population collapse is the biggest threat to civilization https://t.co/ZrHN5DsrVB

— Elon Musk (@elonmusk) May 24, 2022

The CEO of SpaceX and Tesla also uploaded to Twitter published data from the Wall Street Journal indicating that the US birthrate has been below "sustainable" levels for more than 50 years.

The World is Heading to a Population Decline

Musk, the world's richest man according to Bloomberg Billionaires' Index, also made that much clear in recent comments during a virtual appearance at the recent All-In Conference held in Miami on May 16.

"We're currently headed towards a population decline. And this is almost everywhere in well in the world."

Musk, who pushed the auto industry to convert to electrification to reduce its environmental impact, disputes the commonly held belief that having a child is costly or that not having children is a decision taken to save the earth, per The Street.

"It basically seems as though as soon as you have like, urbanization and education beyond a certain level and income beyond a certain level, birth rates plummet. And so as countries get wealthier, their birth rates plummet," said the technology mogul, who is a father of seven.

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"It's somewhat counterintuitive because people will say, like, well, 'it's too expensive to have a baby. No. The wealthier they are, the fewer kids you have; the more educated you are, the fewer kids you have," said the 50-year-old father of seven -- Y, X, Griffin, Xavier, Kai, Saxon, and Damian.

"But it's not coming from the humans unless something major changes on the human birth rate level. But this, by the way, is, I think, the biggest single threat to civilization right now," Musk added.

Tesla Developing a Possible Solution

Tesla CEO Elon Musk, who recently offered to purchase Twitter for $44 billion, has regularly brought up the population issue in recent years.

In terms of his entrepreneurial ventures, as per a report from Nikkei Asia, Musk has demonstrated a method of spotting a serious issue of humanity and offering answers to the problem. Hence, Tesla is developing Optimus, a humanoid robot that can perform duties in place of people in anticipation of aging and diminishing populations.

The electric vehicle manufacturer focuses on acquiring artificial intelligence talent, intending to complete a humanoid robot prototype by 2023.

Musk stated during Tesla's quarterly results calls last month that Optimus will eventually be "worth more than" the company's automobile division.

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