[Taxacom] final thoughts on dispersal and vicariance

[Ken Kinman]

Dear All,
       Thanks to Jason in particular for his various posts on this subject.  And I agree that documenting evidence for a lot of dispersals will take decades (especially the rare ones across the early Atlantic between Africa and South America).  However, it seems like there is a growing consensus that panbiogeographers have clearly overplayed the role of vicariance concerning the post-KT fauna of Madagascar (vertebrates in particular, where the ratio of dispersal to vicariance seems very high).  
       As for my suggestion that aplocheiloid fish could have rafted from Africa to South America, it is just an hypothesis (not a theory), but I consider it an exciting new possibility to explore.  Panbiogeographers like patterns, so I would think a growing pattern of occasional raftings across an early (narrower) Atlantic Ocean would actually interest them, but they continue to even attack growing amounts of evidence that caviomorph rodents and New World monkeys resulted from such raftings.  One recent paper on the fossil evidence regarding caviomorphs is quite interesting and quotes literature on that debate (see weblink below).   
       Anyway, I am frankly tired of trying to convince John and Michael that overplaying the importance of vicariance (especially with regard to Madagascar) is counterproductive, and perhaps makes a lot of people less inclined to read their papers.  So I don't plan to post anything further on dispersal and vicariance.    
                    ---------------Ken Kinman

http://rspb.royalsocietypublishing.org/content/early/2011/10/08/rspb.2011.1732.full.pdf
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