When a meteorite the size of a small town nailed Mexico’s Yukatan peninsula 66 million years ago, our odds of ever walking with dinosaurs abruptly dropped to zero. The upshot? When the impact also decimated the dominant flowering evergreen plant species of the age, it made way for the deciduous forests  many of us live among today, according to researchers from the University of Arizona.

“If you think about a mass extinction caused by catastrophic event such as a meteorite impacting Earth, you might imagine all species are equally likely to die,” said the study’s lead author, Benjamin Blonder. “Survival of the fittest doesn’t apply — the impact is like a reset button. The alternative hypothesis, however, is that some species had properties that enabled them to survive.”

According to their biomechanical research, they found that the plant ecosystem in the 2.2 million years following the meteorite impact was dominated by deciduous species. They hypothesize that their faster-growing angiosperms were better equipped to adapt to the volatile post-apocalyptic environment.

Looking at modern plants, it’s not hard to see why. Plants like holly trees, which have dark, thick leaves, tend to prefer shade and grow slowly. Deciduous plants, with their thinner, more easily replaceable leaves, thrive in sunlight and grow relatively fast.

“When you look at forests around the world today, you don’t see many forests dominated by evergreen flowering plants,” said Blonder. “Instead, they are dominated by deciduous species, plants that lose their leaves at some point during the year.”

It’s believed that the winter-like climate induced by the impact introduced a degree of previously unseen variability. Deciduous plants with their “disposable” leaves were much better able to adapt than flowering evergreens, who employ a “slow but steady” growth strategy in their expensive, carbon-rich leaves.