Dampening the Mood

It has long been believed that animals can predict the weather, changing their behaviour when it is about to rain. Previously there was little evidence to confirm this belief, but new research from the University of São Paulo in Brazil appears to verify it.

The research, published in PLOS ONE, has found that insects avoid having sex just before it rains, or more precisely, they avoid having sex when there is a drop in atmospheric pressure; something that happens just before it rains.

In this study, scientists observed the behaviour of different insect species, and changed the atmospheric pressure while other factors like humidity and temperature were kept constant. Three different species were observed: the curcurbit beetle, the armyworm moth and the potato aphid.

When atmospheric pressure was dropping rapidly, the male insects became less responsive to female pheromones (signalling chemicals, often sexual, like Lynx deodorant for humans apparently) and wouldn’t seek them out to mate.

If placed close to female beetles, the males would mate, but they skipped the normal courtship behaviour and immediately copulated as if they were trying to get it done quickly before a deadly storm arrived.

Female insects reduced their ‘calling behaviour’ (releasing pheromones into the air to attract males), when the pressure was dropping. The scientists think this was because any rain following a drop in pressure would reduce the pheromones’ effectiveness. The drop in pressure could also precede strong winds which could endanger the females themselves. In order to effectively disperse their pheromones, females balance on the edge of leaves, putting them at risk of literally being blown away in strong winds.

So next time your significant other isn’t responding to your advances, you better go bring in the washing off the line because might be about to rain. Alternatively, since your significant other probably isn’t an insect, you should stop using Lynx and expecting them to go crazy.