Path: utzoo!attcan!uunet!midway!ncar!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!samsung!cs.utexas.edu!helios!n025fc From: n025fc@tamuts.tamu.edu (Kevin Weller) Newsgroups: comp.ai.philosophy Subject: Re: Bird flight as an emergent property Message-ID: Date: 26 Oct 90 00:47:26 GMT References: <1990Oct23.170118.27104@ecn.purdue.edu> <1990Oct24.114805.3306@idayton.field.intel.com> <1990Oct25.100748.2501@jarvis.csri.toronto.edu> Sender: usenet@helios.TAMU.EDU Organization: Texas A&M University Lines: 24 In-reply-to: mccool@dgp.toronto.edu's message of 25 Oct 90 14:07:48 GMT In article <1990Oct25.100748.2501@jarvis.csri.toronto.edu> mccool@dgp.toronto.edu (Michael McCool) writes: > ... > I seem to recall windstream has nothing to do with it; the collective behaviour > is a result of the birds desire to "remain together" balanced against a desire > to avoid collision with each other and objects. And of course, at least in the > case of birds, a minimum speed may be necessary to remain airborne (ignoring > hovering and soaring). Collective "goal-directed" > behaviour, i.e. following a general path or going towards a point (tropism) > is also a factor. > > Anyhow, good luck. > Michael McCool@dgp.toronto.edu Hmmm ... if my memory of zoology class is accurate (it's been a while), birds flying in an "inverted V" pattern do so for aerodynamic reasons. I don't know the physics behind it (yet), but the leader supposedly makes the flying easier on the rest of the flock if they remain in formation. The periodic changeoffs take place to give the original leader a (relative) rest while the new leader takes over the burden. A bird flying by itself must work harder to stay up, significantly harder on long-term (i.e., migration) flights. I will try to find a reference (in my zo book) if you want some real physics. -- Kev