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Re: Neogondwana and Epitheria (fwd)



I still cannot believe, that evolution of birds and placental mammals was
shaped by breakup of the continents when fauna of dinosaurs and pterosaurs
was often similar between these continents. Aah, probably these placentals
are simply lazy.

On the brighter side, they are cooperative, too: the authors managed to
resolve all the branches between placental orders even if placentals were
supposed to diversify rapidly just after the K-T boundary.

Here common reply to previous posts:

"there is no fossil records of aardwarks, elephant shrews, golden moles
and ternecs from outside Africa"

Common ancestor of these groups evolved from basal Afrotheria after the
original Afrotheria split, so no reason why it should still remain on the
same continent. Second, these four are small, specialised groups with few
species and uncommon fossils - which suggests that their fossils elsewhere
might be undiscovered. Third, ternecs live on Madagascar.

"many flying birds are reluctant to fly over open water"

Which shows that there is only one birder on this list.  Many landbirds
are indeed relucant to fly over open water at day. But the same species
can be night intercontinental migrants (when they live in high latitudes)
and/or colonise oceanic islands. So this behavior obviously does not
preclude the colonisation. Old World examples from various clades: quail
Coturnix coturnix, crakes Porzana & Crex, small owls Otus, Old World
flycatchers and warblers Sylvidae, Muscicapidae). In fact, large number of
endemic rails Rallidae on most remote oceanic islands was explained
precisely by rails' poor flying abilities (and ease to get lost or be
blown off the course).

Jerzy