Readers discuss a guest essay about birthrates and the world’s population. Also: A citizens’ celebration for America’s 250th ...

For centuries, we’ve imagined Neanderthals as distant cousins — a separate species that vanished long ago. But thanks to ...

The United Nations predicts that the global population will reach 9.7 billion by 2050, and further increase to 10.4 billion ...

According to the World Population Review, the world's most populous cities remain concentrated in Asia and Latin America.

The world's population is expected to peak at 10.3 billion in 2084 and then decline to 10.2 billion through the end of the ...