According to a study published in the open-access journal PLoS ONE, insects modify calling and mating behavior in anticipation of storms.
Curcurbit beetle, shown here, the true armyworm moth and the potato aphid can predict adverse weather conditions. Image credit: Melinda Sullivan and Edward Jones, USDA APHIS.
Entomologists led by Dr Ana Cristina Pellegrino from the University of São Paulo studied mating behavior changes in the curcurbit beetle, the true armyworm moth, and the potato aphid under falling, stable, and increasing air pressure conditions.
When they measured the male beetles’ response to female sex pheromones under the different conditions, they found a significant decrease in pheromone response when air pressure fell compared to stable or increasing pressure.
Furthermore, 63 percent of males started copulating faster in the presence of females during dropping atmospheric pressure, a condition associated with high rains and winds. By contrast, under stable or rising air pressure conditions, all males showed full courtship behavior.
Additionally, the amount that female armyworm moths and potato aphids showed mate-attracting behavior was also measured under the three atmospheric conditions.
The female armyworms’ calling was reduced during decreasing air pressure, but the potato aphid showed reduced calling during both decreasing and increasing air pressure, two conditions that can occur with high winds. In both cases, reduced calling went hand-in-hand with reduced mating behavior.
“The results presented show that three very different insect species all modify aspects of their sexual behavior in response to changing barometric pressure,” explained co-author Dr José Maurício Simões Bento from the University of São Paulo.
“However, there is a great deal of interspecific variability in their responses that can be related to differences in size, flight ability and the periodicity of mating.”
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Bibliographic information: Pellegrino AC et al. Weather Forecasting by Insects: Modified Sexual Behaviour in Response to Atmospheric Pressure Changes. PLoS ONE 8 (10): e75004; doi: 10.1371/journal.pone.0075004
