There is probably a better discussion at
http://www.sciencedaily.com/releases/2009/12/091203132144.htm
'Schaefer says it isn't clear whether the ecotypes will ever become
separate species; in fact, he doubts they will because the habits of
humans will tend to change over time. Even so, the findings do speak
to the long-standing debate about whether geographic separation is
necessary for speciation to occur. In particular, it had been
contentious whether selection could act strongly and consistently
enough in sympatry to separate a united gene pool.
"In highly mobile organisms such as birds, the consensus is that
sympatric speciation is extremely rare, mainly because it is difficult
to envisage how gene pools could be kept separate until speciation has
occurred," Schaefer said. "Our results now show that the initial steps
of speciation can occur very quickly in a highly mobile, migratory
bird," because divergent selection during the overwintering phase
leads to the evolution of reproductive isolation.
"This is a nice example of the speed of evolution," he added. "It is
something that we can see with our own eyes if we only look closely
enough. It doesn't have to take millions of years."'
On 05/12/2009, at 11:51 AM, Ross Macfarlane wrote:
That's not "challenging the conventional view", that's called
sympatric speciation (as opposed to allopatric speciation, which is
the result of geographic separation). It is well and truly part of
"conventional" evolutionary theory:
http://en.wikipedia.org/wiki/Sympatric_speciation
http://en.wikipedia.org/wiki/Allopatric_speciation
But it's not unusual for a science journalist not to know much about
science...
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