If you are asked to describe what evolution is, it is likely that you would use some combination of: change, adaptation, natural selection, slow. It can be very easy to think of evolution as being slow: it took a few billion years before creatures large enough to see with the naked eye evolved. Because of this way of thinking, it was feared that living things may not be able to adapt quickly enough to climate change, since we thought that climate change was occurring more rapidly than evolution could. Well, those of us who thought that were wrong.
Evolution can be a very rapid process. In an article published this week in Science (Colautti and Barrett. 2013. Science 342:364-366), purple loosestrife (an invasive wetland species in North America) was found to have rapidly adapted to a more northern climate in the past 100 years. Purple loosestrife was introduced to the United States from Europe, and in the past 100 years, it has migrated north to Ontario. The authors had three field sites spanning from Timmins in the north to 1000 km south at Blandy Experimental Farm. They took purple loosestrife from each location and planted them at all the others, then looked at when they flowered and the number of fruits produced. Purple loosestrife were found to perform best at the location where they were taken from (i.e. plants from Timmins performed best when grown in Timmins compared to the other two groups).
One hundred years is not a lot of time, and given that climate has changed rapidly over this time, it is comforting to see that evolution can keep pace (even if it is an invasive species that was studied). It may be that although the climate is changing and challenging many species, some species will evolve and adapt to new conditions – ecosystems will change. This means that climate change might not cause as much damage to biodiversity in the long-term (some species will and are going extinct, but rapidly evolving species might be okay).
Stay safe and stay informed,