A new, tiny choristodere, Mengshanosaurus, enters the LRT

It’s tiny and probably a hatchling because sister taxa are much larger.
Mengshanosaurus minimus (Yuan et al. 2021; Early Cretaceous, China; skull length 3.5cm) nests between Ikechosaurus and Champsosaurus in the LRT (subset Fig. 3). Note the indented remnants of the antorbital fenestra in the hatchling model (Fig. 1). Apparently the post-frontal fontanelle is not a pineal opening. Sister taxa do not have a pineal opening.

Figure 1. Full scale model of CT-scanned Mengshanosaurus skull.

Traditional skull misinterpretations continue in Yuan et al.
Yuan et al did not properly label several fused bones (corrected Fig. 2 right) because they don’t know which taxa are choristodere outgroups and last common ancestors. That remains a traditional academic enigma that no one else seems to want to resolve, confirm or refute (Fig. 3) by simply adding taxa to find out.

Figure 2. Holotype of Mengshanosaurus.

Similarly,
the authors had no idea where to nest choristoderes as reptiles. In the large reptile tree (LRT, 1879+ taxa; subset from 2013 in Fig. 3) choristoderes nest as derived proterosuchids. Tiny transitional taxa, like the BPI 2871 specimen, lose the antorbital fenestra. Sister clades within the Pararchosauriformes include the Parasuchia and Proterochampsia. Euarchosauriformes derived from Euparkeria evolve to Archosauria, Rauisuchia, Erythrosuchia, etc.

Figure 3. Subset of the large reptile tree focusing on the pararchosauriformes and the Choristodera.
Figure 3. Subset of the large reptile tree from 2013 focusing on the pararchosauriformes and the Choristodera. This has not changed much, but for the addition of taxa, like Mengshanosaurus between Ikechosaurus and Champsosaurus.

If you don’t know where your clade resides,
keep adding taxa until it becomes apparent and all candidate sister taxa are considered. Or just sneak a peek at the LRT. Don’t overlook tiny taxa. Often tiny taxa bridge gaps, forming transitions at the genesis of major clades in a process known as phylogenetic miniaturization. This time a tiny taxon just turned out to be a hatchling.

Figure 4. The choristodere, Champsosaurus laramiensis (USNM PL 544147) has a vestige antorbital fenestra in the usual place, anterior to the orbit. Here the frontal fontanelle is also present, as in Mengshanosaurus.

PS
Sometimes adult choristoderes also retain a vestige of the antorbital fenestra (Fig. 4).


References
Yuan M, Li D-Q, Ksepka DT and Yi H-Y 2021.
A juvenile skull of the longirostrine choristodere (Diapsida: Choristodera), Mengshanosaurus minimus gen. et sp. nov., with comments on neochoristodere ontogeny. Vertebrata PalAsiatic in press DOI: 10.19615/ j.cnki.2096-9899.210607

wiki/Mengshanosaurus – not posted yet

So, you want to be a paleontologist…

Summary for those in a hurry:
Becoming a paleontologist who can support a family is difficult and rare. Up-and-comers end up supporting powerful professors. Outsiders and insiders with new ideas are sometimes ridiculed and/or ignored to silence debate and prevent upsetting the status quo.

PS (added 24 hours later). If you’re serious about paleontology, see Dr. Chris Brochu’s well-considered and insightful comments (below). Dr. Brochu agrees, disagrees and adds more data to many of the points made here.

Once you get your PhD in paleontology…
sure it’s a happy day of celebration, a great achievement invested with time and treasure. But then reality sets in as you realize you are not automatically a ‘made man‘ as in the gangster movie, “Goodfellas.”

You still need to get that first good paying job in paleontology,
and those are hard to come by. Black 2010 reports, “it is extremely difficult for researchers to find jobs and secure funding for their research. Prior to the beginning of the 20th century most paleontologists were self-funded enthusiasts who either used their family fortunes (O.C. Marsh and E.D. Cope, for example) or sold fossils (the Sternberg family, for example) to underwrite their work. For most paleontologists most of the time, research funding comes in the form of grants.”

Through the grapevine
I hear that anywhere from 40 to 80% of grant money goes to the university or museum that provides office space for the paleontologist. (Is that correct?).

It comes as a disappointment to many PhDs
that they end up as preparators, docents, research assistants, artists and librarians, rather than highly-paid professors making decisions, doing field work in the summer and buzzing around the world doing book tours. That jarring dose of reality comes at a time when young, former students are starting from scratch, trying to buy a house, start a family, pay off loans and hoping to make a name for themselves by publishing discovery after discovery.

Evidently it is worse for female students and scientists…
Harassment and bullying were chronicled in a recent (April 14, 2021) PBS NOVA documentary you can access here.  Some notes follow:

PAULA JOHNSON, M.PH., M.D. (President, Wellesley College): “The best estimates are about 50 percent of women faculty and staff experience sexual harassment. And those numbers have not really shifted over time. If you think about science, right now, we have a system that is built on dependence, really, singular dependence of trainees—whether they are medical students, whether they are undergraduates, or if they’re graduate students—on faculty, for their funding, for their futures. And that really sets up a dynamic that is highly problematic. It really creates an environment in which harassment can occur.”

KATHRYN CLANCY, PH.D. (Biological Anthropologist): “Generally speaking, sexual forms of sexual harassment, like come-ons, unwanted sexual advances, those are actually the rarest forms of sexual harassment. They actually don’t happen very much; mostly you see putdowns.”

One woman noted, “an invitation to have a beer with someone important interested in your poster sometimes has little or nothing to do with your poster.” It is noteworthy that the dropout rate in STEM studies is higher in women, who suffer from unequal treatment according to this documentary.

Fossils are hard to come by.
If post-grads don’t find their own fossils in the field, the fossils that come in the door are going to be distributed by the professor as they please, like a mother bird feeding hungry nestlings. (BTW, I’m talking about paleontologists who like bones. Others in the petroleum industry with a Master’s Degree make better money than a PhD in dinosaur studies because they are in greater demand.)

In the typical bell-curve of success after a doctorate,
every year or so, some few do come to international attention for their discoveries and publications. Most do not. Many struggle just to keep up an association with a university, quite aware of the fact that year after year another clade of young, eager, intelligent, well-connected future paleontologists with scholarships are coming into the professors’ view with the exact same dream and goal.

When grad students and post-docs are trying to establish themselves,
they tend to maintain relationships with universities and ally themselves with groups that huddle around and support established professors. It’s the only game in town. These 20- and 30-somethings are known to professors as ‘cheap labor’ due to an over supply of young, eager and bright hopeful students.

Older, established professors decide
who of their underlings gets funding and who goes hungry. Well-known professors bring a lot of money into universities, so universities undervalue underlings based on this value system.

New hypotheses that upset those in textbooks are not welcome.
If those ideas come from outside the tribe, someone is sent out to dismiss and dismantle that radical. Discoveries and hypotheses are welcome only if the professor is made a co-author and it doesn’t depart from the paradigm (i.e.  supporting invalid clades like ‘Ornithodira‘, ‘Avemetatarsalia’, ‘Afrotheria‘, ‘Laurasiatheria’ and ‘Cetacea‘).

Peer review was not always part of the publication process,
but it is now. Dinerstein 2017 wrote, “The controversies that have plagued peer review from its earliest days, censorship, conflict of interest, the tension between early reporting and veracity, the need to fill space, the desire for prestige and income remain with us today. They may have assumed different forms, but at their core are flaws in a system designed by flawed humans. It may not be the best system, but it is the one we use.”

According to Kampourakis et al. 2015,
“The peer review process can be one of the most subjective endeavors in the scholarly world. It should not be, and it does not have to be subjective, but it can be. Each reviewer has his/her own conceptualizations, views, experiences, and biases, which can collectively impact the stance taken toward a manuscript.”

Established authors,
who are often established professors, who are well-known to established editors, have an advantage over independent researchers. Reviewers (= referees) are typically other professors hoping to get their work favorably reviewed when their time comes. If papers support the general narrative found in textbooks, they are more likely to be published. Departures that show textbooks are in error are at a disadvantage. No one wants to weaken the power of established professors, least of all other professors who understand how to play the game.

More on manuscripts from Kampourakis et al.
“Most manuscripts are not appropriate for publication when we initially receive them. They always have limitations, which authors themselves are unable to identify—we know this from our own publication experiences. Therefore, if the editors only relied on reviewers for a decision, this would most likely be a “reject” one in the first place. Reviewers are always experts in their domains, and when their review is constructive, it provides crucial feedback to authors.”

Actually reviewers/ professors are not experts in their domain if they are teaching untenable traditions as facts. You wouldn’t think that happens, but it does.

Actually reviewers/ professors can not be experts if the subject of the manuscript is a discovery, something new, something not seen or understood before by anyone.

The issue is: will reviewers and editors recognize ‘the new order’ or will they defend ‘the old order’, the one they teach, the one that creates their monthly paycheck coming from lectures and textbooks.

Discoveries should be a cause for celebration,
if followed by confirmation after testing using methods and materials.

Instead
discoveries by outsiders encourage young PhDs (e.g Naish, Cau, Witton) to start name-calling (e.g. ‘pseudoscientist‘, ‘crank)‘. Be aware that this sort of behavior has a long history in humankind, going back at least as far as the Romans, who called non-citizens ‘barbarians’. So, if you make a discovery don’t hold your breath waiting for accolades and citations (see John Ostrom link below).

Name-calling by teachers/ professors/ colleagues is inappropriate.
Better to help colleagues with suggestions or data if genuine errors are found.

Errors are everywhere.
I just spent the weekend correcting errors in the LRT. Finding new insightful data is its own reward.

The LRT is online day and night, world-wide,
available to anyone looking for taxon list suggestions and citations. In like manner, ReptileEvolution.com is a source for data. It would be great if someone else were to create a parallel study to confirm, refute and compare discoveries found here. In the last ten years, no one has yet ventured forth to do this, or threatened to do this. That may be because they are stuck in the present academic world and all of its restrictions.

You should do science
because you love science.

There are only so many discoveries to be made, and fewer every year.
No PhD wants to simply confirm what someone else has already discovered. That’s not why they spent their time and treasure getting their PhDs. They want their own discoveries. When someone else makes a discovery, that’s one less out there waiting to be discovered. That’s the sort of frustration that has led to name-calling when it should have led to unemotional scientific confirmation or refutation following scientific methods and materials.

And speaking of vague insults,
the latest I’ve heard is “Your methods are flawed.” Really? No more specific instruction? No actual testing of the methods? I keep hearing, “your character list needs to be expanded.” Daily testing shows this is a myth. Experts are not always correct, as you will sooner or later find out for yourself.

Once you’ve shown and labeled
all your taxonomic data, let the software recover a cladogram in which all sister taxa actually look alike. This simple method has led to several satisfying discoveries, like ancestors for pterosaurs, snakes, whales, and turtles back to Ediacaran worms.  Make all  your .nex files available to strangers. Have the balls to tell PhDs that genetic analyses deliver false positives in deep time studies, if that’s what your studies reveal.

IMHO
Your methods are flawed” comes off as a vague and baseless claim coming from an immature and insecure worker who has turned to projecting their own faults on others. Pressed for details, something real scientists are usually eager to fill an hour with, disgruntled post-grads usually retreat to social media. Funny that the ones who say, “your methods are flawed” do not repeat the same insult to their fellow PhDs when they make the same discoveries years later.

By design, the manuscript review process
usually takes months. It might take years. This is also a professional ‘brake’ on new ideas that keep the established professors behind their lecterns for as long as possible. Why would a professor return a favorable review on a paper that upsets his own hypotheses, lectures and textbooks? Professors rely on lectures and books for their salaries, royalties and status. Any manuscript that upsets the status quo is going to sit at the bottom of their growing IN pile for as long as possible, then begrudgingly returned with a ‘NO’. Cogent reasons are not required by editors.

In an ideal world
arguments should be published immediately, while the subject is still fresh in the public’s mind and before inaccurate myths get out there and spread into the world of general knowledge. Colleagues should treat each other more like co-pilots rather than saints vs. sinners.

Even if you become a tenured professor,
you are not always free to do what you want to do. “One way of getting rid of tenured professor, that’s known, is you ask the person to report on their research and you load them up with teaching and you give them a lousy office. And then eventually they’ll just quit.” Eric Weinstein on Joe Rogan #1626 3:15 https://www.youtube.com/watch?v=l1jTUhwWJYA
Even tenured professors are steered.

The red pill and blue pill.
This is a common meme from a scene in the 1999 film The Matrix. It refers to a choice between the willingness to learn a potentially unsettling or life-changing truth, by taking the red pill, or remaining in contented ignorance with the blue pill. Over the last ten years of building the LRT I’ve come to realize when a PhD has taken the blue pill. Keep working and soon you will, too.

That’s why this blogpost exists.
Blogposts sponsored by major publications like Scientific American, are less about science and more about journalism, reporting the untested results of published papers.

Textbooks are too often used as unchangeable bibles,
instead of jumping off points for the next set of discoveries.

American physicist, Richard Feynman once said,
“As a matter of fact, I can also define science another way: Science is the belief in the ignorance of experts.”

Historically
it has taken an outsider, someone not beholding to one professor or to the rest of the professors, to clean house. Yale paleontologist John Ostrom was an insider with an outsider idea and even he had a frustrating story to tell about how long his ideas took to come to consensus.

The video above
at 33:40 discusses the tiny (5%) number of those who train for jobs in academia actually get jobs in academia. It also discusses the large percentage (50%) of grant money that goes directly to the university. Under this system the university hires students, often foreign students, to do the teaching for low wages leaving the successful grant writers to keep writing expensive grant applications.

ResearchGate.net
reports readership for my papers and manuscripts on their site has surpassed 5000 with some papers exceeding 600 reads. That’s good to hear. Just getting the information out is why anyone writes a manuscript. Nowadays everything is downloaded. If you’re not a card-carrying student or faculty member at many universities, you’re not going to be allowed in their libraries to browse the increasingly old-fashioned book shelves.

Finally, it’s up to others to approve or dismiss,
and that’s out of our control no matter if we publish fact or fancy, online or in the literature. Good luck in your career. Don’t let anything restrict your studies.


References
Black R 2010. https://www.smithsonianmag.com/science-nature/who-pays-for-dino-research-66263095/
Dinerstein C 2017. The surprising history of peer review. American Council of Science and Health. online here.
Kampourakis K et al. (3 co-authors) 2015. Peer review and Darwinian selection. Science & Education 24:1055–1057.

collegescholarships.org/scholarships/science/paleontology.htm
palass.org/awards-grants/grants/list-external-grants
usnews.com/education/best-graduate-schools/articles/what-paleontology-is-and-how-to-become-a-paleontologist

john-ostrom-the-man-who-saved-dinosaurs/
indeed.com/how-much-does-a-paleontologist-make
work.chron.com/salary-palaeontologist

For more PhD shenanigans, click on these links:
Padian 1 –  Padian 2 
Naish
Witton
Hone and Benton  –
Benton 1
Ezcurra 1
Cau 1

“The amazing diversity of fishes” YouTube video

Dr. Phil Hastings,
Scripps professor and curator of the SIO Marine Vertebrate Collection delivers an online lecture and slide show sponsored by the University of California Television (UCTV). It runs for about an hour.

This is a traditional view of fishes
lacking any mention of fossil taxa.

Unfortunately
Hastings follows molecular data. Hastings mentions that we humans are indeed members of the Osteichthys. Ichthyologist Neil Shubin and artist Ray Troll are also mentioned.

By contrast,
the large reptile tree (LRT, 1836+ taxa) presents a distinctly different view of fish systematics because it includes fossils and minimizes taxon exclusion.

The razorfish, Aeoliscus, enters the LRT as an upside-down sea horse

Figure 1. Aeoliscus in vivo at full scale on a 72 dpi monitor.

Aeoliscus strigatus (Günther 1861, aka Centriscus strigatus, Amphisle strigata; 15cm) is the extant razorfish or shrimpfish. In the large reptile tree (LRT, 1834+ taxa) the shrimpfish nests with the sea horse, Hippocampus (Fig. 2). Thus Aeoliscus can be thought of as an upside-down sea horse despite many morphological difference (= no other tested vertebrate is closer). The dorsal fins have migrated to the caudal area. The caudal fin migrates to the anal area, bending the vertebral column to do so (Fig. 2). The tiny mouth, perhaps the smallest among vertebrates, is used like an eye-dropper to suck up minute brine shrimp. The preoperculum and operculum are large to produce suction for the tube mouth.

The preoperculum extends anteriorly beyond the orbit, merging with the quadrate (Fig. 2, at least in Gregory’s 1933 drawing). The lacrimal is absent (at least in Gregory’s 1933 drawing). As in the sea horse the naris is close to the orbit. The orbit is confluent with the antorbital fenestra. The supratemporal is absent or fused.

The shape of Aeoliscus was for hiding among sea grasses and other vertical sea floor environmental elements. The counter-shading of the body increases the illusion of slender background elements.

Figure 2. Aeoliscus anatomy from Gregory 1933 compared to related taxa in the sea horse / pipefish clade. Tetrapod analog colors applied here.

Aeoliscus lives in shallow sunlit waters
protected from predators by the poisonous spines of nearby brainless sea urchins. Fertilized eggs and hatchlings drift without parental care. Males and females are nearly identical.

References
Gregory WK 1933. Fish skulls. A study of the evolution of natural mechanisms. American Philosophical Society 23(2) 1–481.
Günther A 1861
. Catalog of Fishes in the British Museum 3: 586pp. British Museum, London.

wiki/Hippocampus
wiki/Aeoliscus

Bears, bears and more bears

This post had its genesis
in a recent YouTube video all about bears by Moth Light Media. After phylogenetic analysis in the large reptile tree (LRT, 1834+ taxa, subset Fig. 1) ‘bears’ are no longer monophyletic. Instead the various extant ‘bears’ are better considered giant kinkajous, weasels, wolverines and bush dogs, all converging on similar ‘bear’-like morphologies.

Figure 1. Subset of the LRT focused on Carnivora, a placental mammal clade. Note the polyphyletic nesting of various 'bears' indicating that they are all just large kinkajous, weasels, wolverines and bush dogs converging on similar bear-like morphologies.

Figure 1. Subset of the LRT focused on Carnivora, a placental mammal clade. Note the polyphyletic nesting of various ‘bears’ indicating that they are all just large kinkajous, weasels, wolverines and bush dogs converging on similar bear-like morphologies. Note the separation of seals (dark yellow) from sea lions (peach).

Jiangzuo and Flynn 2020
discussed the earliest ursine bear and the origin of plant-dominated omnivory in Carnivora. Unfortunately they worked within an invalid phylogenetic context brought about by taxon exclusion. The wolf, Canis lupus, was their outgroup taxon. So their cladogram was upside-down compared to the LRT (Fig. 1). Basalmost members of Carnivora and their outgroups among basalmost Placentalia were all agile arboreal omnivores, not digitigrade cursors (runners), like Canis.

Jiangzuo and Flynn consider the spectacled bear,
Tremarctos, a member of the ursine bears. In the LRT Tremarctos arises from the bush dog, Speothos, far apart from ursines.

Jiangzuo and Flynn consider the wolverine,
Gulo, a member of the mustelids. In the LRT the short face bear, Arctodus, arises from the wolverine, Gulo, apart from ursines. 

Jiangzuo and Flynn consider the giant panda,
Airluropoda, a type of bear. In the LRT it arises from the herbivorous kinkajou (genus: Potos) before the appearance of the ancestor of the rest of the ‘bears’, Mustela, the weasel.

Jiangzuo and Flynn do not include
Speothos or Potos in their text. The authors separate Gulo in the clade Mustelida, apart from bears in their study. So taxon exclusion mars this otherwise detailed study of bear dentition and diet.

In like fashion,
McLellan and Reiner 1994 also excluded a long list of pertinent taxa in their review of bear evolution.

Sharp-eyed readers will note the addition of two taxa
to the Carnivora, the sea otter (Enhydra) and the basal walrus (Protodobenus).


References
Jiangzuo Q and Flynn JJ 2020. The earliest ursine bear and the origin of plant-dominated omnivory in Carnivora. iScience 23, 101235, June 26, 2020.
McLellan B and Reiner DC 1994. A review of bear evolution. Int. Conf. Bear Res. and Manage. 9(1):85-96

 

Fossiomanus and Jueconodon enter the LRT as pre-mammal diggers

As the headlines reported,
(see below) these two late-surviving pre-mammals lived under the feet of Early Cretaceous dinosaurs and probably only came out after dark.

From the Mao et al. 2021 abstract:
“Mammaliamorpha comprises the last common ancestor of Tritylodontidae and Mammalia plus all its descendants. Tritylodontids are nonmammaliaform herbivorous cynodonts that originated in the Late Triassic epoch, diversified in the Jurassic period and survived into the Early Cretaceous epoch. Eutriconodontans have generally been considered to be an extinct mammalian group, although different views exist.”

“Here we report a newly discovered tritylodontid and eutriconodontan from the Early Cretaceous Jehol Biota of China. Eutriconodontans are common in this biota, but it was not previously known to contain tritylodontids.”

Confirmation on those points!
In the large reptile tree (LRT, 1825+ taxa; subset Fig. 4) Fossiomanus nests with Oligokyphus and the tritylodonts. The other new burrowing pre-mammal, Jueconodon nests with Liaocondon, and other eutriconodonts close to Gobiconodon and Repenomamus.

Figure 1. Fossiomanus in situ in two ventral views, plus manus, pes and pelvis reconstructed. Teeth colored. Taphonomically shifted pectoral girdle repaired on right. The current view of the skull material prevents a reconstruction at this time.
Figure 2. Skull of Jueconodon based on data from Mao et al. 2021.

Mao et al. continue:
“These fossils shed light on the evolutionary development of the axial skeleton in mammaliamorphs, which has been the focus of numerous studies in vertebrate evolution and developmental biology. The phenotypes recorded by these fossils indicate that developmental plasticity in somitogenesis and HOX gene expression in the axial skeleton—similar to that observed in extant mammals—was already in place in stem mammaliamorphs. The interaction of these developmental mechanisms with natural selection may have underpinned the diverse phenotypes of body plan that evolved independently in various clades of mammaliamorph.”

Figure 3. Cladogram from Mao et al. 2021, color overlays added here to show how LRT divides these clades. Compare to figure 4.

Usually, No hypotheses like this can proceed without first establishing a valid phylogeny.’ Parts of Mao et al. match the LRT. Unfortunately, Mao et al. follow invalid academic tradtion as they also include and therefore nest multituberculates with pre-mammals, rather than with rodents and plesiadapiformes in the gnawing clade, Glires. Just add pertinent taxa to resolve this problem. So far PhDs have been reluctant to do this and so the myth continues untested except here.

Mao et al. nest Jueconodon between Liaoconodon and Chaoyangodens (Fig. 3). In the LRT (Fig. 4) Jueconodon also nests with Liaoconodon, but Chaoyangodens nests as a monotreme mammal, basal to the echidna and platypus (Tachyglossus and Ornithorhynchus).

Mao et al. nest Fossiomanus with Kayentatherium, basal to four other tritylodontids including Tritylodon and Oligokyphus among mutually tested taxa. In the LRT (Fig. 4) Fossiomanus nests similarly.

Figure 4. Subset of the LRT focusing on pre-mammals with the addition of Fossiomanus and Jueconodon. Compare to original cladogram in figure 3 and to the LRT for a look at related taxa.

Mao et al. mention Liaoconodon often:

  1. The triangular shape of the skull may have been exaggerated by the crush of
    the specimen, but compared to those that have the similar preservation, such as Jeholodens, Liaoconodon, and Chaoyangodens, the triangular shape of Jueconodon is distinctive.
  2. The morphology of the mandible is similar to those of other eutriconodontans, such as Liaoconodon (Meng et al., 2011). Given that Liaoconodon was interpreted as a semiaquatic animal (Chen and Wilson, 2015), the similar mandible in both species indicate that the lower jaw and teeth of Jueconodon were not specialized for digging.
  3. The ossified Meckel’s cartilage on each side is preserved but displaced from its anatomical position. This suggests that the transitional mammalian middle ear, as best shown in Liaoconodon (Meng et al., 2011), was present in the fossorial eutriconodontans.
Figure 5. Skull of Liaoconodon.
Figure 6. Liaoconodon in situ.

Mao et al. report, “the Manda cynodont and mammaliaforms that are considered terrestrial.
Compared to extant mammals, Fossiomanus sinesis is superficially similar in body size and shape to the Cape dune mole-rat Bathyergus suillus, the largest subterranean scratch-digger species of the African mole-rats (Montoya-Sanhueza et al., 2019). However, they differ fundamentally in the axial skeleton in that mole-rat has the rodent body plan with the ancestral PV count of mammals.”

References
Mao F-Y, Zhang C, Liu C-Y and Meng J 2021.
Fossoriality and evolutionary development in two Cretaceous mammaliamorphs. Nature (advance online publication)
doi: https://doi.org/10.1038/s41586-021-03433-2
https://www.nature.com/articles/s41586-021-03433-2

wiki/Fossiomanus
wiki/Cape_dune_mole-rat

http://www.sci-news.com/paleontology/fossiomanus-sinensis-jueconodon-cheni-09534.html

https://www.amnh.org/explore/news-blogs/research-posts/burrowing-mammal-ancestors-discovered

Palaeocene Massamorichthys enters the LRT close to zebra fish

Revised April 28, 2021
with a slight shift of Massamorichthys closer to Danio, the tiny zebra fish, derived from mackerels.

Massamorichthys wilsoni (Murray 1996; up to 20cm; Paleocene) is a small extinct transitional taxa linking Scomberoides to more derived taxa, including Danio. It does not appear to be related to Percopsis Massamorichthys lacks a crest, a trait present in basal taxa. This fish is related to tuna (Thunnus) and mackerel (Scomber).

Does this mean
Massarmorichthys is chronologically correctly nested? In other words, are all the phylogenetic descendents younger than Massamorichthys? The answer is….No. Sphenocelphalus is a Late Cretaceous perch. Plectocretacicus is an early Late Cretaceous oarfish ancestor.

PS
Massarmorichthys looks like your standard, plesiomorphic fish. It is. Don’t omit such taxa from your cladograms just because they are not weird, scary or gigantic. Here and elsewhere the plain and small taxa are important, too.

References
Murray AM 1996. A new Paleocene genus and species of percopsid, †Massamorichthys wilsoni (Paracanthopterygii) from Joffre Bridge, Alberta, Canada. Journal of Vertebrate Paleontology 16(4):642–652.

Proteus, the blind cave salamander, enters the LRT

Losing its maxilla
(Fig. 1) did not stop this taxon from sporting a lot of other teeth in the palatine, ectopterygoid and maybe the vomer, even though only the premaxillary teeth line up with dentary teeth.

Figure 1. Skull of Proteus the white olm. Colors added. Note the lack of a lacrimal and maxilla.

Figure 1. Skull of Proteus the white olm. Colors added. Note the lack of a lacrimal and maxilla.

 Proteus the white olm
(Figs. 1, 2), is a blind cave salamander with a long torso, tiny limbs and external gills (Fig. 2).

Figure 2. Skeleton of Proteus, the white olm.

Figure 2. Skeleton of Proteus, the white olm.

Proteus anguinus
(Laurenti 1768) nests with Necturus, the mudpuppy. The lacrimal and maxilla are absent. The postorbital and postfrontal are stretched out. External gills enable Proteus to remain underwater. Apparently the dorsal portion of the vertebral column is very short (about 5 vertebrae), with the majority comprised of lumbar vertebrae (without dorsal ribs).


References
Laurenti JN 1768. Synopsin Reptilium. J.T. de Trattnern, Viennae, pp. 35–36.

wiki/Olm

Fruitafossor: now a Late Jurassic echidna from Colorado

While reviewing the terrestrial descendants of tree shrews
yesterday, the Late Jurassic Fruitafossor (Figs. 1, 2) stuck out as a chronological misfit as it nested in the otherwise Tertiary edentates (= Xenarthrans).

Here is the problem,
and the solution.

A Jurassic edentate? No.
Fruitafossor windscheffeli (Luo and Wible 2005) used to nest in the LRT with digging edentates, like the armadillo-mimic, Peltephilus (Miocene), and for good reason…

Wikipedia reports,
“The teeth of Fruitafossor bear a striking resemblance to modern armadillos and aardvarks. Its vertebral column is also very similar to armadillos, sloths, and anteaters (order Xenarthra). It had extra points of contact among similar to the xenarthrous process that are only known in these modern forms.”

By contrast, Wikipedia concludes,
“Its shoulder-girdle is similar to a platypus or reptile, but many other features are more similar to most other modern mammals.”

What would Larry Martin say?
Run a complete analysis. Don’t rely on one, two or a dozen traits. And the Late Jurassic is so early in mammal evolution that it becomes important, too. There were fewer mammal clades back then. Edentates had not yet arrived.

Figure 5. Several drawings from Zhou and Wible that one must trust for accuracy. The verification data is too fuzzy to validate.

Figure 1. Several drawings from Zhou and Wible that one must trust for accuracy. The verification data is too fuzzy to validate.

So is Fruitafossor a Late Jurassic edentate?
Or an edentate-mimic in the Late Jurassic?
With current scoring in the LRT, shifting Fruitafossor from the edentates to the base of the Monotremata adds 23 steps. Shifting to Early Cretaceous Lactodens within the Monotremata adds just 17 steps, the lowest number I could find. Lactodens has typical differentiated teeth and five fingers with small, sharp claws, traits not shared with Fruitafossor + edentates. Lactodens nests with the echidnas, Tachyglossus (extant, Figs. 3–5) and Cifelliodon (Early Cretaceous; Fig. 3). The latter has simple blunt teeth and the former is a known digger.

Figure 2. Fruitafossor in situ from Digimorph.org and used with permission and here colorized to an uncertain extent.

Figure 2. Fruitafossor in situ from Digimorph.org and used with permission and here colorized to an uncertain extent.

So let’s reexamine scored traits… and solve this conundrum.
Has the LRT met its match? Very few skull traits are known from Fruitafossor. Even so, earlier I overlooked or mis-scored the following that gain importance in hindsight:

Fruitafossor:

  1. orbit contacts the maxilla
  2. 4 rather than 5 sacrals,
  3. coracoid present
  4. I could not score hind limb length without a pes and estimates won’t do
  5. proximal sesamoid of fibula present
  6. fibula diameter greater than half of tibia
  7. dorsal osteoderms absent (I misinterpreted scattered elements at Digimorph.org)

Tachyglossus:

  1. retroarticular process present as in Fruitafossor
  2. metacarpal 1 and 2 are the longest as in Fruitafossor
  3. longest manual digit 3 as in Fruitafossor
  4. manual digit 4 narrower than 3 as in Fruitafossor

Cifelliodon:

  1. three molars, as in Fruitafossor

Figure 1. Early Cretaceous Cifelliodon is ancestral to the living echidna, Tachyglossus according to the LRT. The lack of teeth here led to toothlessness in living echidnas. The skull of Tachyglossus is largely fused together, lacks teeth and retains only a tiny lateral temporal fenestra (because the jaws don't move much in this anteater. Compared to Cifelliodon the braincase is greatly expanded, the lateral arches are expanded and the two elements fuse, unlike most mammals.

Figure 3. Early Cretaceous Cifelliodon is ancestral to the living echidna, Tachyglossus according to the LRT. The lack of teeth here led to toothlessness in living echidnas. The skull of Tachyglossus is largely fused together, lacks teeth and retains only a tiny lateral temporal fenestra (because the jaws don’t move much in this anteater. Compared to Cifelliodon the braincase is greatly expanded, the lateral arches are expanded and the two elements fuse, unlike most mammals.

Figure 3. Tachyglossus skeleton, manus and x-rays. Note the perforated pelvis.

Figure 4. Tachyglossus skeleton, manus and x-rays. Note the perforated pelvis.

Figure 1. The echidna (genus: Tachyglossus) in life. This slow-moving spine-covered anteater has digging claws.

Figure 5. The echidna (genus: Tachyglossus) in life. This slow-moving spine-covered anteater has digging claws.

Results (as you might imagine, given these changes):
Fruitafossor is an edentate-mimic nesting basal to Cifellidon and Tachyglossus as a Late Jurassic echidna and monotreme in the LRT. Glad to get rid of that problem!

In their original description of Fruitafossor,
Luo and Wible 2005 nested their discovery between a monotreme clade and a clade with the mammal-mimic, Gobiconodon at its base, then a clade with another egg-laying mammal, Tinodon at its base, then a pangolin ancestor, Zhangheotherium, then a rabbit ancestor Henkelotherium, then two other monotremes, Dryolestes, Amphitherium and the carnivorous marsupial, Vincelestes.  Luo and Wible tested Tachyglossus, but not Cifelliodon, which was published in 2018. Note the simple, blunt teeth in Cifelliodon, nearly matching those in Fruitafossor. Given that the only fossil of Fruitafossor is a bit jumbled, it is possible that it, too, had five fingers in vivo, like other monotremes. With only four fingers (Fig. 1) Fruitafossor had a good excuse for pretending to be an edentate.

So, yes, the LRT was up to the challenge.
But it took insight, lacking until now, to provide the correct matrix scoring. I’m happy to announce that the twenty or so corrections made yesterday were added to the 120,000 or so corrections made over the past ten years. With these corrections the LRT gets better and stronger every week. Minimizing taxon exclusion maximizes the opportunity to correctly nest new and enigma taxa with old and established taxa, even if the new and old specimens are incomplete or scattered about.

The earlier August 2017 blogpost for Fruitafossor
was updated yesterday to erase old errors and enter the corrections.


References
Huttenlocker AD, Grossnickle DM, Kirkland JI, Schultz JA and Luo Z-X 2018. Late-surviving stem mammal links the lowermost Cretaceous of North America and Gondwana. Nature Letters  Link to Nature
Luo Z-X and Wible JR 2005. A late Jurassic digging mammal and early mammal diversification. Science 308:103–107.
Shaw G 1792. Musei Leveriani explicatio, anglica et latina.

wiki/Fruitafossor
digimorph.org/specimens/Fruitafossor_windscheffeli/

 

Misinformation from whale expert JGM ‘Hans’ Thewissen

Figure 1. Book cover for 'The walking whales" by JGM Hans Thewissen author. April 2019 pub date.

Figure 1. Book cover for ‘The walking whales” by JGM Hans Thewissen author. April 2019 pub date.

A 2014 book
on the origin of whales (Fig. 1) by Dr. JGM ‘Hans’ Thewissen just had another burst of publicity from Discover Magazine online (see link below). Article headline: How ancient deer lost their legs and became whales”

Ancient deer???

Dr. Thewissen is a professor
at Northeast Ohio Medical University.

According to the Discover article by Joshua Rapp Learn:
“Cetaceans include everything from dolphins to whales.”

By contrast,
in the large reptile tree (LRT, 1818+ taxa; subsets Figs. 5, 6) Cetacea is no longer a clade. That’s because traditional ‘whales’ are diphyletic with separate ancestries still not recognized by whale experts like Dr. Thewissen. Odontocetes (toothed whales, Figs. 2, 6) arise from tenrecs (which also echolocate). Mysticetes (baleen whales, Figs. 3–5) arise from mesonychids, hippos, anthracobunids and desmostylians.

Figure 8. Odontoceti (toothed whale) origin and evolution. Here Anagale, Andrewsarchus, Sinonyx, Hemicentetes, Tenrec Indohyus and Leptictidium precede Pakicetus. Maiacetus and Orcinus are aquatic odontocetes.

Figure 2. Odontoceti (toothed whale) origin and evolution. Here Anagale, Andrewsarchus, Sinonyx, Hemicentetes, Tenrec Indohyus and Leptictidium precede Pakicetus. Maiacetus and Orcinus are aquatic odontocetes.

According to the Discover article:
“Indohyus belonged to the even-toed group of ungulates, which today includes giraffes, horses, pigs and cetaceans. Indohyus basically looked like a tiny little deer, a deer the size of a cat,” says Hans Thewissen, a professor at Northeast Ohio Medical University who has studied whale evolution for years and wrote the book The Walking Whales: From Land to Water in Eight Million Years. Today, a distant deer-like relative called the water chevrotain (or African mouse-deer) can be found from central to southern Africa. These deer eat flowers and fruits and live near rivers, which they use as escape routes to flee land-based predators or even eagles.

Ungulates have no relationship to whales in the LRT.
Think of it. Four, two or one-toed hooves to flippers? That’s untenable, but evidently that’s what taxon exclusion gives you. Simply adding taxa in the LRT (Figs. 2–4) shows that Thewissen’s study suffered from taxon exclusion prior to Pakicetus (Fig. 2), the most basal taxon common to both studies.

Figure 1. Rorqual evolution from desmostylians, Neoparadoxia, the RBCM specimen of Behemotops, Miocaperea, Eschrichtius and Cetotherium, not to scale.

Figure 3 Rorqual evolution from desmostylians, Neoparadoxia, the RBCM specimen of Behemotops, Miocaperea, Eschrichtius and Cetotherium, not to scale.

Figure 1. Taxa in the lineage of right whales include Desmostylus, Caperea and Eubalaena. The tiny bit of jugal posterior to the orbit (in cyan) is found in all baleen whales tested so far. The frontals over the eyes are just roofing the eyeballs in Desmostylus, much wider in Caperea and much, much longer in Eubalaena.

Figure 4. Taxa in the lineage of right whales include Desmostylus, Caperea and Eubalaena. The tiny bit of jugal posterior to the orbit (in cyan) is found in all baleen whales tested so far. The frontals over the eyes are just roofing the eyeballs in Desmostylus, much wider in Caperea and much, much longer in Eubalaena.

According to the Discover article:
“Thewissen’s research examining stable isotopes in Indohyus fossils shows they ate land plants, but their dense bones suggest they spent a lot of time in the water. The hippopotamus — the closest living relative of whales that live outside the ocean — also has dense bones, which help weigh it down while walking along the bottom of lakes or rivers. The evolutionary descendant of Indohyus, called Pakicetus, began to adopt a more aquatic lifestyle as they abandoned a vegetarian diet, based on the way their teeth look, Thewissen says.”

So this explains why Thewissen did not answer my emails.
Two years earlier he had authored a book (Fig. 1) that promoted the myth of a single origin of all whales originating from hoofed ungulates. The news I sent him, that whales were not a single clade, was probably upsetting, considering the time, treasure and reputation Thewissen put into his career and his publications. You can’t fix print once it is printed.

Figure 3. The oreodont-mesonychid-hippo-desmoystlian-mysticete clade subset of the LRT

Figure 5. The oreodont-mesonychid-hippo-desmoystlian-mysticete clade subset of the LRT

It should be up to professionals and PhDs
to build matrices and run analyses of fossil taxa. That’s what they are getting paid to do. They are the ones who know how to run the analyses. They are the ones who have access to fossils. They have professional colleagues, post-docs, PhD candidates, undergrads, volunteers and grants. Since the pros and PhDs have chosen to exclude so many pertinent taxa, amateurs are taking up the slack, hoping to contribute to this ancient science we call paleontology.

Figure 4. Subset of the LRT focusing on the odontocetes and their ancestors.

Figure 6. Subset of the LRT focusing on the odontocetes and their ancestors.

Taxon exclusion remains the number one problem
vexing paleontology and paleontologists. Adding taxa to minimize taxon exclusion is what the LRT is all about. It resolves problems like the origin of whales with taxa that document in detail the gradual accumulation of traits (Figs. 3, 4) we expect from microevolution over deep time, now back to Ediacaran nematodes.

Since this is science,
anyone can repeat this experiment simply by following the materials and methods. You don’t have to be a scientist. You don’t have to be an expert. That will come with time and study, the same way it comes with time and study for those who pay dearly for their education. Don’t trust me. Don’t trust others, even paid professionals with PhDs. Build your own matrix and run the analyses yourself to find out for yourself that deer, or any other ungulate, did not give rise to whales.


References
Thewissen JGM et al. (4 co-authors) 2007. Whales originated from aquatic artiodactyls in the Eocene epoch of India. Nature 450:1190–1194.

Nature Comment:Adding taxa documents the origin of odontocetes from anagalids, leptictids and tenrecs (which echolocate) leading to Indohyus and Pakicetus apart from the origin of mysticetes from mesonychids, hippos, anthracobunids and desmostylians with Desmostylus closer to right whales and Behemotops closer to rorquals. Cladogram here: http://reptileevolution.com/reptile-tree.htm and manuscript here: https://www.researchgate.net/publication/328388746_The_triple_origin_of_whales”

Thewissen JGM 2019, 2014. The walking whales. From land to water in eight million years. University of California Press. 256pp.

ResearchGate.net manuscript on the triple origin of whales

Publicity:
article by Joshua Rapp Learn in Discover Magazine online: how-ancient-deer-lost-their-legs-and-became-whales