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Re: [dinosaur] Archaeopteryx had active flapping flight ability based on wing bone geometry (free pdf)
On Wed, Mar 14, 2018 at 08:26:22PM +0100, David Marjanovic wrote:
> Gesendet: Mittwoch, 14. März 2018 um 17:25 Uhr
> Von: "Ruben Safir" <ruben@mrbrklyn.com>
>
> > That is with well evolved modern birds, and not all of them at all.
> > Chickens will also do a running take off. Anyway you slice it, unless
> > you have sufficient wing power then launching by leaping has zero value.
> > A bird will land on its face every time. Geese and grouse will also
> > run with wings spread out developing lift.
>
> Having different shoulders from a modern bird, the new paper says,
> *Archaeopteryx*
> did more of a forestroke than an upstroke, and that was enough to eliminate
> the need for a running start... right?
>
I wouldn't know but I would think not. It would have a weaker upward
lift and would need more running room for full flight. Greater lift
and the leaping, especially from stationary position, would likely
co-evolve.
> > The other wrinkle in this conversation is that, if I recall previous
> > discussions, modern birds evolved from waterfowl. Is that still the
> > working hypothesis?
>
> Nope, not in the last 20 years at minimum. The first member of Neornithes
> seems to have been a chicken-/tinamou-like animal. More aquatic birds
> (Hesperornithes, Ichthyornithes) are close to Neornithes, but farther away
> the closest you get to water is *Yanornis*. *Archaeopteryx* and the like show
> no adaptations to a lifestyle that involved bodies of water.
>
I went back took a look at what I could find. The question is what
would exactly survive the k-t event.
https://urldefense.proofpoint.com/v2/url?u=https-3A__www.berkeley.edu_news_berkeleyan_1998_1118_fossil.html&d=DwIDAw&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=YfN-naEvNWO6FEE6Yk9bcCk1cMd4R2StrKRkZr1jiRQ&s=SnCRLvWCrWuJL9AvGm_Ajjj4cIw4LG1wZ3GLOa6MMZ4&e=
This is very old and is perhaps rebuked..