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Re: Archaeopteryx with bird book, was Re: Archaeopteryx flight



Quoting Patrick Norton <ptnorton@suscom-maine.net>:

Tim Williams wrote:

I can answer that question in more than one way. Firstly, there are two separate families of vultures (Old World and New World) that evolved independently. There is also the marabou stork, a scavenging bird that also has a bald head. So, that's three separate examples of baldness associated with scavenging in large birds.<

Although the old and new world vultures are veiwed as not sharing recent common ancestors, the new world vultures are viewed as arising from the stork lineage (see Sibley and Alquist, 1990). So this narrows the list to two taxa of bald headed scavengeres, at most.

True (probably), but to the best of my knowledge, storks are not thought to be
primitively bald-headed (with reversal(s) to feathered heads in most species). So the marabou probably represents an independent acquisition of
bald-headedness.


Nick Pharris
Department of Linguistics
University of Michigan