Sunday 11 August 2024

Cicada



Constantly heard but very rarely seen. In the summer, their singing is constant, so much so that it becomes background noise and you stop hearing it. But, it's very rare to see one and I can count sightings on the fingers of one hand. This one landed on the awning of our front terrace - which is very unusual as they typically live in trees - and stayed there all evening. I don't know if that's something they do, or whether it was injured. In the morning it was gone.

I welcomed the chance to study its transparent membranous wings,  and its prominent eyes that are set wide apart.

As I mentioned earlier, their song is exceptionally loud and it's produced by the rapid buckling and unbuckling of drum-like tymbals. It's produced by the males and it's a courting song. Although only males produce the cicadas' distinctive sounds, both sexes have tympana by which they detect sounds, the equivalent of having ears. Males disable their own tympana while calling, thereby preventing damage to their hearing - a necessity partly because some cicadas produce sounds up to 120 dB which is among the loudest of all insect-produced sounds. The song is apparently loud enough to cause permanent hearing loss in humans should the cicada be at 'close range'.



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