[Taxacom] Columbiformes, ghost moths, Madagascar, etc.

[Kenneth Kinman]

Hi Michael,  
       (1)  I wasn't suggesting that the fossa could have eliminated
Columba on its own, but along with other predators (like the mongooses,
civet, etc.).  And again, I suggest that it wasn't necessary to
eliminate a well-established Columba species if the predators simply
prevented the population from being well-established in the first place
(nipping the population in the bud, so the speak).             
     (2) Yes, I think there are plenty of cases of vicariance explaining
the distribution of taxa, instead of dispersal.  The New Zealand wrens
that we discussed is a great example.  But Madagascar became isolated
much earlier than New Zealand, so I think the vertebrate fauna of
Madagascar (especially mammals and birds) is much more the result is
dispersal.  I would expect more vicariance among the other vertebrate
groups which have been around longer (Jurassic or earlier).  
         -------Ken               
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Michael wrote:      
     The fossa may possibly have eliminated Columba from Madagascar, but
Columba thrives in Africa where there are many different kinds of cats -
five families of feliforms as opposed to just one (branching halfway up
the phylogeny) on Madagascar - and it's hard to imagine that the fossa
could wipe out Columba when these have not. 
  
Are there any areas or patterns where you accept a vicariance
explanation for many of the groups? In most patterns the clades involved
all show different degres of differentiation, so in an evolutionary
clock model there cannot have been vicariance. This seems to be quite
good evidence against a clock model.