Human-induced climate change may pose a bigger threat than first believed to plants and global agriculture, a University of Florida scientist says. Evolutionary genetics Professor Pam Soltis, co-author of a study published in the journal Nature, said most flowering plants, trees and agricultural crops may not have the evolutionary traits needed to rapidly respond to human-induced climate change. Many of these plants needed millions of years to evolve mechanisms to cope with freezing temperatures as they radiated into nearly every climate during pre-historic times, she said, and likely acquired many of these adaptive traits prior to their movement into colder regions. "Only some plants were able to make the adjustments to survive in cold climates," Soltis said in a university release Friday. "In fact, some had traits used for other purposes that they co-opted for cold tolerance. The results have implications for plant response to climate change -- some plant lineages, including many crops, will not have the underlying genetic attributes that will allow for rapid responses to climate change." Because evolutionary strategies to resist cold would have taken millions of years, researchers said, it could mean many plants will have trouble with accelerating human-caused climate change. "Some of these changes were probably not as simple as we once thought," Soltis said. "Adjusting to big shifts in their environments is probably not easy for plants to do. "With climate change that is human-induced, all habitats will be affected over a short period of time, and plants and other organisms will have to adapt quickly if they are to survive," she said.