Why Are Tomatoes Red? Blame Meteor Dinosaur-killing impact forced the tomato into big changes, say scientists By Dustin Lushing, Newser Staff Posted Jun 13, 2012 4:16 PM CDT Updated Jun 16, 2012 1:20 PM CDT 26 comments Comments Tomatoes turned red after a giant meteorite landed on Earth 60 to 70 million years ago. (Shutterstock) (Newser) – Why are tomatoes red? The same reason dinosaurs were killed off, say scientists. The massive meteorite that struck Earth 60 to 70 million years ago created extremely harsh conditions that forced the evolution of the tomato into its current red and edible form, reports Phys.org. Researchers discovered this connection by mapping the complete tomato genome and finding that the number of tomato genes suddenly tripled near the time of the meteorite impact. "Such a big genome expansion points to extremely stressful conditions," says one of the researchers. As the theory goes, the solar eclipse that followed the meteorite crash would have made it difficult for plants to live. "A distant ancestor of the tomato plant then reacted by expanding its genome considerably in order to increase its chances of survival." In time, the tomato shed some of the other characteristics it picked up, but its redness stayed.