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Re: Several New Papers



> But how Galliformes could be diversified after KT
> boundary - so, after
> Gondwanan and Lausaria break up - and even so have a
> cosmopolitan
> distribution? Would be ancestral galliform an
> efficient long-range
> flier?

My take on this is that due to paleobiogeography and
(probably) Gondwanan (specifically close to Africa)
origin, it needn't be. From mid-Cretaceous to early
Paleogene, the Atlantic and "Antarctic" oceans were
not too wide to pose a problem, and any lineage that
settled in Africa would be "shipped" close to Eurasia
in the early Paleogene. It is indeed the reason why I
find an Eurasian origin more unlikely, considering the
distribution of the lineages. The megapode lineage is
so near-exclusively Wallacean/Polynesian and appears
to be the oldest of extant galliform lineages. It is
hard to think of a scenario that would produce the
known distribution of galliform lineages from an
Eurasian origin; colonization of N America became
progressively harder and colonization of the southern
hemisphere progressively easier starting in Eurasia
during the Late Cretaceous and going through the
Paleogene.

It is interesting (but probably has not much bearing
on the matter) that galliforms need severe selective
forces to become flightless, much more than even
Passeriformes.

Regards,

Eike




        
                
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