California went into a five-year drought, laying a perfect framework for studying whether that sudden climate change forced evolutionary changes in the plants. At the end of that time, Franks collected seeds from the same plants, and then planted both the archived and the newly collected seeds in a controlled environment.
"There was an evolutionary shift to earlier flowering time following the drought," Franks said in an interview. Using the wide range of tools now available to geneticists, he was able to determine that the shift was reflected in the genes of the plants, or as biologists would say, the later plants selected (mutations) for earlier flowering.
It wasn't a huge change, ranging from 1.9 days in one group of plants to 8.6 days in another. The scientists call it a "microevolutionary change," but it was significant. Earlier blooming allows the plants to take advantage of a cooler spring, and thus produce stronger seeds that are more likely to survive in a drier climate. It was clearly a case of capturing evolution in the act.
That is precisely the way evolution works. Not giant leaps, but tiny steps.
However, what works for one plant may not necessarily work for another. So the scientists want seeds from many plants to capture the many phases and directions of evolution.
"By rearing samples of ancestral populations, we could resurrect actual genotypes that existed centuries ago," they state in their paper. "Differences between modern and ancestral populations would directly document evolutionary change over known time intervals. We call for an organized effort to accomplish what earlier naturalists did not: systematic collection and preservation of current genetic diversity for future analyses of evolution of phenotypes in conjunction with environmental change."
It could be possible to begin the project on a limited scale, with very little funding, but the scientists believe that would waste precious time. They want to start out on a large scale, involving many institutions and many different types of plants.
"The resurrection approach may be especially pertinent given current global climate change, which is occurring at rates and scales not seen for millennia," they state in their paper.
In other words, the time to strike is now.