Rain more important than heat for evolution
We already know that climate change affects animals and plants in several different ways. A research team has now taken a closer look at how climate factors can affect evolution itself, i.e. natural and sexual selection.
Together with colleagues from the US, Erik Svensson, professor at Lund University’s Faculty of Science, has found out that climatic variations in precipitation and humidity probably play a greater role in evolution than previously thought, and that these factors could be more significant than changes in temperature in explaining the power of natural and sexual selection.
The new study shows that global and regional climate factors in the form of precipitation and humidity affect selection in all groups of organisms. These effects cover plants as well as birds, reptiles, mammals and invertebrates.
‟It was surprising to observe that selection is not more affected by variations in temperature on Earth”, says Erik Svensson.
One explanation could be that cold-blooded animals such as insects can regulate their body temperature by seeking out shady locations to avoid overheating. Their behaviour thereby counteracts and weakens the power of natural selection.
‟It is perhaps not as easy for these organisms to protect themselves against increased or decreased rainfall or drought”, says Erik Svensson.
The findings from the new study can be used to understand how the current and future climate might affect animals and plants in various regions. Rapid climate or environmental changes could result in stronger natural selection, which could be a challenge for many organisms.
‟If there is insufficient genetic variation with regard to the ability to survive these changes, it could lead to an increased risk of extinction for many species”, says Erik Svensson.
Text: Lena Björk Blixt, Helena Bergqvist