“The world’s population is accelerating towards collapse, but few seem to notice or care,” Musk tweeted.

The world's population is accelerating towards collapse, but few seem to notice or care

— Elon Musk (@elonmusk) July 6, 2017

His gloomy assessment was in response to a November article in New Scientist magazine called “The world in 2076: The population bomb has imploded.”

The piece says that half of the countries in the world have fertility rates below the replacement rate. (In other words, their populations are declining.)

It argues that the world’s population will not continue to rise, as it currently does, but will instead crater by 2076.