Dino-Killing Meteorite Gave Way to Leafy Forests

The meteorite that killed off the dinosaurs 66 million years ago had more of an effect on evergreens and led plants that lose their leaves to dominate forests, reports a new study.

The event wiped out about half of plant species, and fast-growing deciduous trees replaced evergreens, researchers from the University of Arizona report.

"When you look at forests around the world today, you don't see many forests dominated by evergreen flowering plants," said the study's lead author, Benjamin Blonder from the University of Arizona, in a statement. "Instead, they are dominated by deciduous species, plants that lose their leaves at some point during the year."

Blonder and his colleagues studied 1,000 plant leaves fossilized in southern North Dakota, which are stored at the the Denver Museum of Nature and Science.

"There is a spectrum between fast- and slow-growing species," Blonder said. "There is the 'live fast, die young' strategy and there is the 'slow but steady' strategy. You could compare it to financial strategies investing in stocks versus bonds."

Evergreens take more time to build their leaves and last a long time, the researchers reported. Deciduous plants die sooner, but they're able to move more water and acquire carbon faster.

"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," Blonder said. "Survival of the fittest doesn't apply — the impact is like a reset button. Our study provides evidence of a dramatic shift from slow-growing plants to fast-growing species."

From Discovery News