Tuesday, June 24, 2008

Periodic Cicada Brood XIV - Our Science Report

Thanks to the sleepover at my friend Wendy's house where the cicadas are very plentiful right now, the girls have developed a strong interest in learning more about them. When we got home from Wendy's we took a walk with our butterfly nets and caught a few cicadas and brought them back to the house where they drew pictures of them and wrote information down about them. We looked up cicadas on a couple of web sites and learned the following useful things:

Our cicadas are 17 year cicadas. This particular species and brood (the group that emerged together) is only found in the northeast. They were underground developing and eating tree root sap for the last 17 years before digging holes 4 weeks ago (or so) and emerging. Soon after emerging, they shed their previous skin and left it behind and changed to a dark color. Now they fly around everywhere. The males make the sing-song sound with their wings to attract females. They eat twigs and bark. They will lay more eggs soon which after hatching, will go underground and emerge again in 17 years. The adults will die by the end of the summer. There can be as many as 1.5 million cicadas in 1 acre of land (I believe it at Wendy's house!) Here is the most useful website that talks about our particular brood around us right now:


Watch the video below to see one up close and hear it's song.

Melanie thinks they might be blind or nearly blind because they fly straight at us and whack themselves against things, then land on the ground on their backs and flail around. I can't find any info about their eyesight. So if anyone who is reading this knows the answer to this question, let me know.

Also, I have seen many cicada heads, disconnected from the body, that seem to be still alive. Melanie's friend, Sydney says that if you pull on a back leg the head falls off (as a defense mechanism). I think they would die at this point?? Anyway, another tidbit I can't find any information on.

1 comment:

Amy Young said...

Ewww...I saw a bodyless cicada flopping around in circles at the Thayer's house today! A bunch of ants were surrounding it already, even though it was very much alive..apparently they knew that the end was near for poor Mr. Cicada.
I don't see how this is a practical defense mechanism, as I can't imagine they can do much as a head with wings, but who knows with these things. They're just so...odd. :-)