Re: [dinosaur] Archaeopteryx had active flapping flight ability based on wing bone geometry (free pdf)

[Tim Williams <tijawi@gmail.com>]

Ruben Safir <ruben@mrbrklyn.com> wrote:

> swans, 100% need a running start to get in the air.

I highly recommend you read both Earls (2000) and Dececchi et al.
(2016).  Your statement may hold for swans, but there is no reason to
believe that a running take-off is primitive for birds.  Rather, it
appears to be a derived behavior, restricted to certain birds.  In
this context, Earls actually mentions swans specifically: "Second, a
running take-off of the type proposed in evolutionary hypotheses is
seen in select groups of living birds that are morphologically
specialized (e.g. albatrosses, loons), that are taking off from highly
compliant surfaces (e.g. water) or that are very large (e.g. swans)."

I'd add that 'weak' fliers among modern birds are capable of a
stationary take-off - such as the near-flightless lyrebirds (I've seen
this firsthand).


> I think that Archaeopteryx would need a similar take off.

There is no reason to think that _Archaeopteryx required a running
take-off.  I'm bewildered why you continue to assert this.  Check out
Dececchi et al. (2016), which explicitly addresses why a stationary
take-off was eminently possible for _Archaeopteryx_.


> suggests to me that it lived on the ground and likely was able to fly
> from island to island in the warm European Caribbean like topography.

Here I do agree with you.


> It might be in trees, especially for nesting.

This is highly doubtful.  Arboreal nesting is likely to be a derived
behavior; basal avialans like _Archaeopteryx_ probably retained egg
deposition in sediment/soil (e.g. see Mayr 2107 DOI
10.1007/s10682-016-9872-1).


> But it doesn't have great
> enough efficiency of a launch mechanism to routinely reach tree tops.

I don't see why _Archaeopteryx_ couldn't have flown up into a tree.
It could have flown up there by flapping its wings - a short burst, as
posited by Voeten &c (the paper that started this thread) .  The
initial launch just gets it into the air.


> They would be climbing up the tree like a squirrel.

This is extremely doubtful.  The idea that _Archaeopteryx_ (or any
other basal bird) climbed like a squirrel is utterly fanciful.  This
absurd idea was dealt with by Chiappe et al. (1999) regarding the
alleged squirrel-like posture of _Confuciusornis_.  More broadly,
Dececchi & Larsson (2011 doi:10.1371/journal.pone.0022292)
comprehensively refuted the notion that basal birds were adept
quadrupedal tree-climbers.