So Long, And Thanks For All The Fossil Fuels
Earth Was More Attractive to Aliens Back When Dinosaurs Roamed
They found that two key biomarker pairs would have been stronger some 100 to 300 million years ago: oxygen and methane, and ozone and methane. That's primarily down to a proliferation of greenery delivering significantly higher levels of oxygen into the atmosphere back then.
https://www.sciencealert.com/earth-was-more-attractive-to-aliens-back-when-dinosaurs-roamed #oxygen #methane, #ozone #dinosaurs #aliens #PyewPyew