Cawley et al. 2020 did not realize Mesozoic pycnodonts were derived from extant bonefish

Cawley et al. 2020
brought us an overview of a clade of Mesozoic fish, the Pycnodontiformes (Fig. 1).

From the abstract
“Two other neopterygian clades possessing similar ecological adaptations in both body morphology (†Dapediiformes) and dentition (Ginglymodi) also occurred in Mesozoic seas.”

Short note: Dapediformes includes Dapedium and kin (taxa related to gars, like Lepisosteus in the LRT). Ginglymodi includes Semionotiformes (Semionnotus) and Lepidotidae (Lepidotes and Lepisosteus (= gars)). These taxa nest basal to catfish + placoderms in the LRT. They are Silurian in origin, not related to Pycnodus (Fig. 2) and Albula (Figs. 1, 3) in the LRT.

From the introduction:
“The overarching goal of this study is to evaluate the success but also final demise of pycnodontiform fishes, which represented the major marine actinopterygian elements from the Late Triassic to Palaeogene.”

Figure 1. Color image from Cawley et al. 2020. Albula added. Taxa below the gray line are Semionotiformes unrelated to pycnodontiformes.

Figure 1. Color image from Cawley et al. 2020. Albula added. Taxa below the gray line are Semionotiformes unrelated to pycnodontiformes.

Unfortunately Cawley et al. fails to mention
the extant pycnodontiform, the bonefish, Albula, which nests with the pycnodontiforms, Flagellipinna and Pycnodus (Agassiz 1835), in the large reptile tree (LRT, 1804+ taxa).

Also unfortunately,
Cawley et al. inappropriately includes several members of the Dapediidae and Semionotiformes (Fig. 1). Due to taxon exclusion the authors don’t realize these taxa nest in the other major clade of bony fish, apart from most ray fins, closer to spiny sharks, placoderms and lobefins, far from Pycnodus and Albula.

Cawley et al. reports, 
“Pycnodontiforms represent a well-defined monophyletic group…”

then admits,
“but the intrarelationships of various taxa and groups remain debated.” The LRT tests virtually all other fish clades.

Figure 2. Pycnodus with bones colorized according to tetrapod homologies. Third frame shows maxilla and lacrimal returned to in vivo positions.

Figure 2. Pycnodus with bones colorized according to tetrapod homologies. Third frame shows maxilla and lacrimal returned to in vivo positions.

Wikipedia reports,
Pycnodontiformes is an extinct order of bony fish. The group evolved during the Late Triassic and disappeared during the Eocene. The group has been found in rock formations in Africa, Asia, Europe, North and South America. The pycnodontiforms were small to middle-sized fish, with laterally-compressed body and almost circular outline. Pycnodontiform fishes lived mostly in shallow-water seas. They had special jaws with round and flattened teeth, well adapted to crush food items. One study links the dentine tubules in pycnodont teeth to comparable structures in the dermal denticles of early Paleozoic fish. Some species lived in rivers and possibly fed on molluscs and crustaceans.”

Figure 1. Albula vulpes skull with highly derived facial bones reidentified here. Note the lateral premaxillary processes and 'floating' cheek bones. Green vertebrae are caudals.

Figure 3. Albula vulpes skull with highly derived facial bones reidentified here. Note the lateral premaxillary processes and ‘floating’ cheek bones. Green vertebrae are caudals.

Pycnodus according to Wikipedia
“The known whole fossils of Pycnodus are around 12 centimetres (5 in) long, and have a superficial resemblance to angelfish or butterflyfish. The animals, as typical of all other pycnodontids, had many knob-like teeth, forming pavements in the jaws with which to break and crush hard food substances, probably mollusks and echinoderms. These teeth are the most common form of fossil.”

According to Wikipedia
Bonefishes live in inshore tropical waters and moves onto shallow mudflats or sand flats to feed with the incoming tide. The bonefish feeds on benthic worms, fry, crustaceans, and mollusks. Ledges, drop-offs, and clean, healthy seagrass beds yield abundant small prey such as crabs and shrimp. It may follow stingrays to catch the small animals they root from the substrate.”

Apparently no one has reported
that pycnodontiformes is an extinct clade within the extant clade Albulidae. Likewise no one has reported that Semionotifomes are not related to Pycnodontiformes. If so, please send the citation so I can promote it here.


References
Agassiz JLR 1835.Recherches sur les Poissons fossiles, 5 volumes. Imprimerie de Petitpierre et Prince, Neuchaatel, 1420 pp.
Bleeker P 1859. xx
Cawley JJ et al. (5 co-authors) 2020.
Rise and fall of Pycnodontiformes: Diversity, competition and extinction of a successful fish clade. Ecology and evolution DOI: 10.1002/ece3.7168

wiki/Pycnodontiformes
wiki/Pycnodus
wiki/Bonefish

Pycnodontiformes Berg 1937
Albulidae Bleeer 1859

 

Agnolin 2021 on Brontornis affinities (still excluding parrots and stinkbirds)

Yes, it’s massive taxon exclusion time again
as Agnolin 2021 tells us that Brontornis (Fig. 2) is a giant goose.

We’ve known since 2011
that Brontornis is closely related to Gastornis (Figs. 1, 2) the giant flightless parrot.  Derived from hoatzins first, then sparrows, then even more distantly from fowl (= chickens, pheasants, peacocks), these giant flightless, herbivorous birds have all the hallmarks (= characters) of Ara, the parrot (Fig. 1).

Unfortunately,
these taxa were excluded from Agnolin’s 2021 analysis, again.

Figure 1. Gastornis (=Diatryma) to scale with Ara the parrot (lower right).

Figure 1. Gastornis (=Diatryma) to scale with Ara the parrot (lower right).

Figure 3. Skulls of Gastornis, Brontornis and Ara, the scarlet macaw.

Figure 3. Skulls of Gastornis, Brontornis and Ara, the scarlet macaw.

Agnolin 2007
also considered Brontornis a giant goose (Anseriformes).

Agnolin 2021
wrote, “After few changes in the data matrix, Brontornis results as part of a clade composed by the giant anseriforms designated by Worthy et al. 2017 as Gastornithiformes. This result is in agreement with recent proposals that excluded Brontornis from phorusrhacoid cariamiforms (where it was traditionally nested) and included it among Anseriformes.”

“Finally, the nesting of Brontornis among herbivorous giant anseriforms, together with several aspects of its mandibular morphology reinforces previous thoughts that Brontornis was herbivorous in habits.”

Fowl, sparrows, hoatzin (= stinkbirds) and parrots are all also herbivorous.

Unfortunately Agnolin 2007, 2021 supports
the hypothesis that fowl and geese are closely related in a traditional genomic clade, Galloanseriformes (= chicken + geese). The large reptile tree (LRT, 1803+ taxa; subset Fig. x) does not support that relationship. Rather fowl and geese are widely separated in the LRT where fowl are in cyan (= bright light blue, Fig. x) and geese are in pale magenta (= pinkish purple Fig. x).

Figure 4. Subset of the LRT focusing on birds. Chongmingia is highlighted in yellow in the Scansoriopterygidae.

Figure 4. Subset of the LRT focusing on birds. Chongmingia is highlighted in yellow in the Scansoriopterygidae.

Taxon exclusion
will always come back to haunt/bite you (pick your own favorite cliché). Add taxa as a remedy for this malady. It works every time.


References
Agnolin F 2007. Brontornis burmeisteri Moreno & Mercerat, un Anseriformes (Aves) gigante del Mioceno Medio de Patagonia, Argentina. Revista del Museo Argentino de Ciencias Naturales, n.s.9, 15-25.
Agnolin F 2021. Reappraisal on the Phylogenetic Relationships of the Enigmatic Flightless Bird (Brontornis burmeisteri) Moreno and Mercerat, 1891. Diversity 2021, 13, 90. https://doi.org/10.3390/d13020090
Andors AV 1992. Reappraisal of the Eocene ground bird Diatryma (Aves: Anserimorphae). Science Series Natural History Museum of Los Angeles County. 36: 109–125.
Bourdon E and Cracraft J 2011. Gastornis is a terror bird: New insights into the evolution of the cariamae (Aves, Neornithes). Society of Vertebrate Paleontology 71stAnnual Meeting Program and Abstracts, p. 75
Buffetaut E 2014. Tertiary ground birds from Patagonia (Argentina) in the Tournouër collection of the Muséum National d’Histoire Naturelle, Paris. Bulletin de la Société Géologique de France. 185(3):207–214.
Cope ED 1876. On a gigantic bird from the Eocene of New Mexico. Proceedings of the Academy of Natural Sciences of Philadelphia 28 (2): 10–11.
Hackett S et al. 2008. A phylogenetic study of birds reveals their evolutionary history. Science 320:1763–1768.
Hébert E 1855a. Note sur le tibia du Gastornis pariensis [sic] [Note on the tibia of G. parisiensis]. C. R. Hebd. Acad. Sci. Paris (in French) 40: 579–582.
Hébert E 1855b. Note sur le fémur du Gastornis parisiensis [Note on the femur of G. parisiensis]. C. R. Hebd. Acad. Sci. Paris (in French) 40: 1214–1217.
Linnaeus C 1758. Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata.
Matthew WD, Granger W and Stein W 1917. The skeleton of Diatryma, a gigantic bird from the Lower Eocene of Wyoming. Buletin of the American Museum of Natural History, 37(11): 307-354.
Mustoe GE, Tucker DS and Kemplin KL 2012. Giant Eocene bird footprints from northwest Washington, USA. Palaeontology. 55 (6): 1293–1305.
Owen R 1843. On the remains of Dinornis, an extinct gigantic struthious bird. Proceedings of the Zoological Society of London: 8–10, 144–146.
Prévost C 1855. Annonce de la découverte d’un oiseau fossile de taille gigantesque, trouvé à la partie inférieure de l’argile plastique des terrains parisiens [Announcement of the discovery of a fossil bird of gigantic size, found in the lower Argile Plastique formation of the Paris region]. C. R. Hebd. Acad. Sci. Paris (in French) 40: 554–557.
Prum RO et al. (6 co-authors) 2015. A comprehensive phylogeny of birds (Aves) using targeted next-generation DNA sequencing. Nature doi:10.1038/nature15697
Witmer L and Rose K 1991. Biomechanics of the jaw apparatus of the gigantic Eocene bird Diatryma: Implications for diet and mode of life. Paleobiology. 17 (2): 95–120.
Worthy TH, Degrange FJ, Handley WD and Lee MSY 2017. The evolution of giant flightless birds and novel phylogenetic relationships for extinct fowl (Aves, Galloanseres). Royal Society Open Science 4: 170975. http://dx.doi.org/10.1098/rsos.170975
Wright TF, et al. (ten co-authors) 2008. A Multilocus Molecular Phylogeny of the Parrots (Psittaciformes): Support for a Gondwanan Origin during the Cretaceous. Molecular Biology and Evolution, 25 (10), 2141-2156 DOI: 10.1093/molbev/msn160.

https://pterosaurheresies.wordpress.com/2017/11/06/the-origin-of-giant-birds-gastornis-diatryma-the-giant-parrot/

https://pterosaurheresies.wordpress.com/2017/09/15/lrt-sheds-light-on-gastornis-its-a-giant-flightless-parrot/

 

Archelon enters the LRT with snapping turtles

This post was set in motion by a recent PBS Eons YouTube video
all about the biggest fossil turtle ever described, Archelon (Figs. 1, 2). Click to play.

The narrator reported
that Archelon (Figs. 1, 2) was not related to living sea turtles, not even to Dermochelys, the living leatherback (Fig. 4). Well that mystery sounds like a job for the LRT. Maybe it can do some good. And it’s good to get back to reptiles for an evening. It’s been awhile…

Figure 1. Classic photos of Archelon in ventral and dorsal views.

Figure 1. Classic photos of Archelon in ventral and dorsal views.

After testing
in the large reptile tree (LRT, 1802+ taxa) Archelon (Figs. 1, 2) nests firmly with Macrochelys, the alligator snapping turtle (Fig. 3). That’s why Archelon is not related to living sea turtles and perhaps why it’s terrestrial origin has remained a mystery until now.

Once again, testing taxa together that have never been tested together before sometimes recovers such unexpected, but inevitable results.

When you see the skulls together
(Figs. 2, 3), the relationship seems obvious. Most turtles do not extend their premaxilla like a hawk beak, but Archelon and snapping turtles do. The skull suture patterns are also distinct from other turtles and shared between only these two of all other turtles tested in the LRT.

Figure 2. Skull of Archelon with colors identifying bones. Compare to Macrochelys in figure 3.

Figure 2. Skull of Archelon with colors identifying bones. Compare to Macrochelys in figure 3.

In the ancient and dangerous Niobrara Sea covering much of North America,
it took a giant, mean-old snapping turtle with flippers to survive in a seaway full of other giant monster reptiles.

Figure 3. Macrochelys skull in three views with colors added to bones. Compare to Archelon in figure 2.

Figure 3. Macrochelys skull in three views with colors added to bones. Compare to Archelon in figure 2. Image from Catalogue of shield reptiles in the collection of the British Museum.

Archelon ischyros
 (Wieland 1896; Late Cretaceous; 4.6m or 15 feet in length; Figs 1,2) is the largest turtle ever documented. Along with ProtostegusArchelon is traditionally considered a member of the Protostegidae. In the LRT Archelon nests with Macrochelys, the alligator snapping turtle (Fig. 3). Distinct from Macrochelys, the naris opens dorsally in Archelon.

Figure 4. Macrochelys skeleton documenting the origin of the open ribs with small fenestrations.

Figure 4. Macrochelys skeleton documenting the origin of the open ribs with small fenestrations.

Archelon is distinct from and parrallel to
other sea turtles, all of which have a shorter, transverse premaxilla and different skull bone patterns (e.g. Fig. 4). Previous workers had already removed protostegids from other sea turtles, but then stopped there. The Archelon relationship to snapping turtles was not tested or known until now. If proposed previously, please send a citation so I can promote it here.

A leathery carapace,
like that of Dermochelys, covered the similarly open ribs of Archelon (Fig. 1), but the two tax are not related. Dermochelys is closer to sea turtles with a traditional hard-shelled carapace.

Figure 4. Skulls of Dermochelys, the extant leatherback turtle. The skull pattern here is distinct from patterns in Archelon and other snapping turtles (above).

Figure 4. Skulls of Dermochelys, the extant leatherback turtle. The skull pattern here is distinct from patterns in Archelon and other snapping turtles (above).

Not sure why snapping turtles and Archelon 
were never shown to be related to one another before. It seems obvious in hindsight. This struck me as low-hanging fruit left by PhDs for armchair amateurs to deduce. It just took one evening to nest this enigma. Let me know if there are any more enigmas lurking out there that need a good nesting. This is the fun part.

Postscript Feb. 19, 2021
Readers have reported that I might have colorized osteoderms or scales instead of bone sutures. Jura sent the images on the left, which I desaturated and burned to bring out details. Those seem to show scalation. The colored images appear to show sutures. Right? Or wrong?

Jura replied: top = sutures, bottom = welded osteoderms. Compare the top image with figure 4 from Sheil 2005′

The Shiel 2005 image of Macrochelys (= Macroclemys) is a diagram drawing from Gaffney 1979. The Gaffney 1979 image is a diagram drawing from Gaffney 1975e.

Figure x. Osteoderms on the left don't always align with bones on the right in these images of Macrochelys.

Figure x. Osteoderms on the left don’t always align with bones on the right in these images of Macrochelys.

Figure y. Macrochelys skull with traditional labels (b&w) and LRT labels (color). The LRT prefrontal rims the orbit, as in all other tetrapods.

Figure y. Macrochelys skull with traditional labels (b&w) and LRT labels (color). The LRT prefrontal rims the orbit, as in all other tetrapods.

It seems to me,
and let me know if this is an error, that everybody recognizes the pair of bones over the naris. Traditionally these are labeled prefrontals (Fig. y), even though they don’t touch the orbit. Other bones have different traditional labels, too. My labels come from pareiasaur and Elginia homologs so those labels come from a valid phylogenetic context. Traditional labels are wrong because the pareiasaur ancestry is not yet widely, if at all, recognized. All other turtle ancestor candidates are tested in the LRT.


References
Gaffney ES 1975e. Phylogeny of the chelydrid turtles: a study of shared derived characters in the skull. Fieldiana:Geol., vol. 33, pp. 157-178.
Gaffney ES 1979. Comparative cranial morphology of recent and fossil turtles. Bulletin of the American Museum of Natural History 164(2):65–376.
Sheil CA 2005. Skeletal development of Macrochelys terrminckii (Reptilia: Testudines: Chelydridae) Journal of Morphology 263:71–106.
Wieland GR 1896. Archelon ischyros: a new gigantic cryptodire testudinate from the Fort Pierre Cretaceous of South Dakota. American Journal of Science. 4th series. 2 (12): 399–412.

wiki/Macrochelys
wiki/Archelon

 

How the shark lost its bones video on YouTube

From Martin Brazeau and the Imperial College London,
here’s a new YouTube video (53 minutes) on how and maybe why sharks lost their bony exoskeleton.

The phylogenetic context is wrong. Without testing, Brazeau et al. considered placoderms basal to sharks and bony fish.That’s a traditional mistake. In the large reptile tree (LRT, 1795+ taxa) placoderms are bony fish close to catfish. In the LRT sharks evolved from sturgeons (Fig. 2). Bony fish evolved from hybodontid sharks. The Silurian is when all this happened.

We looked at this subject earlier here (Borrell 2014) and here Brazeau et al. 2020.

Unfortunately, as you’ll see
Brazeau et al. include only fossil taxa to determine which taxa were present in the Silurian.

Figure x. Shark skull evolution.

The jawless,
(by reversal) anapsid-mimic placoderm, Minjinia (Fig. 3) was featured in Brazeau’s paper and video.

Figure 1. Subset of the LRT focusing on the branch of the Osteichthys that includes placoderms and their relatives.
Figure 2. Subset of the LRT focusing on the branch of the Osteichthys that includes placoderms and their relatives.
Figure 1. Minjina in 4 views, mirror-image and colors added.
Figure 1. Minjina in 4 views, mirror-image and colors added.

Ironically
Brazeau illustrates his talk with an image of the exoskeleton and endoskeleton of the sturgeon Acipenser. which entered the LRT here. He reports the endochondral bone was lost in sturgeons. That is a traditional mistake as revealed by the LRT.

Brazeau correctly reports
the origin of bone precedes sharks and is lost in sharks. He just did not realize that placoderms are descendants of sharks, not their ancestors.


References
Brazeau et al. (7 co-authors) 2020. Endochondral bone in an Early Devonian ‘placoderm’ from Mongolia. Nature Ecology & Evolution. https://doi.org/10.1038/s41559-020-01290-2
Hu Y, Lu J and Young GC 2017. New findings in a 400 million-year-old Devonian placoderm shed light on jaw structure and function in basal gnathostomes. Nature Scientific Reports 7: 7813 DOI:10.1038/s41598-017-07674-y

https://cosmosmagazine.com/nature/evolution/new-thoughts-on-how-sharks-evolved/http://www.sci-news.com/paleontology/minjinia-turgenensis-08823.html

A giant Eocene whale from Ukraine

Davydenko et al. 2021
report the discovery of new giant basilosaurid from Ukraine.

From the abstract:
“The earliest fully aquatic cetaceans arose during the Middle Eocene; however, the earliest stage of their divergence is obscure. Here, we provide a detailed redescription of an unusual early cetacean, “Platyosphys einori”, from the Late Eocene of Ukraine (37.8–35.8 million years ago), with new data on its body size, skeletal microanatomy and suggestions on phylogenetic relationships.”

By contrast, in the large reptile tree (LRT, 1793+ taxa) the earliest stage of ‘their divergence’ (mysticetes and odontocetes) extends back to tiny tree shrews in the Jurassic. Contra public and professional opinion, whale divergence is not obscure. Taxon exclusion hampers the Davydenko et al. study.

Figure 1. Cladogram from Davydenko et al. 2021 showing how they nested Playosphys einori. See figure 2 for their proposed mysticetes (with teeth!)

Figure 1. Cladogram from Davydenko et al. 2021 showing how they nested Playosphys einori. See figure 2 for their proposed mysticetes (with teeth!)

Unfortunately the authors presented an outdated cladogram
that considered the former clade ‘Cetacea’ monophyletic. Their paper perpetuates an invalid hypothesis of interrelationships (Figs. 1,2) that omits the ancestors of mysticetes: desmostylians, anthracubunids, hippos, mesonychids and oreodonts. They also omit the ancestors of pakicetids: tenrecs and anagalids.

Figure 2. Portion of the cladogram from figure 1 enlarged and rotated. Llancetus and kin are not mysticete ancestors when more taxa, like Behemotops, are included in the analysis.

Figure 2. Portion of the cladogram from figure 1 enlarged and rotated. Llancetus and kin are not mysticete ancestors when more taxa, like Behemotops, are included in the analysis.

Sadly,
whale workers continue to perpetuate the myth that whales are monophyletic. That was invalidated several years ago here by simply adding taxa.


References
Davydenko S, Shevchenko T, Ryabokon T. et al. 2021. A Giant Eocene Whale from Ukraine Uncovers Early Cetacean Adaptations to the Fully Aquatic Life. Evol Biol (2021). https://doi.org/10.1007/s11692-020-09524-8

researchgate.net/publication/328388746_The_triple_origin_of_whales

reptileevolution.com/reptile-tree.htm

Degrange 2021 revises Phorusrhacidae

From the Degrange 2021 abstract
“Phorusrhacidae, popularly known as ‘terror birds’, are the most speciose clade within the avian order Cariamiformes, with a fossil record that ranges from the Eocene to the Pleistocene. Although several species have preserved skulls, our understanding of their cranial morphology remains incomplete. Here, a comprehensive overview of the current knowledge of phorusrhacid skull anatomy is presented.”

Some phylogenetic issues here due to taxon exclusion.

Figure 1. Cariama and Sagittarius. The former is a sister to flamingoes. The latter is a sister to the terror birds in the LRT.

Figure 1. Cariama and Sagittarius. The former is a sister to flamingoes. The latter is a sister to the terror birds in the LRT.

Unfortunately,
Degrange 2021 nests terror birds within the clade Cariamiformes, which include Cariama (Fig. 1) , the sister to Phoenicopterus, the flamingo in the large reptile tree (LRT, 1793+ taxa). By adding taxa, rather than relying on outdated tradition, Degrange should have nested phorusrhacids withe the secretary bird, Sagittarius (Fig. 1), the sister to phorusrhachids in the LRT. We looked at this taxonomic problem in September 2017. and again in November 2017.

Figure 1. Phorushacids to scale. The extant Sagittarius is in color at lower right.

Figure 2. Phorushacids to scale. The extant Sagittarius is in color at lower right.

According to Wikipedia,
“Molecular phylogenetic studies have shown that Cariamiformes is basal to the Falconiformes, Psittaciformes and Passeriformes” 

In the LRT Cariama and Sagittarius are basal to nearly all non-ratite birds. The above list omits galliformes (Gallus), which nest between falconiformes (Falco) and passeriformes (Passer) in the LRT.

Figure 1. Phorusrhacos to scale with Dinornis, Struthio and Homo.

Figure 3. Phorusrhacos to scale with Dinornis, Struthio and Homo.

Once again,
adding taxa while avoiding molecular studies and outdated traditions recovers a cladogram in which gradual evolution is demonstrated at every node.


References
Degrange FJ 2021. A Revision of Skull Morphology In Phorusrhacidae (Aves, Cariamiformes) Journal of Vertebrate Paleontology Article: e1848855
DOI: 10.1080/02724634.2020.1848855

https://www.tandfonline.com/doi/full/10.1080/02724634.2020.1848855

 

Correction: European eels are neotonous swordfish

Before you say, “That’s crazy!” did you ever notice
that swordfish lack ribs and pelvic fins (Fig. 4)? So do European eels.

More importantly, did you ever notice
that baby swordfish look like eels (Fig. 4)? Okay. With that in mind, let’s start with a little backstory and cover all the bases.

Traditionally swordfish have been allied with 
barracuda, marlin and several extinct billfish, including Blochideae (i.e. Blochius, Fig. 4), based on overall appearance, open sea niche and apex predator status. According to Wikipedia, “They [swordfish] are the sole member of their family, Xiphiidae.” Gregory and Conrad  1937 compared the morphologies of the sailfish and swordfish. Earlier I followed the lead of these experts in nesting the sailfish, Istiophorus (Figs. 5, 7), and the swordfish, Xiphiias, with the barracuda, Sphyraena. That was a mistake.

Today we’ll compare
swordfish and sailfish morphology to two other more closely related taxa: the anchovy, Elops (Fig. 6) and the European eel, Anguilla, which turns out to be more closely related to swordfish despite their outward differences as adults. Turns out that swordfish go through a metamorphosis as they develop from eel-like hatchlings with teeth (Fig. 4).

The LRT scores skeletal traits 
rather than superficial morphologies, which are always prone to reversal and convergence. The large reptile tree (1793+ taxa) is designed to test taxa together that have not been tested together before. Some surprises were recovered earlier using this method here, here and here.

In their description of Bavarichthys
(Fig. 1) Arratia and Tischlinger 2010 did not mention or test the eel, Anguilla, or the swordfish, Xiphias. Turns out, they should have done so.

Recent revisions
of several fish taxa (now that I have 250 fish taxa and the experience that brings to bear) reveal a hitherto overlooked hypothesis of interrelationships between eels and swordfish. Sound crazy? Keep reading. This is one of those ‘moment of discovery’ moments I want to share with you.

Figure 1. Bavarichthys is a big head/ short body anchovy from the Late Jurassic. Now it is ancestral to European eels.

Figure 1. Bavarichthys is a big head/ short body anchovy from the Late Jurassic. Now it is ancestral to European eels.

Let the cheek plates evolve away in Bavarichthys
(Fig. 1) and you’l have the basic skull of both swordfish (Fig. 2) and European eels (Fig. 3). Note the triangular profile, the slender insertion of the nasal between the anterior frontals, the extreme brevity of the post-orbital portion of the skull, including a vertical quadrate. No other tested fish taxa have these traits.

Figure 2. Diagram of the swordfish (Xiphias) skull. Compare to figures 1 and 3.

Figure 2. Diagram of the swordfish (Xiphias) skull. Compare to figures 1 and 3.

Billfish came first. 
The European eel, Anguilla, is derived from swordfish, sailfish and Late Jurassic Bavarichthys. Hatchlings of swordfish are eel-like (Fig. 4) and Bavarichthys-like (Fig. 1). That means European eels are neotonous swordfish. They achieve adulthood while still in the hatchling swordfish stage. European eels also develop traits not found in swordfish, like additional vertebrae and a long, low operculum. European eels don’t develop pelvic fins of dorsal ribs. Neither do swordfish.

Figure 5. Skull of Anguilla, the European eel, compares well with that of Bavarichthys. Note the loss and reduction of preorbital bones.

Figure 3. Skull of Anguilla, the European eel, compares well with that of Bavarichthys. Note the loss and reduction of preorbital bones.

Earlier the LRT nested
Late Jurassic Bavarichthys with closely related anchovies (genus: Elops), then with more closely related European eels (genus: Anguilla). Now it nests basal to both swordfish and European eels.

Other eels,
like the moray eel (Gymnothorax) and electric eel (Electrophorus) nest elsewhere, both near the base of the bony fish. So eels were in the gene pool.

Figure 4. Swordfish ontogeny (growth series). Hatchings have teeth, a short bill and an eel-like body still lacing pelvic fins.

Figure 4. Swordfish ontogeny (growth series). Hatchings have teeth, a short bill and an eel-like body still lacing pelvic fins. Hatchlings go through an eel-like phase and a sailfish-like phase.

Xiphias gladius
(Linneaus 1758; Gregory and Conrad 1937; up to 4.5m in length) is the extant swordfish, nesting between Bavarichthys and Anguilla. 1cm long hatchlings more closely resembled little eels, then growing to little sailfish before reducing the long dorsal fin. The sword is not used to spear, but to slice and maim smaller fish traveling in schools. The pelvic fins and ribs are absent, as in eels. Larger females produce more eggs, up to 29 million.

Figure 5. Skull of the sailfish, Istiophorus. Compare to Elops in figure 6.

Figure 5. Skull of the sailfish, Istiophorus. Compare to Elops in figure 6.

Figure 2. Elops is the extant anchovy. Compare to Bavaricthys in figure 1 and Istiophorus in figure 5.

Figure 6. Elops is the extant anchovy. Compare to Bavaricthys in figure 1 and Istiophorus in figure 5.

Figure 1. Istiophorus, the sailfish, nests with the cobria (Fig. 2) in the LRT, not with the swordfish.

Figure 7. Istiophorus, the sailfish, nests with the anchovy, Elops, not with, but close to the sailfish, Xiphias.

Sailfish have long slender pelvic fins,
like those of anchovies, unlike swordfish and eels. Sailfish have a broad postorbital, like anchovies, unlike swordfish. Sailfish have a zig-zag frontal-nasal suture, like anchovies, unlike swordfish. The list of subtle, but scoreable differences continues. More importantly, no other tested taxa share more traits with swordfish and sailfish than eels and anchovies, respectively.

Figure 8. Subset of the LRT focusing on ray fin fish. Eel-like taxa are highlighted.

Figure 8. Subset of the LRT focusing on ray fin fish. Eel-like taxa are highlighted.

With the sailfish and swordfish gone, where does that leave the lonely barracuda?
In the LRT the barracuda nests with the similar long-bodied remora (Remora) and cobia (Rachycentron), derived from the mahi-mahi (Coryphaena) all with mandibular prognathism. This is non-tradional. Other workers prefer to nest billfish with barracuda.


References
Arratia G and Tischlinger H 2010. The first record of Late Jurassic crossognathiform fishes from Europe and their phylogenetic importance for teleostean phylogeny. Mitteilungen aus dem Museum für Naturkunde in Berlin. Fossil Record; Berlin 13(2): 317–341.
Gregory WK and Conrad GM 1937. The comparative anatomy of the swordfish (Xiphias) and the sailfish (Istiophorus). The American Museum Novitates, 952:1-25.
Linnaeus C von 1758. Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata.

https://pterosaurheresies.wordpress.com/2020/07/04/bavarichthys-a-late-jurassic-solnhofen-anchovy/

wiki/Istiophoriformes

wiki/Swordfish

 

Pol et al. 2021: Anachronistic look at the origin of the Sauropodomorpha

From the Pol et al. 2021 abstract
“Sauropodomorpha is the first major dinosaurian group that radiated during the Triassic.”

No. That’s not how it works in phylogenetic analysis. Clades don’t radiate alone without a second clade also radiating.

Here’s how it works: From a basal clade, llike Dinosauria (represented by Herrerasaurus), there is always a dichotomy where one branch, like Theropoda (represented by Tawa), splits from the another branch, like Phytodinosauria (represented by Buriolestes). This happens in all phylogenetic analyses as it does in the large reptile tree (LRT 1793+ taxa). Rarely three branches arise to produce an unresolved node. That usually means a mistake in scoring. Such a node is not present in this subset  of the LRT focusing on Sauropodomorpha (Fig. 1).

Figure 2. Subset of the LRT focusing on basal phytodinosauria. Aardonyx nests with Saturnalia here.

Figure 1. Subset of the LRT focusing on basal phytodinosauria. Aardonyx nests with Saturnalia here. The Sauropodomorpha is the sister clade to Ornithischia (cropped off the bottom of the graphic).

From the abstract:
“Sauropodomorpha is one of the three major groups of Dinosauria, along with Theropoda and Ornithischia (Benton, 1983; Novas, 1996), and became the most conspicuous herbivores of terrestrial ecosystems of the Mesozoic.”

Again, this is anachronistic paleontology. There are never three major groups of any vertebrate. There should always be dichotomies. Pol et al. need to add taxa to understand the first dichotomy in the Dinosauria splits the Theropoda from the Phytodinosauria. Several nodes later a dichotomy splits Sauropodomorpha from Ornithischia. Both are plant eaters.

Figure 2. Plateosaurus skeleton digitized.

Figure 2. Plateosaurus skeleton digitized.

From the abstract
“These early lineages are currently referred as basal or early sauropodomorphs (Bronzati, 2017) or more traditionally grouped in Prosauropoda (Sereno, 1999; Galton and Upchurch, 2004), a term now in disuse as most phylogenetic studies in the last decade agree in the paraphyly of this group.”

The first dichotomy in Sauropodomorpha in the LRT splits taxa leading to Plateosaurus (Plateosauridae Marsh 1895 = Prosauropoda Huene 1920, Sereno 1998, Fig. 2) from taxa leading to Brachiosaurus.

Recently Baron, Norman and Barrett 2017 were unable to recover basal Phytodinosauria due to taxon exclusion. They also mixed up basal sauropods with basal plateosaurs.

Figure 1. Tiny forelimbs with three sharp-clawed fingers indicate that Guaibasaurus is a theropod, not a sauropodomorph. Shown to scale with related theropods Marasuchus and Procompsognathus.

Figure 3. Tiny forelimbs with three sharp-clawed fingers indicate that Guaibasaurus is a theropod, not a sauropodomorph. Shown to scale with related theropods Marasuchus and Procompsognathus.

Pol et al. report, 
“Guaibasaurus is included in the table although many studies depicted this taxon as an early theropod or saurischian (see text).”

In the LRT Guaibasaurus (Fig. 3) is indeed a basal theropod, so should not have been included in a study focused on phytodinosaurs or sauropodomorphs. That would be like adding pterosaurs to a study focused on archosaurs. Hah! Who would do THAT? (Everyone else, sadly, each time by excluding pertinent taxa).


References
Baron MG, Norman DB and Barrett PM 2017. A new hypothesis of dinosaur relationships and early dinosaur evolution. Nature, 543: 501–506.
Pol D, Otero A, Apaldetti CA and Martinez RJ 2021.
Triassic sauropodomorph dinosaurs from South America: the origin and diversification of dinosaur dominated herbivorous faunas. Journal of South American Earth Sciences. https://doi.org/10.1016/j.jsames.2020.103145

wiki/Plateosauria
https://pterosaurheresies.wordpress.com/2020/11/24/plateosaurus-enters-the-lrt/

The paddlefish (Polyodon) and basking shark (Cetorhinus) are closely related

The ‘key trait’: having one gill cover or several gill covers
(as in sharks, Fig. 1) turns out to be a trivial trait in a matrix of 235 traits in the large reptile tree (= LRT, subset Fig. 2). Only one gene has to change to make one type of gill or the other as recently documented (see below).

Figure 1. The basking shark (Cetorhinus) compared to the paddlefish (Polyodon).
Figure 1. The basking shark (Cetorhinus) compared to the paddlefish (Polyodon). Note the gelatinous rostrum in the paddlefish juvenile. That trait is retained in mako sharks, as we learned earlier.

What does ‘closely related’ actually mean?
No other tested taxon shares as many traits with paddlefish (Polyodon) as the basking shark (Cetorhinus, Fig. 1) in the LRT. Someday a taxon might be added that nests between them. At present such taxa remain unknown and untested. Both taxa are derived from the Polyodon hatchling taxon (Fig. 3), which has a shorter rostrum and a more basking shark-like appearance overall. Back in the Silurian, pre-paddlefish hatchlings were likely much smaller and adults were likely the size of present day hatchlings, but that’s not a requirement. No other analysis that I am aware of has ever included paddlefish hatchlings as taxa, but that morphology is key to understanding various lineages within Chondrichthyes. So, here’s a case where adding a taxon is much more important than adding a character.

Figure 6. Adding Debeerius to the LRT helped revise the shark-subset. Note the shifting of the basking shark, Cetorhnus within the paddlefish clade.
Figure 2. Adding Debeerius to the LRT helped revise the shark-subset. Note the shifting of the basking shark, Cetorhnus within the paddlefish clade.

Note the gelatinous rostrum
in the paddlefish juvenile (Fig. 1). That trait is retained from mako sharks (Figs. 3, 6, as we learned earlier here. The rostrum of the adult basking shark is likewise filled with gelatin supported by a thin frame of cartilage (Fig. 4). The shark-like appearance of paddlefish has been noted previously. Previously the presence of one enormous gill cover in paddlefish has excluded them form prior shark studies. The LRT minimizes such taxon exclusion by simply adding taxa.

We’ve always known
that ratfish (with one gill cover, Fig. 3) nest with sharks (with several gill covers separating slits). No one has complained about that yet.

Then we learned
that sturgeons and Chondrosteus (with one gill cover, Fig. 3) nest basal to whale sharks and mantas (with several gill covers). The pattern of gill covers was presented and revised recently here.

Figure 3. Shark skull evolution according to the LRT. Compare to figure 1.

Now
paddlefish (Polyodon) nests with basking sharks (Cetorhinus, Fig. 1) in the large reptile tree (LRT, 1785+ taxa, subset Fig. 2). Evolution is full of such trivial exceptions.

Paddlefish inhabit rivers. Basking sharks inhabit the sea.
They both feed the same way. Basking sharks reach 30 feet in length. Paddlefish reach 7 feet in length. The two likely went their separate ways in the Silurian (prior to 420mya), so they had plenty of time to evolve on their own since then.

Figure 2. Skull of Cetorhinus adult and juvenile showing differences in the rostrum and fusion of skull elements in the adult.
Figure 4. Skull of Cetorhinus adult and juvenile showing differences in the rostrum and fusion of skull elements in the adult.

A recent study on gill covers by Barske et al. 2020
“identify the first essential gene for gill cover formation in modern vertebrates, Pou3f3, and uncover the genomic element that brought Pou3f3 expression into the pharynx more than 430 Mya. Remarkably, small changes in this deeply conserved sequence account for the single large gill cover in living bony fish versus the five separate covers of sharks and their brethren.”

Figure 4. Skull of Polyodon from a diagram published in Gregory 1938, plus a dorsal view and lateral photo.
Figure 5. Skull of Polyodon from a diagram published in Gregory 1938, plus a dorsal view and lateral photo.

While comparisons to the feeding technique in paddlefish and basking sharks
appear in the literature (Matthews and Parker 1950, Haines and Sanderson 2017), these were presumed to be by convergence based on the single gill cover vs. multiple gill cover difference.

Figure 2. Skull of the dogfish shark, Squalus, superimposed on a graphic of the invivo shark. Yellow areas added to show the extent of the gelatinous material that fills the empty spaces above and below the cartilaginous rostrum (nasal homolog).
Figure 6. Skull of the dogfish shark, Squalus, superimposed on a graphic of the invivo shark. Yellow areas added to show the extent of the gelatinous material that fills the empty spaces above and below the cartilaginous rostrum (nasal homolog).

Relying on one, two or a dozen traits
to trump the other 234, 233 or 213 is called “Pulling a Larry Martin.” You don’t want to do that. Put aside your traditions, add taxa and let the unbiased software figure out where your taxon nests using the widely accepted hypothesis of maximum parsimony (= fewest changes) over a large set of character traits.

The present hypothesis of interrelationships
(Fig. 2) appears to be novel. If not, please advise so I can promote the earlier citation.


References
Barske L et al. (10 co-authors) 2020. Evolution of vertebrate gill covers via shifts in an ancient POU3f3 enhancer. PNAS 117(40):24876–24884.
Integration of swimming kinematics and ram suspension feeding in a model American paddlefish, Polyodon spatula. The Journal of Experimental Biology, 10.1242/jeb.166835, 220, 23, (4535-4547), (2017).
Matthews LH, Parker HW 1950. Notes on the anatomy and biology of the basking shark (Cetorhinus maximus (Gunner)). Proceedings of the Zoological Society of London 120(3):535–576.

Behind the scenes: that infamous ‘pterosaur precursor’ paper

Earlier we looked at
a pterosaur precursor paper that excluded all the pterosaur precursors documented 20 years ago (Peters 2000, 2007, 2009). Those four taxa were dismissed and omitted by Ezcurra et al. 2020, who cobbled together a chimaera of protorosaur and lagerpetid parts. Notably the lagerpetid foot showed it stood on only two toes. Pterosaur tracks and skeletons show pterosaurs stood on five toes. And that’s just the beginning of the sins committed by this 18 co-author venture into the imagination of confirmation bias.

From Eurekalert.org:
“Some questions still remain in this evolutionary mystery. Now that lagerpetids are the closest relatives of pterosaurs, why are they still lacking some of the key characteristics of pterosaurs, including the most outstanding of those – wings?

“We are still missing lots of information about the earliest pterosaurs, and we still don’t know how their skeletons transformed into an animal that was capable of flight,” said Nesbitt.”

pterosaur wings

Figure 1. Click to enlarge. The origin of the pterosaur wing and whatever became of manual digit 5?

Actually we already know how pterosaurs got their wings.
We’ve known for ten or twenty years (depends if your measure by data or taxa). The authors cited twenty-year-old Peters 2000. The authors provided no evidence that they actually looked inside that paper. Perhaps they believed the current propaganda and just dismissed the hypothesis. There was also a bit of wish fulfillment going on. Many workers have been hoping for decades to find a taxon to link dinos with pteros (see below).

Reporter George Dvorsky, confesses on Gizmodo.com
“These creatures [lagerpetids] seem an unlikely sister group from which pterosaurs emerged, which is probably why they’ve been ignored for so long.”

Lagerpetids seem unlikely because they have no traits shared exclusively with pterosaurs and several that dislodge them from consideration. By contrast, the omitted Cosesaurus clade has a long list of traits shared exclusively with pterosaurs.

Professor Kevin Padian
wrote a News & Views article to accompany the paper and put Ezcurra et al.  into historical perspective. Padian also omitted the Peters 2000 paper, which really should have been part of the history of pterosaur origins. Instead Padian concentrated on 18th and 19th century papers (why not just reference the Bible?), plus 4 of 10 citations were for Padian papers from the past, none on pterosaur origins. One citation was for young J. Gauthier’s PhD thesis at the genesis of software enabled phylogenetic analysis in which the clade Ornithodira (= pterosaurs + dinosaurs) was proposed and widely accepted without testing the Cosesaurus clade. To his credit, Padian 1983 reported that Dimorphodon (Fig. 2) was a biped, like birds and dinosaurs and he has ‘stuck to his guns’ ever since.

FIgure 8. Dimorphodon take off (with the new small tail).

Figure 2. Dimorphodon take off (with the new small tail).

I wrote to Dr. Padian:

Dear Kevin,

I’ll never forget the day when you and Chris Bennett gave me your sage words of wisdom: “Dave, you have to learn to perform a phylogenetic analysis.”

In 2000 when my Rivista paper came out on pterosaur origins, I added Langobardisaurus, Cosesaurus, Sharovipteryx and Longisquama to four previous published phylogenetic analyses. In each case those four nested closer to pterosaurs than all prior candidates… and for good reason. They shared more traits from snout to toes, including extradermal tissues.

Since then no one in the paleo community has let me know there are better candidates out there that I haven’t tested. On the other hand, no one has ever said, “Good job, you nailed it.”

Following your earlier advice I started adding taxa to a growing onliine cladogram at ReptileEvolution.com. Today there are 1770+ taxa on that one cladogram and the Cosesaurus clade still nests with pterosaurs, but they also nest within Lepidosauria in an overlooked third clade between sphenodonts and squamates.

It’s clear you have always preferred the ornithodire hypothesis, despite conflicting results when more taxa are added. Not sure why you stick to your guns when no evidence supports the hypothesis

Yesterday Ezcurra et al. came out with a chimaera they created out of a lagerpetid and a protorosaur that ran on two toes and called it a pterosaur precursor and you supported it with an enthusiastic news and views article, that, like Ezcurra et al. report, omitted the Cosesaurus clade.

You wrote, “Lagerpetids fit this profile, and, unlike other candidate relatives, they share some features with pterosaurs that other archosaurs do not.”

You also wrote,”Ezcurra et al. realized that, although lagerpetids didn’t fly, they share specific features with pterosaurs, such as … Their elongated hand (palm) bones (hyperelongated in pterosaurs, along with the fourth finger) suggest a good starting point for animals to evolve flight.”

By contrast, Ezcurra et al. wrote, ” …lagerpetids, as with other archosauromorphs, _lack_ the enlargement of both the deltopectoral crest of the humerus and the fourth manual digit that characterizes pterosaur wings.

We all see what we want to see. But my friends from Morristown NJ usually have a keener eye.

I was critical of Ezcurra et al. online here, with extensive evidence, if interested:

https://pterosaurheresies.wordpress.com/2020/12/10/new-pterosaur-precursor-study-excludes-all-pterosaur-precursors/

Best regards,

I have not heard back yet, and ironically, Dr. Padian is not famous for phylogenetic analysis.

Likewise I sent an email to co-author Max Langer:

Hi Max,

I was surprised, once again, to see Cosesaurus, Sharovipteryx and Longisquama omitted from a study on pterosaur origins. Very bizarre that taxa with prepubes, pterosaur-type pedes, extradermal membanes, antorbital fenestrae, four+ sacrals, elongate ilia, attenuated tails and a sternal complex were dismissed. 

Your new lagerpetid ran on two toes. That was the story, not any sort of relationship to pterosaurs.

Best regards,

I have not heard back yet.

Likewise I sent an email to lead author Martin Ezcurra
after he sent a PDF of the paper:

Thank you, Martin.

That is very kind of you to send the PDF. Fortunately someone else sent a copy in the meantime and I have been pouring over it.

I am going to be very critical of your paper. Here are the first two paragraphs.

It is good to see more material data appearing for lagerpetids, an enigmatic clade formerly known from pelvic and hind limb material and more recently from skull bits.

“Unfortunately Ezcurra et al. follow an established history of workers omitting competing taxa in pterosaur origin papers while cherry-picking comparative taxa and employing a chimaera of disassociated and unrelated bits and pieces from different genera. By contrast, the omitted taxa are complete, articulated, preserve soft tissue and nest closer to pterosaurs in several prior cladograms when added to them. Details follow.”

In addition, I think you missed some exciting details in the pes, overlooking fused bones. Your metatarsal 1 is actually metatarsal 2. Digit 1 is a vestige on this weird pes. Basal pterosaurs have five robust toes. Chanaresuchds lose pedal digit 5, so cannot be ancestral on that point alone. The taxa from Peters 2000 all have a robust pedal digit 5 on a short metatarsal, as in pterosaurs and as in Tanystropheus, which is why the first specimens of Tanystropheus were considered pterosaurian. Both are lepidosaurs, by the way.

Phylogenetically all the material continues to look chanaresuchid, not pterosaurian, as in prior lagerpetids.

Not sure who guided you not to include taxa from Peters 2000, 2007, 2009. Oh, well, it’s in print now. Most of the worst hypotheses on pterosaurs seem to come out of Southern England. Try to be more careful before accepting their suggestions.

This affair may remind you of the Oculudentavis scandal after a few days or weeks. Hopefully you’ll come out okay on the other end.

Best regards,

I have not heard back from Martin, either,

I only wish Ezcurra team and Padian
had been more critical of their own work (e.g. the two toes issue), had indicated they looked at the taxa in Peters 2000 and then rejected them and provided the reasons for that rejection, and contrary to that, simply shown their reconstruction of Cosesaurus, their reconstruction of Bergamodactylus and their reconstruction of their chimaera in one figure so readers could see their work for themselves with help from figure captions and call-outs. Figure 3 is from ReptileEvolution.com.

Figure 1. Bergamodactylus compared to Cosesaurus. Hypothetical hatchling also shown.

Figure 3. Bergamodactylus compared to Cosesaurus. Hypothetical hatchling also shown.

Please remember,
I was the second person to see pterosaur traits in Cosesaurus. Dr. P. Ellenberger was the first, but unfortunately, he thought Cosesaurus was a bird ancestor. He never considered pterosaurs. His views and tracings were chronicled here, here and here.

Together with the Oculudentavis scandal in March 2020,
this pterosaur precursor scandal and others, paleontology is going through a nadir right now. I hope things don’t get worse before they get better.


References
Ezcurra MD et al. (17 co-authors) 2020. Enigmatic dinosaur precursors bridge the gap to the origin of Pterosauria. Nature (2020). https://doi.org/10.1038/s41586-020-3011-4
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. 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

Cosesaurus paper on ResearchGate.net

https://gizmodo.com/scientists-uncover-the-mysterious-origin-of-pterosaurs-1845841696

https://pterosaurheresies.wordpress.com/2020/12/10/new-pterosaur-precursor-study-excludes-all-pterosaur-precursors/