>I'm not sure that this kind of context exists for the study of
>vagrants per se. It's a fascinating question, though, for
>instance what is the optimum level of vagrancy? If a
>species navigational tools evolve to the level that none
>stray, then the species may be poorly adapted to deal with,
>say, climatic change. On the other hand, if none of the
>members of the species can find "home" and proper habitat,
>the end result is obvious.
>
>So, one would think there'd be an optimal level of vagrancy
>for various species under various conditions of climate
>change, though of course the conditions for selection may
>not have occured. For instance, if predicted global
>warming actually occurs at the rate some scientists expect,
>the pace will be well beyond any past episodes we're aware
>of...nice thought, eh?

Unless I am understanding you incorrectly, I would disagree with your
point. The benefits or costs of a behaviour to a species do not cause the
evolution of actions in individuals. Natural selection works on the
individual, the effect of it working on many individuals of a population is
what drives the evolution of a species. So to study the evolution of
vagrancy you have to ask, how does vagrancy affect the reproductive success
(ability to pass on genes to the next generation) of that individual, or the
strategy being used by that individual. If vagrancy does improve the
abilities of that individual to reproduce then the vagrancy genes will get
passed on and they will become more common in the gene pool, and therefore
the species. The effect may be that the species is able to survive a sudden
warming trend, but this is an outcome of selection on the individual's
actions, not on the species. I am assuming a genetic component of vagrancy
here because this is a prerequisite for evolution (in the strict sense, not
including cultural evolution) to occur.

BTW, thanks for the stormy stories. Its still raining here, suddenly its
like I am back in Vancouver!

Alvaro Jaramillo "You are better off not knowing
Half Moon Bay, CA how sausages and laws are made"
- From fortune cookie, Vancouver
alvaro at quake.net circa 1994
http://www.quake.net/~alvaro/index.html