The Dinosaur Thread

[Yowza]

I wonder how many of the Carnivores had a toxic bite similar to the Komodo dragon?

The Megalania is a distant relative of the Komodo said to be larger and roamed Australia 40000 years ago is the largest toxic predator known as mentioned in this link describing recent additional discoveries concerning Komodo Dragon's Toxin:

Komodo Dragons Kill With Venom, Researchers Find
Komodo dragons kill using a one-two punch of sharp teeth and a venomous bite, scientists have confirmed for the first time.

The find dispels the common belief that toxic bacteria in the Komodos' mouths are responsible for ultimately killing the dragons' prey.

An animal that escapes a Komodo's initial attack soon weakens and dies. The fierce carnivore tracks the wounded creature and dines at its leisure once the prey collapses.

Researchers have long thought that the Komodo dragon, native to Indonesia, kills via blood poisoning caused by the multiple strains of bacteria in the dragon's saliva.

But "that whole bacteria stuff has been a scientific fairy tale," said Bryan Fry, a venom researcher at the University of Melbourne in Australia.

Fry and colleagues studied the biochemistry of Komodo venom after they had the rare opportunity to examine two dragons from zoos that both had to be put down due to terminal illnesses.

The team found that the dragon's venom rapidly decreases blood pressure, expedites blood loss, and sends a victim into shock, rendering it too weak to fight.

In the venom, some compounds that reduce blood pressure are as potent as those found in the word's most venomous snake, western Australia's inland Taipan.

Komodo Combo Attack
While his colleagues expressed surprise at the findings, Fry said he wasn't so shocked.

His earlier research had shown that other lizard species—such as iguanas, legless lizards, and monitor lizards—are also venomous.


In fact, Fry estimates that close to a hundred of the more than 5,000 known lizard species use venom.

What is surprising, Fry said, is Komodo dragons' elaborate venom-delivery system.

"It's the most complex duct system described in reptiles to date," he said.

Snakes typically have a single venom duct that leads to their fangs. But Komodos have multiple ducts located between their teeth.

However, this means Komodo dragons don't deliver their venom as efficiently as snakes, Fry said.

Rather than injecting venom directly via a forceful bite, the dragons use a specialized bite-and-pull motion to ooze the toxin into wounds during a sustained, frenzied attack.

(Related: "Komodo Dragon's Bite Is 'Weaker Than a House Cat's.'")

The combination of venom and multiple lacerations from the lizards' sharp, serrated teeth is what makes the dragons so deadly.


"They're not like the cobra, where venom is the only game in town. Komodos have a combined arsenal," Fry said.

The findings suggest that the Komodo's ancient relative, the Megalania, used a similar venom-plus-wounding approach.

The giant lizard, which roamed Australia about 40,000 years ago, measured about 13 feet (4 meters) long.

Fry's work, published in this week's issue of the Proceedings of the National Academy of Sciences, could mean that the Megalania was the largest venomous animal to have ever lived.

More on Megalania:






The Current Komodo Dragon:

Some things I've noticed about this creature watching some nature videos on it just recently:
*There's some interesting videos I just found on Youtube concerning the current Komodo Dragon (way more deadly and quick than they look as seem kind of puppet like the way they saunter about but can run up about 12 mph doing a beeline over a decent distance). There's some that are so graphic I probably shouldn't post a link to it here but involves a deer essentially immobile due to the poison being slowly eaten alive. A pretty bad way to go.

*There's another youtube video ("Live Deer Ripped Apart By Komodo Dragons" it's called) of a crowd of them essentially all feasting on a live deer at once also too graphic to link to. You can literally hear the sounds of them crawling over each other to get to the deer and don't even bother chewing on the torn chunks but just inflate their necks and swallow it whole never being satiated seemingly as they can eat up to 80% of their body weight.

*There's another video of one biting a water bison then a bunch more casually coming out of the bush watching it for however long it takes as it slows down. Or, there's a separate video of a Komodo simply killing a smaller goat by catching it and bringing it down then a couple more appear out of nowhere and there's nothing left. Supposedly they can eat 80% of their body weight and horf down bone, cartillage, and everything down that long neck of their's sitting in belly almost the size of the animal itself. Even a small Komodo could probably horf down a human leg or arm quite easily.

*Their venom is so toxic there's now some disagreement on whether it's the 50 strains of bacteria from the sewer reservoir inside their gums between their teeth that wells up from when the jaw applies pressure around something grinding it with serrated teeth or another kind of venom as described in link above that simply causes the blood pressure to crash and leave one unable to fight back or move going into shock within a few hours for a human. The way they hunt can be seen under a Youtube video entitled "Powerful Komodo Dragons Observed Hunting In the Wild". This is also graphic in some parts but mainly focuses on the film crew spinning in circles with sticks in hand watching as more Komodo's keep showing up to a feast.

*They're quite a nightmare to deal with and can smell blood from 5 miles away. One would have to be turning in a circle constantly stick in hand ready to fend some off as they're very sneaky and quick especially if close by and so many popping out of no where honing in on whatever's in the scent area. In fact they've been known to dig up human graves by some accounts.

*They can be cannibalistic. So ravenous there's a nature photo I found online of a smaller one sticking it's head into the mouth of a bigger one to snatch it's food out. Komodo dragon sticks its head inside another one’s mouth to snatch its food | Daily Mail Online

*They're quite heavy as can be seen in videos of them fighting and hissing at one another. About 150-200 lbs typical but smaller ones can come out of nowhere and bigger ones said to be about 300 lbs too. Including tailspan 10 ft is typical. Komodo Dragon (Varanus komodoensis) | about animals and

 

[jolldan]

Argentine scientists discover new dinosaur species

 

[Flash525]

It always fascinates me when a new Dinosaur is discovered, simply because I often wonder how anyone knows it's new, rather than existing, or deformed, and yet when you think of how many species of animal roam the world today, and further, how many have roamed since the Dinosaurs, you'd think there's still many species of Dinosaur, hundreds in fact, that remain undiscovered.

 

[jolldan]

It always fascinates me when a new Dinosaur is discovered, simply because I often wonder how anyone knows it's new, rather than existing, or deformed, and yet when you think of how many species of animal roam the world today, and further, how many have roamed since the Dinosaurs, you'd think there's still many species of Dinosaur, hundreds in fact, that remain undiscovered.

Yeah probably dozens if not hundreds at the bottom of the oceans.

 

[Kahran Ramsus]

It always fascinates me when a new Dinosaur is discovered, simply because I often wonder how anyone knows it's new, rather than existing, or deformed, and yet when you think of how many species of animal roam the world today, and further, how many have roamed since the Dinosaurs, you'd think there's still many species of Dinosaur, hundreds in fact, that remain undiscovered.

I think it is safe to say that there are far, far more dinosaurs that we haven't discovered than that we have. A lot has to go right for us to discover them. They have to fossilize properly. Then that rock has to be exposed at the surface so we can actually find it. There is a reason most of the discoveries occur in the same few places. There is a whole lot of land out there that's the wrong age for dinosaurs (not going to be finding too many dinosaurs in Ordovician rock) or is from an environment that was ill-suited for the fossilization process.

 

[Melpardus]

I wonder how many of the Carnivores had a toxic bite similar to the Komodo dragon?

The Megalania is a distant relative of the Komodo said to be larger and roamed Australia 40000 years ago is the largest toxic predator known as mentioned in this link describing recent additional discoveries concerning Komodo Dragon's Toxin:
More on Megalania:






The Current Komodo Dragon:

Some things I've noticed about this creature watching some nature videos on it just recently:
*There's some interesting videos I just found on Youtube concerning the current Komodo Dragon (way more deadly and quick than they look as seem kind of puppet like the way they saunter about but can run up about 12 mph doing a beeline over a decent distance). There's some that are so graphic I probably shouldn't post a link to it here but involves a deer essentially immobile due to the poison being slowly eaten alive. A pretty bad way to go.

*There's another youtube video ("Live Deer Ripped Apart By Komodo Dragons" it's called) of a crowd of them essentially all feasting on a live deer at once also too graphic to link to. You can literally hear the sounds of them crawling over each other to get to the deer and don't even bother chewing on the torn chunks but just inflate their necks and swallow it whole never being satiated seemingly as they can eat up to 80% of their body weight.

*There's another video of one biting a water bison then a bunch more casually coming out of the bush watching it for however long it takes as it slows down. Or, there's a separate video of a Komodo simply killing a smaller goat by catching it and bringing it down then a couple more appear out of nowhere and there's nothing left. Supposedly they can eat 80% of their body weight and horf down bone, cartillage, and everything down that long neck of their's sitting in belly almost the size of the animal itself. Even a small Komodo could probably horf down a human leg or arm quite easily.

*Their venom is so toxic there's now some disagreement on whether it's the 50 strains of bacteria from the sewer reservoir inside their gums between their teeth that wells up from when the jaw applies pressure around something grinding it with serrated teeth or another kind of venom as described in link above that simply causes the blood pressure to crash and leave one unable to fight back or move going into shock within a few hours for a human. The way they hunt can be seen under a Youtube video entitled "Powerful Komodo Dragons Observed Hunting In the Wild". This is also graphic in some parts but mainly focuses on the film crew spinning in circles with sticks in hand watching as more Komodo's keep showing up to a feast.

*They're quite a nightmare to deal with and can smell blood from 5 miles away. One would have to be turning in a circle constantly stick in hand ready to fend some off as they're very sneaky and quick especially if close by and so many popping out of no where honing in on whatever's in the scent area. In fact they've been known to dig up human graves by some accounts.

*They can be cannibalistic. So ravenous there's a nature photo I found online of a smaller one sticking it's head into the mouth of a bigger one to snatch it's food out. Komodo dragon sticks its head inside another one’s mouth to snatch its food | Daily Mail Online

*They're quite heavy as can be seen in videos of them fighting and hissing at one another. About 150-200 lbs typical but smaller ones can come out of nowhere and bigger ones said to be about 300 lbs too. Including tailspan 10 ft is typical. Komodo Dragon (Varanus komodoensis) | about animals and

Well Komodo dragons are just venomous; the notion of them having toxic bacteria lurking in among their teeth is a bit of an outdated notion at this point, as some of the sources you mentioned state. Their mouths aren't objectively much dirtier than any other tetrapod's. On that note, a couple things I'd like to point out:

1. It turns out that all monitor lizards (aka varanids) are venomous to some degree, so Komodo dragons aren't alone in this regard, although they don't seem to be especially potent, at least as far as humans are concerned. People who get bitten by smaller pet animals tend to report a burning and maybe some swelling, but otherwise it's usually not that bad.
2. As an extension, varanids are part of a whole clade of venomous reptiles called Toxicofera, which includes not just varanids and snakes but also iguanas, chameleons, and agamids. Whether all of these animals actively use their venom (if they still have it) and to what degrees is unclear, especially since the methods of hunting and the food they eat often precludes the necessity for some sort of incapacitating agent, but they all apparently have the genes to at least produce it. Extra extension, this group also includes mosasaurs, so there's one group of extinct ancient reptiles that might've been venomous as well.
3. There's evidence of potential venomous capacities in a group of Permian-Triassic-aged synapsids (the group that includes mammals) called therocephalians, particularly Euchambersia.

Also, about a month late but this year is the 20th anniversary of Walking with Dinosaurs, and there's a couple interesting retrospective YouTube video series/reviews on it that those in this thread might find interesting.

• Sam the Giganfan has fairly brief review (about ~15 minutes) and just recaps each episode; it overall focuses more on the storytelling elements rather than the science itself. He also has reviews of all the sequels and spinoff programs (the rest of the Walking with... series and the Chased by... series) if you want to check those out too.
• Henry the PaleoGuy's review does the same thing as the above but fleshes out the analysis with more in-depth science stuff regarding how the creatures are depicted compared to both then-contemporary and modern knowledge. As such it's about 35 minutes but it's a good all-around video.
• Ben G Thomas is my personal favorite of the three; the videos are the most in-depth of the ones I've linked to since each episode of the program gets its own 20-30 minute video that pretty much ignores story analysis and just delves into the science of the creatures and their habitats. So far they've only covered the first two episodes but this is definitely the series I'd recommend the most out of the three. I've definitely learned the most from it.
• As a humorous and extra nostalgic bonus for those of a certain age, I'd recommend this:

Finally, just wanted to bring attention to two new pieces of paleoart:

• RJ Palmer's (of realistic Pokémon and Detective Pikachu fame, and one of the concept artists on the in-development video game Saurian) new Allosaurus reconstruction:
• and a new T. rex model for the new Field Museum exhibit, based on "Sue":

 

[:eek:]

'Reaper of death,' newfound cousin of T. rex, discovered in Canada | Live Science

 

[Melpardus]

Tyrannosaur names are so unnecessarily edgy as of the last year or two; it makes it even more ironic and mildly eye-roll inducing that most of them just end up being really fragmentary and on the relatively smallish side. Also, very curious why this discovery is only just now making headlines; the description paper has been out for a couple weeks now. I'd argue that this new study from last month about Tarbosaurus teeth is much more significant as far as tyranosaur stuff is concerned, as it provides detailed evidence of the species' dietary preferences down to the individual as well as information on the seasonal climate and rainfall patterns of the Mongolian Nemegt Formation. Not as important but still significant, yet another nail in the coffin for "Nanotyrannus": Growing up Tyrannosaurus rex: Osteohistology refutes the pygmy “Nanotyrannus” and supports ontogenetic niche partitioning in juvenile Tyrannosaurus

In other paleo news, a new species, Allosaurus jimmadseni, was formally described last month, bringing the official Allosaurus species count to 3. The paper reassigned a bunch of specimens formerly unclassified or considered A. fragilis to the new species, including "Big Al" and "Big Al II". There's at least another paper or two in the works to be published; this first one only describes the skull differences, while the upcoming one(s) will address post-cranial differences and reevaluate the genus as a whole.

A Rhamphorhynchus tooth was found embedded in the body of a squid, providing the first hard evidence of pterosaurs eating cephalopods. This was actually published a couple days after this study came out describing the first known fossil trackway of a non-pterodactyloid pterosaur (like Rhamphorhynchus); pterosaur researcher Mark Witton describes why it's both weird and significant:


Another non-dinosaur example but just as interesting, a bonebed of Eremotherium laurillardi from Ecuador shows that these giant sloths may have been gregarious and in this particular case at least, congregating around mud wallows like hippos and other large mammalian species. It's an interesting happenstance follow-up to this recent blog post by the aforementioned Witton where he argues that at least some giant sloths might've looked a little different than we usually portray them due to thermoregulatory pressures. Not that there's ever really been much reason to imagine giant sloths as solitary, it's just one of those things that's never really been considered for some reason.

Insofar as paleomedia is concerned, there's been another entry in Ben G Thomas' Walking with Dinosaurs review series since I last mentioned it, going over the "Cruel Sea" episode. There's also been some development updates for Prehistoric Kingdom (basically a scientifically accurate prehistoric park builder game), including a pretty rad trio of new Smilodon models:

The other dinosaur game I'm following, Saurian, is working on their playable Triceratops patch. Most of it lately has been tying up loose ends on emergent social interactions between herd mates, as well as plant-related systems and restructuring the hatchling-stage life cycle since it turns out that baby Triceratops can't keep up with the adults when they're on the move.
Saurian DevLog #85 — Saurian
Saurian DevLog #86 — Saurian
Saurian DevLog #87 — Saurian
Saurian DevLog #88 — Saurian

And finally, here is a piece of paleoart I happened upon and really liked, featuring a bunch of dinosaurs for which there's decent evidence of their coloration:

 

[Iceman]

I wonder how many of the Carnivores had a toxic bite similar to the Komodo dragon?

The Megalania is a distant relative of the Komodo said to be larger and roamed Australia 40000 years ago is the largest toxic predator known as mentioned in this link describing recent additional discoveries concerning Komodo Dragon's Toxin:
More on Megalania:






The Current Komodo Dragon:

Some things I've noticed about this creature watching some nature videos on it just recently:
*There's some interesting videos I just found on Youtube concerning the current Komodo Dragon (way more deadly and quick than they look as seem kind of puppet like the way they saunter about but can run up about 12 mph doing a beeline over a decent distance). There's some that are so graphic I probably shouldn't post a link to it here but involves a deer essentially immobile due to the poison being slowly eaten alive. A pretty bad way to go.

*There's another youtube video ("Live Deer Ripped Apart By Komodo Dragons" it's called) of a crowd of them essentially all feasting on a live deer at once also too graphic to link to. You can literally hear the sounds of them crawling over each other to get to the deer and don't even bother chewing on the torn chunks but just inflate their necks and swallow it whole never being satiated seemingly as they can eat up to 80% of their body weight.

*There's another video of one biting a water bison then a bunch more casually coming out of the bush watching it for however long it takes as it slows down. Or, there's a separate video of a Komodo simply killing a smaller goat by catching it and bringing it down then a couple more appear out of nowhere and there's nothing left. Supposedly they can eat 80% of their body weight and horf down bone, cartillage, and everything down that long neck of their's sitting in belly almost the size of the animal itself. Even a small Komodo could probably horf down a human leg or arm quite easily.

*Their venom is so toxic there's now some disagreement on whether it's the 50 strains of bacteria from the sewer reservoir inside their gums between their teeth that wells up from when the jaw applies pressure around something grinding it with serrated teeth or another kind of venom as described in link above that simply causes the blood pressure to crash and leave one unable to fight back or move going into shock within a few hours for a human. The way they hunt can be seen under a Youtube video entitled "Powerful Komodo Dragons Observed Hunting In the Wild". This is also graphic in some parts but mainly focuses on the film crew spinning in circles with sticks in hand watching as more Komodo's keep showing up to a feast.

*They're quite a nightmare to deal with and can smell blood from 5 miles away. One would have to be turning in a circle constantly stick in hand ready to fend some off as they're very sneaky and quick especially if close by and so many popping out of no where honing in on whatever's in the scent area. In fact they've been known to dig up human graves by some accounts.

*They can be cannibalistic. So ravenous there's a nature photo I found online of a smaller one sticking it's head into the mouth of a bigger one to snatch it's food out. Komodo dragon sticks its head inside another one’s mouth to snatch its food | Daily Mail Online

*They're quite heavy as can be seen in videos of them fighting and hissing at one another. About 150-200 lbs typical but smaller ones can come out of nowhere and bigger ones said to be about 300 lbs too. Including tailspan 10 ft is typical. Komodo Dragon (Varanus komodoensis) | about animals and

As if these things weren’t vicious enough they get a toxic bite too!

 

[Melpardus]

So this has been published for well over a month now and I have no idea why it hasn't been reported on by much anybody yet -- though I suspect it might be simply because the researchers have a press release in the works, and I've started seeing a couple smaller outlets writing about it in the last few hours -- even though it's pretty significant. We've got non-avian dinosaur DNA, y'all. Granted, it's actually only about six or so base pairs, so nowhere near enough to sequence, let alone attempt to clone, and it's not clear whether what's been found is the DNA itself or just the chemical remnants of it. However, given its unique preservation and the fact that there's multiple layers of resolution -- chromosomes inside of fossilized nuclei within cells, some of which were undergoing mitosis, in an unossified cartilaginous skeletal matrix in a hatchling crested hadrosaur, Hypacrosaurus stebingeri -- it pretty strongly rules out other potential identifications like contaminating bacteria.

In other prehistoric news, there's some new specimens of Stupendemys geographicus, a massive riverine turtle from Miocene (13-5 mya) pan-Amazonia South America. And I do mean massive:

Spoiler

Aside from their size, the study also describes potential sexual dimorphism, with males being larger and having pointy structures on the front of their shells that are referred to as horns, which might've been used for intraspecific combat. Some of the shells also have bite marks from the giant 10 meter crocodilians that lived alongside them.

There's also this nice article from Mark Witton about another large Cenozoic oddity that you'll see from time to time but nobody really pays attention to, Arsinotherium: Mark Witton.com Blog: Horn function in Arsinoitherium OR... the ArSUMOitherium Hypothesis™ (You know, as excited as I am for Jon Favreau's upcoming BBC documentary Prehistoric Planet, which is supposed to be set in the Late Cretaceous -- almost certainly Hell Creek if they just focus on one location -- I'd actually really love a show focused on Cenozoic fauna outside of just the classic Ice Age stuff, although it'd be great to see those creatures done justice too.)

 

[:eek:]

'Warrior' dinosaur with nasty gouge mark on claw uncovered in New Mexico | Live Science

 

[Melpardus]

No major breaking news in the paleo world that I've been made aware of as of the time of this posting, but here's my periodic little round-up of all things prehistoric:

I guess the biggest thing in the last month or so was the flurry of online drama going on with this tiny fossil skull of some sort of new species of reptile found in amber from mid-Cretaceous Myanmar, called Oculudentavis khaungraae. Originally it was published (seemingly somewhat hastily) as a new species of hummingbird-sized toothed avian dinosaur, but within only days other researchers had reviewed it for themselves and it's since been much more heavily suggested that it's in fact some form of little lizard, a suggestion which lines up more with some of the features of the skull being very odd if it were truly from a bird. Outside of the science, the conditions under which the fossil and others like it that have been published in recent years (mostly in paleoentomology circles, though there was a whole feathered non-avian dinosaur tail found and described a couple years back) have come to light in mainstream news; it turns out that they're essentially blood diamonds, with people being forced into highly dangerous mines in the middle of conflict zones to recover various semi-precious rocks to be sold by militias in Myanmar to help fund a brutal conflict. Given these conditions and the fact that the Myanmar amber fossils are purchased in markets, it sparked a debate in paleontology circles about whether it's ethical to study and publish on the specimens that have already been collected. (I'm perfectly fine with them being boycotted altogether at this point, though personally I'm of the mind that it's okay to publish on them so long as every reference to them in some way includes an acknowledgement of their circumstances of their acquisition and any profit made from such work goes to organizations that can potentially help alleviate if not end the situation there.)

There was an actual new ancient bird published only a couple days later, Asteriornis maastrichtensis from Late Cretaceous Belgium, notable due to its discovered phylogenetic placement as being close to the last common ancestor of all modern fowl (galloanserans).

There was a new species of toothy Cretaceous pterosaur published that preserves patches of skin in a way that suggests that it had a bald head. This would be the first time such a case has been seen in any pterosaur, which usually are depicted with full coverings of feathers (or "pycnofibers" if you want to be a stickler and not consider them homologous to dinosaur feathers) from head to tail based on a number of fossils preserving their soft tissues.

A fairly complete new 'prosauropod' dinosaur was described from Late Triassic Lesotho (from a bone bed, no less) and was named Kholumolumo ellenbergerorum, after a dragon-type monster in Sotho (think the Border Tribe from Black Panther) legend of the same name. I personally wouldn't have named it that considering that 'prosauropods' were herbivorous, but I don't call the shots.

There's online rumblings of the publication of a new study on the genus of giant Late Cretaceous crocodilian Deinosuchus that basically is going to reduce its species count to one (D. hatcheri) while shifting the other two species (rugosus (which is itself being renamed to schwimmeri) and riograndensis) are getting assigned to a new genus name that has yet to be announced. The paper might also finally publish on the skull morphology of riograndensis, which is weird to say the least:


As far as more general reading and media is concerned, Mark Witton has a good write-up on the true nature of dromaeosaurs (raptors) that is just part one of a two-part series that addresses a bunch of popular misconceptions of raptor biology and ecology (and is more in-depth than just "this is what Jurassic Park got wrong). Definitely recommended reading and keeping the eye open for the follow-up. While we're on dromaeosaurs, there's a new Your Dinosaurs Are Wrong video out on Velociraptor; I haven't watched it yet but I'm sure it's good. There's also this nice little piece that's definitely worth a watch:


There's also this new bit in the works, and finally, this really good-looking new documentary mini-series on prehistoric mammals with CGI models that look good enough that I saw this gif out of context and was really struggling for a second to try and figure out exactly what I was looking at. (I don't know if there's an English version but it should have subtitles at least.) Not much on the video game front, but there's this little clip of some Triceratops in Saurian dealing with a nosy T. rex:

 

[Melpardus]

Apologies for the double post (even if they are over a week apart) but there's some big news that just came out a couple hours ago:

Spinosaurus just keeps getting weirder and I love it. (Paper here if you want to read it; the first link is to a video that sums up most of the important points.)

I mean, just look at this thing.

Spoiler

As Andrea Cau explains, this is pretty much the nail in the coffin for various objections that were raised back in 2014 against this new amphibious interpretation of Spinosaurus. Not that there haven't been mounting bits of evidence since 2014 and even before the short-legged study was published, but a whole tail with this weird morphology is literally the biggest piece of evidence so far showing that these guys were very much not the creatures shown in Jurassic Park III.

The paper and blogposts by other researchers in the know about the discovery hint at there also being arm material from the site that might add yet another level of weirdness in the next couple years once they're fully excavated and studied. (The skeletal and other images are already kind of teasing this anyway given how they're drawn and obscured.) I'm placing my bet now that the arms were actually reduced and the hands were just webbed flipper-type structures like seals and seal lions.

This discovery actually comes about a week after this paper was published summing up and describing the environment and faunal assemblage of the animals of the Kem Kem beds in Morocco that this Spinosaurus is from, in case you want more ecological context for this weird animal.

While I'm here though, here's a few other things that have come up in the paleo world since I last posted:

Two other studies published today, the first one describing a new species of ceratopsian (Stellasaurus ancellae) and detailing a proposed anagenetic lineage (meaning species A evolves into species B which then evolves into C, rather than A splitting into B and C) between Styracosaurus, Stellasaurus, and Einiosaurus. The second study describes a new Mesozoic mammal from Late Cretaceous Madagascar. It's large for mammals from that era, but other than that and some apparently significant taxonomy stuff, I don't know too much about it to elaborate.

A couple days ago saw the publication of a new species of ornithomimid from Mexico (Paraxenisaurus normalensis) that might be related to the weird Mongolian Deinocheirus.

Mark Witton has another post out on giant sea reptiles, specifically pliosaurs and ichthyosaurs that is well worth a read if you want to have your mind blown (and also kill any expectations you might have about Liopleurodon after a certain pop culture appearance): Mark Witton.com Blog: In pursuit of giant pliosaurids and whale-sized ichthyosaurs

Finally, some lovely old paleoart by some folks who really were ahead of their time in many respects:


I think the most interesting take-home point is that they provide a decent argument against the refrain "Modern depictions looks so much different from old ones and so all of the stuff we have now will be completely invalid in a couple decades", because the reality is that no, if you study anatomy and have good enough material to work with, there's some stuff that you're just going to get right. Accuracy isn't as much of a moving target as people sometimes try to make it seem. There is still some stuff in those images that are outdated or just wrong at this point (like the legs on the large carnosaur and the way the fingers stick out of the wing in the colored Archaeopteryx picture) but they're pretty modern looking in many other respects.

 

[:eek:]

T. rex was a deadly 'power-walker' | Live Science

 

[Melpardus]

This actually isn't the first study to come to this conclusion, but it's always nice to have more data points. Tyrannosaurs were a group that started out as small fast-running predators living in the shadow of other theropod groups like allosauroids, so the retention of those traits throughout their evolutionary lineage makes sense. I really do appreciate the emphasis on shifting the focus of predatory locomotion away from top speed and more towards foraging efficiency; it just makes a lot more practical sense in many respects. (That said, though, the study also looked at a variety of other theropods and calculated similar metrics for them, producing some new speed estimates.)

Other major paleo and evolutionary biology news from the last few weeks:

The discovery that Deinonychus juveniles had a different diet from the adults provides the strongest piece of evidence yet that suggests against raptors having a wolf-like pack structure. (In animals that usually live and hunt in groups, packs are family structures primarily made up of parents and their successive generations of offspring.)

Based on a study done on gharials, trying to determine the sex of an animal based on skeletal anatomy is difficult if not impossible, even if you're dealing with a species that has sexually dimorphic skeletal traits. What this means for dinosaurs should be fairly self-evident. There have been individual dinosaurs that have been sexed, but those results are based on bone histology, specifically looking for the presence or absence of a type of bone tissue called medullary bone that female birds produce when they are gravid (pregnant with eggs).

This should speak for itself: https://royalsocietypublishing.org/doi/10.1098/rsos.192260

A wide-scale genetic study on the evolutionary history of lions, which have been around for about as long as anatomically modern humans (~500,000 years) and branched into a number of different subspecies, including the extinct cave lions of Europe and North American lions. Very in-depth and very cool if you're interested in that sort of thing.

The publication of a new fossil site from Pleistocene Australia reveals a menagerie of megafaunal species both new and old (to science) -- including a new giant kangaroo that towers over the current record holder -- and discusses what if any effect the introduction of humans might have had on the extinction of these animals in addition to climate change.

Speaking of humans, two studies published almost concurrently show that modern Homo sapiens moved into Europe earlier than previously thought and had both genetic and cultural exchange with local Neanderthal populations for a couple thousand years. The 2010s have painted a very interesting picture of the nature of what humanity in Europe would've looked like; I'm hoping that Terry Notary and the Russo brothers take all of this new info into account once they get started on that Neanderthal film that was announced a couple years ago.

Not much in my paleomedia round-up this time; everyone's pretty much just been drawing Spinosaurus for the last few weeks (though as my favorite non-avian dinosaur, I can't be mad at that) so Mark Witton has a new article out regarding the relevant stuff people should know based on what is currently known and things that still need to be figured out.

There's a video out on Jack Horner's "chickenosaur" project, going into the scientific and ethical issue involved from the perspective of geneticist who was actually tangentially involved in the project itself:


And finally a self-plug for my first YouTube video that'll hopefully be that start of an ongoing series on Triassic fauna, because the Triassic Period is weird and sadly overlooked and I wish to do something about that even with my janky sound editing skills.

 

[Schlosser85]

Recently Discovered Dinosaur ‘Mummy’ Is So Well-Preserved It Even Has The Skin And Guts Intact

 

[:eek:]

Ancient crocodile walked on two legs | Live Science

 

[Melpardus]

Recently Discovered Dinosaur ‘Mummy’ Is So Well-Preserved It Even Has The Skin And Guts Intact

Not only that, but Borealopelta also preserved melanosomes (color pigments) that show that it was reddish-brown with a countershaded pattern (dark on top, light on the underbelly). In addition, another study showed the extension of the keratinous covering on the osteoderms (armour) in this guy, and its shoulder spikes were pretty impressive, so overall by way one single fossil we can pretty confidently say that this is one of the best understood extinct dinosaurs insofar as life appearance goes. Jacob Baardse's take is one of my favorites:

Quick roundup of some recent paleo-news, as per usual:

• Dilophosaurus got a bit of a touch-up after a massive paper thoroughly reanalyzing all five known specimens which prior to this hadn't really been properly looked at since they were first discovered. Main takeaway is that most recons you've seen of this animal are based on immature subadult specimens, but the adults were considerably bulkier in overall build (though still on the lithe side for mid-large theropods) with more robust skulls and crests even taller than previously thought. Paleoartist Brian Engh is working on a life-sized model of the animal now:
• Another big reanalysis paper, this time looking at the relationships within ornithopods (the group that more or less includes ceratopsians, pachycephalosaurs, and hadrosaurs). The study basically overturned the last 20+ years of understanding, with the biggest shakeup being the group called heterodontosaurs are actually paraphyletic (not a true/natural familial grouping) while still being ancestral to pachycephalosaurs. Also Chilesaurus is an ornithischian now as opposed to being some weird theropod as it was initially touted as when it was first discovered in the mid-2010s.
• Two big papers regarding prehistoric eggs that came out on the same day in the same journal. The first described the evolution of hard eggshells and found that dinosaurs likely started out with soft-shelled eggs, and certain lineages (some theropods, sauropods, and hadrosaurs) later independently developed hardened shells more similar to birds than crocodilians and lizards. The paper went on to postulate that the lack of preserved eggshells for certain groups (like ceratopsians and thyreophorans (stegosaurs and ankylosaurs)) despite their relative fossil abundance might owe to them having soft shells that were less likely to be preserved.
• This becomes relevant for the second paper, which described a giant egg from Late Cretaceous Antarctica that appears to have been soft-shelled based on the mineral composition of the fossil. The egg (lacking an embryo) was preserved in a shallow coastal marine environment, a factor which (among others) led the researchers to controversially attribute it to a mosasaur. This flies in the face of known mosasaur biology considering that these animals have been shown to give birth to live young, and so wouldn't make sense unless there was either variation in reproductive strategies across different mosasaur species or mosasaurs had an ovoviviparous strategy (meaning eggs were hatched inside the body of the mother and then the babies were born) like some modern snakes. Given this, a lot of people have been arguing that the egg is from a soft-shell-laying large dinosaur (chiefly an ankylosaur, which are the only known groups from the right time and place) that simply got washed out to sea. It wouldn't be the first time such a thing has happened to ankylosaur fossils. Personally I prefer the mosasaur idea, but it's very much up in the air right now and the ankylosaur suggestion is more parsimonious.
• Meet Kongonaphon kely, a tiny (10 cm tall!) reptile from Triassic Madagascar that is likely representative of the common ancestor(s) between dinosaurs and pterosaurs.
• Also meet Trierarchuncus prairiensis, a small alvarezsaur from the Hell Creek Formation of Western North America (the stomping grounds of T. rex and Triceratops and other Late Cretaceous favorites). It's name (which roughly means "Captain Hook of the prairie") refers to the giant claw on its single finger that is characteristic to its group.
• Also, a mammal scavenged a sauropod bone and we have moulting patterns for Microraptor now that show that flight was indeed important to this animal's lifestyle.

Paleo-media round-up:

• A fun article covering some big prehistoric octopus relatives: Reconstructing fossil cephalopods: Enchoteuthis (“Tusoteuthis” )
• A not-as-fun article touching on racism in paleoart: Mark Witton.com Blog: Racism in palaeoart and #BlackLivesMatter
• Two nearly concurrent videos discussing the topic of lips in Tyrannosaurus and Spinosaurus.
• A video and Twitter thread clowning and bemoaning the Discovery Channel's newest reality show, Dino Hunters.
• And finally, an online acquaintance of mine showing some love to the overlooked prehistoric fauna of pre-dinosaurian times:
  

(Also I'm angling to do something for Shark Week on my own channel. Will post when it's ready.)

 

[Boom]

Recently Discovered Dinosaur ‘Mummy’ Is So Well-Preserved It Even Has The Skin And Guts Intact

This stuff is so ****ing cool. Imagine being the person to find this.

One of my biggest pipe dreams is living to see the discovery of a mummified T-Rex.

 

[signalman]

I have been watching DINO HUNTERS on Discovery Channel.
Been somewhat interesting and they have dug out some cool fossils.

New Series 'Dino Hunters' Unveils Shocking Fossil Find

 

[Melpardus]

The guys in the show aren't necessarily bad guys, but the show itself is pretty garbage from what I've seen. The video I posted on this topic goes over some of the main points regarding the legal, scientific, and ethical issues regarding the commercial fossil trade that the show ultimately promotes or makes worse, and the thread I linked is pretty self evident for how low quality the program is in its presentation. ("Nanotyrannus" has already been an invalid idea for decades, but these "experts" can't even use the right name and the show presents it as a "Nanotyrannosaur", which was never a thing. Plus the CG models are absolutely the worst I've ever seen, and I should note that it's been found that they were bought from a website that carries malware.)

Most people that I know in the paleontology sphere who are watching the show are mostly hate-watching it and/or looking to see what specifically they're finding, with the full expectation that a lot of those fossils will never get to be properly studied and so are effectively lost to science.

 

[signalman]

New insights into the Tanystropheus.

Long Neck Helped Reptile Hunt Underwater - HeritageDaily - Archaeology News

 

[Melpardus]

Paleontology news is pretty much the only good thing 2020 has brought so far. Someone sent me this yesterday and it's really cool, though I haven't had the time to read the full paper yet. Having two contemporaneous species within the same genus with evidence of niche partitioning isn't very common in the fossil record, so that's pretty cool in itself. Seemingly finally starting to figure out what the heck these animals were actually doing with their lives is even cooler.

 

[:eek:]

Cretaceous 'terror crocodile' crushed dinosaurs with banana-size teeth | Live Science

 

[Melpardus]

Deinosuchus isn't new and the new study about it has nothing to do with its diet, it's just that this got published recently.

There's online rumblings of the publication of a new study on the genus of giant Late Cretaceous crocodilian Deinosuchus that basically is going to reduce its species count to one (D. hatcheri) while shifting the other two species (rugosus (which is itself being renamed to schwimmeri) and riograndensis) are getting assigned to a new genus name that has yet to be announced. The paper might also finally publish on the skull morphology of riograndensis, which is weird to say the least:

I hate pop sci articles, I really do. (I should write for some of these websites.)

It's been long enough so I might as well do the round-up. News-wise the two biggest stories of the last month have already been posted here (the Deinosuchus reclassification paper and the Tanystropheus stuff). There hasn't been a ton more that I'm aware of, but there was a study on the extinction of wooly rhinos finding that the main factor was indeed likely climate change rather than human predation. A different study came out earlier this week describing the fossil of a large ichthyosaur (the dolphin-looking marine reptiles) that had killed and eaten another large marine reptile shortly before its death, providing the clearest evidence that we've been underestimating the predatory capabilities of ichthyosaurs for a long time. And finally, the saga of the ever-controversial Myanmar amber skull Oculudentavis, continues. First the authors retracted the original paper on account of learning about the then-soon-to-be-published study on a second, more complete specimen of the same animal (not from an amber stone) that confirmed that it was a lizard, not a tiny bird. The authors of the original retracted paper also joined in with a bunch of other researchers in this letter rebutting the Society of Vertebrate Paleontology's decision to place a moratorium on research conducted on the Myanmar amber fossils on account of their bloody origins. Personally I don't find the rebuttal to be that good of an argument.

Media time... (Putting them in spoilers just to save scrolling.)

There's been some really good paleoart coming out in the last few weeks and I've been looking forward to sharing it here for folks a bit outside of the circles.

Spoiler

My favorite Dilophosaurus piece so far since the new study on its adult form with bigger crests:

A Deinosuchus riograndensis made in time for the new study's release:

A really cool, if perhaps slightly improbable, animation of a pair of T. rex not being movie monsters:

Some Permian pre-mammals:

A reason for why I wish a big studio would be more willing to portray dinosaurs beyond the Jurassic Park imagery:

The Field Museum's new "Sue" the T. rex model is officially done. It's a traveling exhibit, so I really hope it comes to the AMNH. Way better than the one they had there for the past year or so, which I made a short review of on my channel.

And finally, this.

Beautiful.

Also there's some Shark Week stuff from last week by a bunch of natural history-focused YouTube channels in order to supplement if not counteract the programming on Discovery Channel proper. I wasn't able to finish my project in time to contribute, but I definitely suggest giving them a watch. There's some stuff about megalodons and other prehistoric sharks (and some technically not-sharks but close enough in appearance to be counted) in there.