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I think it will be important to cover the fuller range of stories related to global climate change than is covered in the mainstream media, which focuses mainly on disaster scenarios. Understanding what might happen is important, mainly for the pressure it places on all of us to find ways to change and adapt (which is unpleasant for us short-lived humans), but the natural world has always made it its business to adapt to constant change. The plant kingdom, for instance, has faced several periods of global warming and its opposite-- ice ages. There are lesons to be learned, there. We understand the response as natural selection, but focusing on that endpoint rather than the means misses something really amazing about the plant world-- the genetic and biochemical machinery it has to successfully respond to change. For instance, as the ozone layer thins, more UV radiation strikes the earth's surface, where it can cause destructive changes to DNA in both humans and plants. Many plants, however, respond with a class of organic chemicals called polyphenols, which absorb UV and disarms its effects. Plants use those polyphenols, and we've identified thousands of different forms, for many purposes besides UV "sunscreen," such as defense (plant makes itself taste bad), attracting bees (polyphenols are the basis of scent and color), wounding etc. In fact, one of the most amazing facts I've read is how a plant can tell the difference between a scissor wound (scientist snips a leaf sample), where there is no polyphenol response, and a bite wound from a caterpillar, where the bug's saliva causes a big polyphenol response to dissuade the bug from eating the plant. Other wound responses include creating polyphenols that attract the predators of the attacker. It's like calling in a big brother or a fixer to take care of a bully. An insect walking across one leaf can cause all the adjacent leaves of a plant to manufacture foul-tasting polyphenols. It's the plant's version of a gunslinger's quick draw. Likewise, as temperatures and moisture conditions change, even in very modest ways at this point, we already are seeing reports of amazing adaptations by plants. They aren't waiting for some crisis point in global warming-- they are busy now even as I write. The thing about polyphenols is that many of them are very good, even vital, for humans. They are the carotenoids and vitamin antioxidants in our diet, like vitamins A, C and E, as well as the antioxidants we seek in wine and green tea. Interestingly, we know now that a diet rich in plant polyphenols can work in humans as an internal sunscreen, giving the skin a natural SPF of 15, just like they work in plants. Wherever UV exposure is increasing because of the disappearing ozone layer, plants will be making more polyphenols. It's a whole new rationale for eating bioregional foods and being a "locavore." It's also a wake-up call for all of us to make every effort to protect every remaining shred of plant biodiversity that we have so carelessly destroyed-- we need those plants to have every capability at their disposal to respond to climate change in order to help maintain human life. Through the threat of climate change we've finally discovered the real value (to us) of genetic biodiversity. Granted, the oft cited claim of "potential new drugs" is a good one, but now we are in the real-time process of witnessing its real power-- the plant world's ability to respond to environmental change using its arsenal of thousands of biochemicals.

My point is, since we are a major cause of global warming, we tend to think ony humans have any solutions. If you look at how humans evolved and migrated to new areas following receding glaciers or even massive wild fires, it's clear that can't be so. The plant and animal kingdoms had to first make the necessary adaptations before humans could enter new areas and find something to dine on. Plants are, and always have been, natural sources and sinks for nitrogen and carbon, the two main players in global warming. When the global nitrogen and carbon cyles change, plants change, individually and as communities, in order to survice. We need to start treating them with more respect for what they do for us, learn from their adaptations, and revalue the landscapes they create, which, through their roles in maintaining global carbon and nitrogen cycles, serve purposes higher than humans at present can comprehend. Peat bogs are just one example.

No doubt there will be plant heroes unrelated to those we value for food and fiber that climate change will finally make us notice, communities of which will create new sinks for carbon dioxide and nitrogen, the basic building blocks of life for plants and soil microbes. As we face climate change, a little fear is not such a bad thing, so long as it drives us to appropriate change and opens our eyes to our necessary relationship with the natural world. We need to respect and protect it, and, most of all, step back and let it do its thing.