A new study of grasshoppers in the mountains of Colorado shows that, while the answers are complicated, biologists have much of the knowledge they need to make these predictions and prepare for the consequences. The study, published Jan. 30 in PLOS Biology, compares thousands of grasshoppers collected in Colorado between 1958 and 1960 with modern-day specimens. UW Biology Professor Lauren Buckley, postdoctoral researcher Monica Sheffer, and graduate student Julia Smith are co-authors on this study.
From UW News:
As insect populations decrease worldwide — in what some have called an “insect apocalypse” — biologists seek to understand how the six-legged creatures are responding to a warming world and to predict the long-term winners and losers.
“Understanding what species are likely to be winners and losers with climate change has been really challenging so far,” said corresponding author Lauren Buckley, a professor of biology at the University of Washington. “Hopefully this work starts to demonstrate some principles by which we can improve predictions and figure out how to appropriately respond to ecosystem changes stemming from climate change.”
Comparing museum specimens and newly collected insects allowed the research team to assess the impact of 65 years of climate change on the sizes of six species of grasshopper. Because insects are cold-blooded and don’t generate their own heat, their body temperatures and rates of development and growth are more sensitive to warming in the environment.
Despite much speculation that animals will decrease in size to lessen heat stress as the climate warms, the study found that some of the grasshopper species actually grew larger over the decades, taking advantage of an earlier spring to fatten up on greenery.
Growth was seen only in species that overwintered as juveniles and thus could get a head start on chowing down in the spring. Species that hatched in the spring from eggs laid in the fall did not have this advantage and became smaller over the years, likely as a result of vegetation drying up earlier in the summer.
“This research emphasizes that there will certainly be species that are winners and losers, but sub-groups within those species’ populations, depending on their ecological or environmental context, will have different responses,” said co-author Monica Sheffer, a postdoctoral researcher at both the UW and the University of California, Berkeley.
Read the full article in UW News.