Digitally boosting contrast to better see pterosaur wings

With all the new innovations
in seeing otherwise invisible details using UV, RTI, laser and fluorescing lighting, let’s not forget that Adobe Photoshop can boost contrast after the original digital photograph has been taken. In the present example (Figs. 1-4), the wing membrane is ever so slightly darker than the matrix, but that small range can be increased digitally.

Figure 1. The proximal wing of TMP 2008.41.001 showing original photo, original tracing along with boosted contrast and color tracing.

Figure 1. The proximal wing of TMP 2008.41.001 showing original photo, original tracing along with boosted contrast and color tracing. Nothing changes here, except the interpretation. I say this is data. Hone et al. 2015 wrongly call this ‘shrinkage’. Where is the pteroid? I would X-ray this slab. Based on the propatagium, it is probably buried.

Earlier we looked at
the TMP  2008.41.0001 specimen of Rhamphorhynchus (Hone et al.  2015). Today we’ll just rotate the images to fit the taller-than-wide blogspace format and digitally boost the contrast of the published photos to see what we can see together. Hon et al. traced the same wing membrane borders. Then they said it was ‘fake news’ due to ‘shrinkage’, but only where they wanted it to ‘shrink’.

Figure 3. Right wing and tail of the TM 2008.41.0001 specimen with contrast digitally boosted. Labels and line art from Hone et al. 2016.

Figure 2. Right wing and tail of the TM 2008.41.0001 specimen with contrast digitally boosted. Labels and line art from Hone et al. 2016.

Despite the fact
that this specimen documents a narrow-chord wing membrane stretched between the elbow and wingtip (Fig. 1), no citation to Peters 2002 was provided by Hone et al. 2016, thus fulfilling Bennett’s curse, “You won’t get published and if you do get published, you won’t get cited.”

As readers already know
Dr. David Hone deleted all reference to Peters 2000 when testing the minority view on pterosaur origins (from fenestrasaurs, Peters 2000) versus the majority view (from archosaurs, Bennett 1996), then ascribing both views to Bennett (1996) in a series of two papers (Hone and Benton  2007, 2009) discussed earlier here.

According to Hone et al. (2016):
“Each wing has a more narrow chord along  most of its length than seen in some specimens of Rhamphorhynchus (e.g., BSPG 1938 I 503a, the ‘DarkWing’ specimen—Frey et al., 2003) suggesting some postmortem shrinkage of the membranes (Elgin, Hone & Frey, 2011).”

Unfortunately,
Hone et al did not realize they were looking at a patch of mid-wing membrane in the DarkWing specimen (Fig. 4). We looked at the pre- and post-mortem disarticulation of the ‘DarkWing specimen earlier here.

Of course,
the authors did not forget to cite their own study on wing shape, Elgin, Hone & Frey 2011, in which they considered all examples of a narrow chord wing membrane (that means all examples) caused due to taphonomic ‘shrinkage.’ Their zeal for re-imagining hard data was reviewed earlier here and here.

Figure 2. Left wing of TMP 2008.41.001 showing original photo, original tracing along with boosted contrast and color tracing. Wing tip includes apparently missing wingtip ungual, but there is an articular surface there.

Figure 3. Left wing of TMP 2008.41.001 showing original photo, original tracing along with boosted contrast and color tracing. Wing tip includes apparently missing wingtip ungual, but there is an articular surface there and the membrane extends beyond m4.4.

The wing tip was twisted during burial
rotating the distal elements 180º. This was misinterpreted by Hone and Elgin in their report of the small rhamphorhychid, Bellubrunnus, in which they claimed this was the natural orientation of the wing tip elements in Bellubrunnus. We looked at that unfortunate interpretation earlier here.

Figure 1. The darkwing specimen of Rhamphorhynchus. Top: in situ. Middle: Soft tissues highlighted. Bottom: Neck and forelimb restored.

Figure 4. The darkwing specimen of Rhamphorhynchus. Top: in situ. Middle: Soft tissues highlighted. Bottom: Neck and forelimb restored to the invivo position. Note: the proximal portion is not exposed in situ.  The purple line is drawn based on phylogenetic bracketing. All other pterosaurs have a narrow chord wing membrane.

It is not good for paleontology
when workers ignore hard data.

The Zittel wing

Figure 5. The Zittel wing from a species of Rhamphorhynchus. Click to enlarge. Elgin, Hone and Frey 2011 dismissed this specimen as another example of ‘shrinkage’, but only where they wanted it to shrink.

The other question you should ask,
is why professional paleontologists, PhDs and professors are not calling attention to such issues? It is not good for paleontology when a civilian scientist has to point out such errors of judgement…over and over. Your paleontologists are imagining ‘shrinkage’ wherever they want to and not elsewhere, for some strange reason. Imagine their worst nightmare… backing away from their imaginary interpretations as they begrudgingly accept reality.

IF there was even ONE example
of a pterosaur wing membrane attached at the ankles, I would be the first to tell you about it. So far, all evidence purporting to do so, like the infamous Sordes holotype, has been soundly and thoroughly debunked. Please tell that to the authors listed below, plus any other artists and PhDs who need to know.


References
Elgin RA, Hone DWE and Frey E 2011. The extent of the pterosaur flight membrane. Acta Palaeontologica Polonica 56 (1), 2011: 99-111. doi: 10.4202/app.2009.0145
Hone D, Henderson DM, Therrien F and Habib MB 2015. A specimen of Rhamphorhynchus with soft tissue preservation, stomach contents and a putative coprolite. PeerJ 3:e1191; DOI 10.7717/peerj.1191
Peters D 2002. A New Model for the Evolution of the Pterosaur Wing – with a twist. – Historical Biology 15: 277–301.

https://pterosaurheresies.wordpress.com/2011/11/03/what-the-dark-wing-rhamphorhynchus-tells-us/

 

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.