More insect breeding found due to warming temperatures

William Atkins
Saturday, 26 December 2009 19:24

Science - Biology

A U.S. study of moths and butterflies in Central Europe found that many of the species studied have produced an extra generation in the summers due to prolonged warming of the region.


Dr. Florian Altermatt, an ecologist from the University of California at Davis reported his findings in the article “Climatic warming increases voltinism in European butterflies and moths” online on December 22, 2009, in the journal Proceedings of the Royal Society B.

Dr. Altermatt and three colleagues were collecting data for a research book when he came across this interesting bit of information.

In all, the four researchers found over 180,000 records from the year 1818 to the present (in museum records and publications) that described over 1,100 species of butterflies and moths around Basel, Switzerland.

Altermatt continued his separate study to make this startling discovery.

And, Altermatt analyzed the warming trend in the area from a weather station in Basel. He found that the mean annual temperature increased about 1.5 degrees since the 1980s--a small but significant temperature increase.

The abstract to Altermatt’s paper states, “Climate change is altering geographical ranges, population dynamics and phenologies of many organisms. For ectotherms, increased ambient temperatures frequently have direct consequences for metabolic rates, activity patterns and developmental rates. Consequently, in many insect species both an earlier beginning and prolongation of seasonal duration occurred in parallel with recent global warming. However, from an ecological and evolutionary perspective, the number of generations (voltinism) and investment into each generation may be even more important than seasonality, since an additional generation per unit time may accelerate population growth or adaptation.”

What is especially interesting is the fact that some of these species have never before (as long as records have been kept) produced an extra generation of offspring at locations in Central Europe.

Page two summarizes Dr. Altermatt's statistics on butterflies and moths in Central Europe.