Beware the Femme Fatale

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Some female insects are capable of luring unsuspecting males to an unfortunate end by crafty deception.  Male and female fireflies use a kind of Morse code, which tells another firefly the gender of the signalling fly, and whether it comes from their own species.

In one species, after the female has mated, she changes her pattern of signalling to mimic the code used by the female of another species.  When a deceived male of that species approaches, she quickly pounces on him and eats him for supper.  Once these femme fatales have mated they do not respond to the signals of the males of their own species, who remain safe from entrapment.  Hungry female fireflies can quickly change their flash pattern to that of a different species after only a minute or so of observation of a new signal.

The bolas spider catches its prey like the bolas-throwing cowboys of South America.  The female produces a line with a large ball of sticky silk at the end.  The spider lures male moths to her by emitting an odour that mimics the sex pheromones of a female moth.  When a deceived male approaches, the bolas spider swings her sticky ball at the moth.  If the ball hits the moth, the spider hauls it in and paralyses it with a bite before storing it in a silk wrap.

So next time, double check the signals before you act.