Ian Malcolm from Jurassic Park once said, “Life finds a way.” I too have believed this regarding ecological disasters in that our rise wouldn’t have been possible without the one that wiped the dinosaurs out. The environment is important certainly, and all you’d have to do is look at China’s air and soil quality to confirm it. But is there justification for extreme environmentalism or is life and evolution more resilient than we give it credit for? A blog post pointed out a new study that looked at just such a scenario.
The study organism was a single-celled green alga, aka Chlamydomonas reinhardtii. The researchers established lines of this alga that differed in sexuality and the amount of genetic variation. Then, these lines were exposed to a relatively serious environmental change, the salt concentration. Starting with freshwater conditions, a steady increase of salt was implemented to eventually end up with near-marine conditions.
The study authors concluded:
We found that the combination of high initial diversity and obligate sexuality increased the likelihood of evolutionary rescue in populations exposed to a deteriorating environment by increasing their ability to respond to selection.
So what might this mean to us as humans facing the possibility of drastic environmental change? The need for high initial diversity suggests that, as insurance against disaster, people should maintain a portion of as many different populations as possible in genetic isolation while also creating new populations by interbreeding a portion of as many previously isolated populations as possible. A future where all races have been blended and genetic diversity is low (a utopia some liberals dream of) is a prescription for extinction.