Climate Change Impacting Insects
As climate change continues to progress and the earth’s temperature increases, insects and other cold-blooded animals are affected alongside humans. Because their body temperature is determined by the ambient temperature, vital biological processes are also affected in regards to how quickly and efficiently they take place.
A group of Danish and Australian researchers performed a study looking at a number of different insect species to determine whether the frequency of extreme temperature conditions or the changes in the average temperature had the greatest impact on species distribution. The results indicated that the extreme temperature events are the determining factor for distribution of tropical and temperate insect species. In other words, researchers explained, cold-blooded animals are affected by climate change because of the periods of additional extreme weather that are expected in the future.
Ten Drosophila fruit fly species adapted to temperate and tropical regions of Australia. The researchers started by looking at the temperatures under which the Drosophila species are able to sustain growth and reproduction. Next, they looked at the boundaries of tolerance for both hot and cold temperatures. The results were clear. It turns out that the tolerance to very cold or hot weather is what defines the insects’ present distribution. Therefore, the extreme temperature events cause the insects to die, not the average increase in temperature. With additional events expected, this was discouraging news for all 10 species looked at in the study. While the researchers point out that these insects are not thought of as harmful or beneficial organisms to humans, it does indicate a change in the distribution of many species is likely, including those that are of social or commercial importance.