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Message: <blockquote data-quote="Accentor" data-source="post: 1941409" data-attributes="member: 81964">In some bird populations, there are consistent differences, some small, some moderate between two or more populations. Yet in many of these species, they are not considered subspecies. At what point does a population become a subspecies? What other criteria are used?I can point to a recent population of Dark-Eye Junco. In the early 80's,a new population established itself in San Diego, Ca. In that time, the birds of this new population have gone through a few changes. Most notably, having less white in the tail, weighing slighly less, having shorter wings and tails, less aggressive behavior and so on. How long will it take for them to at least become a new subspecies and again, is it more than just genetic drift and developing new traits?<a href="http://onlinelibrary.wiley.com/doi/10.1111/j.0030-1299.2007.15910.x/abstract?systemMessage=Due+to+scheduled+maintenance+access+to+the+Wiley+Online+Library+may+be+disrupted+as+follows%3A+Saturday%2C+2+October+-+New+York+0500+EDT+to+0700+EDT%3B+London+1000+BST+to+1200+BST%3B+Singapore+1700+SGT+to+1900+SGT" target="_blank">http://onlinelibrary.wiley.com/doi/10.1111/j.0030-1299.2007.15910.x/abstract?systemMessage=Due+to+scheduled+maintenance+access+to+the+Wiley+Online+Library+may+be+disrupted+as+follows:+Saturday,+2+October+-+New+York+0500+EDT+to+0700+EDT;+London+1000+BST+to+1200+BST;+Singapore+1700+SGT+to+1900+SGT</a>.<a href="http://www.bioone.org/doi/abs/10.1554/03-182?journalCode=evol" target="_blank">http://www.bioone.org/doi/abs/10.1554/03-182?journalCode=evol</a></blockquote>

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