Hone 2020 reviews anurognathid pterosaurs

Here’s a new paper from Dr. DWE Hone (2020).
Quoting Hone’s own publicity sheet regarding the paper, “there’s not a huge amount to talk about here since as it’s a review, it doesn’t contain too much that’s new.”

Even so,
Hone manages to promote invalid pterosaur myths, like the pushup-takeoff (Fig. 1) and the presence of a giant eyeball in the front of the skull (Bennett 2007, Fig. 1). That was repaired here and here (Fig. 1) several years ago. The purported scleral (eyeball) ring is in fact the maxilla in the smaller flat-head SMNS 81928 specimen (Fig. 1) incorrectly referred to the genus Anurognathus (Figs. 3a, b) by Bennett 2007 and repeated by Hone 2020. Correcting the eyeball problem resulted in a traditional dimorphodontid/ anurognathid-type skull (Fig. 1 top figures) despite the skull being flatter than tall, a morphology repeated several times in later anurognathid discoveries.

Bennett presented a unique morphology
(not shared with any other pterosaur) that was copied and embraced by Witton and Hone without question. Both PhDs should have done their own scientific research instead of trusting anyone under this simple rule: “Extraordinary claims require ordinary evidence.” Yes, ordinary evidence. Just confirm or refute Bennett’s bizarre observation with your own tracing of the specimen and compare that with other similar taxa. That’s what PhDs are paid to do. To trust unique claims like Bennett 2007 without a second examination is not scientific.

Figure 1. The SMNS 81928 anurognathid specimen.

Figure 1. The SMNS 81928 anurognathid specimen, two interpretations shown slightly larger than life size. This was the first of several ‘flathead’ anurognathids to be discovered. Let’s hope the blue one can open its wings and start flapping before the eventual face plant. And how did such a take-off configuration evolve from bipedal ancestors?

In summary, Hone 2020
reviews the history of anurognathid research and renames a specimen. Hone promotes previous mistakes (Fig. 1) as valid without support from new, confirming tracings or any tracings whatsoever. Only one taxon is reconstructed (Fig. 1). No phylogenetic analysis appears. The IVPP transitional anurognathid embryo is ignored along with several other basal anurognathids (Fig. 4). Some citations are omitted (see way below). All the above shortcomings and mistakes were resolved online here and at links therein several years ago.

From the Hone 2020 Abstract:
“The anurognathids are an enigmatic and distinctive clade of small, non‐pterodactyloid pterosaurs with an unusual combination of anatomical traits in the head, neck, wings and tail.”

No. After precise tracings and phylogenetic analysis in the large pterosaur tree (LPT, 251 taxa), anurognathids are not enigmas, not all are small, the traditional clade Pterodactyloidea is invalid because it is polyphyletic (Peters 2007, LPT) and there is no reason to trust Hone’s description of the head, neck, wings and tail given his use of M Witton’s invalid illustration (Figs. 1, 2).

Compare Hone and Witton’s published anurognathids
(Figs. 1, 2) with more precise tracings (Figs. 1, 3) of the skeletal and soft-tissue elements of the Anurognathus holotype (Figs. 3a, 3b) distinct from the smaller disc-head SMNS 81928 specimen (Figs. 1, 3b), both from Solnhofen limestones.

Figure 1. From Hone 2020, illustration by M Witton of Jeholopterus. Compare to figure 2.

Figure 2. From Hone 2020, illustration by M Witton of Anurognathus, not the holotype, but the SMNS 81928 as in figure 1.

Witton and Bennett 9007 place the eyeball over the maxilla
in the large antorbital fenestra, rather than further back in the orbit, as in all other pterosaurs, over the jugal (Fig. 3a cyan), behind the lacrimal (Fig. 3a pink).

Figure 2. Click to enlarge. DGS tracing of Anurognathus ammonia. Note the placement of the lacrimals in the skull, behind the large antorbital fenestra. That is not the orbit. The small jugal (bright light blue) also indicates the placement of the small orbit in the back half of the skull, as in all other anurognathids. Also note the disappearance of the cervicals beneath the matrix. That may be an embryo by the tail. More on that tomorrow.

Figure 3a. Click to enlarge. DGS tracing of Anurognathus ammonia. Note the placement of the lacrimals in the skull, behind the large antorbital fenestra. That is not the orbit. The small jugal (bright light blue) also indicates the placement of the small orbit in the back half of the skull, as in all other anurognathids. Also note the disappearance of the cervicals beneath the matrix. That may be an embryo by the tail. More on that tomorrow.

Figure 1. The flat-head pterosaur, a private specimen (on the left) attributed by Bennett (2007) to Anurognathus ammoni (on the right).

Figure 3b. The flat-head pterosaur, a private specimen (on the left) attributed by Bennett (2007) to Anurognathus ammoni (on the right). Pedal digit 5 does not frame a membrane. Rotodactylus and other bipedal Jurassic pterosaur  tracks show how it impresses.

Hone 2020 abstract continues:
“They [anurognathids] are known from very limited remains and few have been described in detail, and as a result, much of their biology remains uncertain.

If pterosaur expert, Dr. Hone, doesn’t want to go to the effort, and wants to ignore workers who have gone to the effort years earlier (Figs. 1-4), before too long Dr. Hone will not be known as the expert he trained to be and thinks he is.

“This is despite their importance as potentially one of the earliest branches of pterosaur evolution or even lying close to the origins of pterodactyloids.

Well, which is it? Basal or transitional? A bit of effort, like creating a cladogram, would have resolved this issue. Hone has a PhD in paleontology. He should not leave things vague and unanswered. This is his passion and his job and he is not doing his job or following his passion.

“This review covers the taxonomy and palaeoecology of the anurognathids, which remain an interesting branch of pterosaurian evolution.”

Hone defined the Anurognathidae,
“as all taxa more closely related to Anurognathus than Dimorphodon, Pterodactylus or Scaphognathus.” That would include all of the taxa (and a few more recent ones) shown in figure 4. Many of these did not appear in the Hone 2020 review, which was intended to be comprehensive.

Figure 2. Click to enlarge. Anurognathids to scale. The adult of the IVPP embryo is 8x the size of the embryo, as in all other tested adult/embryo pairings.

Figure 4. Click to enlarge. Anurognathids to scale. The adult of the IVPP embryo is 8x the size of the embryo, as in all other tested adult/embryo pairings.

See below for comments
on Hone’s self-published publicity statement, which summarizes his paper and arrived a few days before the PDF became available.


References
Bennett SC 2007. A second specimen of the pterosaur Anurognathus ammoni. Paläontologische Zeitschrift 81(4):376-398.
Hone DWE 2020. A review of the taxonomy and palaeoecology of the Anurognathidae (Reptilia, Pterosauria). Acta Geologica Sinica (English edition)
https://onlinelibrary.wiley.com/doi/epdf/10.1111/1755-6724.14585?saml_referrer

From DWE Hone’s publication announcement:
“Revising the frog-mouthed pterosaurs: the anurognathids”

Oops. This paper is not a revision. Hone 2020 is titled, “A review of the taxonomy and palaeoecology of the Anurognathidae”. A revision would revise present thinking. Hone himself notes he makes no attempt to do this. Let’s imagine Hone was thinking of the word ‘reviewing’ when he wrote the PR piece, but inserted the more exciting word ‘revising’ by accident.

“The anurognathids are a wonderful group of small non-pterodactyloid pterosaurs known from Europe and various parts of Asia that are perhaps the most distinctive of the early pterosaur groups and probably the latest survivors.

According to the large pterosaur tree (LPT) and simple logic, several clades of Middle and Late Jurassic pterosaurs gave rise to four pterodactyloid-grade clades, some of which extended to the last day of the Cretaceous. You don’t get Cretaceous pterosaurs without Jurassic and Triassic ancestors. Anurognathids also invaded North and South America, according to phylogenetic analysis and footprints.

“They had bizarrely short and broad skulls made of tiny spars of bone and with few teeth and remarkably short tails for non-pterodactyloids. They were mostly small and are interpreted as having been hawking for insect prey on the wing. There are few specimens (even with the recent discoveries) that are hard to tell apart because they are all so similar and yet almost every different specimen has been named as a new species.”

Hone puts no effort (no tracings, a single borrowed reconstruction, no original cladograms) into understanding, reconstructing, modeling, lumping and splitting the several known anurognathid specimens. As in prior studies, Hone stands back when scientific work is required. Hone’s writing is only in service and support to his traditional bias. He avoided citing several peer-reviewed studies that included other anurognathid materials (see below). Bottom line: Hone is supposed to be a scientist, not a journalist. He should be shedding new light on anurognathids, resolving the enigmas, not repeating what others have already published. That’s what journalists do.

“So they are both really unusual and not very well known and that means even if this has taken time to come to fruition, a review of them would be rather handy. And so as you might imagine, this post coincides with a new paper doing exactly that. Somewhat inevitably there’s not a huge amount to talk about here since as it’s a review, it doesn’t contain too much that’s new – the primary role is to bring things together and synthesise them so most of what is there is already known (at least to people who keep up with the pterosaur literature). Reading the review will bring you up speed if you want all the basics, but I do want to talk here about a couple of the more interesting things I have added.”

“The first one is the validity of the various taxa. It’s hardly unknown for pterosaur clades to be made up of lots of species each represented by only a single specimen but the anurognathids are pushing even that. While I can’t immediately think of any calls for synonymy of any taxa, the fact that so few specimens have been described in detail and the poor quality of the preservation of many means that the available lists of diagnoses have been pretty weak to date.

In counterpoint, detailed tracings and reconstructions have been online for every known anurognathid (Fig. 4) for several years. Hone omitted several of these taxa. A cladogram would have helped him separate in-groups from out-groups.

“They are not much better now, but I have at least revised and updated the diagnosis of every taxon. There are two consequences of this that are important. First off, all the current taxa seem valid, and moreover, some of the recently illustrated, but not yet named, specimens also look like they are distinct taxa and there’s probably several new names needed. Secondly, the second species of Dendrorhynchoides, D. mutodongensis is as distinct, if not more so, than many other anurognathid genera and as such needs to be elevated to the genus level… I erected the new genus Luopterus to house the species.

That’s a good name for a specimen needing a new generic name. Well done, Dave!

“Next up, the variation in the different species is quite odd. Anurognathids are weirdly conservative, even compared to other pterosaur groups and while the poor preservation of the specimens hasn’t helped up find distinguishing traits between them, once you sit down and really look it’s hard to find the kinds of traits that you might normally use to separate out genera and species.”

Seeking traits to separate specimens is “Pulling a Larry Martin“. Don’t do that. It leads to madness due to convergence, or, in this case, backing away from what must be done: a comprehensive phylogenetic analysis with all the anurognathid taxa and parts thereof laid out, lumped and separated.

“That said, there are some bits of variation which while commented on before are quite notable in this context (and there is more coming on this in a future paper that I’m involved in). The length of the tail is really variable and while these are as a whole short-tailed (even the longest of them is much shorter than other non-pterodactyloids) there is really quite some difference between the longest and the shortest. I don’t know what this means but it’s an area worthy of greater attention.

Unfortunately, Hone only crudely illustrates the variety found in anurognathid humerus shapes, but omits doing the same for the tails, or any other body parts, especially the skulls. If an amateur can do it (Figs. 1–4), a paid professional and a PhD should be able to do it that much better.

“Similarly, the smaller anurognathids tend to have extraordinarily large heads and the larger ones rather small ones.

This needed to be illustrated and documented. Reconstructions (see Fig. 4) do not reflect and confirm Hone’s observation.

“There could be ontogentic effects here since many of the smaller specimens are juveniles but it stands in contrast with the more general isometry of other pterosaurs, and could be linked to prey sizes or even eye size. If they are, any [sic] many people suspect, nocturnal then juveniles need huge heads to house huge eyes.”

Hone is correct with regard to pterosaur isometry, so why then does he label some pterosaurs ‘juveniles’, rather than small adults of distinct genera? The huge eyes guess is easily resolved by tracing each specimen and locating the eyes, none of which are ‘huge”, with the exceptions of Batrachognathus (Fig. 5) having the most owl-like eyes and most binocular. Even so, those eyes remain in the back half of the skull, as in ALL other pterosaurs.

Dorsal and lateral views of three anurognathid pterosaurs.

Figure 5. Dorsal and lateral views of three anurognathid pterosaurs. From left to right, Dendrorhynchoides, Batrachognathus and Jeholopterus, all crushed dorsoventrally, due to the skull’s greater width.

Hone continues
“Finally, there is the issue of the ‘folded’ wings. While some disarticulation can occur in decaying pterosaurs unless the specimen has disintegrated the various bones of the wing finger stay together. Presumably they are held together by numerous strong ligaments or they would not be able to hold up the forces of flight. It’s a very derived condition since of course all other archosaurs (indeed tetrapods generally) can flex their fingers.

Pterosaurs are not archosaurs. This is yet another myth Hone promotes without citing competing studies. He tried to do so once, but choked on the attempt, kowtowing to the agenda of his professor and mentor, Mike Benton. Hone has not been under the influence of Benton for over a decade, so he should show a little independence now. As a PhD pterosaur expert, knowing what a pterosaur is… that is his job and he is not doing his job. More on the wing issue below.

Anurognathids however, despite having some exquisitely preserved specimens, and nearly all of them being basically articulated, show the joints of the wing finger being flexed. This suggests that they are doing something really rather different with their wings, when flying or even when on the ground.

Not at all. The small size of most anurognathids means the wing finger did not need to be as robust as in the larger clades. That alone could account for the flexion seen in many anurognathid wing phalanges (Figs. 4, 6). There’s also taphonomy. And speaking of wings, no pterosaur fossil shows the wing membrane extending down the thigh to the ankle, as shown in the Witton illustrations (Figs. 1, 2).

Tracing of Jeholopterus using DGS.

Figure 6. Click to enlarge. Tracing of Jeholopterus using DGS. Dorsal view of Jeholopterus based on the tracing. Lower left images include an unidentified pair of semi-circles too large to be embryo upper temporal fenestrae (that was the first guess). The tail is not particularly short when stretched to its full length, despite the reduced length of the individual caudals. The red ellipse represents a hypothetical egg shape. The abdomen was not so wide. The ribs would have had a ventral component and direction, which they do not have here. Note the right angle femoral head, ideal for parasagittal locomotion, like a dinosaur.

“One thing to note is that this is also seen in one other set of pterosaur specimens – embryos. That implies that either anurognathids have inherited this trait from their ancestors (if they are, as some suggest, the first branching group of pterosaurs) or have secondarily acquired what is essentially a paedomorphic trait of wing flexion.”

If Hone had produced a valid cladogram, like the LPT, he would have been able to find a solution to his own problem. See figure 4 for a quick graphic review.

“I’ll leave it there for now. There’s plenty more in the paper that you can read and there is obviously more research to come (indeed I’m working on another anurognathid paper that’s come about in part through this work) so don’t want to go over this in detail when it’s already a review. Hopefully this does sort out a few issues and pave the way for a better understanding of these most interesting of pterosaurs.”

In counterpoint, and allowing for a little verbal showmanship on Hone’s part (e.g. using “revising” instead of “reviewing” in his PR ), all pterosaurs should be equally interesting because taxon omission by PhDs is a traditional sin. Granted, Hone is infatuated with anurognathids, like the proud father of any new paper generally should be. Unfortunately, because this paper is already in print, it is now too late to give it the care and attention it should have had when still in his mind and on his monitor.

David Hone is still a young man.
I hope that someday he will see the light, crawl out of Benton’s shadow, do the work he is paid to do, stop hiding behind taxon and citation omission, and ultimately become the pterosaur expert he trained to be.


Papers and abstracts omitted by Hone 2020
Peters D 1995. Wing shape in pterosaurs. Nature 374, 315-316.
Peters D 2000a. Description and Interpretation of Interphalangeal Lines in Tetrapods.  Ichnos 7:11-41.
Peters D 2000b. A Redescription of Four Prolacertiform Genera and Implications for Pterosaur Phylogenesis. Rivista Italiana di Paleontologia e Stratigrafia 106 (3): 293–336.
Peters D 2002. A New Model for the Evolution of the Pterosaur Wing – with a twist. – Historical Biology 15: 277–301.
Peters D 2003. The Chinese vampire and other overlooked pterosaur ptreasures. ournal of Vertebrate Paleontology, 23(3):87.
Peters D 2007. The origin and radiation of the Pterosauria. In D. Hone ed. Flugsaurier. The Wellnhofer pterosaur meeting, 2007, Munich, Germany. p. 27.
Peters D 2009. A reinterpretation of pteroid articulation in pterosaurs. Journal of Vertebrate Paleontology 29:1327-1330.
Peters D 2010. In defence of parallel interphalangeal lines.
Historical Biology iFirst article, 2010, 1–6 DOI: 10.1080/08912961003663500
Peters D 2011. A Catalog of Pterosaur Pedes for Trackmaker Identification
Ichnos 18(2):114-141. http://dx.doi.org/10.1080/10420940.2011.573605

See a pattern here?
Kids, if you want to get cited, get your PhD and go with the traditional bias and flow. Be willing to ignore competing citations if they come from outsiders who are willing to do the work and go the extra mile without getting paid [heavy on the sarcasm here, for those who are thinking about quote-mining this paragraph].

Geographic cladogram of pterosaurs

So many pterosaurs come from so few places.
And those places are spread around the world. So, here (Fig. 1) is the large pterosaur tree (LPT, 239 taxa) with color boxes surrounding Solnhofen, Chinese, North American, South American and other geographic areas where they are found.

Figure 1. LPT with pterosaurs colorized according to geography.

Figure 1. LPT with pterosaurs colorized according to geography.

As before,
the traditional clades ‘Pterodactyloidea’ and ‘Monofenestrata‘ become polyphyletic when traditionally omitted taxa are included. Here (Fig. 1) four clades achieve the pterodactyloid-grade by convergence. Other pterosaur workers (all PhDs) omit or refuse to include most of these taxa, leading to false positives for the tree topologies they recover. Moreover, none recognize, nor cite literature for, the validated outgroup members for the Pterosauria (Fig. 1) preferring to imagine pterosaurs arising from unidentified and/or invalidated archosaurs or archosauriforms. Here we get to peak beneath the curtain.


References
Peters D 2000a. Description and Interpretation of Interphalangeal Lines in Tetrapods.  Ichnos 7:11-41.
Peters D 2000b. A Redescription of Four Prolacertiform Genera and Implications for Pterosaur Phylogenesis. Rivista Italiana di Paleontologia e Stratigrafia 106 (3): 293–336.
Peters D 2007. The origin and radiation of the Pterosauria. In D. Hone ed. Flugsaurier. The Wellnhofer pterosaur meeting, 2007, Munich, Germany. p. 27.

If you want to learn about pterosaurs, start with this one.

Still unnamed
the privately-held ‘Painten pterodactyl’ (Tischlinger and Frey 2013) is a perfectly articulated small specimen (Figs. 1-4). Phylogenetically it nests in the large pterosaur tree (LPT, 232 taxa) at the base of the clade that leads to Pterodactylus (Fig. 5), just off the path toward Germanodactylus…and it’s not too far removed from its Scaphognathus ancestors (Fig. 5).

If you want to learn about pterosaurs,
start with this one (Figs. 1-4). The Painten pterodactyl makes it easy to see all the bones in natural (undisturbed) articulation. Even the sternal complex (magenta) is visible below all the other pectoral bones.

Figure 1. The Painten pterosaur specimen in situ under visible and UV light, then under DGS to identify the bones with colors.

Figure 1. The Painten pterosaur specimen in situ under visible and UV light, then under DGS to identify the bones with colors.

The skull
has the standard premaxilla with four teeth per side. Traditionally overlooked tiny secondary nares are visible. The temporal arch is very low on the skull.

Figure 2. Painten pterosaur skull.

Figure 2. Painten pterosaur skull. Only the palate remains buried in this excellent example of a preparator’s skill and perfect preservation.

The wrist
(Fig. 3) includes an excellent vestigial manual digit 5 curled up on the palmar side of the left hand. That is an unexpected taphonomic displacement because in vivo digit 5 would be on the axially torsioned dorsal side of the manus. The vestige appears to be coming up around the crushed edge where metacarpal 5 is buried underneath. The carpals and digit 5 show some dislocation, which may explain how the remains of digit 5 ended up on the palmar side of the manus.

Figure 3. The wrist of the Painten pterosaur. Here the vestige of manual digit 5 (blue) is clearly visible on the palmar side of the left wrist.

Figure 3. The wrist of the Painten pterosaur. Here the vestige of manual digit 5 (blue) is clearly visible on the palmar side of the left wrist.

The feet, tail and wingtips
include a disarticulated bone from the base of the tail. Unguals tipped all five pedal digits. one wing bone (m4.4) was broken and healed in life.

Figure 4. The feet and tail of the Painten pterosaur with colors applied to bones. One loose proximal tail bone (red) is displaced at left. Left manual 4.4 is broken and re-healed in a jagged fashion. The wing tips are large, pulley-like joints. The wing unguals (dark blue) are displaced.

Figure 4. The feet and tail of the Painten pterosaur with colors applied to bones. One loose proximal tail bone (red) is displaced at left. Left manual 4.4 is broken and re-healed in a jagged fashion. The wing tips are large, pulley-like joints…or are those round unguals now lacking tips? Only a closer look will tell, but the tips seem to have neck-like indentations.

We first looked at
the Painten pro-pterodactylid here in March, 2014.

The disappearance of the maxilla ascending process
and the appearance of the tiny secondary naris and nasal descending process appear during phylogenetic miniaturization in this clade.

Figure 6. Painten pterosaur ancestors and descendants.

Figure 5. Painten pterosaur ancestors and descendants. The development of  the secondary naris is documented in the smaller Scaphognathus, which needs a new generic name.  The naris becomes confluent with the antorbital fenestra when the ascending process of the maxilla disappears and the descending stem of the nasal is retained (in some taxa). Other pterodactyloid-grade pterosaurs had a convergent apparent confluence of the naris.

With the majority of the confluent fenestra
devoted to the naris, perhaps we should think of this opening differently.

Figure 6. The Painten pterosaur phylogenetically nests between two smaller specimens in the LPT. 

Figure 6. The Painten pterosaur phylogenetically nests between two smaller specimens in the LPT.

Big compared to its sisters,
the Painten pterosaur is the last in this lineage to have robust cervicals, based on comparison to Ningchengopterus (Fig. 6), a taxon closer to the many Solnhofen pterodactylids in museum collections (Fig. 7). This phylogenetic variety exhibited with Solnhofen and Chinese pterosaurs suggests a wide distribution for this clade in the Late Jurassic.

The Pterodactylus lineage and mislabeled specimens formerly attributed to this "wastebasket" genus

Figure 7 Click to enlarge. The Pterodactylus lineage and mislabeled specimens formerly attributed to this “wastebasket” genus

In summary
This pterosaur is an ideal teaching  specimen because it has all of its bones in articulation and nests at a transitional node in pterosaur phylogeny.

References
Tischlinger H and Frey E 2013.  Ein neuer Pterosaurier mit Mosaikmerkmalen basaler und pterodactyloider Pterosauria aus dem Ober-Kimmeridgium von Painten (Oberpfalz, Deutschland) — A new pterosaur with mosaic characters of basal and pterodactyloid pterosauria from the Upper Kimmeridgian of Painten (Upper Palatinate, Germany) Archaeopteryx 31:1-13.

 

Unwin 2017: Early origin of pterodactyloid bauplan

Unforunately Dr. David Unwin has brought us

  1. the invalid Monofenestrata
  2. Darwinopterus as the transitional taxon linking long-tails to short-tails.
  3. Modular evolution
  4. a 1994 continuation of the deep chord wing membrane misinterpretation of Sordes

From the Unwin 2017 abstract:
“The origin of the pterodactyloid bauplan from that of non-monofenestratan (‘rhamphorhynchoid’) pterosaurs involved extensive anatomical changes and had profound consequences for the evolutionary history of Pterodactyloidea,”

Not really. Phylogenetic analysis shows it happened gradually four times. So there is no clade. “Pterodactyloidea.” Dr. Unwin is way out of date with the latest research.

“Evolution of the pterodactyloid skull construction predates the Middle Jurassic, but remains almost completely undocumented by fossils.”

Not really. Dr. Unwin does not include a sufficient number of tiny adult pterosaur taxa. Traditionally he has ignored the tiny transitional taxa that document the origin of the pterodactyloid-grade. He does not want to accept that this grade has been attained four times and two other clades, Anurognathidae and Wukongopteridae, evolve some, but not all pterodactyloid-grade traits.

Liaodactylus reveals that innovation in pterodactyloid skull anatomy and the appearance of derived features was well underway prior to the Upper Jurassic. Douzhanopterus, a derived NPM, demonstrates that elongation of the metacarpus and reduction of the tail and fifth toe (classic pterodactyloid synapomorphies) also predates the Upper Jurassic, but disjunction in the degree of their development across taxa is not consistent with simple explanations such as ‘adaptation for flight’. Overall, late Early to early Late Jurassic pterosaurs were much more diverse and had a far more complex evolutionary history than heretofore recognized.”

Figure 1. Douzhanopterus at top in situ compared to scale with related pterosaurs, including Jianchangopterus, Ningchengopterus and the Painten pterosaur, all at the base of the Pterodactylidae.

Figure 1. Douzhanopterus at top in situ compared to scale with related pterosaurs, including Jianchangopterus, Ningchengopterus and the Painten pterosaur, all at the base of the Pterodactylidae.

Not really. 
Peters 2007 recognized the ‘far more complex evolutionary history’ that Unwin has yet to accept.

Earlier we looked at Douzhanopterus (Late Jurassic) and found it nested among the primitive members of the Pterodactylus clade. Earlier we looked at Liaodactylus, which nested among the Ctenochasmatidae.

Dr. Unwin still doesn’t get the big picture
due to taxon exclusion in his analyses. Pterodactyloid-grade pterosaurs had four origins (azhdarchids and ctenochasmatids arising from Dorygnathus. Scaphognathus gives rise to pterodactylids and germanodactylids, which give rise to  tapejarids and pteranodontids. This topology has been in the literature since Peters 2007, and online since 2011 at ReptileEvolution.com. If you know Dr. Unwin, please steer him gently in that direction.

References
Unwin D 2017. The complicated and surprisingly early origin of the pterodactyloid bauplan. SVPCA-SPPC Birmingham, abstracts September 12-15, 2017.
Peters D 2007. The origin and radiation of the Pterosauria. Flugsaurier. The Wellnhofer Pterosaur Meeting, Munich 27 online here. (Please ignore the notes on Jesairosaurus and Drepanosauridae, which no longer nest with the pterosaur clade. The latest info is here and here.)
Unwin DM and Bakhurina NN 1994. Sordes pilosus and the nature of the pterosaur flight apparatus. Nature 371: 62-64.

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Data denial you can listen to on a podcast

Dr. Mark Witton

Dr. Mark Witton

Dr. Mark Witton is a paleontologist,
author and illustrator, but based on a Liz Martin interview podcast denies the existence of pterosaur ancestors. Like his friends, Dr. David Hone (another data denier), and Dr. Darren Naish, Dr. Witton believes pterosaurs “appeared fully formed in the fossil record. We don’t have the pterosaur Archaeopteryx.”

Sadly this purposefully ignores 
the published literature (Peters 2000 is now 15 years old) online phylogenetic analyses (now 4 years old) and YouTube videos (just a few weeks old) that all provide a long list of pterosaur ancestors that demonstrate a gradual accumulation of pterosaur traits. Why does Dr. Witton prefers to hide his head in the sand rather than examine, test and/or accept published studies? Could this be academic bigotry? (definition: intolerance toward those who hold different opinions from oneself)

Witton believes pterosaurs “are close relatives of dinosaurs.”
If so, then were are the common ancestors that show a gradual accumulation of character traits? Answer: You can’t find them because they are not there. Other taxa share more traits with pteros and dinos than either does with each other. This is the outmoded “Ornithodira” concept.
Witton says he did not expect
that the Jurassic pterosaur, Dimorphodon would be adept at walking on the ground (despite having digitigrade pedes and fully interned femoral heads). Again, published literature demonstrates just the opposite (Padian 1983). Glad to see that Dr. Witton is getting on board with a more terrestrial Dimorphodon.
Dr. Witton waxed on about Solnhofen juvenile and subadult pterosaurs,
agreeing with Bennett (1995) who lumped Rhamphorhynchus into one species by plotting long bone lengths on a graph. Witton thought different species should have a dramatic difference in wing shape. Not so. He didn’t mention foot shape and overall morphology, which varies quite widely and logically when phylogenetic analysis is employed (Fig. 2).
Figure 3. Bennett 1975 determined that all these Rhamphorhynchus specimens were conspecific and that all differences could be attributed to ontogeny, otherwise known as growth to maturity and old age. Thus only the two largest specimens were adults. O'Sullivan and Martill took the brave step of erecting a new species. The n52 specimen is at the lower right. Click to enlarge.

Figure 2 Bennett 1975 determined that all these Rhamphorhynchus specimens were conspecific and that all differences could be attributed to ontogeny, otherwise known as growth to maturity and old age. Thus only the two largest specimens here were adults. Witton agrees that all these are conspecific. Do you agree with Witton? Decide for yourself. Click to enlarge.

Witton follows the Lü et al. (2009) analysis
that nested Darwinopterus as a transitional fossil combination of pterodactyloid skull and basal pterosaur post crania. Other analyses ( Wang et al 2009, Andres 2013, Peters online) do not support that hypothesis. Only Peters online (based on Peters 2007) includes a large selection of sparrow-sized Solnhofen pterosaurs, keys to the origin of all later clades. Along the same lines, Witton believes in Modular Evolution, which is falsified in phylogenetic analysis and apparently occurs only in their vision of Darwinopterus.
Witton reports that some azhdarchids had short necks.
Not sure which azhdarchids he is talking about. Evidently that is sneak preview on unpublished papers. The large pterosaur tree indicates that going back to the Late Jurassic, all azhdarchids and their ancestors had very long necks, even as hand-sized taxa (Fig. 3).
The Azhdarchidae.

Figure 3. The Azhdarchidae. Click to enlarge. No short necks here, except way down toward the left. Not saying they could not evolve. Just saying I haven’t seen them yet. 

Witton reports there are small birds but no small pterosaurs
from the Upper Cretaceous — but no small dinosaurs either — so suggests there may be a preservational bias in the lack of small pterosaurs… but no such bias for small birds. Actually there are small bird fossils from the Late Cretaceous, and they ARE dinosaurs, and no small pterosaurs. Lacking tiny pteros in the Late Cretaceous spelled their doom. Only small and tiny pterosaurs survived the Latest Jurassic extinction event and only these were basal to later giants. So no darwinopterids had descendants in the Cretaceous. Because there were no tiny Late Cretaceous pterosaurs, none survived the Late Cretaceous extinction event.
Can we blame this on a bad mentor?
Dr. Witton has accumulated a great deal of pterosaur knowledge and expresses it wonderfully in his many paintings. Unfortunately, like Hone and Naish, he was ‘raised’ by wrong-minded mentors and continues his false beliefs (= he has not tested his or competing hypotheses in phylogenetic analyses) to this day. Earlier we looked at the many problems in Dr. Witton’s book on pterosaurs.
Dr. Don Prothero

Dr. Don Prothero

Some insight into that sort of thinking…
it’s not that uncommon.
Dr. Don Prothero in a YouTube Video provides great insights into the Creationist mindset that finds strong parallels in the current thinking of Dr. Mark Witton, Dr. David Hone and Dr. Darren Naish.

Notes from the Prothero video
  1. Humans are not rational machines
  2. We all employ motivated (emotional, wants and needs) reasoning, not logical reasoning
  3. We are all belief engines and we all create a world view or core belief
  4. Because of that we don’t like to hear anything that does not fit our world view
  5. AND we use reason to do what we want data to do, not what its telling us. We use ANY tricks to make the evidence of the world fit our beliefs, or twist it to fit, or deny it or ignore it. Michael Shermer, founder of the Skeptics Society and author of “The Believing Brain” writes, “We all support the world we already have.”

Bottom line:
Witton, Hone and Naish don’t like ReptileEvolution.com because it doesn’t support the paleo world they already have. Like Creationists they display the following traits raised by Prothero:

  1. Reduction of cognitive dissonance (= the state of having inconsistent thoughts, beliefs, or attitudes, especially as relating to behavioral decisions and attitude change) when presented with evidence that works against that belief, the new evidence cannot be accepted.
  2. Tribalism = we learn our world from whoever we were raised by. And all three professors are friends of one another.
  3. Deep innate psychological tendencies are genetic = there are some people who readily accept new ideas and there are some people who do not. Unfortunately, all three appear to have the same gene.
  4. Confirmation bias (= the tendency to interpret new evidence as confirmation of one’s existing beliefs or theories.) Thus when Hone and Benton (2007, 2009) come out with the worst paper I have reviewed, Naish and Witton support it anyway.
  5. Cherry picking (= remembering the hits, forgetting the misses). Hone, Witton and Naish like to pick on poor Longisquama, which was difficult, but not impossible to interpret and all three like to ignore the whole point of ReptileEvolution.com, the cladograms, both the large reptile tree and the large pterosaur tree. Note that no other pterosaur worker has produced competing interpretations of Longisquama of equal detail nor competing cladograms that include tiny pterosaurs. In this regard these pterosaur workers are exactly like Dr. Feduccia and the late Dr. Martin (who deny the theropod-bird link and never employ phylogenetic analysis) and also like extant Creationists, who likewise never employ phylogenetic analysis. Remember when Hone and Benton first deleted the taxa that Peters 2000 proposed, then deleted Peters 2000 from the competition? This was cherry picking at its best.
  6. Qiuote mining (= in this case finding images and hypotheses that have been long ago trashed in order to undermine the site. These are essentially ad hominem (directed against a person rather than the position they are maintaining) attacks as they blackwash my methods (which they practice too) and the entire website while they could have gotten specific about one problem or another.
  7. Missing the forest for the trees (= The big picture) is the large reptile tree cladogram. This is created by a huge mass of data and becomes strengthened with every additional taxon – all of which affect every other taxon. In such an analysis you can remove data, remove taxa, remove characters and nothing falls apart. The subsets are just as strong as the dataset itself. But Hone, Naish and Witton refuse to acknowledge that, preferring to continue their thinking that pterosaurs appeared suddenly in the fossil record, like on the fourth day of Creation. Phylogenetic analysis would solve their quandary, if only they would give it a chance.

Dr. Prothero asks: Why is science different?
Prothero answers his own question in this fashion:

  1. Science (like ReptileEvolution.com) is always testing with falsification, prove things wrong, correcting mistakes. Presently I’ve made over 50,000 corrections in drawings and scores and look forward to many more. Getting it right is important.
  2. Science (like ReptileEvolution.com) is always tentative, no claim to final truth. I am always looking for a competing hypothesis. Witton, Hone, Naish, Bennett and other referees are making sure my papers are not getting published. They don’t like it when their claims are disputed here at PterosaurHeresies.
  3. Science (like ReptileEvolution.com) works! It provides answers that make sense, can be replicated, and can provide predictions.
  4. In Science peer review cancels individual biases. Sadly the current pterosaur referees, Hone, Witton, Naish and others, are all from the same school of thought. Every day I hope to change that, to open them up to accept more valid hypotheses that work!
  5. In Science, if you’re not pssing people off, you’re not doing it right. Well, I must be doing something right, because Witton and Naish are never praising my work. It would be great if we could argue about it. I guess we’re doing that here.

Prothero finished with a cartoon
of a professor who was showing his cognitive dissonance: “If P is false, I will be sad. I do not wish to to be sad. Therefore, P is true.”

This is human nature.
We all have it. We all get jealous, ambitious. disappointed. As scientists we have to get over our human nature and let testing and experimentation rise above human nature. We have to be like Galileo, not Aristotle.

References
Bennett SC 1995. A statistical study of Rhamphorhynchus from the Solnhofen limestone of Germany: year classes of a single large species. Journal of Paleontology 69, 569–580.
Lü J, Unwin DM, Jin X, Liu Y and Ji Q 2009. Evidence for modular evolution in a long-tailed pterosaur with a pterodactyloid skull. Proceedings of the Royal Society London B  (DOI 10.1098/rspb.2009.1603.)
Padian K 1983. Osteology and functional morphology of Dimorphodon macronyx (Buckland) (Pterosauria: Rhamphorhynchoidea) based on new material in the Yale Peabody Museum, Postilla, 189: 1-44.
Peters D 2000. A Redescription of Four Prolacertiform Genera and Implications for Pterosaur Phylogenesis. Rivista Italiana di Paleontologia e Stratigrafia 106 (3): 293–336.
Peters D 2007. The origin and radiation of the Pterosauria. Flugsaurier. The Wellnhofer Pterosaur Meeting, Munich 27
Wang X, Kellner AWA, Jiang S, Meng X. 2009. An unusual long-tailed pterosaur with elongated neck from western Liaoning of China. Anais da Academia Brasileira de Ciências 81 (4): 793–812.

Jianchangopterus – a very ‘rhamphy’ pterodactylid

Jianchangopterus zhaoinanus (Li and Bo 2011, YHK-0931) is a small, complete and crushed Middle Jurassic pterosaur from Liaoning, China. Originally it was described as a scaphognathine pterosaur (Fig. 1) close to Sordes. At first glance, it might be appear to be one. It had short legs, short hands, a longish tail and sharp teeth. What it doesn’t have is a distinct primary naris with a strong maxillary ascending process. So, this is could be VERY interesting, with a little bit of this, and a little bit of that…

So what is it?
An example of modular evolution?

No. 
Modular evolution doesn’t happen. Phylogenetic analysis sorts these sorts of things out. Evolution changes every part of the body, even if just a little bit.

A transitional taxon?
Well, every pterosaur, except terminal taxa, can be considered transitional between its ancestral and derived kin. But in this case Jianchangopterus is not transitional between rhamphs and pterodacs.

Figure 1. Jianchangopterus in situ. It is small, has a long tail, but it nests at the base of the Pterodactylus clade, between Ningchengopterus and the Painten pterosaur, neither of which expose the mid to distal tail. Figure 1. Jianchangopterus in situ. It is small, has a long tail, but it nests at the base of the Pterodactylus clade, between Ningchengopterus and the Painten pterosaur, neither of which exposes the mid to distal tail.

Figure 1. Jianchangopterus in situ, both plates superimposed. It is small, has a long tail, but it nests at the base of the Pterodactylus clade, between Ningchengopterus and the Painten pterosaur, neither of which expose the mid to distal tail. Manual 4.4 is very thin, folded back against m4.3 here in one wing, less folded on the other wing.

What analysis recovers
when you add this taxon to the large pterosaur tree, you find that Jianchangopterus nests between Ningchengopterus and the Painten pterosaur, in their own clade at the base of the genus clade Pterodactylus (Fig. 2). Outgroups to these two clades include Ornithocephalus and two tiny Solnhofen pterosaurs (n9 and n31). The outgroup to all three clades is SMNS81775, a very tiny pterosaur, that I know from a skull drawing only. It has a large orbit, short rostrum and short antorbital fenestra.

Let’s delete all Pterodactylus to see what happens
And the outgroups too. Results: Jianchangopterus nests in the same spot. It doesn’t shift toward any scaphognathines.

Sometimes what is obvious STILL needs to be examined
Lu and Bo looked at certain obvious traits in Jianchangopterus (tail, metacarpus, tooth number, etc.) and decided it was closest to Sordes, which they considered a scaphognathid. It is not. And neither is Jianchangopterus. Shifting Jianchangopterus to Sordes adds 40 steps to the most parsimonious score. Eyeballing a specimen, even following ‘the rules’ regarding certain traits still takes a back seat to phylogenetic analysis.

It’s all in the details…
and the taxa one includes, as I’ve harped on constantly.  On that point, Lu and Bo were not aware of the Painten pterosaur when they published. And they failed to mention Ningchengopterus.

Figure 2. Jianchangopterus between Ningchengopterus and the Painten pterosaur. Note in Jianchangopterus the metacarpus is relatively shorter, especially relative to the ulna. The cervicals are more robust and relatively a little shorter. This is a reversal that makes Jianchangopterus more rhamph-like. You can't eyeball these things. You have to let the matrix and computer recover the relationships.

Figure 2. Jianchangopterus between Ningchengopterus and the Painten pterosaur. Yes, it looks superficially like a basal “rhamph.” But phylogenetic analysis separates the homoplasies from the homologies. Note in Jianchangopterus the metacarpus is relatively shorter, especially relative to the ulna. The cervicals are more robust and relatively a little shorter. This is a reversal that makes Jianchangopterus more rhamph-like. You can’t eyeball these things. You have to let the matrix and computer recover the relationships.

So what about that long tail?
Neither Ningchengopterus nor the Painten pterosaur expose a long tail, either because the plate is broken or the tail is beneath matrix. The outgroups all have a long tail. They also have a longer metacarpus especially relative to the ulna. This is evolution at its best. Nothing proceeds in a straight line. At every generation some are taller, some have longer hands, others have shorter hands.

Figure x. When you compare the three specimens of Sordes to the three jianchangopterids the purported similarities to Sordes start to fade. Shifting Jianchangopterus to Sordes adds 40 steps.

Figure 3. When you compare the three specimens of Sordes to the three jianchangopterids the purported similarities to Sordes start to fade. Shifting Jianchangopterus to Sordes adds 40 steps. The 36 specimen of Sordes nests closer to the Donau Dorygnathus than to the other two Sordes specimens which were themselves basal to Dorygnathus.

 

What about the most basal Pterodactylus?
Here the more derived AMNH1942 specimen of Pterodactylus (n20 in the Wellnhofer 1970 catalog. Fig. 3), the most basal taxon in the Pterodactylus genus clade, also seems to have a very long, but faint tail, largely hidden below a dusting of matrix.

Figure 3. Pterodactylus AMNH1942 with tail traced.

Figure 3. Pterodactylus AMNH1942 with tail traced. Note the tail goes below the leg at the knee, then reappears near the wingtips and trails toward the feet. The matrix itself is filled with organic shapes and what appears to be a tail could be one of these. However, the undisputed long tail of Jianchangopterus adds credence to this interpretation.

Clearly  a robust tail disappears beneath the femur. What we see of the rest of the tail could be organic shapes, which are also all around the matrix. But then with a sister taxon like Jianchangopterus with an undisputed long tail, this deserves further investigation.

Figure 5. Pterodactylus AMNH1942 without the tracing.

Figure 5. Pterodactylus AMNH1942 without the tracing. No doubt the tail disappears behind the femur. Further investigation is needed to find the rest of the tail and expose it on the surface.

More derived Pterodactylus specimens had a short tail.  No doubt about that.
So the tail became further reduced in derived members of this clade. There has been a long-standing assumption that Pterodactylus had a short tail. That assumption really has to be tested by exposing that last caudal vertebra. That hasn’t always (has never) been done. So we might be living under a false paradigm. Jianchangopterus provies a clear clue that the old paradigm needs to be examined in greater detail and with greater certainty.

The short hand
The metacarpus/ulna ratio is very small/short in Jianchangopterus. Phylogenetic analysis demonstrates that this single trait is a reversal from a larger ratio. Don’t think it can’t happen. Evolution works the way it works, and not always in a straight line.

Transitional taxa
We’ve seen several contenders for the transition taxon between rhamphs and pterodacs.

Darwinopterus had a short hand and long tail, but a long skull and neck, but it nests on the rhamph side not anywhere near any of the four pterodac origin/transition points.

Rhamphodactylushad a long skull, short tail and long hands. It nests on the pterodac side of one divide.

Kryptodrakon was a misread large but gracile dorygnathid.

Only the tiny Solnhofen pterosaurs provide concrete evidence for four gradual transitions, each to their own pattern.

Getting back to Jianchangopterus
Lü and Bo report, “the lateral surface of the premaxilla and maxilla have horizontal laminations.” This is what I’ve been reporting, this is the anterior jugal laminated to these underlying bones.

Lü and Bo report, “the maxilla bears a distinct recess (representing the antorbital fossa).” This may not be true. IMHO, what Lu and Bo see is IMHO is a medial sheet of bone dividing the left and right rostra, common to many pterosaurs.

The long tail, clearly laid out on this specimen, takes one positive step to confirm my earlier observations of similar longish, very thin tails on other pterodactyloid-grade pterosaurs.

Reference
Lü J and Bo X 2011. “A New Rhamphorhynchid Pterosaur (Pterosauria) from the Middle Jurassic Tiaojishan Formation of Western Liaoning, China”. Acta Geologica Sinica85(5):977–983.

New basal pterodactyloid(?) Kryptodrakon = Sericipterus, a dorygnathid

The big news this morning:
Andres, Clark and Xu (2014) have claimed to discover the earliest known pterodactyloid (Middle/Late Jurassic, Shishugou Formation in Xinjiang, China).They wrote: “We report here the earliest pterosaur with the diagnostic elongate metacarpus of the Pterodactyloidea, Kryptodrakon progenitor, gen. et sp. nov., from the terrestrial Middle-Upper Jurassic boundary of Northwest China. Phylogenetic analysis confirms this species as the basalmost pterodactyloid.”

Andres reported, “In paleontology, we love to find the earliest members of any group because we can look at them and figure out what they had that made the group so successful.” 

If it is one, it’s a big one!
Wingspan estimates are over a meter.

That big size is the red flag
Of course, this flies in the face of the large pterosaur tree, which recovered four origins for pterodactyloid-grade pterosaurs at about this same time, and they were all tiny. Andres, Clark and Xu did not include these tiny pterosaurs in their phylogenetic analysis.

Figure 1. The bits and pieces of Kryptodrakon assembled into a Pterodactylus bauplan, from Andres, Clark and Xu 2014.

Figure 1. The bits and pieces of Kryptodrakon assembled into a Pterodactylus bauplan, from Andres, Clark and Xu 2014.

It’s always difficult to reassemble bits and pieces,
but not impossible. Andres, Clark and Xu did that above (Fig. 1), using a small Pterodactylus as their bauplan or blueprint.

There’s an alternate bauplan available
and it’s also from the same Shishugou Formation. Sericipterus is a very large and gracile dorygnathid (Fig. 2). When you put the bones of Krypodrakon on top of the bauplan for Sericipterus you find a good match.

Figure 2. The bone bits of Kryptodrakon placed on the bauplan of the giant dorygnathid, Sericipeterus, also from the Shishugou Formation. There's a good match here.

Figure 2. Here the bone bits of Kryptodrakon are placed on the bauplan of the giant dorygnathid, Sericipeterus, also from the Shishugou Formation. There’s a good match here. Perhaps Kryptodrakon is a junior synonym for Sericipterus, filling in some of its missing pieces.

And suddenly that “long metacarpus” is not so long anymore. Notably, Sericipterus had gracile wing bones, and that proved confusing to Andres, Clark and Xu. “Thinner” can sometimes be confused with “longer” unless you know what the bauplan is.

But wait, there’s more.
Compare the metacarpus of Kryptodrakon with its dorsal rib and the metacarpus doesn’t look so long anymore. The same holds for the distal carpal, scapula, humerus and wing joint scraps. They’re all too big for that metacarpus to be “elongate.”

A more parsimonious solution
Kryptodrakon and Seripterus are both from the same formation. They are the same size, and their bones have the same shape (so far as can be told from available scraps). We also know from a larger phylogenetic analysis that includes tiny pterosaurs that basal pterodactyloid-grade pterosaurs were all tiny and Kryptodrakon was big.

Therefore,
the more parsimonious solution is to consider Kryptodrakon a junior synonym for Sericipterus, a giant dorygnathid, not a pterodactyloid.

One more thing
Andres, Clark and Xu were also the discoverers and authors of Sercipterus, the only other pterosaur found in the Shishugou Formation.

Sorry to throw cold water on this.
But testing for parsimony is good Science.

References
Andres B, Clark JM and Xu X 2010.A new rhamphorhynchid pterosaur from the Upper Jurassic of Xinjiang, China, and the phylogenetic relationships of basal pterosaurs, Journal of Vertebrate Paleontology 30: (1) 163-187.
Andres B, Clark J and Xu X 2014. The Earliest Pterodactyloid and the Origin of the Group. Current Biology (advance online publication)
DOI: http://dx.doi.org/10.1016/j.cub.2014.03.030

Read more: Science_News