The dinosaur-killing asteroid impact radically altered Earth’s tropical forests
Sun-laden, open-canopied forests were transformed into the dark, dense ones seen today
![tropical rainforest in Colombia](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2021/04/040121_cg_asteriod-rainforest_feat.jpg?fit=1030%2C580&ssl=1)
The origins of modern tropical rainforests, such as this stretch of forest near Medellín, Colombia, trace back to the extinction event at the end of the Cretaceous Period, 66 million years ago.
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