Sunday, June 10, 2018

Review: "Beasts of the Mesozoic" Tsaagan by Creative Beast Studios

Quick Facts
2018 Beasts of the Mesozoic Raptor Series Tsaagan mangas action figure
Size: 20cm long
Scale: 1:6
Sculpted by: David Silva
Produced by: Creative Beast Studios

Back in April 2016, toy industry veteran David Silva launched a Kickstarter campaign to produce scientifically accurate "raptor" (eudromaeosaur) figures. Unlike the vast majority of static PVC dinosaur figures on the market, these would be super articulated, with up to 24 joints allowing significant posability. Now, over two years later, the project has become a reality, and my selection of a Wave 2 Tsaagan mangas figure has finally arrived. So, how does it stack up to the high expectations and lofty claims that these are the most scientifically correct dinosaur action figures on the market?

Friday, May 4, 2018

The Step-wise Bird: Andrea Cau on Bird Evolution

Above: WIP reconstrcution of one potential Connecticut River Valley trackmaker, the bird-like reptile Anchisaurus polyzelus. By M. Martyniuk, all rights reserved.
This morning saw the publication of a new paper by Andrea Cau, titled Assembly of the Avian Body Plan, and what a mammoth (dinosaurian?) work it is! Cau does an amazing job of synthesizing the step-wise nature of bird evolution that is so often hidden behind imprecise or muddy nomenclature. Far from a dichotomy between "non-avian" and "avian" dinosaurs, the important features we associate with modern birds gradually accumulated in a particular lineage of stem-birds ever since the early Triassic period. I should have a lot more to say on the nitty-gritty of this paper this weekend after I've had a chance to fully digest this important work on avian origins. In the mean time, I wanted to share a brief excerpt from (one of) my upcoming book(s), this one dealing with the struggles to interpret some of the earliest known dinosaur remains in an era before the nature of dinosaurs as weird transitional members of the bird lineage was fully understood. The chapter this comes from is discussing Edward Hitchcock's work in the early-mid 1800s on bird-like footprints found in the Connecticut River Valley. The footprints date to the early Jurassic (Cau's "Huxleyan stage" of bird evolution).

Several, more prominent, scientists of the time criticized Hitchcock’s interpretation of the footprints as having been made by birds. He was ridiculed for imagining huge birds that must have been many times the size of the largest living bird, the ostrich. Soon, the rediscovery of giant extinct birds like the moa granted him some level of vindication. But more serious criticisms followed. The sandstone of the Connecticut River Valley was simply too old, other scientists argued. Birds, being “higher” life forms in the ranked scheme of life most believed in at the time, must have also been newer, having developed fully only after the so-called “age of reptiles”. Some scientists went so far as to argue that the three-toed tracks belonged to giant frogs, and that only the large, strong hind limbs left impressions while the lighter forelimbs often did not. And, indeed, one fact which was very inconvenient to Hitchcock’s explanation was that some of the tracks preserved light forelimb impressions, and some were found along with tail drag marks.

What could Hitchcock do to save his bird hypothesis from the facts? By 1861, the discovery of an archaic proto-bird named Archaeopteryx lithographica provided the answer. Here was an example of a “bird” with primitive, reptilian features and a long tail. Perhaps, Hitchcock suggested, his sandstone prints were not made by giant moa-like birds, but giant Archaeopteryx-like birds. And what of the occasional forelimb impressions? Hitchcock actually suggested that, along with its primitive skeletal anatomy, the Archaeopteryx may have been a facultative quadruped! In his view, the Archaeopteryx was halfway between birds and reptiles in both anatomy and gait. Hitchcock had, rather unscientifically, crafted his hypothesis to be immune to all criticism. His peers weren’t buying it.

By the time of Hitchcock’s death in 1864, the bipedal, bird-like nature of many Mesozoic reptiles like Hadrosaurus and Compsognathus had been discovered. For most scientists, these creatures provided a more plausible explanation for Hitchcock’s “sandstone bird” tracks than actual birds. By the late 1800s, the tracks were universally accepted as having been made by prehistoric reptiles, though intriguingly bird-like ones. Today, we know that these ancestrally bipedal reptiles, the dinosaurs and their kin, did indeed have more in common with modern birds than with any of the modern reptile groups, and in fact included the evolutionary ancestors of true birds.

In the end, it turns out that Hitchcock was half-right. His sandstone bird tracks were made by creatures in many ways more like Archaeopteryx than any modern bird or reptile, some of which were partly or fully quadrupedal, with great sweeping tails and enormous body sizes compared to any birds alive today. Many of them even had feathers and feather-like filaments covering parts of their bodies. What Hitchcock had actually discovered were the bird-like reptiles, creatures descended from the same ancestors as crocodiles and turtles, but which had evolved a wide array of uniquely avian features. At a time when most mainstream scientists envisioned dinosaurs as huge, quadrupedal, mammal-like reptiles (in appearance and gait if not lineage), Hitchcock was able to use the traces they made in life to arrive at a conclusion that was actually much closer to the truth in many ways. The Mesozoic was not an “age of reptiles”, at least not on land. It was an age dominated by the bizarre, archaic relatives of birds.

I think the above is a good example of Cau's thesis that a false, dichotomous paradigm, like "bird" vs. "reptile", or "non-avian dinosaur" vs. "bird", and focusing mainly on "key" specimens like Archaeopteryx, can actively mask the reality behind fossil evidence. What do you think?

Sunday, April 30, 2017

Review: Dino-Riders Struthiomimus by TycOMG IT HAS FEATHERS

Quick Facts
1988 Dino-Riders Struthiomimus action figure WITH FEATHERS. IN 1988.
Size: 20cm of feathered glory.
Scale: Scales on the feet, feathers up top. Also, 1:12.
Sculpted by: The wokest of all 1980s dinosaur toy sculptors.
Produced by: Tyco (obviously with a lot of help from Bob Bakker).

No need to adjust your TV sets folks, this is a mass-produced dinosaur toy made in 1988 that is covered in feathers. Not like lame, Primal Carnage, Jurassic Park 3, cool-guy dragon with a mohawk. Natural looking feathers.

This is why Dino-Riders was the best thing about the '80s (sorry, He-Man). Dino-Riders gave us aliens from the future riding armored mind-controlled dinosaurs blasting a thousand lasers at other armored dinosaurs who were not mind controlled but who were just in it because they cared about justice, and the toy versions of these things looked more naturalistic and scientifically accurate (for the time) than anything in Jurassic World.

I'm going to use this particular review to drop some history.

Wednesday, April 12, 2017

You're Doing It Wrong: Pteranodon Bills

Your bill's looking a little puny, there, buddy.
(Painting by Heinrich Harder, 1912, public domain).
Everybody knows Pteranodon. Quick, stop to imagine it! It's easy, because it's the most often-illustrated and well known pterosaur to the general public (though today's marketing departments often call it a pterodactyl, following it's original, century-out-of-date classification).

But hold on. That image you have in your head right now, of a big pterosaur with a long crest and a mid-length pointy beak? That's likely wrong, and may be just as much a hybrid as those Flintstones-style creatures with pteranodont crests and Rhamphorhynchus tails.

How do we know? Let's talk about Dawndraco.

Wednesday, April 5, 2017

Review: Dino-Riders Pterodactyl by Tyco

Quick Facts
1987 Dino-Riders Pterodactyl action figure
Size: 20cm (wingspan)
Scale: 1:3 or 1:4
Sculpted by: unknown
Produced by: Tyco

Pterodactylus antiquus has a special place in history as one of the first ever prehistoric reptiles to be subjected to scientific study. It's one of the best known pterosaurs, with many complete specimens known to science, and it ended up lending its name to the entire group of pterosaurs to which it belongs (Pterodactyloidea). In fact, "pterodactyl" has become a common nickname for all pterosaurs, thanks in part to the fact that nearly all pterosaurs were considered species of Pterodactylus during the 19th century.

Despite the importance of pterodactyls, very few toy versions of them have been produced (in fact I don't know of any other than this one and one made by Starlux - if you know of more, let me know in the comments!). Sure, there are lots and lots (and LOTS) of toys out there claiming to be "pterodactyls", but the vast majority of these are actually other species of pterosaur, most often Pteranodon. A lot of older "pterodactyl" toys from the 1950s - 1980s are weird hybrids of the Pterosaurs' Greatest Hits, like pteranodonts with teeth, or with Rhamphorhynchus tails. But almost none of them are the classic, the original, the one and only pterodactyl. That's probably not a coincidence or a mistake - like the "velociraptors" in Jurassic Park that were really Deinonychus, pterodactyls have a cool name attached to a somewhat wimpy animal. Most pterodactyl fossils are tiny, with wingspans of only a few feet. Larger specimens do exist, but these skin-winged critters don't seem to have grown any bigger than a large seagull. Personally, I think that's part of their charm - I can't help but picture flocks of them squabbling over dead squids any time I watch gulls at the beach. But in terms of raw awesomeness, they certainly can't compete with 20 foot beasts like Pteranodon.

One of the very few pterodactyl toys that's actually a REAL pterodactyl is this one from Tyco. Produced in 1987 and released in 1988 at part of the Dino-Riders line, this pterodactyl came with a 2" action figure and a little hang glider accessory, but I won't be worrying about those here. Despite it's age, this is still one of my favorite pterosaur toys and holds up reasonably well even today. Let's get into some details...

Monday, July 18, 2016

Playing with Saurian's Genericometer

There's a dinosaur game in development called Saurian. Have you heard of it? You should really check out! It's shaping up to be super cool and extremely rigorous when it comes to science and coming up with accurate portrayals of an extinct ecosystem. Check out their page!*

*Full disclosure: I may be involved in this game's development in some small capacity. There will be birds.

The Saurian developers have made a somewhat controversial choice when it comes to the name of the Hell Creek Formation hadrosaurid. Yes, boys and girls, a video game company has dipped its toe into the boiling caldera that is dinosaur nomenclature.  Many fans (and keep in mind these are people who know enough to be early backers of a game priding itself on scientific accuracy and technical minutiae) were a little shocked to see the announcement of the Saurian hadrosaurid. Not just at the unbelievably painstaking level the devs went to in order to research and create the character - everything from life history and growth trajectories to mapping out the actual pattern of scales found on an infamous fossil mummy. People were also a little put off by the fact it was named Anatosaurus annectens rather than Edmontosaurus annectens.

I'm not going to re-hash the long and convoluted history of everybody's favorite "trachodont" (Wikipedia does a pretty good job of that). For the purposes of this post, it's enough to understand that these two species of dinosaurs, Anatosaurus annectens and Edomontosaurus regalis, are fairly similar. So similar that for the past 25 years or so, most scientists have "lumped" them together under the same group of species, the genus Edmontosaurus, making the binomial of the Hell Creek Formation species Edmontosaurus annectens and relegating the name Anatosaurus to the trash heap of history.

But, a few years ago something changed. See, there was a second Hell Creek hadrosaurid, a bigger and much more different looking beast named Anatotitan copei. During the same 25 year period, mostly everybody has agreed this dinosaur was different enough from its relatives to deserve its own genus name. Recently, studies have demonstrated that those differences aren't necessarily due to being more distantly related, but just being... older. Anatotitan, it turns out, is just a mature version of Anatosaurus/Edmontosaurus annectens that had built up more unique features with age. It's not just a similar species to annectens, like Edmontosaurus reglais is, it's the same species. So onto the trash heap with Anatotitan.

But wait! Anatosaurus was thrown out because it was too similar to Edmontosaurus. Now, it turns out, it was actually different--different enough that its adult form was given its own genus for all those years. So shouldn't Anatosaurus be a genus again?

Well, that depends on what you mean by "genus". There is no universally recognized rationale for what makes something "different enough" to be a genus, and the concept varies wildly between fields of biology. Each scientist has their own opinion, their own gut feeling based on tradition and intuition, not science, of what a genus should be. If you asked an entomologist to re-classify all dinosaurs based on her own personal "genericometer" settings, we'd end up with one single genus of dinosaur, and it would include every bird that ever lived. Probably crocodiles too. We'd be left arguing, based on page priority or something, if the star of Jurassic Park should be called Passer rex, Vultur rex, or Crocodylus rex. On the flip side, if you had a ceratopsian worker reclassify the beetles, we'd end up with a hundred billion new genera of beetle.*

*I'm not 100% sure that's the correct number, but it'd be something with a lot of zeroes.

Some people have attempted to bring some science to the art of taxonomy, and quantify genera. Recently and most famously, Emanuel Tschopp and colleagues published their precise genericometer settings, and used those settings to reclassify the diplodocid sauropods. This resulted in bringing back the old, previously-junked genus name Brontosaurus (you may have heard of it). This is a great thing to try, but the method was only designed to apply to diplodocids. It might wreak havoc with names in other dinosaur groups, and would certainly result in an entomologist revolt if anybody ever tried to use it on bugs.

To their credit, the Saurian team have been up front with their genericometer settings used in the game. Rather than base their concept of genus completely on anatomical similarity, they've made the very intriguing choice of combining evolutionary relationships with a chronological component. Basically, if species B is the closest relative of species A, and if species B is known from fossils that can be dated to within one million years of species A fossils, then species A and B are to be classified in the same genus.

I thought it would be fun to try out these genericometer settings and see how it compares to the current traditional consensus, and to some other more widely criticized attempts to re-genericize dinosaurs, like the classification used by Greg Paul in his Princeton Field Guide to Dinosaurs.

Edmontosaurus vs. Anatosaurus.

We'll start with Anatosaurus. If we take Anatotitan to be its synonym, then according to most recent phylogenies, its closest relative is Edmontosaurus regalis, which lived more than a million years earlier. This is why Saurian chose to split Anatosaurus back off into its own genus. But right here, we immediately need to note how highly dependent on the vagaries of phylogenetic analysis this method is. Ugrunaaluk is a very similar hadrosaurid that actually lived in between Edmontosaurus and Anatosaurus, and was originally thought to represent specimens of Edmontosaurus. According to the (very few) phylogenetic analysis on its relationships, Ugrunaaluk is actually outside the Anatosaurus+Edmontosaurus clade. But, given its chronological position, it's always possible more analysis will show that it is transitional between them. Ugrunaaluk is still too old to connect Anatosaurus to Edmontosaurus by a million years or less, but only slightly. Ugrunaaluk lived about 69 Ma ago, and the earliest Anatosaurus fossils are about 67 Ma old. All it would take would be one slightly younger Ugrunaaluk specimen, in that case, to pull the whole shebang back into Edmontosaurus.

Following this cladogram for the sake of argument, let's look at the next outgrip to Edmontosaurus, which is the clade Saurolophini. Now we reach the sticky question of what counts as the next closest relative of Edmontosaurus, moving down the tree. So lets start at the tip of the next branch, with Saurolophus. S. osborni lived between about 69-68 Ma ago, slightly later than the last Edmontosaurus, but still within a million years. S. angustirostris lived about 70 Ma ago, during the time Edmontosaurus was alive. Prosaurolophus lived up until around 74 Ma ago, which predates Saurolophus but sits just barely within a million years of the lower range of Edmontosaurus. Since both Saurolophus and Prosaurolophus lived within a million years of the upper and lower range of Edmontosaurus, following these genricometer settings, they should all be lumped into a single genus. Because of the rules of priority, that means Edmontosaurus itself goes on the trash heap and Saurolophus regalis becomes the correct name for that species. Same for the next closest relative to the Saurolophus + Edmontosaurus group, Gryposaurus, which is within a million years of Prosaurolophus. Ditto Kritosaurus. It's not until the Brachylophosaurini clade that we finally get a break from all this lumping, but already, half of the short-crested hadrosaurids are now Saurolophus.

Obviously, I'm taking this a little far on purpose, just to test it out as a general-use genericometer for dinosaurs. You could easily tweak these settings to produce more traditional genera, like adding a rule against paraphyly (both Anatosaurus and Kerberosaurus would fall within a clade formed by members of Saurolophus in the above example; though in my opinion this is a feature rather than a bug, since some genera had to have evolved from others anyway, it's a little silly trying to rigidly keep them monophyletic). We could also add a stipulation that the time component is relative to the type species or, even better, type specimen, to allow for inevitable evolutionary grades from one form to another. This would, in effect, place a sort of million-year "radius" around a species that is not ever-expanding. So anything up-tree or down-tree of E. regalis, like Ugrunaaluk, gets caught in its gravity well, but we don't then jump to anything within a million years of Ugrunaluuk, too. I have to think this is probably the real intent of the Saurian team's method.

A variety of ceratopsid genera, by Danny Cicchetti (CC-By-SA).
"These are all different GENERA? That's hilarious," --Entomologists.

Using this type-restricted genericometer method could still do some fun things in the one part of the dinosaur tree that everybody sort of secretly thinks is horribly over-split but doesn't say so out loud because nobody really wants to rain on those guys' big ol' naming party: the ceratopsids.

The Saurian team stated that, if they were to include Torosaurus as a distinct species in the game, it would be as a species of Triceratops, per the genericometer settings described above. Following this cladogram and a type-restricted interpretation of Saurian's method, Torosaurus does become a species of Triceratops, the holotype of which is from about 67 million years ago. Nedoceratops has to go as well. Now, the Triceratops party ends there based on this particular cladogram, but I find the placement of the Titanoceratops a little er... iffy. Titanoceratops is really, really similar to Pentaceratops from almost the same time and place, so finding it in between a bunch of species that look basically identical to Triceratops is odd. I'm not saying it's wrong, but let's just ignore it for the moment. If we do, then Ojoceratops, Eotriceratops, and Regaliceratops all become species of Triceratops, too. So the entire clade Triceratopsini = Triceratops.

Further down the tree, we have Anchiceratops and Arrhinoceratops becoming synonyms. Kosmoceratops and Vagaceratops, too. Chasmosaurus subsumes Mojoceratops, Agujaceratops, Utahceratops, and Pentaceratops. Coahuiloceratops and Bravoceratops are both safe, and form the sister clade to the big Chasmosaurus complex.

On the centrosaurine side of the tree, Achelousaurus becomes Einiosaurus, unless paraphyly is invoked. Centrosaurus gobbles up Coronosaurus, Spinops, and Styracosaurus (again, unless paraphyly is invoked, in which case Styracosaurus remains valid but includes Rubeosaurus ovatus; this was the plan for one of the unmet Saurian Kickstarter stretch goals that would have included Styracosaurus ovatus).

Overall, this system produces a classification that is similar to, but not nearly as extensively lumped, as the one used by Greg Paul. I kind of like it, especially with the type species stipulation in play. I think that if you are going to use genera, and not just convert all genus names to species praenomen as some people have suggested, it's a good idea to have some kind of standard metric. The problem is, of course, that nobody will ever agree to one standard. Even within dinosaurs. Nobody specializes in all dinosaur groups. We have ceratopsian workers, tyrannosaur workers, avialan workers, sauropod workers, etc., all with their own traditions and personal metrics. This is why it tends to be the science popularizers, like the Saurian devs or Greg Paul or even Bob Bakker, who are the ones coming up with what all the professionals view as highly idiosyncratic classifications. They're attempting to take all these disparate fields within dinosaur paleontology and apply a single metric to all of them, which is bound to change a few things away from the consensus.

At the end of the day, the consensus is what it is. I'm glad people are exploring ways to apply consistency and standards to science-related minutiae like taxonomy. But it's equally important that those efforts be transparent, so we can compare each metric to the others and see which produces the results we like the best. Because at the end of the day, all of this splitting and lumping of genera comes down to just that: a matter of opinion.

Saturday, May 28, 2016

You're Doing It Wrong: Microraptor Tails and Mini-Wings

Type specimen of Zhenyuanlong, doing its best Archaeopteryx impression.
Just a short PSA today, and once again, it's about a paleoart meme that has outstayed its welcome.

Microraptor was the first time we got a good look at the feather pattern of dromaeosaurids. This is a big problem for two reasons. One, microraptors were small. That means that artists who were looking at them to extrapolate for bigger, more famous "raptors" could easily and somewhat justifiably write off their huge wings as a product of their size. Sure, we thought, microraptors had big wings, but they're tiny animals. Surely the bigger, more terrestrial dromaeosaurids didn't need such big wings. They probably still had wings, but they'd be smaller. Why would Velociraptor need such proportionately huge wings if it couldn't fly or glide?

Meme number two: that tail. I admit to being one of the first to go overboard when I fell, head over heels, for the "puff tailed dromeosaur" fossil (now the holotype of Cryptovolans, a synonym or close relative of the Microraptor) back around 2000. This was the first evidence we had of the tail feather style in dromeosaurids (or evidence that they even had remixes and rectrices at all. Remember When Dinosaurs Ruled America? That was plausible at the time it was being made). Naturally, having Microraptor plus Caudipteryx showed that the ancestral condition of pennaraptorans was a fan of feathers at the tip of the tail, not a fuzzy Sinosauropteryx like tail or a fully-vaned Archaeopteryx like tail. So artists ever since have been drawing dromeosaurids and troodontids and oviraptorosaurs with microraptor tails.

But that turned out to be wrong! It's an accident of history. We're now learning that Microraptor and Caudipteryx are weirdos.