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RE: Willie Wonka and the New Papers




AFAIK, the oldest known songbird (Passeriformes) is from the early Eocene of 
Australia (Boles, 1995).


Cheers

Tim



> How about: Origin of Passeriformes lies *in the
> colonization* of Australia, from Borneo (or generally,
> W Indonesia which was more or less contiguous land
> then). Apparently W Wallacea was not yet overwater,
> and the ocean-crossing distance was considerable.
> There was habitat but scant competition in Australia;
> from there ->(Antarctica->)NZ (acanthisittids), ->SE
> Asia/India->Madagascar/Africa->(Sapayoa ancestors)SAm
> (most "OW suboscines") ->Asia (pittas),
> ->Antarctica->SAm->NAm (NW suboscines), and radiating
> in Australia-Melanesia and then -> Eurasia etc
> (oscines).
>
> Plus the earliest European passeriforms, of which
> almost all seem to have been additional very basal
> lineages, "Old World" suboscines, or corvoideans and
> sylvioideans, ->Asia->Europe
>
> Origin of Zygodactylidae then would be the SE Asian
> mainland population of the LCA, which coast-hugging
> south of the Alpides for the most part spread ENE to
> Europe.
>
> This would also tie in with the abundant record of
> what seems to be "near passerines" from mid-Paleocene
> Europe. The entire bulk - rollers, kingfishers,
> woodpeckers, barbets, puffbirds, etc, even trogons and
> toucans, looks like a generally Eurasia-centered
> radiation if one considers the stem lineages which are
> far more frequent in Europe than in NAm (the fossil
> record is rather good on these two continents for the
> time in question), piculet phylogeography etc.
>
> We don't know anything between Zygodactylidae,
> _Neanis_ (if that is indeed so close), Early Oligocene
> woodpeckers, and the 2 Murgon bones. I think as
> outlined above, it requires the least "ghost" record,
> which we do not seem to be able to get around either
> way at present.
>
>
> Incidentially the emerging "near passerine" clade
> shows a number of traits and properties in morphology
> and ecology more frequently than other birds. In
> particular, forefoot anatomy seems to have been
> exceptionally plastic.
>
> But also a strong tendency to be:
> * short-tailed and smallish
> * fairly round-winged and better able to maneuver in
> confined space than to fly long distances
> * perchers on branches rather than skulkers, climbers,
> runners etc
> * inhabitants of subtropical to tropical habitat with
> plenty of trees
> * resident to vagrant; though a capability to evolve
> migration is present, it is less often realized than
> simply adapting to colder climate and staying resident
> * generally sluggish but active when feeding - not
> like e.g. crown Galloanserae which generally move
> about a lot but do not "go after" food but rather
> "happen" across it
> * merrily mixing frugivory and decidedly carnivorous
> habits, as the latter being active hunters of
> everything they can overpower (large invertebrates and
> small vertebrates), without any easily recognizable
> phylogenetic pattern[*]
> * cavity-nesting
> * seasonally monogamous or perhaps permanently
> monogamous
> * diurnal
> * more dependent on eyesight than on hearing in
> interaction with the environment (complex
> vocalizations are limited, but visual signals are
> widespread and important in speciation).
>
> Especially the Passeriformes stand apart. But even
> here, the more basal a lineage diverged, the more
> frequent are these traits in it.
>
>
> Regards,
>
> Eike
>
> [*] This is odd because a trophic switch from
> frugivory (especially strict frugivory as present in
> several lineages here) to mesocarnivory and vice versa
> is not at all trivial metabolically; the genetic
> changes required for it to work might be more complex
> than for changing dactyly (if the nervous system is
> very self-organizing). It would be interesting to give
> it a closer look; there might be a phylogenetic pattern.
>
>
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