Dinosaur books

At one time
I wanted to write and illustrate a dinosaur book. I had an idea for one (Fig. 1) and was inspired by the writers and artists of the Dinosaur Renaissance. It took several years…

Figure 1. The cover of Giants, the book that launched my adult interest in dinosaurs, pterosaurs and everything inbetween.

Figure 1. The cover of Giants, the book that launched my adult interest in dinosaurs, pterosaurs and everything inbetween.

Then
I got a contract to do my first book. That begat another and another. The shelf life was no more than one year for any of them. None went to second editions, though several had foreign versions. Reviews were good. Libraries stocked them. Book signings were fun, when there was advanced publicity. Every so often there was a big or small check in the mail. Now Amazon keeps them alive, if just barely. Reviews are still good…

Nowadays
I would not want to write and illustrate another dinosaur book. New discoveries make at least part of the text and part of the depiction of its subjects obsolete, sometimes before shelf life is over. The amount of data needed to be covered is staggering. More pages mean the price the book rises out of the ability to pay for many potential readers. With book publication, there are no ‘do-overs’ or ‘updates.’ What’s done is done. And then there are always the nagging typos. There’s a lot of work involved. And it has to be polished perfect. Editors, working for publishers, have their say. So do collaborators, if any. You have to put your life on hold to get the thing done by deadline. And when it’s done, it sits on a bookstore shelf, just one more Christmas or birthday present vying for the consumer’s eye.

It’s much better to post blogs
and nurture growing websites, like ReptileEvolution.com. These can be updated at will in one’s spare time. There are no paper or printing costs. No ships and trucks to distribute them. No bookstores to deal with. No deadlines. News can be reviewed within a day, while it’s still fresh. Everyone in the world has free access to your work. They can focus in on what they really like and ignore the rest at no cost. And one more thing (quoting Steve Jobs) that books can’t provide: animation. There’s no profit in web publishing, but money was never the front and center issue.

Figure 2. Sample animation you’ll never see in a book. The Vienna specimen of Pterodactylus (wings folded). Animation opens the wings and legs to reveal the true shape of pterosaur wings, stretched between the elbow and wingtip with a short fuselage fillet extending from elbow to mid femur.

Even so
I’m glad I went through that book phase. It had its time and place. The process led me to interact with others of like interest. Some of them are PhDs. Others are fellow artists and writers. Everyone should have a hobby to keep in touch with the world and vice versa.

I was inspired to write this blog post
after seeing parts of Walking with Dinosaurs 3D on YouTube. Click here to see it. So much talent and effort went into this— truly outstanding visuals …but the dialog was horrible, as most others agree. And there are a few new dinosaur books out now, updating older dino books. I wish them all well. Someday, perhaps decades from now, those books will either be considered cherished classics or outdated, ready to be updated. It’s all good.

References
www.DavidPetersStudio.com/books
www.ReptileEvolution.com

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Coincidence? Or Discovery?

A recent reply (see below) to an earlier post bears noting:

Diandongosuchus nests as a basal phytosaur when choristoderes and basal younginoids are included, far from Qianosuchus, which also does not nest with poposaurs, which are all bipedal (or formerly bipedal) herbivores, a far cry from Diandongosuchus.

Figure 1. Diandongosuchus nests as a basal phytosaur when choristoderes and basal younginoids are included, far from Qianosuchus, which also does not nest with poposaurs, which are all bipedal (or formerly bipedal) herbivores, a far cry from Diandongosuchus.

David Marjanović on April 12, 2017 at 3:16 am said: 
“The redescription of Diandongosuchus (Fig. 1) has now been published in open access. I’m afraid I can’t congratulate you. The new paper, and the SVP abstract before it, uses data you didn’t (and couldn’t) use – you were right for the wrong reasons. No congratulations for coincidences. :-|  “

Reply ↓
davidpeters1954 on May 22, 2017 at 8:31 pm said:
“So, phylogenetic analysis and expanding the inclusion set are the wrong reasons? Tsk, tsk, David. Your bias is showing.”

Back story:
Diandongosuchus (Li et al. 2012) was originally nested with poposaurs. Within a few days of its publication, Diandongosuchus was added as a taxon to the large reptile tree (LRT) and it nested not with poposaurs, but at the base of the phytosaurs. Several other blog posts here, here and here further illustrated the link.

Recently 
Stocker et al. 2016 also nested Diandongosuchus with phytosaurs and shortly thereafter news of that publication was posted here,

Botton line:
Stocker et al. did not recognize the earlier discovery. It was easy to Google. It would have been appropriate to add the original discoverer to the list of authors. This is common practice, even when that person is deceased. More recently Dr. Marjanović withheld congratulations and demeaned the scientific method by which the discovery was attained (an expanded taxon list employed in phylogenetic analysis) as “the wrong reasons.”

 

Carl Sagan once wrote:
“In a lot of scientists, the ratio of wonder to skepticism declines in time. That may be connected with the fact that in some fields—mathematics, physics, some others—the great discoveries are almost entirely made by youngsters.”

“The suppression of uncomfortable ideas may be common in religion or in politics, but it is not the path to knowledge; it has no in the endeavor of science. We do not know in advance who will discover fundamental insights.”

“There are many hypotheses in science which are wrong. That’s perfectly all right; they’re the aperture to finding out what’s right. Science is a self-correcting process. To be accepted, new ideas must survive the most rigorous standards of evidence and scrutiny.”

The hypothesis
that Diandongosuchus is more closely related to phytosaurs than to poposaurs originally appeared here in 2012 and was confirmed four years later by Stocker et al. That Dr. Marjanović does not approve of the earlier discovery tell us more about professional biases against ‘outsiders’, which we’ve seen before, than it does about the ‘coincidence’ he conjures.

 

References
Li C, Wu X-C, Zhao L-J, Sato T and Wang LT 2012. A new archosaur (Diapsida, Archosauriformes) from the marine Triassic of China, Journal of Vertebrate Paleontology, 32:5, 1064-1081.
Stocker MR, Nesbitt SJ, Zhao L-J, Wu X-C and Li C 2016. Mosaic evolution in phytosauria: the origin of longsnouted morphologies based on a complete skeleton of a phytosaur from the Middle Triassic of China. Abstracts of the Society of Vertebtate Paleontology meeting 2016.

 

Some things you learn are not found in any textbooks…yet.

No current discoveries are found in the latest textbooks. 
That’s because it takes time (years typically) for textbooks to be (in reverse order) assigned, accepted, distributed, printed, edited, written and illustrated, researched and concepted. Textbook publishers are out to sell the maximum number of books, so they write to the current consensus, which may be in flux on several points and hypotheses. The current consensus may also be wrong–but it remains the consensus.

There are no courses
at any colleges entitled, PTEROSAURS 101, 102 or 103. Who would attend? There are only two dozen people in the world who have an interest, who study them, or contribute to what we know about them. And where is the consensus? On some points, there is no consensus!! And all too often “the consensus” is holding on to outmoded, invalid and unverifiable paradigms (see below).

Every new fossil specimen is really a new chapter
in an ever expanding textbook on paleontology. And all paleontologists who publish are contributing authors to that future textbook.

Striiving for veracity
It is important for all workers to see things as they are in specimens, and not to reinterpret them to fit an established paradigm, no matter the temptation to do otherwise. For instance, narrow chord wing preservation in pterosaurs is not the result of ‘shrinkage’ as some workers report. Rather it is what it is, universal. All pterosaur specimens have narrow chord wings. If you know one that is different, please tell me. I know one that appears different, but that’s because part of its arm was ripped away and displaced. Look closely. That’s the way it is.

If Galileo
went to school as a teenager and found the following question on a test: “If object A at ten pounds and object B at 10 ounces both fall from 1000 feet at the precisely the same moment, how many seconds ahead of B will A strike the ground?” He’d would not have even had the opportunity to choose answer E. “zero seconds.” Common knowledge at the time, based on Aristotle, would not have allowed it, no matter the facts of this case, proven by experiment. This went on for centuries.

Similarly,
if you were in college today and were given the multiple choice question, “Which one of the following taxa is most closely related to pterosaurs? A. Dinosaurs. B. Scleromochlus. C. Proterochampsids (including Lagerpeton). D. Euparkeria. E. Erythrosucids. F. We don’t know.” You would have to pick “F” to get a good score, because that’s the current consensus… unless your professor had recently written a paper espousing one of the other answers (see below). “G. None of the above” is the better answer according to the large reptile tree where fenestrasaurs are more closely related to pterosaurs. But each one of the above (A-E) has been proposed by recent authors, not caring if they made sense or not.

Imagine the plight of the poor student in Paleontology 101 today
when he or she asks the professor about that website, “repitleevoluton.com” The professor is going to have to say, “If you want a good grade, you’ll ignore that website and provide the same answers that are in your textbook.” That’s what Dr. Darren Naish  reported online. Don’t consider, test or discuss other possibilities. Best to ignore them — if you want to advance in paleontology and get your Masters or PhD.

Take, as an example,
David Hone’s dissertation that was later published in two papers in which he proposed comparing two competing pterosaur origin hypotheses, one by Peters 2000 (Cosesaurus, Sharovipteryx, Longiasquama) and one by Bennett 1996 (Scleromochlus) using the supertree method of analysis (combining several published analyses without actually examining any fossil specimens). Aware that his professor, Michael Benton, had earlier written a paper (Benton 1999) celebrating Scleromochlus as the sister to pterosaurs, Hone decided to delete and diminish the taxa proposed by Peters. He somehow created several typos in the Peters data and then deleted the entire Peters dataset because of those typos (references and the full story here). Then Hone and Benton (2008) gave credit for both competing hypotheses to Bennett while deleting all reference to Peters 2000. As a result, Hone received his PhD, two associated papers (Hone and Benton 2007, 2008) were published and Hone gained the ability to referee pterosaur manuscripts (like mine) submitted to academic journals. I wrote to Dr. Benton about the inconsistencies and leaps of logic between the two parts of their two part paper. His reply was a sheepish, “whoops. :  )”

See how it works? 
That’s how you crush an opposing hypothesis. And that’s just the tip of the iceberg of current readily solvable problems, as Pterosaur Heresies readers are well aware. No PhD wants to admit he/she was wrong. On some problems consensus will likely never be achieved — because in order to do so all invalid candidate hypothesis writers would have to admit they were wrong.

And that’s just not going to happen.
Not without a fight or a dismissal. Let me know if you know of any instances of someone admitting they were wrong (I know of one semi-wrong situation regarding Dr. Padian and his fight with pterosaur tracks). In the origin of snakes, pterosaurs, turtles and dinosaurs there are lots of ‘right’ answers out there, but few challenges to the weaker hypothesis and no one admits to being wrong.

As history tells us, in paleontology it takes decades to turn the boat around. And paleontologists don’t want anyone else, even other paleontologists, solving their mysteries for them… even when solutions are published in the literature.

Thanks for your interest.
I will continue to study and make informed comment on new fossil specimens, (many that haven’t made the textbooks yet). I will throw a spotlight on problems and celebrate solutions as they are verified or not in the large reptile tree. And I encourage you to do the same. If I can do it, anyone can do it.

There are too many paleontologists who
follow
matrices, textbooks and papers blindly
and not enough paleontologists who have the balls to say, “Hey, there’s something wrong here.”

We’ll help fix the world of paleontology someday.
Unfortunately, it’s not going to happen this year. After four years of working with the large reptile tree, and improving it, and enlarging it year after year, it still has not been accepted for publication or gained intrigue among basal reptile workers. They don’t like it. It rocks the boat.

References
Bennett SC 1996. The phylogenetic position of the Pterosauria within the Archosauromorpha. Zoolological Journal of the Linnean Society 118: 261–308.
Benton MJ 1999. Scleromochlus taylori and the origin of the pterosaurs. Philosophical Transactions of the Royal Society London, Series B 354 1423-1446. Online pdf
Hone DWE and Benton MJ 2007. An evaluation of the phylogenetic relationships of the pterosaurs to the archosauromorph reptiles. Journal of Systematic Palaeontology 5:465–469.
Hone DWE and Benton MJ 2008. Contrasting supertree and total evidence methods: the origin of the pterosaurs. Zitteliana B28:35–60.
Peters D 2000. A Redescription of Four Prolacertiform Genera and Implications for Pterosaur Phylogenesis. Rivista Italiana di Paleontologia e Stratigrafia 106 (3): 293–336.

History of reptile Interrelationship hypotheses: Meckert’s PhD thesis

There is a long history
of workers creating hypotheses of reptile interrelationships going back to the mid 18th century (Carl von Linneaus 1758). That history, up until 1995 (Laurin and Resiz 1995 and Meckert 1995), was summarized by Dirk Meckert in his PhD thesis, which otherwise  concentrated on all available specimens of Barasaurus. You can download that thesis here online and read that short but fascinating history for yourself.

Some interesting notes arise from Meckert’s short history:

  1. Some studies united pareiasaurs and turtles. Others did not.
  2. Other studies united pareiasaurs, diadectids and procolophonids (which happened here just yesterday). Meckert wrote: “The Procolophoniformes contain Procolophonia and Testudinomorpha as sister-groups. Testudines are the sister-group of Pareiasauria within the Testudinomorpha.”
  3. Mesosaurs are commonly considered of uncertain affinities. But not here.
  4. Many prior studies had the synapsids branch off first. That is incorrect as shown here.
  5. No prior studies recognized the original dichotomy of lepidosauromorphs and archosauromorphs.
  6. No prior studies recognized Gephyrostegus bohemicus as a sister to the basalmost amniote.
  7. Diadectomorpha have been nested in and out of the Amniota. They’re in here.

No studies prior to reptileevolution.com
have included as many as 571 individual species as taxa, not counting the therapsid tree (with 52 additional taxa) and pterosaur tree (with 228 additional taxa) for a total of 851 taxa.

Other studies more recent than 1995
(not included in Meckert’s history) include

  1. http://www.palaeos.org/Reptilia and http://palaeos.com/vertebrates/amniota/reptiles.html
  2. http://whozoo.org/herps/herpphylogeny.html
  3. https://en.wikipedia.org/wiki/Amniote as determined by Benton, M.J. (2004). Vertebrate Paleontology. Blackwell Publishers. xii–452.
  4. University of Maryland (John Merck)
  5. online pdf, Amniote Origins and Nonavian Reptiles
  6. YouTube video by Walter Jahn
  7. Tree of Life
  8. Hedges 2012
  9. Gauthier, Kluge and Rowe 1988 online
  10. Hill 2005
  11. Mikko’s phylogeny archive
  12. ReptileEvolution.com
  13. Let me know if I missed any. I’ll add them here.

A while back
we looked at the differences between astronomy and paleontology. As noted earlier, time is never of the essence in paleontology — and that extends to idea acceptance. So many hypotheses of reptile interrelationships are still floating around out there. A definitive and all encompassing demonstration, like the large reptile tree, will probably just float forever with the other several dozen hypotheses out there, hashed, rehashed and rehashed again without end.

This is one of the frustrations of paleontology. And many think it is largely ego driven.

On that note
In astronomy the data, be it observation or spectral analysis, is immediate and widespread. You just have to look up with the right tool in the right direction. Or study the shared data (photos, etc.) Everyone can confirm the observation.

In paleontology the data comes out piecemeal, in low resolution, or imprecise tracings, not from every angle of view. Some key parts are lost and others are hidden beneath other bones or matrix. Sometimes you have to assemble dozens or hundreds of specimens for a proper study. No one is interested in confirming observations or analyses perhaps for years if ever. They’re all too busy with their own projects. Checking the characters and scores of an analysis can take weeks, months or years (as long as it took to build originally), and to do so requires the same amount of globe-hopping to see all the specimens in all the museums. No one is going to do that. They’d rather be making their own discoveries… and adding their taxa to established trees created by hungry PhD candidates, like Dirk Meckert in 1995, done at the nadir or advent of their experience.

The paleo-mantra remains: you must see the specimen!
And even that is no guarantee.

And if you want to break a paradigm or two,
like Ostrom did in the 1960s, you might have to wait for widespread (but never universal) acceptance. Paleontologists like their paradigms. They don’t like to give them up.

References
Benton MJ 2004. Vertebrate Paleontology. Blackwell Publishers. xii–452.
Carroll RL 1988. 
Vertebrate Paleontology and Evolution, WH Freeman & Co.
Laurin M and Reisz R 1995. 
A reevaluation of early amniote phylogeny. Zoological Journal of the Linnean Society, 113: 165–223.
Linnaeus C 1758. 
Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata.
Meckert D 1995.
 The procolophonid Barasaurus and the phylogeny of early amniotes. PhD thesis McGill University. Online Barasaurus dissertation

 

 

 

When Paleontologists Disagree: Who Do You Trust?

Gregrory Paul
(2002, figure 3.1; Fig. 1) published various illustrations of the skull of several specimens of the basal bird, Archaeopteryx, as restored by several paleontologists. You’ll note that these restorations are not identical. Paul also notes the inconsistencies bone-by-bone in his caption and he provides his own restorations in an effort to set the record straight. His book, Dinosaurs of the Air, is chock full of original art and text, well-researched and referenced.

Figure 1. Images from Paul 2002, figure 3.1) but flipped, rotated  and reordered.

Figure 1. Images from Paul 2002, figure 3.1) but flipped, rotated and reordered with permission.

For our purposes
it is enough to know that interpretations of paleontological data do differ from one professional worker to another. Every individual sees or traces something slightly different, depending on their level of precision and the experience they bring to the tracing. Many paleontologists, as we have seen, are not concerned with precision. It’s just not a priority.

Fossils are not preserved as blueprints.
Rather they have to be traced (choose your own method) then interpreted, skewed and rotated to produce straight dorsal and lateral views, as shown above, so they can be understood, compared and shared. Drawings are always done by hand (or mouse) and therefore unconscious bias, laziness, the effort to show something novel, and other human foibles always creep in, hopefully for the benefit of the reader whenever chaos is clarified.

So who do you trust?
For several decades most of us have trusted Gregory Paul over and above more than a few paleontologist illustrators with PhDs.

Wikipedia reports, “Paul helped pioneer the “new look” of dinosaurs in the 1970s. Through a series of dynamic ink drawings and oil paintings he was among the first professional artists to depict them as active, warm-blooded and – in the case of the small ones – feathered. Many later dinosaur illustrations are a reflection of his anatomical insights or even a direct imitation of his style. The fact that he worked closely with paleontologists, did his own independent paleontological research and created a series of skeletal restorations of all sufficiently known dinosaurs, lead many to regard his images as a sort of scientific standard to be followed.This tendency is stimulated by his habit of constantly redrawing older work to let it reflect the latest finds and theories.

“Paul lacks a formal degree in paleontology, but has participated in numerous field expeditions and has authored or co-authored over 30 scientific papers and over 40 popular science articles.”

Paul suggests that, “‘each paleoartist should produce their own skeletal restorations based on original research. This would include using photos of the skeleton, or an illustrated technical paper on the particular taxon.’ Paul has earned wide acclaim for this method.” 

Others have not earned wide acclaim by following Paul’s methods.

Darren Naish wrote
here: “Paul’s massive influence mostly comes from the fact that his reconstructions have always been based on an underlying, apparently empirical effort to depict anatomy. In an ideal world, all attempts to reconstruct fossil animals would proceed this way. Paul argued that one should strive to produce multi-view skeletal reconstructions of fossil archosaurs, and that a good understanding of the overlying musculature should result in a reconstructed form that – bar integument – is essentially that of the living animal. [there was] a time when certain palaeontologists decried the reconstructing of small dinosaurs as feathery or furry as wholly unscientific and as evidence of the obviously inferior intellect and experience of Paul and his artist colleagues, but look where we are now.”

Naish continues, “People like reading what Paul writes because he is well known for being controversial; for promoting new and sometimes daring and weird ideas about dinosaur evolution, biology, locomotion and behaviour. This is the person who was arguing for feathered theropods and fuzzy ornithischians before such ideas went mainstream, argued for the evolution of widespread secondary flightlessness across maniraptoran theropods, and worked to emphasise the idea that watching live dinosaurs would be like watching modern animals on the Serengeti – there would be dust in the air, interspecies conflicts, occasional herbivory in predators and occasional carnivory in herbivores.”

Naish further continues, “Some researchers say that the very raison d’etre of this work – Paul’s body of high-fidelity skeletal reconstructions – is problematic, with the underlying reconstructive process being subjective, prone to bias and misinterpretation, and far more artistic than Paul makes clear. Producing skeletal reconstructions of this sort involves extrapolation, interpretation and a degree of guesswork, so perhaps it would be helpful – and this is not a specific criticism of Paul, but one that could be directed at all technical skeletal reconstructions – if the reconstructions were framed as hypotheses where some (SOME, not all) of the details are open to alternative interpretations.”

On the downside,
quadrupedal plateosaur poses championed by Paul were disputed by Mallison 2010.

The beauty of Science is this:
everything that is presented, by Greg Paul, yours truly, or anyone else, can be tested by repeating the process yourself. Do the work and reap the rewards of discovery, confirmation and refutation. Paul saw things other experts had missed. He used his artistic talents to convey and share his insights so that others could appreciate dinosaurs as he saw them.

Now we all see dinos his way.

Thanks to Gregory Paul
for permission to publish his work (Fig. 1). Thanks also for his many novel insights, his devotion to precision, and for sharing with all of us a new paradigm for how dinosaurs looked, behaved and interacted.

References
Mallison, H. 2010. The digital Plateosaurus II: An assessment of the range of motion of the limbs and vertebral column and of previous reconstructions using a digital skeletal mount. Acta Palaeontologica Polonica 55, 433-458.
Paul G 2002. Dinosaurs of the Air: The Evolution and Loss of Flight in Dinosaurs and Birds. Johns Hopkins University Press, Baltimore. 406 pp.

wiki/Gregory Paul

Wikipedia ignoring published literature

I’ve had the honor and privilege
of having several of my manuscripts and figures published in academic journals. But when the authors of Wikipedia wish to describe pterosaurs or the various fenestrasaurs like Cosesaurus and Sharovipteryx all references to my work are deleted or ignored. Worse yet, when it comes to Longisquama, I and my work are described as’ idiosyncratic’ and “strongly denounced.” Such attacks are not found on the pages of other prehistoric reptiles and they don’t belong on the pages of Wikipedia.

Figure 1. Scene from "It's a wonderful life" directed by Frank Capra in which Clarence tells Jimmy Stewart, "You never were born." When the authors of Wikipedia ignore published literature on pterosaurs and fenestrasaurs, this is what they are trying to do.

Figure 1. Scene from “It’s a wonderful life” directed by Frank Capra in which Clarence tells Jimmy Stewart, “You never were born.” When the authors of Wikipedia ignore published literature on pterosaurs and fenestrasaurs, this is what they are trying to do. Click to view a few minutes from this movie.

So, it’s not enough
to view the fossils first-hand, pass peer-review and enter the literature. Evidently some observations, findings and workers are to be shunned, maligned and marginalized. It’s not the first time this has happened in the history of Science. And it probably won’t be the last.

I recently added
my work on pteroid origin and articulation (Peters 2009) to the Wikipedia page on pterosaurs. Let’s see how long it stays up. In the literature these observations and hypotheses have not yet been falsified or questioned, but confirmed.

References
Peters D 2009. A reinterpretation of pteroid articulation in pterosaurs. Journal of Vertebrate Paleontology 29:1327-1330.

 

Astronomy vs. Paleontology

Having dealt with astronomy and paleontology for much of my life, I thought it would be a good time to compare and contrast the two.

In astronomy 
all the members of the Cosmos are available to anyone to observe with or without a telescope. All the specimens are complete with regard to their visual spectra. Interpretation is straightforward and typically not controversial.

In paleontology
all the undiscovered specimens are available to anyone who puts in the effort to find them and remove or expose them from the matrix, but some specimens cannot be excavated without a permit. Some of the discovered specimens are available for study in museums. A few discovered specimens are kept in desk drawers and offices awaiting description or redescription and are therefore unavailable. Privately held specimens cannot enter the literature, but some do. Complete specimens are relatively rare. Most to all specimens need to be reconstructed from in situ data to their in vivo state, but this is rarely done. Some bits and pieces can be misinterpreted and interpretations can be controversial. Sometimes its hard to tell a suture from a crack. Some bones are buried beneath others or leave only the faintest impressions and stains.

In astronomy
all of the visible specimens follow the law of physics and so are largely predictable and follow paradigms set down decades ago. Dark energy and dark matter remain the only enigmas. The age of the Universe and distances to various heavenly bodies appears to be universally agreed upon. Mistakes rarely if ever occur any more. No specimens need to be reconstructed: WYSIWYG.

In paleontology
most of the specimens fall readily into established clades and can be identified as to their diet and niche. However several specimens and clades have been and continue to be misidentified as to their nesting. Mistakes continue to be made largely due to taxon exclusion, sometimes by oversight, sometimes by refusal. Many determinations are made by opinion and by following tradition rather than by rigorous testing.

In astronomy
anyone can discover a member of the Cosmos, and announce it to the Astronomical Union. Time is often of the essence. The pros don’t mind if an amateur makes a discovery. Every discovery is celebrated.

In paleontology
if you discover something you have to write a paper, then submit it, then wait about six months for referees to review it, then go through the editorial process if accepted, then await its ultimate publication, often a year later. Time is never of the essence. Even so, anyone can make a contribution, if deemed acceptable, The pros don’t like amateurs making discoveries that they should be making. After all, something can only be discovered once. Some discoveries are shunned and ignored.