Which came first, Facebook or Tyrannosaurus rex?

Tyrannosaurus rex came first, by 68.002 million years. T. rex lived in the last two million years of the age of dinosaurs.

Side by side

Facebook

Facebook launched on 4 February 2004 restricted to Harvard email addresses, opened to other universities through 2004 and 2005, and to anyone over 13 with an email address in September 2006. It is six years younger than Google and a year older than YouTube. Its predecessor Facemash, which compared students' photographs, was shut down by the university within days in 2003.

Tyrannosaurus rex

Tyrannosaurus rex lived from about 68 to 66 million years ago, right at the end of the Cretaceous. Stegosaurus died out around 150 million years ago. That means T. rex is closer in time to us — 66 million years — than it is to Stegosaurus, by more than 20 million years. The two are routinely drawn in the same picture and never met.

Deep-time date, approximate to within a million years or so.