[CT Birds] N Parula and male birds
ghanisek at rep-am.com
Sun Jun 17 00:05:34 EDT 2012
It's well-established that at least in some situations there are "extra" males floating around waiting for an opportunity to mate. I recall from an ornithology class more than 40 years ago that this was established through a rather blunt experiment, I think in Germany. A circumscribed piece of habtiat was chosen, then the territorial males were killed. It was discovered that they were quickly replaced by other eager males.
More recently it has been learned that what had long been considered monagomous pairings in songbirds are often a bit more complicated. In what amounts to the scientific equivalent of the paternity test on a TV judge show, some females were found to have young in the same nest with different DNA profiles - the result of what has been called "extra-pair copulations." In addition to the primary territory-holding mate, some females manage to mate with another male (or males) as well. Good for genetic diversity, presumably.
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