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Quetzalcoatlus: the evil, pin-headed, toothy nightmare monster that wants to eat your soul

The views expressed are those of the author and are not necessarily those of Scientific American.


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Did the giant pterosaur Quetzalcoatlus really look like this? That is, was it from Hell, and did it actually absorb the souls of baby dinosaurs? Let us hope not...

Regular readers of Tet Zoo will be familiar with two topics I’ve covered on and off over the years: azhdarchid pterosaurs, and palaeoart memes. Azhdarchids were mostly large to gigantic, long-skulled Cretaceous pterosaurs, noted for their enormous wingspans (up to 10 m or so in the case of Quetzalcoatlus from the USA and Hatzegopteryx from Romania), elongate necks, and long, stork-like jaws. Tradition would have it that these animals were vulture-like scavengers or water-trawling piscivores, but consideration of everything we know about their wing form, body shape, overall ecomorphology, trace fossil record, palaeoenvironment and so on shows that they were strongly terrestrial animals that most likely foraged quadrupedally in continental environments, reaching down to grab animal and plant prey in a manner analogous to that practised today by marabou storks and ground hornbills (Witton & Naish 2008). Mark Witton and I dub this the ‘terrestrial stalking hypothesis’ and we have more to say on it in a paper currently in review at a major open-access journal.

Demonic Quetzalcoatlus illustrated by Guy Michel in 1979. Read on for details and origins.

Palaeoart memes are those traditions we so frequently see in the history of palaeontological art whereby artists copy the behavioural hypotheses, body shapes, postures and even colour schemes of given animals again and again and again, not because they’re well supported or based on evidence of any sort, but simply because that’s what’s been depicted beforehand. Examples can be seen everywhere, with my favourites including Freaky Giraffoid Barosaurus, black-and-white Phorusrhacos, Scolosaurus the mega-louse, Big Buzzard Teratorn, and…. Demonic Quetzalcoatlus.

By now, it’s reasonably well known to interested people what azhdarchid pterosaurs looked like when alive. The answer: sort of like a cross between a giraffe and a stork, though with all of this being over-ridden by uniquely pterosaurian weirdness; membranous wings supported by giant fingers, a large cranial crest, plantigrade feet, and so on.

Richard Orr's brilliant depiction of a Demonic Quetzalcoatlus group squabbling over a dinosaur carcass. In the full image, a Tyrannosaurus is approaching from the far distance.

I first got to know Quetzalcoatlus as a very, very different beast, however. Little known today is that Quetzalcoatlus was depicted as a most peculiar creature in a few books from the 1970s and 80s. As you can see from the images reproduced here (the black-and-white image above is by Guy Michel and appeared in John Gilbert’s 1979 book Dinosaurs Discovered), it was depicted as a short-headed pterosaur with a bony lump on the back of its head, a very flexible neck, and pointed, toothy jaws. Imagined like this, it really looks like some sort of horrific demon. Richard Orr’s painting – shown at the top of this article and adjacent – always makes me think of one of Hieronymus Bosch’s scenes of Hell. Truly, it’s a horrific, terrifying scene (and I don’t mean that as a slight to Orr’s good artwork). Where on earth did this view of Quetzalcoatlus – I call it the Demonic Quetzalcoatlus – come from?

Giovanni Caselli's 1975 Demon Quetz, the image that started the meme.

Orr’s painting comes from a book written by the unique Dougal Dixon* (Prehistoric Reptiles), and originally published in 1984 (I only have a 1993 edition). It’s obvious from many of the scenes included in the book that Orr had been heavily inspired by Giovanni Caselli’s reconstructions from L. B. Halstead’s The Evolution and Ecology of the Dinosaurs, first published in 1975. Sure enough, if we look at Halstead’s book, we see another version of the same creature. Caselli didn’t show the animals in as much detail as Orr or Michel did, but we again see a comparatively short skull and a blunt, knob-like crest at the back of the head. The animals are also shown as being red, just like Orr’s creature. As mentioned above, this is a classic feature of the palaeoart meme: the creatures are given the same livery, just because. Anyway, Caselli’s version came first – but where did it come from?

* More on him soon! I just gave a talk partially devoted to Dixoniana at the 2013 Weird Weekend conference.

The late L. B. Halstead's The Evolution & Ecology of the Dinosaurs, one of the most influential of dinosaur books when it comes to palaeoart memes. There are two editions, famously differing in how they treat the 'flippers' of Compsognathus.

I asked Giovanni Caselli himself back in 2010. When the illustrations for The Evolution and Ecology of the Dinosaurs were being produced, Quetzalcoatlus had only just been announced, and hadn’t even been named (evidently, we’re talking about some time between 1972 and 1975). There was thus no idea what it might look like: all that was known was that it was a giant pterosaur that lived inland. Giovanni’s painting was, he told me, a complete exercise in speculation…

“I took some time to find out about this issue. Naturally, since Halstead has been long dead, I had to dig through my archive but only to find that, being the discovery very recent and not yet documented at the time, Halstead told me just to do a small illustration of a huge pterosaur, and I did just that. Any similarity or difference as compared with present-day renditions is purely accidental (as they say in other fields of entertainment).”

How ironic, then, that his conjectural creation became a palaeoart meme that persisted until the 1990s at least (the Richard Orr version was appearing in 1993 editions of Dougal Dixon’s Prehistoric Reptiles).

Bob Hersey's purple Demonic Quetzalcoatlus, c. 1980. A thing of pure terror.

Paul Glynn reminded me that there’s another version out there: Bob Hersey’s purple Quetzalcoatlus from David Norman’s 1980 Spotter’s Guide to Dinosaurs & Other Prehistoric Animals (Norman 1980). I show it here. Hersey’s purple version is very obviously based on Caselli’s painting, and I’m 99% certain that the other Demonic Quetzalcoatlus images out there are based on his painting too. Another appears in Usborne’s 1977 Children’s Encyclopedia of Prehistoric Life, written by Anne McCord but with Halstead providing expert advice (McCord 1977). This time round, the artist was at least original enough to make the animal brown, not reddish.

A Demonic Quetzalcoatlus skeleton!

It gets better: I give you an actual skeleton of a real Demonic Quetzalcoatlus! Well, a published drawing of one, anyway. Just like the animals depicted in those various sources discussed above, this skeleton shows all the characteristic features of its meme: it has a long neck (made up of many small vertebrae, and hence presumably quite flexible*), a relatively short skull, a lump-like, posteriorly projecting crest at the back of its head and small, pointed teeth. Wow. I bet you had no idea that such a skeleton had ever been found.

It hadn’t, of course. The artist (Chris Forsey) must have been asked to “do a Quetzalcoatlus skeleton”, and must have invented what you see here. I presume that Forsey looked at the Demonic Quetzalcoatlus renditions produced by Gilbert, Orr and those other artists, the hypothetical skeleton you see here being the result. I don’t know this, of course: as you’ll no doubt have noticed, this palaeoart meme stuff involves an awful lot of guesswork, some or all of which might be erroneous. But the similarity between this alleged Quetzalcoatlus and the horrendous reddish demons we looked at above is striking, and unlikely to be coincidental. Forsey’s version was first published in 1986 – the book is called The Day of the Dinosaurs (Stidworthy 1986) – and republished in 1999.

* A marked contrast to the real azhdarchid neck, with its lower number of long, cylindrical vertebrae and reduced flexibility (Witton & Naish 2008).

Even the most complete of the real Quetzalcoatlus specimens is nowhere near complete as the skeleton shown in Forsey’s sketch. But I wondered if the look and pose of Forsey’s Demonic Quetzalcoatlus skeleton was based on a real specimen, perhaps of one of the substantially smaller, Solnhofen pterosaurs. Tipped off by Pete Buchholz (him again), I realised that it’s copied directly from a Pterodactylus skeleton that features on p. 10 of Peter Wellnhofer’s Illustrated Encyclopedia of Pterosaurs (Wellnhofer 1991). And the funny thing is – that skeleton is the very first skeleton illustrated in the book. The broken wing finger makes this 100% certain.

More accurate renditions of Quetzalcoatlus - this time with a long, toothless rostrum - were appearing in the literature by the end of the 1970s. This sketch appeared in a 1977 article by Wann Langston.

By 1977, Wann Langston was illustrating Quetzalcoatlus as the long-snouted pterosaur that it really was, and copious artwork depicting Quetzalcoatlus more accurately appeared throughout the 80s, 90s and into modern times (for especially up-to-date azhdarchids, I point of course to Mark Witton’s excellent 2013 volume Pterosaurs). One of the great frustrations of azhdarchid research is that good anatomical information on Quetzalcoatlus has never been published: there’s a paper on the cranial remains of Quetzalcoatlus sp., one of the smaller of the three azhdarchids (Vremir et al. 2013) known from the Texan Javelina Formation (Kellner & Langston 1996), but good data on Q. northropi, the giant Javelina azhdarchid, is very thin on the ground; this despite the fact that the animal was first reported during the 1970s (Lawson 1975). Wann Langston – the palaeontologist who was supposed to be describing Q. northropi – died earlier this year, and right now it’s unsure what, if anything, is going to happen. Science does march on, but sometimes the march is more of a slow crawl…

UPDATE: coincidentally, an excellent article about changing views on azhdarchid pterosaurs has just been published on Mark Witton’s blog. Check out 9 things you may not know about giant azhdarchid pterosaurs.
UPDATE 2: those wonderful people at io9 liked the subject matter enough to cover it. Check out This is one of the scariest (and wrongest) pterosaur pictures ever.

For previous Tet Zoo articles on azhdarchids (and other azhdarchoid pterosaurs), see…

Refs – -

Dixon, D. 1993. Prehistoric Reptiles. Evans Brothers Limited, London.

Gilbert, J. 1979. Dinosaurs Discovered. Hamlyn, London.

Halstead, L. B. 1975. The Evolution and Ecology of the Dinosaurs. Peter Lowe, London.

Kellner, A. W. A. & Langston, W. 1996. Cranial remains of Quetzalcoatlus (Pterosauria, Azhdarchidae) from Late Cretaceous sediments of Big Bend National Park, Texas. Journal of Vertebrate Paleontology 16, 222-231.

Lawson, D. A. 1975. Pterosaur from the latest Cretaceous of west Texas: discovery of the largest flying creature. Science 187, 947-948.

McCord, A. 1977. Children’s Encyclopedia of Prehistoric Life. Usborne, London.

Norman, D. B. 1980. Spotter’s Guide to Dinosaurs & Other Prehistoric Animals. Usborne, London.

Stidworthy, J. 1986. The Day of the Dinosaurs. Macdonald & Co, London.

Vremir, M., Kellner, A. W. A., Naish. D. & Dyke, G. J. 2013. A new azhdarchid pterosaur from the Late Cretaceous of the Transylvanian Basin, Romania: implications for azhdarchid diversity and distribution. PLoS ONE 8(1): e54268. doi:10.1371/journal.pone.0054268

Wellnhofer, P. 1991. The Illustrated Encyclopedia of Pterosaurs. Salamander Books Ltd, London.

Witton, M. P. & Naish, D. 2008. A reappraisal of azhdarchid pterosaur functional morphology and paleoecology. PLoS ONE 3 (5): e2271. doi:10.1371/journal.pone.0002271

Darren Naish About the Author: Darren Naish is a science writer, technical editor and palaeozoologist (affiliated with the University of Southampton, UK). He mostly works on Cretaceous dinosaurs and pterosaurs but has an avid interest in all things tetrapod. His publications can be downloaded at darrennaish.wordpress.com. He has been blogging at Tetrapod Zoology since 2006. Check out the Tet Zoo podcast at tetzoo.com!

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The views expressed are those of the author and are not necessarily those of Scientific American.





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  1. 1. Richard Freeman 11:22 am 08/20/2013

    Clearly this was the same creature resurrected by Mexican cultists in New York in the early 1980s. It apparently favoured roosting atop sky scrapers and snatching is prey from penthouse swimming pools.

    Link to this
  2. 2. llewelly 11:27 am 08/20/2013

    Original:

    730 words, 4792 characters.

    Revised:

    1584 words, 9891 characters.

    (Approximate. I’m too lazy to pick out the image urls that got counted in the original but not in the revised.)

    About 2.17 times as much content.

    Furthermore, the answer to the question posed at the end!

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  3. 3. naishd 11:30 am 08/20/2013

    I do remember thinking that the creature in Q – The Winged Serpent is indeed based on ‘Demonic Quetzalcoatlus‘. Can’t remember if I got anywhere in my research on this. The film is from 1982 so it’s conceivable, but the anatomical similarities are scant.

    Darren

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  4. 4. MMartyniuk 11:55 am 08/20/2013

    I can’t help but think it’s completely scandalous that Quetzalcoatlus has gone essentially undescribed for *forty years*! I’ve know Langston kept the specimens to himself and wouldn’t let anyone else work on them, but come on, it’s a fragmentary specimen that shouldn’t be THAT hard to describe…

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  5. 5. JoseD 12:14 pm 08/20/2013

    @Naishd: “Wann Langston – the palaeontologist who was supposed to be describing Q. northropi – died earlier this year, and right now it’s unsure what, if anything, is going to happen. Science does march on, but sometimes the march is more of a slow crawl…”

    Maybe you &/or Witton could continue where he left off. Given how much you 2 have already done to change our ideas about azhdarchids, it would only make sense IMO.

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  6. 6. Heteromeles 12:19 pm 08/20/2013

    I should point out that L. Sprague de Camp published a collection of short fantasy stories titled The Purple Pterodactyls in 1980. The pterodactyls in question were prizes at a carnival game, not real critters. What I’d like to know is whether there were purple pterodactyls before or after that book came out. It would be humorous if Bob Hersey’s illustration was inspired by de Camp’s title.

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  7. 7. SteveO 3:10 pm 08/20/2013

    Fascinating article – as one who was inspired by dinosaur art now known to be, technically speaking, boooogus, these are fun detective stories. Though too, I went to school at the Colorado School of Mines, and they had some of Arthur Lakes’ dinosaur paintings that really were more accurate than some of the stuff from the 60′s and 70′s.

    One quibble, “Mark Witton and I” not “Mark Witton and me.”

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  8. 8. SteveinOG 3:16 pm 08/20/2013

    In an age when all large land animals were egg-layers, and nests, even fields of nests, must have been abundant, it seems much more likely that the azhdarchids were nest raiders. The energy budget to land and take off seems too great for these huge beasts to alight on the open landscape on the chance of finding and snatching small live prey. Landing on a nest would provide an almost certain guarantee of a meal. It would have been much easier to spot an unattended nest site from the air, than to spot small animals hiding in the brush.

    The inflexible neck and sword-like bill don’t seem likely to have the agility necessary to capture small prey that would flee long before the towering animal got close (a stronger, more supple neck and shorter, hooked beak would probably have evolved instead). The neck and bill seem much better suited for hammering straight down. Most likely they used the bill to penetrate detritis piled on nests and jab into the egg shells.

    It would be difficult to prove this, but it’s more likely than the foraging scenario in IMHO.

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  9. 9. naishd 5:44 pm 08/20/2013

    Thanks for comments. Some responses…

    JoseD (comment # 5) says “Maybe you &/or Witton could continue where he left off.” Nice idea (and, thanks) but things are rarely that simple with a specimen considered so important. It will be described by someone based in Texas and/or involved with Langston’s work.

    SteveOG (comment # 8): I can’t see that your proposal makes a lot of sense since, even if the bill and neck anatomy makes sense for jabbing into an egg, what then? Does the bill stay stuck on the azhdarchid’s jaw tips, does it somehow suck up the egg contents? Furthermore, while you might be right about vast quantities of eggs being available on occasion, eggs are typically an ephemeral resource and animals have to be hyper-specialised to rely on them. No, the idea of azhdarchids foraging on foot and reaching down to grab small animals and other edible prey is far more likely: it has extant analogues (the aforementioned storks and hornbills), it fits with the fact that azhdarchids are widespread and known from diverse habitats and from all latitudes, and it is consistent with their anatomical details (long, pointed jaws and so on). Facultative egg-eating is definitely on the cards, but not specialisation for this habit.

    Darren

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  10. 10. Heteromeles 5:46 pm 08/20/2013

    @Steve: I’d buy that, except that it puts a lot of strain on the atlas vertebra of the beast playing pickax with a long, stiff neck.

    Having an oversized forceps isn’t necessarily a bad thing for a predator (ask anyone who collects scorpions). For one, a long, straight bill might work in certain kinds of vegetation, like the fern and lycopod savannas posited for the area. Just as herons can kill rabbits, it’s possible for stork shaped pterosaurs to go after small prey.

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  11. 11. Andreas Johansson 1:11 am 08/21/2013

    To my eyes, the “demonic Quetz” doesn’t look very demonic. As a kid, I thought it looked sort of disappointingly nonflamboyant compared to Pteranodon.

    The Halstead book was a staple of my childhood dino phase. Now I’m curious – my father’s copy (a Swedish translation) showed two versions of Compsognathus, one with more-or-less normal theropod hands, one with flippers. What’s the other treatment?

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  12. 12. Dartian 1:25 am 08/21/2013

    SteveinOG:
    an unattended nest site

    Extant birds and crocodylians typically guard their nests. Why would Mesozoic archosaurs have been any different in this regard? There is no reason to assume that dinosaur eggs would have been easy pickings for pterosaurs.

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  13. 13. Chabier G. 5:37 am 08/21/2013

    I find skull anatomy of Quetzalcoatlus really bizarre. I can’t see where the jaw muscles attached, having so short postorbital skulls. I wonder if the skull crest might be an extra surface to support the adductor mandibulae complex, necessary to close such a huge jaw with some effectiveness, something like the extra post parietal bone of modern cormorants. The enormous antorbital fenestra is another odd feature, and, once again, I think it might shelter huge pterygoideus musculature, another way to close jaws, as in modern storks.
    Of course, I haven’t got any knowledge about detailed anatomy of these pterosaur skulls (are there any surfaces identifiable as muscle insertion zones?), but they had to possess powerful muscles somewhere, to deal with such a massive bill.

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  14. 14. naishd 6:29 am 08/21/2013

    Andreas (comment 11): the first edition of Halstead’s book endorses the idea of a flippered Compsognathus corralestris; the second edition has a different section of text, saying that the ‘flipper’ turned out to be a misidentified chunk of wood. The art is the same in both.

    Darren

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  15. 15. naishd 6:39 am 08/21/2013

    Chabier G (comment # 13): you’re right that there are not large muscle attachment sites at the back of the azhdarchid skull, so no reason to think that they had especially strong or large jaw muscles. Muscle attachment sites suggest that the adductor and depressor mandibulae temporalis muscles would have anchored to the postorbital region (as is typical) while the pterygoideus would attach to the posterior part of the palatal region. Several papers illustrate the possible pattern of musculature – let me know if you need the references.

    Darren

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  16. 16. David Marjanović 10:32 am 08/21/2013

    The animals are also shown as being red, just like Orr’s creature

    …which is actually brown…? Light brown, on the orange side of the brown spectrum, admittedly, but still not red.

    I can’t help but think it’s completely scandalous that Quetzalcoatlus has gone essentially undescribed for *forty years*!

    Completely scandalous, but not actually unusual. Very little was published about Doleserpeton, a temnospondyl very important for hypotheses on the origin of Lissamphibia, between the extended abstract in Science (1969) and the full description in the Journal of Vertebrate Paleontology (2010). That’s a case where the original author had the good sense to get a grad student before dying.

    One quibble, “Mark Witton and I” not “Mark Witton and me.”

    Possibly under French influence, English has long used the oblique forms of personal pronouns for emphasis.

    the idea of a flippered Compsognathus corralestris

    C. corallestris.

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  17. 17. naishd 10:40 am 08/21/2013

    Oh yeah, brown. My colour vision isn’t very good.

    As for “x and me” vs “x and I”, I’ve been corrected, counter-corrected and corrected again so many times that I’m beyond caring. I grew up being told that it should be “x and I” but was corrected by Grammar Nazis several times both on Tet Zoo and while editing books and such.

    As for corallestris… d’oh! I should have checked.

    Darren

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  18. 18. Andreas Johansson 12:13 pm 08/21/2013

    Darren (#14): The Sw. translation would’ve been based on the 1st edition, then.

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  19. 19. Richard Freeman 12:26 pm 08/21/2013

    I the bad winter of 1963 there were records of herons killing and eating cats. I dare say Quetzalcoatlus would have killed and eaten fairly large animals in a similar way.

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  20. 20. Dartian 12:38 pm 08/21/2013

    Richard:
    I the bad winter of 1963 there were records of herons killing and eating cats.

    How does a 1-2 kg heron manage to kill and eat a cat that’s two to three times heavier? Source please!

    Link to this
  21. 21. Chabier G. 12:56 pm 08/21/2013

    Darren: Thank you, I’m really interested about Azhdarchid jaw muscles, so, if you might give me the references for these papers, I ‘d try to get them. The first question for me, when I see weird structures in extinct creatures is: How did it work?, or, even, How could it work?.
    Modern storks do fine with relatively weak jaw muscles, as they use their bills as spears to kill prey, in fact, they can even carry regular sticks and masses of lining to their nests . Cormorants size their slippery prey by biting, then, they need enhanced muscular masses closing their cutting jaws. Then, if Azhdarchid way of feeding was more like that of storks, as you have noted before, their skull anatomy has a lot of sense. Indeed, this skull anatomy would discard other ways of predation.

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  22. 22. Jerzy v. 3.0. 7:33 pm 08/21/2013

    Paleo art is terrible discipline – it ages so quickly!

    Anybody knows of examples of dinosaur art which have not aged?

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  23. 23. Jerzy v. 3.0. 7:37 pm 08/21/2013

    @19
    Incidentally, for some time I had a garden with a plague of cats catching all the small birds and a semi-tame Grey Heron. One day a particularly ugly and notorious cat came to the garden and tried to attack the heron. BTW, the same neighbor who owned that cat also started feeding that heron. The heron stabbed the cat near eye and quickly sent it running. I almost applauded!

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  24. 24. David Marjanović 7:57 pm 08/21/2013

    I grew up being told that it should be “x and I” but was corrected by Grammar Nazis several times both on Tet Zoo and while editing books and such.

    The trick is that and isn’t a preposition: for me, in me, to me, with me…

    So, it depends on the nearest preposition or verb: “he and I both thought” (unless you use me for emphasis) vs “for him and me”, “to him and me”, “with him and me”.

    If that’s not actually your intuition as a native speaker, I’ll be very surprised.

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  25. 25. John Harshman 8:41 pm 08/21/2013

    On the dreaded “X and I/me”: Modern English has a very few remnants of noun case, and I vs. me is one of them. “I” is subject case, “me” object case: direct objects, indirect objects, and objects of prepositions. But really, the simplest test is to substitute just “I/me” for “X and I/me”, and the wrong case should then sound weird to any native speaker. You would never write, “Me dub this the ‘Terrestrial Stalking hypothesis’”.

    Usually, in informal English, people use “me” when “I” is standard. But I in written English, the opposite is true, because you’re being oh so careful not to make the first error, and you end up putting “I” where it doesn’t belong; that has a name: hypercorrectness.

    But I have nothing to say at this time about demon pterosaurs other than that they’re very cool.

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  26. 26. Yodelling Cyclist 10:02 pm 08/21/2013

    Following on from the egg speculation: in a land dominated by r-strategists with precocious young, there must have been a lot of juveniles running around. Further, with creatures as rapidly and efficiently mobile as these Azhdarchids it might be possible to skip from hemisphere to hemisphere, hatching season to hatching season, picking off juveniles, along with anything else of appropriate size. Any seasonal congregation of small to medium sized animals anywhere on the planet could be held at risk – anadromous fish, mass turtle hatchings, seasonal seabird colonies (maybe a good reason for hesperornithids to give birth at sea ;-) ), and anything else one can think of (I may be being over influenced by Walking with Dinosaurs’ sauropodlets). It could explain why it’s so hard to tie Azhdarchids down to a single feeding mechanism, as they switch from one seasonal food source to another across a whole planet.

    All just amusing speculation.

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  27. 27. Elypha 10:11 pm 08/21/2013

    Awesome as always, Darren.
    Just an observation: I think you meant to write “Richard Orr” instead of “David Orr” in caption of the second image depicting the demonic Quetzies.

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  28. 28. llewelly 10:40 pm 08/21/2013

    Since the bite strength issue has come up again, I went and re-read the hornbill articles:

    http://scienceblogs.com/tetrapodzoology/2011/06/24/when-hornbills-bite/

    Until more scientific work it seems that both hornbills and stork have weak bites, and thus, a weak bite is consistent with the terrestrial stalker Quetzalcoatlus feeding hypothesis.

    (I do wonder, though it is not directly relevant, what the jaw strength and neck strength of frigate birds and shoebills was, and how do their different jaws and necks compare to Quetzalcoatlus. But they probably engage in too much piscivory to be good comparisons.)

    What is less clear (at least to me) is neck strength. Did Quetzalcoatlus have the neck strength to spear the hearts and rip out the tongues of over-eager grammar pedants?

    Or did taking Homo pedantus as prey not occur the evolution of highly specialized megaazhdarchid predators during the late pterozoic, many scores of millions of years later?

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  29. 29. SciaticPain 11:26 pm 08/21/2013

    I agree Yodelling Cyclist. I imagine azhdarchids as the bane of colony nesting critters in the Cretaceous. Interesting idea of migrating across hemispheres.

    I do recall reference to azhdarchid material from the two medicine formation of Montana (Egg Mountain, Maisaura etc). Certainly suggestive.

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  30. 30. Dartian 1:46 am 08/22/2013

    Jerzy:
    The heron stabbed the cat near eye and quickly sent it running.

    So the cat not only survived but possibly wasn’t even that seriously injured? Your anecdote does not shed any light on the question whether (a presumably starving and emaciated) Ardea cinerea truly is capable of subduing, killing and eating a mammalian carnivore significantly larger than itself. I want to see a credible first-hand source before I believe that such a thing is possible. (Is it certain that they really meant to say ‘cats’ and not ‘rats’ in 1963?)

    John:
    Usually, in informal English, people use “me” when “I” is standard. But I in written English, the opposite is true, because you’re being oh so careful not to make the first error, and you end up putting “I” where it doesn’t belong

    “Me fail English? That’s unpossible.” ;)

    Yodelling Cyclist:
    there must have been a lot of juveniles running around

    But the young dinosaurs, like the eggs, would in most cases probably also have been protected by their parents. In the case they were left to fend for themselves (like the hypothetical WWD sauropodlets), they probably would have dispersed and scattered quickly and tried to remain hidden as much as possible. In either case, under normal circumstances there would presumably not have been any large concentrations of unprotected baby dinosaurs available for the azhdarchids to feed on at leisure.

    Also, the large size of the azhdarchids would seem to be a suboptimal trait for a nest robber – they would be very conspicuous up in the air and it would be hard for them to approach, say, a nesting colony of hadrosaurs without being detected well in advance.

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  31. 31. Chabier G. 2:29 am 08/22/2013

    About herons and cats, once I was stabbed between the eyes by an emaciated purple heron, it made me only a scratch. Obviously, its target was one of my eyes, but it was too weak. An emaciated heron is a poor enemy, I can’t believe it can kill a cat, even a grey heron in good condition hasn’t got enough strength to jab a cat reaching vital organs, and the cat would not remain quiet, waiting for the next strike…
    After years fighting against the big fake of “livestock killer vultures”, I’m rather skeptic about all these unusual acts of predation.

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  32. 32. Yodelling Cyclist 3:50 am 08/22/2013

    Hello Dartian,

    I am, of course, speculating wildly and without formal training in the subject area, as is my wont. I actually think that my scenario works if the juveniles scatter – if the mega fauna are practising r type reproduction, then at some point in the year (assuming again seasonal breeding) the environment is going to be full of little ones. Sure, little ones are trying to hide, but still around, trying to hide in amongst the ferns and the bushes, maybe even into the woodland. So along comes a big stalking pterosaur that flew in all the way from sunny Texas to root them out of their hidey-holes. After all, mass mortality among the young lies at the heart of r selection. Oh and even if the wee ones make it to the woods, modern elephants seem to think that thick forest isn’t a big problem. Admittedly, a giant pterosaur would be grounded, but maybe it would be worth it for a snack. Just think of it as being a rich hunting ground full of inexperienced juveniles, rather than infants packed cheek by jowel in a colony, and it’s still worth flying in.

    When you state that the young, like the eggs, would be protected by the adults – well, maybe. Personally I rather suspect that talk of dinosaurs having either precocial or altricial offspring is a little misleading, and I know I fell into the trap above. I would imagine there would actually be the same spread of behaviour that we see in modern birds and crocodiles, with species falling at various points in the continuum between harris hawks and megapodes. You also have to reflect that there are a lot of terrestrial species significantly smaller than Q. Northropi, where defending the young is equivalent to going on the menu yourself.

    Think of it like modern swallows, except instead of seasonal insect gluts and feeding on the wing, the azdharcids are showing up to pick off the seasonal glut of juvenile mega fauna, stalking around, picking them off from hiding or snatching one and then bolting for it to get away from the parents. Actually Mark Witton has a blog article where he mentions that in his opinion azdharcids would be capable of quite a speedy launch-and-accelerate manoeuvre. Maybe this is the grab-the-kid-and-run-for-it adaptation (taking speculation way too damn far now). At least it lets me end this paragraph by saying that the these animals would then be flying – like a bat out of hell.

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  33. 33. Dartian 4:54 am 08/22/2013

    Yodelling Cyclist: No harm in speculating, especially if it’s of the sensible kind (as yours tends to be). I’m just making counterarguments for the sake of a balanced discussion.

    modern elephants seem to think that thick forest isn’t a big problem

    Elephants are not a good analogy here; compared to azhdarchids they’re built like bulldozers. Think giraffe instead. Or, better still, extant marabou storks. They are ecomorphologically speaking perhaps the closest thing we have today to azhdarchid pterosaurs, and they do not venture into dense vegetation because they’re not anatomically well suited for moving in such habitat (although they’re much smaller than the largest azhdarchids). In particular, in times of danger they would have great difficulties in trying to escape by flying away. What would have happened to an azhdarchid that entered deep into a forest and then run into a hungry tyrannosaurid there?

    there would actually be the same spread of behaviour that we see in modern birds and crocodiles, with species falling at various points in the continuum between harris hawks and megapodes

    I think megapodes are a bit of a red herring in these kinds of discussions, really. They alone (or at least almost alone*) are the one big exception among extant birds – virtually all other avians practise significantly more intensive forms of brood care, which includes guarding and protecting the young. (This even applies to brood parasite species, such as cuckoos and cowbirds; in their case, they just let members of some other species take care of their young.) To say that avian brood care includes a wide range of strategies is a bit of an overstatement considering that the ‘no care beyond incubation’-category inludes just a tiny handful of taxa.

    * There is also the South American brood-parasite anatid, the black-headed duck Heteronetta atricapilla; its ducklings fend for themselves as soon as they’ve hatched. But apart from that species and the megapodes, the list of extant birds which have young that do not need care by their parents is pretty short.

    Link to this
  34. 34. Yodelling Cyclist 5:27 am 08/22/2013

    Hello Dartian,

    Well, I shall continue my side and let the spectators decide.

    As for the forest elephants: yes, sure , I was being more than a little flippant, and I concede that an azdharcid would be cramped in the timber, but then again, okapis…

    What would have happened to an azhdarchid that entered deep into a forest and then run into a hungry tyrannosaurid there?

    There would be a comedy chase in which an azdharcid tries to avoid falling over its wings while the tyrannosaurid battles to keep its tail from smashing into stuff and tripping over a log? No idea, in short, it’s not something I insist on. I still imagine there would be enough infants trying to lurk in the long ferns, maybe cached like modern infant rabbits, maybe getting separated from parents while foraging, maybe just getting out-and-out snatched by a winged monster that just swooped out of the sky like a leathery Ju-88 sans siren. Remember dinosaurs don’t seem to have bread like modern ungulates, having one or two offspring a year, egg clutches are large, lots of young are being produced, normally that means low amounts of care subsequently (and a smorgasbord for predators).

    I think megapodes are a bit of a red herring in these kinds of discussions, really.

    I don’t. It shows the modern extremes of the spectrum. The extremes that are possible for a therapod to go to. Just because it’s rare now doesn’t mean it was rare then, this is a very different world with a very different threat environment, and the animals we are discussing fill radically different ecological niches (extant birds have nothing to compare with, say sauropods or ceratopsians). It’s worth bearing in mind that precocial to altricial is a continuous spectrum, and extinct dinosaurs and pterosaurs could lie pretty much anywhere on it. Going back to clutch size, I seem to recall long ago having one of these discussions (i.e. one where I went way to far with far too few data) with David Marjanović in which we discussed sauropod reproduction and average clutch size. I seem to recall that either he didn’t know – or no one at all knows – what an average would be , but IIRC we were using double figures to discuss clutch sizes. I know I’m like a broken record but I think this may be a good argument for r-selection, and low parental care is concomitant with the large clutch size (less is invested in nurturing, more in producing).

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  35. 35. Yodelling Cyclist 5:32 am 08/22/2013

    So how does the black headed duck brood parasitism work? Do the parents dump the eggs on unsuspecting marks, and then the young run off to the water after hatching without taking advantage of altricial care by the victims? Seems a bit odd to be that precocious AND be a brood parasite…

    Link to this
  36. 36. naishd 6:05 am 08/22/2013

    Thanks for all of these interesting comments. And sorry to David Orr for accidentally using his name… ha.

    Darren

    Link to this
  37. 37. Dartian 7:56 am 08/22/2013

    Yodelling Cyclist:
    So how does the black headed duck brood parasitism work? Do the parents dump the eggs on unsuspecting marks, and then the young run off to the water after hatching without taking advantage of altricial care by the victims?

    Pretty much, yes. The main factor influencing host nest choice would seem to be proximity to water.

    Seems a bit odd to be that precocious AND be a brood parasite…

    Well, that’s what you get if you’ve evolved from already-precocial ancestors. Besides, some of the black-headed duck’s potential hosts – e.g., gulls, raptors(!) – don’t feed their own young with things that the ducklings could eat, so the duckling would starve if it remained in the nest of such hosts.

    Incidentally, intraspecific brood parasitism is very common in many species of anatids. The black-headed duck has just taken it one step further by becoming an interspecific brood parasite.

    Link to this
  38. 38. Yodelling Cyclist 9:32 am 08/22/2013

    I’m now stuck with the image of a pair of ospreys (that is what my mind threw up) chasing a duckling around a pond trying to feed it fish…..

    It makes me laugh, anyway. Thanks for that one.

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  39. 39. John Harshman 11:37 am 08/22/2013

    Incidentally, intraspecific brood parasitism is very common in many species of anatids. The black-headed duck has just taken it one step further by becoming an interspecific brood parasite.

    Actually, facultative interspecific brood parasitism is common in ducks, too. The black-headed duck has just taken it one step further by becoming an obligate interspecific brood parasite. There is, by the way, no evidence that any of this “parasitism” harms the brood in any way.

    Link to this
  40. 40. Chris Bennett 4:52 pm 08/22/2013

    Who will describe Quetzalcoatlus? Darren states that it is unsure what will happen, but when Wann Langston died it seemed pretty clear what would happen. Wann contacted me in 2006 and asked me to coauthor the full description of the referred specimens, and I happily agreed. I went down to Austin to start work but little got done because Wann’s priority was with crocodilians rather than pterosaurs and I was not about to tell a man in his 80′s what to do. Shortly before he died, Wann contacted me and asked me to complete the monographic description of the referred specimens and submit it for publication within one year. Again I agreed. Wann died in April and I planned to go to Austin to work on the materials in June, but the curator, Tim Rowe, would not let me. Although Wann had assured me that he had laid out all the pertinent papers and specimens in his office so it would be easy for me to pick up where he left off, Rowe claimed that it would take them a long time to sort through the office contents. I prefer to believe Wann and have no confidence that Rowe will ever let me work on the monograph. So now the statement that we do not know what will happen is true. Some may want to criticize Langston for sitting on the material for so long and not publishing, but if his final wishes for the material were respected, a thorough monograph would have been submitted for publication by the Summer of 2014. Langston is no longer responsible for any delays, and from now on full responsibility for whatever does or does not happen with Quetzalcoatlus is on Tim Rowe.

    Chris

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  41. 41. David Marjanović 7:41 pm 08/22/2013

    …Why can’t Rowe and you simply collaborate?

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  42. 42. abrashtx 10:32 am 08/23/2013

    “Mark Witton and I dub this the ‘terrestrial stalking hypothesis’…” Professional “grammar Nazi” here. You use “I” when you are the subject of the sentence, and “me” if you’re the object. In this case, “Mark Witton and I” is correct, bc y’all are the subject of the sentence (the ones actually performing an action). However, consider this sentence: “This azhdarchid paper gave Mark Witton and me a headache.” You and Mark are now the SUBJECT of the sentence, so it’s correct to use “me”. Don’t get me started on “its” and “it’s.”

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  43. 43. Halbred 4:09 pm 08/23/2013

    Rowe sounds like the kind of guy you would NOT want to collaborate with. Maybe we should start a letter-writing campaign?

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  44. 44. David Marjanović 5:48 am 08/24/2013

    You and Mark are now the SUBJECT of the sentence

    …by which you mean “object”. The subject is “this azhdarchid paper”.

    The Bierce-Hartman-McKean-Skitt Law of Prescriptivist Retaliation states that any article or statement about correct grammar, punctuation, or spelling is bound to contain at least one eror. :-)

    Maybe we should start a letter-writing campaign?

    Let’s hear Rowe’s side first.

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  45. 45. Yodelling Cyclist 8:08 pm 08/24/2013

    Nest parasitism amongst non-avian dinosaurs. Another fun thought.

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  46. 46. Dartian 3:13 pm 09/7/2013

    A very late contribution to this thread:

    Still related to those earlier-mentioned alleged instances of grey herons killing and eating cats; here is a video of a black stork Ciconia nigra that’s trying to defend its nest against a pine marten Martes martes. Black storks are roughly comparable in size to grey herons – in fact, they are on average even larger (circa 3 kg). Pine martens, on the other hand, are on average smaller than ordinary domestic cats (less than 2 kg).

    In other words, the stork in this video has both a size advantage and a strong motivation (not predation, but nest defence), but it still doesn’t seem to be able to seriously injure the marten. The fight ends when the marten has had enough and counterattacks the bird, only to fall off the nest.

    After seeing that video, I’m even more sceptical of claims of cat-killing herons…

    Link to this

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