kulindadromeus

Kulindadromeus zabaikalicus, the first known fluffy ornithischian dinosaur. Only officially announced last week, this little 1.5m long (~5ft) Jurassic critter is an incredibly significant find. Until now all known examples of feathered dinosaurs have been members of the theropod branch, but Kulindadromeus is a basal neornithischian, much more closely related to hadrosaurs, ceratopsians and pachycephalosaurs.

Two other ornithischians, Tianyulong and Psittacosaurus, were previously known to have sported quill-like bristles, but this new find is the first example of actual filamentous “dinofuzz” in the group. The fossils of Kulindadromeus preserve three different types of feathery integument – hair-like filaments on the body, downy tufts on the upper limbs, and strange “ribbon-like” feathers on its shins – as well as scaly skin on the tail and lower limbs.

The idea that fuzzy ‘protofeather’-like structures might be ancestral to all dinosaurs (or maybe even deeper in the archosauria) is starting to look increasingly likely…

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Who was the earliest bird: Archaeopteryx, as has long been thought, or Aurornis, a newly-described Chinese paravian? Nature News explores this issue in a new article that features this illustration of these two dinobirds facing off in a conceptual battle for status.

Contra the Nature article, and while the true phylogenetic position of Archaeopteryx is certainly a fascinating issue and deserves resolution, the reality is that it does not matter whether good ol’ Archie was a bird or something very, very similar to a bird. Modern phylogenetics has rendered the distinction logically irrelevant: whether Archaeopteryx is the first “bird” is now an issue of semantics more than one of science. So let’s try to cut back on the uproar over who was truly the earliest bird—there are enough worms to go around.

Gouache on artboard, 16" x 20", processed in CS4.
Available as a print.

Also pictured: Kulindadromeus, a basal neornithischian covered in voluminous feather-like structures, and Zanabazar, a late Cretaceous Mongolian troodontid.

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Orodromeus makelai

[I made a soundtrack for this painting, which can be heard at my SoundCloud page, here.]

Montana, sunrise in the Campanian Age of the Late Cretaceous:

Sol’s rays illuminate morning fog and low clouds over the ancient Cordilleran highlands, and an Orodromeus, Mountain Runner, makes its way east towards the Late Cretaceous Western Interior Seaway that bisects the continent. Recent volcanism has startled and scattered the herd, and covered a swath of local vegetation in ash; a consequence of orogenesis, mountain building, the collision of tectonic plates causing upthrust that will eventually become known as the modern Rocky Mountains in 75 million years. Instinct drives the runner to the ancestral nesting grounds at Egg Mountain, closer to the prehistoric sea’s shores.

The journey east holds the potential for a new mate, and dangers, too: A group of large, hungry Daspletosaurus has been prowling these foothills and would surely devour the Mountain Runner in a few bites if they get the chance - but the runner’s senses are keen, and strong hind limbs swiftly propel its light 2.5 meter body. Troodon also prove threatening, with their sharp eyes, grasping claws, wounding teeth and relatively large brains. Mountain Runner narrowly escaped a Troodon two days ago, with a swift lash of its tail, lodging a quill in the Troodon’s snout and leaving it stunned long enough to accelerate away.

Egg Mountain will provide some safety: large, herbivorous Maiasaura make their nests there, too, and the nimble Mountain Runner will find staying out from underfoot easy enough compared to fleeing swift and toothy predators. With luck, the runner will be reunited with the herd, and find a mate…

In deep time, fossils of Orodromeus, Maiasaura, and their eggs and young will give paleontologists clues to dinosaur behavior. The grand cycles of the world continue with theme and variation, driving the evolution and extinction of whole clades of life, our shared natural history as organisms of Earth.

[Some speculation above, but hopefully within the realm of possibility. Please don’t use or reproduce the image or words without permission, and thanks for viewing, reading and listening!]

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Little ornithopods like Orodromeus don’t seem to get nearly enough attention in paleoart – they’re often just shown as prey for theropods, despite being pretty fascinating in their own right. Recently-discovered Kulindadromeus, an older relative of Orodromeus from Jurassic strata of Siberia, had some remarkably well-preserved, fuzzy-looking, feather-like fossilized integument. Dr. Dave Hone wrote a great article about it, and included some amazing images of the fossils and really excellent artistic reconstructions, which can be seen here.

Kulindadromeus is more closely related to Triceratops than to birds: the implications are quite intriguing, and this discovery will have artists seriously rethinking how Ornithischians are depicted from now on (including Orodromeus). Kulindadromeus gets my vote for the #1 spot on any lists featuring top dinosaur discoveries of 2014 (with a lot of strong competition – what a great year for dinosaurs!).

Check out Andrey Atuchin’s wonderful version of Kulindadromeus here; Tom Parker’s great fuzzy Orodromeus here; and Scott Hartman’s excellent skeletal drawing of Orodromeus at his page, here. Brian Franczak did a beautiful painting of Orodromeus, featured in The Audubon Society Pocket Guide to Familiar Dinosaurs (1993) which sits on my desk to this day. These artists (and many others – James Gurney and Wayne Barlowe come to mind), as well as the many paleontologists making discoveries in the field, helped inspire my painting of Orodromeus.

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I seem to have somehow acquired several thousand new Tumblr followers over the last few weeks; this has been a rather astonishing experience. Thank you all so much for the support, happy new year, and I hope you continue to enjoy the art!

Kulindadromeus zabaikalicus

Source: http://www.smh.com.au/content/dam/images/z/w/l/e/6/image.related.articleLeadwide.620x349.zwgap.png/1406234939426.jpg

NameKulindadromeus zabaikalicus 

Name Meaning: Zabaikal Kulinda Runner 

First Described: 2014 

Described By: Godefroit et al. 

ClassificationDinosauria, Ornithischa, Genasauria, Neornithischia

My Fourth Favorite Dinosaur 

When this dinosaur was discovered, it rapidly rose to the fourth position in my favorite list - and it’s obvious why. This dinosaur proves pretty clearly that feathers were synapomorphic for both Ornithischia and Saurischia (something I have been suggesting for years due to quills being found on another basal ornithischian, Tianyulong, as well as protofeathers found on Psittacosaurus, and the presence of feather protein genes in the crocodile genome, suggesting that protofeather-esque filaments are a trait of all of archosauria, based on cladistics. Genomes, man. Genomes.) It was found in teh ukureyskaya formation in Russia, which dates back to the middle to late Jurassic, about 169 to 144 million years ago in the Bajocian to Tithonian ages. It is known from a partial skeleton in rock that lead to amazing preservation of both feathers and scales. Now, this fossil was stolen and described as another species, Kulindapteryx, but this is not valid and should be ignored (curse you, BANDits.) 

Source: https://en.wikipedia.org/wiki/Kulindadromeus#mediaviewer/File:Kulindadromeus_by_Tom_Parker.png

Kulindadromeus was a bipedal runner, about 1.5 meters long, with a short head, short forelimbs, and long hindlimbs and tail. It had scales on the top of its tale and scales branching into feather like structures on the main part of the body. This fuzz all over the body are hair like filaments like stage 1 dino fuzz on Sinosauropteryx, and then another type is longer filaments on the upper arms and thighs like type three feathers, and then unique bundles of ribbon like structures on the upper lower legs that are made from parallel filaments. 

Source: Prehistoric-Birds (Give them a follow!) 

Kulindadromeus also had three types of scales: overlapping hexagonal scales on the lower shins, non-overlapping scales on the hands ankles and feet, and arched rectangular scales on the tail, forming rows. 

According to the science of evolutionary cladistics, the closer two clades are related to one another, the more likely any features shared by those clades was only evolved once, in their last common ancestor. More deviated groups - such as birds and bats - that share a feature evolved them separately. As such, the fact that crocodiles have a dormant feather gene (same protein) implies that the last common ancestor of both crocodiles and birds had feathers - and that’s just from genomics. Now, while this feature may have been lost in many archosaurian species - as fur is lost in many species of mammals - it is important that we now, as paleontologists, switch our line of thought from “scaled until proven otherwise,” to “feathered until proven otherwise.” The discovery of so many feathered or quilled theropods - as well as quite a few quilled and feathered ornithischians, now - only bolsters that claim. This is by far one of the most exciting discoveries of modern paleontology, and I can’t wait to see what more we find out about the connection between dinosaurs, birds, and feathers in the coming years. 

Source: 

https://en.wikipedia.org/wiki/Kulindadromeus

Shout out goes to prehistoric-birds, since I used their art!

Also, the moral of today’s story is NEVER TRUST A BANDIT 

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I currently have two original paintings for sale on my Etsy, if you’d like to surprise that dinosaur-lover in your life for the holiday season… (even if that dinosaur-lover is you. That’s okay, too.) 

Kulinadromeus (top) and Changyuraptor (bottom), two new feathered dinosaurs described in 2014, both in gouache on artboard. The Kulindadromeus was recently published in the Dec 7 issue of Nature, and the Changyuraptor currently graces the Wikipedia article on the dinosaur. Get ‘em now!

butthedogbeatmeoverthefence asked:

Hey big fan of your blog :) Basically I am in no way disagreeing that dinosaurs had feathers But if there is no thoroughly conclusive evidence that they did indeed have feathers, why is it considered silly to think that maybe they didn't?

Ah but the evidence is conclusive. It’s as conclusive as the evidence for fossil birds having feathers. We have direct imprints of the feather filaments in the fossils. 

Some examples: 

Feathers along the back (Sinosauropteryx)

Feathers along the hand (Kulindadromeus

Feathers… everywhere (Microraptor

Quill knobs - a feature found on bird bones that is direct evidence for feathers (Velociraptor

And in many dinosaurs that do not have conclusive, direct evidence for having feathers, such as Deinonychus, their overall similarity to dinosaurs we know have feathers and their close relationship to them means that to depict them as being scaly would be as silly as depicting fossil deer as furless. 

There are some dinosaurs with evidence for scales like hadrosaurids and Carnotaurus, and some with inconclusive evidence, but for many dinosaurs, given Kulindadromeus, there is far less reason to depict them without feathers than with. It’s like mammals and fur. Some lost them, but certainly not all, and certainly not the small ones that are closely related to birds, like Deinonychus

Kulindodromaeus (sic) by Antresoll

The Kulindadromeus cock had spent five weeks laying claim to his spot in the forest. He’d chosen a wide furrow between the trees where there’d be enough room for a lek of females to gather. His rivals were strong and dealt some heavy kicks, but he maintained his lien and cleaned it fastidiously.

Before the females arrived, all the males in the wood bent their heads high and clicked and clucked, their popping rhythms sounding like dozens of tennis matches. Thwack! Thwock! Thwack! Thwock! The hens were delighted and reported in chirping mobs. Then the hen-swarms would break into groups of two or three or even four to become an audience for the cock of their choice.

Two hens came to his courtyard. Two was more than one, so he was pleased and danced for their patronage, head still back, body shuddering, ping-pong song loud, tail tip flicking with the rhythm. The females accepted him. Copulation was short—seven seconds with each hen—an anticlimactic climax to weeks of fights and courting. The females stayed with him until it came time to go to the nesting grounds, a little harem of two with a woodland sultan, warming each other when the April nights went cold.

Thoughts on Kulindadromeus' integrument

Thoughts on Kulindadromeus’ integrument

JULY 27, 2014

So Kulindadromeus‘ paper is out, and so is the description of it’s feather and “scale” types. As Matt Martyniuk pointed out long before, bird “scales” are actually stunted feathers, and since filamental integrument is known to be present elsewhere in archosaurs (pterosaur pycnofibrils and alligator “feather genes”), this adds a layer of complexity to our understanding on the evolution of not just feathers, but sauropsid integrument as a whole. Kulindadromeus thus is not just an example of a feathered dinosaur as far away from birds as possible phylogenetically, it is also a window to the proccess of the conversion of feathers into scales, and thus perhaps an example of a process that goes as far back as the earliest archosaurs.

Integrument types

Godeforit et al. 2014 describes six different types of integrument in Kulindadromeus: three are filamental structures, identifiable as “feathers”, while another three are “scales”:

- Simple, hair like filaments, up to three centimeters long, that cover the torso, neck and head (possibly also most of the tail; see below). Similar to the simplest theropod feathers, Tianyulong‘s fuzz and pterosaur pycnofibrils, these are most likely the “original” integrument for archosaurs as a whole.

- What appears to be the “type 3″ feathers in the famous feather evolution schematics (already known from a few theropods), composed of six or seven filaments projecting from a single base plate (the “scales branching into feathers” that were originally advertised). The filaments are as long as 1.5 centimeters, the plates are organised in an hexagonal pattern but not overlapping. They cover primarily the upper arm and thigh, which in life most likely would have looked quite fluffy.

- An unique type of “feather”, composed of bundles of six or seven ribbon-like structures, in turn composed as as much as ten parallel filaments up to 0.1 millimeters wide, as long as two centimeters. By far the most complex integrumental structures seen in the animal, they are found exclusively on the upper lower legs, and almost certainly were display devices, their rarity and location implicating a minimal, if any, role in thermoregulation.

- Small (less than a millimeter in cross section), round, non-overlapping scales, covering the hands and feet (including the digitigrade ankles). These are classical examples of reticulate scales (reticulae), seen in modern birds, most non-avian dinosaurs (including ornithopods like hadrosaurs) and pterosaur foot pads, and are proven to be “stunted” simple feathers (in the case of pterosaurs, stunted pycnofibrils), as evidenced by their prevalence in foot pads and other dystal areas of the limb, less in need of insulation and more in need of protection.

- Overlaping hexagonal scales, up to 3.5 millimeters in diameter. They are found only in the lower shins.

- Another unique integrumental structure, a series of overlapping, rectangular scales that cover the upperside of the tail (these are the only “scales” known outside of the limbs, and based on the decomposition patterns in other feathered dinosaurs like Sinosauropteryx, this may mean that the rest of the tail was covered by feathers). They are as long as two centimeters, having a thickness of less than 0.1 millimeter, and a largely smooth surface with the exception of a small spur projecting forwards, that covers the trailing edge of the preceding scale. They are arranged in five longitudinal rows, imbricated thanks to their overlapping.

Feather complexity in the limbs vs simple body feathers

Pedopenna reconstruction. We now know that many theropods had exuberant “wings” on the limbs; could complex feathers as a whole have originated as display devices on the limbs?

The first thing you’ll notice about Kulindadromeus‘ feathers is a dichotomy between those covering the body and those covering the limbs. The body coat is composed by the most simple form of feather known, while the limbs (an specific areas of the limbs at that) are the ones to display the more complex feathers. Given the priority of the torso over the limbs in terms of insulation, as well as the extremely restricted location of the “ribbon bundle” feathers, it seems very plausible that the complex limb feathers didn’t evolve in response to thermoregulatory needs.

Instead, it seems more likely that Kulindadromeus‘ branched feathers were used for ornamental purposes, particularly the “ribbon bundle” feathers, whose complexity and restricted location is consistent with the tendencies seen in other flamboyant dinosaur feathers. Thus, branched feathers originated as display devices, and only latter were reapropriated into an insulatory role. Their absence in the other known feathered ornithischians like Tianyulong and Psittacosaurusseems to give credence to this idea: in both of these animals, simpler quills are known, forming a dense coat in the former, while branched feathers are nowhere to be seen, in spite of their inferred usefulness as insulation devices.

This trend may have indeed been the norm for the whole of Dinosauria: in theropods as derived as Maniraptora, we often see simpler body plumage, while the limbs provide “wings” composed of more elaborate feathers. In Kulindadromeus, both the forelimbs and hindlimbs possess branched feathers, and we know that hindwings were probably present in theropods as basal asConcavenator (see Matt Martyniuk’s discussion on it’s pedal scutes), offering thus a further insight into the evolution of the wing.

“Scales”: stunted simple feathers, stunted dorsal scutes, and something else?

As evidenced by many domestic pigeons and chickens with pedal remiges, avian scutes are actually stunted flight feathers. Could Kulindadromeus’ bizarre dorsal scutes be the stunted version of the quills seen in Psittacosaurus and Tianyulong?

Kulindadromeus‘ “scales” are every bit worthy of discussion as the filamental feathers, unique as they are and as insightful into the evolution of archosaurian integrument. Kulindadromeus‘ presents clear reticulae in the feet and hands, “scales” that are proven to be stunted simple feathers/pycnofibrils, and seen most often in the foot pads of pterosaurs and theropods, as well as more extensively in the limbs of birds and across the whole body in hadrosaurs, ankylosaurs, sauropods and ceratopsians. Kulindadromeus, therefore, showcases an intermediary state between the inferred fully-fuzzy early ornithischians and (mostly?) featherless, reticulae covered derived forms: it’s hands and feet, less in need of insulation and in need of protection as the animal digs and forages on the ground, have stunted the dystal feathers into round, non-overlapping “scales”, while the rest of the body remains fluffy and warm. As seen in birds like owls, however, reticulae are easily reconverted into filamental feathers, so ornithischians most surely switched between reticulae and true feathers countless times across their evolutionary history.

More perplexing, however, are Kulindadromeus‘ scutes. These structures, thin and clearly keratinous, are not osteoderms like the “scutes” of crocodiles and ankylosaurs, representing a form of scale unique among sauropsids. Forming flat, overlapping surfaces, they are most easily comparable to the pedal scutes of birds, and indeed may share a similar origin. The other feathered ornithischians, TianiyulongPsittacosaurus and possibly Triceratops, all possess long, rigid quills across the back and tail upperside; given that the former’s a non-neornithischian and the latter two are ceratopsians, these structures must have been an ancestral condition for ornithopods according to phylogenetic bracketing, since ceratopsians are closer to ornithopods than heterodontosaurids are.

Could thus the scutes be simply stunted dorsal quills, like avian pedal scutes are stunted flight feathers? This seems most likely the case; phylogenetic bracketing aside, both structures are too similar to have their similarities dismissed, both being flat, overlapping “scales” derived from rigid quills. Equally interesting is the presence of a vestigial spur in Kulindadromeus‘ dorsal scutes, further implying their derivation from quills.

Tianyulong and Psittacosaurus by Jaime A. Headden. Both possess dorsal quills, but one is closer to Kulindadromeus than the other; phylogenetic bracketing ensues.

Of interest are the final group of “scales”, the hexagonal, overlapping structures in the lower shins. Are these stunted feathers as well? Reticulae seem to develop from both unbranched feathers and down, so Kulindadromeus‘ reticulae probably evolved from the branched limb feathers. Are these then true scales, a relic from Kulindadromeus‘ distant non-feathered ancestors? Only time will tell, though personally I don’t think so; we can’t even tell if archosaurs outside of ornithodira inherited scales that aren’t modified feathers, since alligators have the “feather genes”.

Conclusion

Kulindadromeus offers a powerful insight into the schematics of integrument evolution in not just dinosaurs, but archosaurs as a whole. It’s numerous types of feathers and “scales” pretty much confirm trends suspected for decades, and may even clarify several processes previously unanswerable. More research will be needed, but the evidence we have clearly is helpful in our general understanding.

Refferences

- Pascal Godefroit, Sofia M. Sinitsa, Danielle Dhouailly, Yuri L. Bolotsky, Alexander V. Sizov, Maria E. McNamara, Michael J. Benton & Paul Spagna, 2014, “A Jurassic ornithischian dinosaur from Siberia with both feathers and scales”

- V.R. Alifanov & S.V. Saveliev, 2014, “Two new ornithischian dinosaurs (Hypsilophodontia, Ornithopoda) from the Late Jurassic of Russia”

- Zheng, Xiao-Ting; You, Hai-Lu; Xu, Xing; Dong, Zhi-Ming (19 March 2009). “An Early Cretaceous heterodontosaurid dinosaur with filamentous integumentary structures”

- Bell, P. R. (2012). Standardized terminology and potential taxonomic utility for hadrosaurid skin impressions: a case study for Saurolophus from Canada and Mongolia.

- Dhouailly, D. (2009). A new scenario for the evolutionary origin of hair, feather, and avian scales.

- El-Sayyad, H. I., Fouda, Y. A., Khalifa, S. A., AL-Gebaly, A. S., & El-Sayyad, O. K. (2013). Studies on epidermal appendages of chick embryos.

- Sawyer, R. H., & Knapp, L. W. (2003). Avian skin development and the evolutionary origin of feathers. Journal of Experimental Zoology Part B: Molecular and Developmental Evolution

- Zheng, X., Zhou, Z., Wang, X., Zhang, F., Zhang, X., Wang, Y., … & Xu, X. (2013). Hind wings in basal birds and the evolution of leg feathers.

- Perkins, S.; Csotonyi, Julius T. (2010). “Dressing Up Dinos”

http://news.harvard.edu/gazette/story/2010/11/bird-meet-cousin-alligator/

captlego13 replied to your post “Hey big fan of your blog :) Basically I am in no way disagreeing that…”

Well the early dinosaurs didn’t have feathers as much I’d imagine I mean they got them around the Jurassic right?

Actually, no. The discovery of Kulindadromeus showed that feathers were an ancestral trait in all of Dinosauria, so they’re at least as old as the Triassic. 

One of my favorite hypotheses is that protofeather integuments evolved to help dinosaurian ancestors cope with the climate change involved in the Permian extinction and later Earth recovery, but that’s just a hypothesis. 

Kulindadromeus, the fluffy little critter that it is, roams the forest of horsetails. It is early in the morning; the sunlight peeking from the distant mountains illuminates the highest treetops. Mayflies are ascending from the surface of the pond, only to be seized within the jaws of this diminutive herbivore. As herbivorous as it may be, Kulindadromeus won’t pass up a nutritious snack.

Small notostracans emerge from the water, crawling slowly towards the edge. The ever-curious Kulindadromeus picks one of them up with its foot. It vigorously squrims; Kulindadromeus, startled, drops the invertebrate into the water, where it slowly trudges away.

Another older Kulindadromeus watches from the horsetails as it slowly nibbles on a stalk. It is not amused by the juvenile’s antics. One day, its distant relative will forget what a horsetail is. For now, it savours the tenderness of the horsetail in all its feathered glory.


While I’m sure huge parts of the internet are currently going mad over the new ornithischian Kulindadromeus and the implications for fuzzy dinosaurs (or otherwise) there current crop of pictures available isn’t that great. Inevitably those in the paper are small and crammed into the limited space (in the main paper at least, I’ve not yet got hold of the supplementary files and am writing this before the paper is released) and the press images are focused on the beautiful life reconstructions. However, Pascal Godefroit was kind enough to pass onto me a pile of images that he said I could use. Many have made their way onto my Guardian piece on the subject, but even there they have to stay small to fit the website’s style and some of the detail is lacking, so I’ll put them up here instead.

Obviously these images come directly from Pascal and are copyright to him and his team and should not be reproduced without his direct permission. Anyway, they do show some nice details of various parts of these specimens and the different integumentary structures (both scales and filaments) rather well and I imagine will be of some interest. I won’t add any more description here since I’ve already written a couple of thousand words on this animal today and I suspect most readers will be angling for the paper to do their detailed reading anyway. Enjoy.

Multiple filaments associated with the femur

Multiple filaments associated with the humerus.

Small scales associated with the pes.

Small filaments associated with the skull.

Filaments at the proximal tibia.

Scales on the distal tibia.

Close up of tooth series.

Huge thanks to Pascal for lending me these images and letting me put them online and obviously my congratulations on the discovery.