Thing 3

At the risk of some thinking this site has turned into a some sort of nature tutorial for grade schoolers, here's a few shots taken two nights ago. I was out taking a late night constitutional and happened to spy this male cicada on the pavement under a street light. I know it's a male because only males make their distinctive loud call, (one of the loudest of all insects) and this one let out a few when I picked it up.

Cicadas are really amazing and fascinating insects with a very strange life cycle.

Note the three red dots in a triangle on the top of it's head. These are small simple eyes, as opposed to the larger compound eyes set wide apart on it's head. Despite the fact that they spend the vast majority of their lives underground sucking on roots, they have good eyesight... as you probably would with 5 eyes. (If cicadas wore glasses, would other cicadas razz them by yelling, "Hey, 10 eyes!"?)

Click to enlarge



Leave it to McDonald's to start putting their golden arches logo on insects, for God's sake. Where will it end?




The type of cicadas above typically have a 2-8 year life cycle and are known as annual or dog-day cicadas since they usually emerge in late July or early August.

But there are a couple types which only emerge every 13 or 17 years. Scientists and mathematicians suggest this is no accident. They theorize it's so other species of predators can't syncronize with them and wipe them out. 13 and 17 are prime numbers, divisable only by 1 and themselves. Some suggest that this is a survival mechanism to ensure that they never synch up with the population surges of other predators.

If the cicada emerged every 15 years, say, they'd end up getting hit by predators with a 5 or 3 year population cycle. But by emerging in prime number years, this potentially devastating situation is avoided.

The broods of cicadas have been identified and their ranges mapped, so that each emergence can be predicted. No broods emerged in 2006, but the 17 year brood designated XIII will emerge in this area next summer. Look for cicadas with red eyes. They'll be coming up above ground for the first time in 17 years. So be nice.

More general cicada info here.