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Re: Shaking up the bird family tree



David Marjanovic wrote:

<The tenth of the eighteen authors weighs in: 
http://groups.google.com/group/talk.origins/msg/7e514d3ce1c0f17e>

>From that, Harshman writes:

<3. Finally, it's been claimed that our phylogeny shows that tinamous,
flying relatives of the flightless ratites, must have gained flight
independently of other birds. It's much simpler to suppose that various
groups of ratites lost flight independently, a much less shocking
conclusion. (By the way, we have a paper coming out next month in PNAS
that will look into this in detail.)>

  The problem here is that to argue that flight is lost, you must have 1) a 
single gaining of flight, 2) loss of flight in ostriches, 3) loss of flight in 
rheas, and 4) loss of flight in the cassowary/kiwi/emu clade. This is more 
steps than a simpler explanation in which tinamous gained flight after the 
whole lost it. A tad more parsimonious, rather.

  Cheers,

  Jaime A. Headden