Abstract:
Zoologists have long anguished over the recognItIOn
and significance of strays, lost migrants, dispersing juveniles,
rafting voyagers, etc. Does a migrating bird that is
1000 km from its species' established migration route
represent a potential colonist , a victim of strong winds,
faulty navigation physiology , or a remnant of a population
that has been decimated by recent ecological processes?
Are the insects that invade northern croplands
each summer, only to be extinguished by winter, a part
of a normal natural history being selected for, or is their
invasion merely the serendipitous consequence of traits
with adaptive significances that are quite unrelated to
an invasive natural history? Is a grassland rodent that is
encountered in a rainforest treefall part of a breeding
population or is it as dead as is a physiologically living
rainforest tree seed that is washed up on a Pacific island
beach?