Date: Sun, 16 May 2004 12:57:40 -0400 (EDT) From: "Keith F. Lynch" <kfl at KeithLynch.net> To: WSFA members <WSFAlist at WSFA.org> Subject: [WSFA] Re: Cicadas and prime numbers Reply-To: WSFA members <WSFAlist at WSFA.org> Ron Kean wrote: > I remember Keith having offered some explanation, but I had > forgotten the details. And the web sites I googled did not provide > an answer as to why 17 would be so much better than 15, 16, or 18. >From my article in January's WSFA Journal: It's not chance that their return rate is a prime number. A fifteen year locust would be prey for a three year or a five year predator. But a seventeen year locust can only be prey for a seventeen year predator. No doubt one will eventually evolve, drive the locusts to extinction, then go extinct itself. I'm sure this has already happened numerous times over the ages. > http://www.economist.com/displaystory.cfm?story_id=2647052 I see that they've been reading the WSFA Journal. -- Keith F. Lynch - http://keithlynch.net/ Please see http://keithlynch.net/email.html before emailing me.