[Taxacom] Dispersal... again

[Karl Magnacca]

On Tue, 25 Oct 2011, John Grehan wrote:
> To play the worn our record again, dispersal is very popular among
> biogeographers because most biogeographers are not interested in
> analyzing the spatial structure of differentiated entities and
> getting to know the tedious details of distribution (tedious because
> they are so often repetitive). With centers of origin and dispersal
> one is freed up from reading the records of life to make up whatever
> center of origin and dispersal story for an individual group or
> situation without having to worry about those nagging spatial
> incongruities.

Actually, if you remove the anti-dispersal aspersions and spin, in a
sense this is true.  Dispersal is popular because it happens, but
relatively rarely, so it's interesting when it does.  It's what
*creates* incongruities.  Vicariance is ho-hum because it's how
things mostly go.  One more Gondwanan distribution?  Whoop-dee-doo. 
Lizards crossing the Atlantic *after* the split?  Much more notable.

Karl