troodontid and kea parrot
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Papiliovenator neimengguensis Pei et al., 2021 (new genus and species)
(Skull of Papiliovenator neimengguensis, from Pei et al., 2021)
Meaning of name: Papiliovenator = butterfly hunter [referring to the “butterfly-like” shape of its first two back vertebrae]; neimengguensis = from Inner Mongolia
Age: Late Cretaceous (Campanian)
Where found: Wulansuhai Formation, Inner Mongolia, China
How much is known: Partial skeleton of one individual, including a nearly complete skull and fragmentary limb bones.
Notes: Papiliovenator was a troodontid, a group of relatively small, bird-like theropods. Two other troodontids have previously been reported from the Wulansuhai Formation, Philovenator (which had narrower feet than Papiliovenator) and Linhevenator (which was larger than Papiliovenator but had proportionately shorter upper arms).
Papiliovenator was unusual among Late Cretaceous troodontids in having a fairly deep, short-snouted skull. In this way, it was more similar to older troodontids from the Early Cretaceous. Most other Late Cretaceous troodontids with preserved skull material exhibit a very long, low snout, except for the smaller Almas from Mongolia.
Based on microscopic examination of its internal bone structure, the type specimen of Papiliovenator had not finished growing at the time of its death, though its rate of growth had been slowing down.
(Neck and back vertebrae of Papiliovenator neimengguensis, from Pei et al., 2021; note the “butterfly-like” shape of the second back vertebra [d2])
Reference: Pei, R., Y. Qin, A. Wen, Q. Zhao, Z. Wang, Z. Liu, W. Guo, P. Liu, W. Ye, L. Wang, Z. Yin, R. Dai, and X. Xu. 2021. A new troodontid from the Upper Cretaceous Gobi Basin of Inner Mongolia, China. Cretaceous Research advance online publication. doi: 10.1016/j.cretres.2021.105052
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Day 26: Troodontidae; Hesperonithoides.
Formerly known as Lori, the Morrison Troodontid.
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Can you do some pics for troodontids that formerly classified as Troodon? (Pectinodon, Albertavenator, Stenonychosaurus and Latenivenatrix...)
Oh yeah, Troodon’s back to being a dubious/invalid name now, isn’t it?
I might do at least one of those ones sometime.
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Everything is irrelevant when Chicxulub impactor struck the earth.
Two colored linocut of troodons taking a walk at winter night, school work which I had to finish using photoshop 'cause big linoworks are so friking hard to make when there isn't exactly that big tools I really would have needed xd
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So there’s a challenge being run by Wyatt Andrews on twitter and instagram called #DinosThroughThe Decades, the aim being to compile a timeline of our scientific understanding of one prehistoric species as represented through palaeoart! I decided to do Stegoceras validum, since I feel like it’s gone through a lot of changes that aren’t appreciated as they should be! And so, here’s my breakdown of each drawing in this timeline:
The year in which Stegoceras was described, as Stegoceras validus, by Lawrence Lambe. The identity of the fossil was pretty much completely up in the air at the time, since all we had of it at that point was the dome of the skull:
One of the conclusions that Lambe reached, and the one I’ve gone with here, is that the dome was the base of a large single horn on the snout of a ceratopsian dinosaur. There is sadly no actual palaeoart depicting Stegoceras like this, so I based my reconstruction heavily on Charles Knight’s beautiful ceratopsian illustrations from the 1890s and 1900s.
By 1918, Lambe was now suggesting that Stegoceras was not a ceratopsian, but a member of the group stegosauria, which included ankylosaurs and stegosaurs and is now known as thyreophora. He even erected a new clade for Stegoceras, psalisauridae, which did not last long.
This was probably the toughest one for me to work out since the brief is basically “a thick-headed 1910s-style generic thyreophoran”, and I ended up working mostly from Knight’s Stegosaurus and improvising the armour. That said, it’s a wonderfully weird concept and it’s one of my favourite end products!
We finally know what the rest of Stegoceras looks like! Charles Gilmore described a complete skull and partial skeleton of Stegoceras, and very helpfully for me it included a skeletal diagram!
But yes, the small birdlike elephant in the room: Gilmore’s description reassigned our beautiful bumpy-head boy to the now-considered-dubious tooth taxon “Troodon”. This ended up with the kinda confusing situation of having what is now known as pachychephalosauridae being grouped under the name “troodontidae”, which now refers to a clade of dromaeosaurs. Even after the clade name was changed, new pachycephalosaurs were still being described as species of “Troodon” all the way into the 1950s!
The way that palaeontology viewed dinosaurs was beginning to alter during the 70s and 80s, and dinosaurs were starting to run faster and lift their tails up off the ground. The last few decades had been good for pachycephalosauridae too, with new fossils showing a much greater scope of the group’s diversity in North America and Asia, and “Troodon” finally being ejected from the group as recently as 1987 by Phil Currie.
My main inspiration for this one was these awkward dinosaur book illustrations from around this era that just seem kinda off. Either it’s something about how cylindrical and formless the limbs are, or the stiffness in the pose, but I find them charmingly odd. They look very much like plastic dinosaur toys.
The Dinosaur Revolution is in full swing at this point, and dinosaurs are tending to look leaner, meaner, and kinda in need of a decent meal. The 90s and the 2000s really form a bit of a single era in dinosaur palaeoart, with dinosaurs in wiry muscle and skin and not much else, often adorned with spikes and osteoderms and the occasional single spiny dewlap. It was a weird time and of all of them this one was the hardest to draw faithfully and correctly without feeling like I was making a parody.
And finally, my comfort zone! The impact of the book All Yesterdays on the trajectory of modern palaeoart is truly hard to understate, since it basically pushed weird, experimental palaeoart into the mainstream palaeo consciousness. Moving on from the almost literally bare bones dinosaurs of the 2000s, we’ve started rounding out or dinosaurs a bit, and inferring speculative structures and behaviours from what we observe in the fossil record and in the world around us!
The details of integument including quills but also the foot scales and skin on the legs are inferred from the absolutely stunning Psitaccosaurus specimen from a few years ago, since it’s really the closest species we have to pachycephalosaurs that preserves those details.
I think a big part of the culture shift around palaeoart in the last few years is the acknowledgement that we as palaeoartists can never reconstruct a species 100% accurately, and that there is room for interpretation and speculation. If you’re guaranteed to be wrong anyway, you might as well experiment and try out new things, so long as it doesn’t contradict the things that are knowable!
And that’s brought us all the way through almost 120 years of Stegoceras validum, and also 120 years of cultural and artistic evolution in the way we look at and understand dinosaurs! Thanks for sticking with me, I hope you enjoyed the ride!
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#repost @ene.ribot ・・・ Jinfengopteryx elegans ⚡ . Hoy os comparto el principio de un trabajo de reconstrucción que estuve realizando, a finales del año pasado, con el curso de ilustra paleontología de @illustraciencia, con el crack ilustrador @metazoastudio como profesor. He tardado un poquillo en compartirlo pero aquí lo tenéis ✌️ . Ilustración 1: Skeletal de Jinfengopteryx elegans (Ji et al, 2005), un dinosaurio maniraptor y troodóntido del cretácico temprano (130-125 MA) de China. Ilustración 2: Estudio de su musculatura. Fotografía 3 y 4: holotipo de la especie, muy bien conservado, donde se pueden apreciar impresiones de sus plumas (Ji et al, 2005). . A partir de estos trabajos, y algunos más, realicé una ilustración final, espero que tengáis ganas de verla (?) 😌✨ . #paleoart #skeletal #musculature #troodontidae #dinosaur #jinfengopteryx #birdie #illustration #scientificillustration #drawing #draw #inspiration #ilustracióncientífica #digital #digitalart #art #artist #artwork #painting #illustration #sketch #artistsoninstagram #arte #photooftheday #like #instaart https://instagr.am/p/CKrwt0vgR6K/
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Tamarro insperatus Sellés et al., 2021 (new genus and species)
(Type metatarsal of Tamarro insperatus, from Sellés et al., 2021)
Meaning of name: Tamarro = small fantastic creature from Pallars folklore; insperatus = unexpected
Age: Late Cretaceous (Maastrichtian)
Where found: Talarn Formation, Lleida, Spain
How much is known: A partial second metatarsal (long bone of the foot).
Notes: Tamarro was a small theropod, probably a troodontid. Although small for a theropod, it was mid-sized by troodontid standards, being larger than its possible close relatives Jinfengopteryx and Philovenator. Based on microscopic examination of its internal bone structure, Tamarro grew faster than most other troodontids, nearing its adult size by the time it was a year old.
Reference: Sellés, A.G., B. Vila, S.L. Brusatte, P.J. Currie, and À. Galobart. 2021. A fast-growing basal troodontid (Dinosauria: Theropoda) from the latest Cretaceous of Europe. Scientific Reports 11: 4855. doi: 10.1038/s41598-021-83745-5
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Day 15: Mei long
A little basal sinovenatorinae of the Cretaceous Troodontid is dancing off in the Yixian forest floor.
Did dromaeosauridae and troodontidae have parental care?
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By Ripley Cook
Etymology: Named for Mahakala, one of the eight protector deities of Tibetan Buddhism
First Described By: Turner et al., 2007
Classification: Dinosauromorpha, Dinosauriformes, Dracohors, Dinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoromorpha, Maniraptoriformes, Maniraptora, Pennaraptora, Paraves, Eumaniraptora, Dromaeosauridae, Halszkaraptorinae
Time and Place: 80 million years ago, in the Campanian of the Late Cretaceous
Mahakala is known from the Tögrögiin Shiree of the Djadokhta Formation in Ömnögovi, Mongolia
Physical Description: Mahakala was a small raptor, about 70 centimeters in length, and it was very similar to the earliest members of the Eumaniraptoran group in general, sharing characteristics with other Eumaniraptorans like Troodontids and Avialans. Mahakala was also a Halszkaraptorine, a group of weird little raptors with a semiaquatic lifestyle. It is uncertain if Mahakala was semiaquatic, but it seems at least possible at this time. Like other raptors, it had a sickle claw on its second toe, and like Troodontids and Avialans, it had an extended third foot bone. It also had very short forelimbs compared to other raptors, but similar in size to those of Halszkaraptor. In Halszkaraptor, the forelimbs are adapted to form flippers, like that of a cormorant. While the wings of Mahakala aren’t quite to that extent, it’s possible that it was a transitional form, or had partly aquatically adapted forelimbs. As a raptor, Mahakala would have been covered in feathers, with wings on its arms and a tail fan on its tail.
By Ashley Patch
Diet: If Mahakala was like its close relative Halszkaraptor and associated with the water found in its environment, it would have most likely been a piscivore.
Behavior: Mahakala probably spent most of its time in or near sources of water, which were a tad hard to come by in its very arid environment. As such, it probably didn’t move about much, but spent its time at the oases and temporary rivers to find food in the water. It probably also swam about in the water, using its wings and legs to help propel it forward. It would have been a secretive sort of animal, being surrounded by many kinds of predators and threats, and wouldn’t have strayed far from its home. Given its rarity, and the uncommon nature of its probable preferred habitat, Mahakala would have probably not lived in social groups. However, it most likely took care of its young in some form.
Ecosystem: The Djadochta Formation was an arid desert environment, with red sand and dirt for miles and very little water for Mahakala to associate with. That being said, there were a decent number of oases in the environment, and temporary rivers called arroyos that would pop up during the wet season. Thus, Mahakala would have been mostly associated with the oases. Because of the red coloration of the ground (giving this area today the name of the Flaming Cliffs), most of the animals in the area would have actually been quite red or reddish, in order to blend in. In the oasis areas where Mahakala would have been found, there were probably horsetails and other water plants, rather than the dry shrubs and arid foliage found elsewhere in the environment. The Tögrögiin environment was not as diverse as the later Ukhaa Tolgod, but was still filled with a variety of animals. Here there were mammals such as Zalambdalestes, Kryptobaatar, and Barunlestes; lizards like Cherminotus, Adamisaurus, Temujinia, Zapsosaurus, Mimeosaurus, Flaviagama, Gurvansaurus, Dzhadochtosaurus, and Isodontosaurus; and other small animals. As for other dinosaurs, there was the Ankylosaur Pinacosaurus, the ceratopsian Protoceratops, the alvarezsaur Parvicursor (and possibly Shuvuuia), the ornithomimosaur Aepyornithomimus, and the raptor Velociraptor. In short, this was an exceptionally fluffy land indeed!
By Scott Reid
Other: It is interesting to note that Mahakala and Halszkaraptor not only are shown as closely related in phylogenetic analyses since the latter was described, but that Mahakala actually comes from the same, but earlier environment, as Halszkaraptor. It is entirely possible, therefore, that Mahakala is actually the ancestor of Halszkaraptor, with other members of this weird raptor group splitting off at around the same time as Mahakala began that transition. This is not directly found in studies yet, however, so take that hypothesis with a grain of salt. Regardless, Mahakala was a very basal raptor, and even though it lived late in the fossil record in the group - at a time when many later-derived forms were very common - it still had many similarities to the Troodontids and the Avialans in addition to the raptors.
~ By Meig Dickson
Sources under the Cut
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Chinzorig Tsogtbaatar; Yoshitsugu Kobayashi; Tsogtbaatar Khishigjav; Philip J. Currie; Mahito Watabe; Barsbold Rinchen (2017). “First Ornithomimid (Theropoda, Ornithomimosauria) from the Upper Cretaceous Djadokhta Formation of Tögrögiin Shiree, Mongolia”. Scientific Reports. 7: Article number 5835.
Clarke, Julia A., Norell, Mark A. (2002). “The morphology and phylogenetic position of Apsaravis ukhaana from the Late Cretaceous of Mongolia”. American Museum Novitates, No. 3387, American Museum of Natural History, New York, NY.
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Gianechini, F. A., P. J. Makovicky, and S. Apesteguía. 2017. The cranial osteology of Buitreraptor gonzalezorum Makovicky, ApesteguÍa, and AgnolÍn, 2005 (Theropoda, Dromaeosauridae), from the Late Cretaceous of Patagonia, Argentina. Journal of Vertebrate Paleontology 27(1):e1255639:1-19
Godefroit, Pascal; Currie, Philip J.; Li, Hong; Shang, Chang Yong; Dong, Zhi-ming (2008). “A new species of Velociraptor (Dinosauria: Dromaeosauridae) from the Upper Cretaceous of northern China”. Journal of Vertebrate Paleontology. 28 (2): 432–438.
Hartman, S., M. Mortimer, W. R. Wahl, D. R. Lomax, J. Lippincott, D. M. Lovelace. 2019. A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight. PeerJ: e7247.
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Ksepka, Daniel T.; Norell, Mark A. (2004). “Ornithomimosauria cranial material from Ukhaa Tolgod (Omnogov, Mongolia)”. American Museum Novitates. 3448: 1–4.
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Longrich, N. R., P. J. Currie, and Z.-M. Dong. 2010. A new oviraptorid (Dinosauria: Theropoda) from the Upper Cretaceous of Bayan Mandahu, Inner Mongolia. Palaeontology 53(5):945-960
Montague, R. (2006). “Estimates of body size and geological time of origin for 612 dinosaur genera (Saurischia, Ornithischia)”. Florida Scientist. 69 (4): 243–257.
Nesbitt, S. J., J. A. Clarke, A. H. Turner and M. A. Norell. 2011. A small alvarezsaurid from the Eastern Gobi Desert offers insight into evolutionary patterns in the Alvarezsauroidea. Journal of Vertebrate Paleontology 31(1):144-153
Norell, Mark A.; Clark, James M.; Dashzeveg, Demberelyin; Barsbold, Rhinchen; Chiappe, Luis M.; Davidson, Amy R.; McKenna, Malcolm C.; Perle, Altangerel; Novacek, Michael J. (November 4, 1994). “A theropod dinosaur embryo and the affinities of the Flaming Cliffs dinosaur eggs”. Science. 266 (5186): 779–782.
Norell, M.A.; Clark, J.M.; Turner, A.H.; Makovicky, P.J.; Barsbold, R.; Rowe, T. (2006). “A new dromaeosaurid theropod from Ukhaa Tolgod (Omnogov, Mongolia)”. American Museum Novitates. 3545: 1–51.
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Pei, R., Q. Li, Q. Meng, K.-Q. Gao, and M. A. Norell. 2014. A New Specimen of Microraptor (Theropoda: Dromaeosauridae) from the Lower Cretaceous of Western Liaoning, China. American Museum Novitates 3821:1-28
Prieto-Marquez, A., M. Bolortsetseg, and J. R. Horner. 2012. A diminutive deinonychosaur (Dinosauria: Theropoda) from the Early Cretaceous of Oosh (Ovorkhangai, Mongolia). Alcheringa 36(1):117-136
Turner, A. H., D. Pol, J. A. Clarke, G. M. Erickson, and M. A. Norell. 2007. A basal dromaeosaurid and size evolution preceding avian flight. Science 317:1378-1381
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Varricchio, D.J.; Barta, D.E. (2015). “Revisiting Sabath’s "Larger Avian Eggs” from the Gobi Cretaceous". Acta Palaeontologica Polonica. 60 (1): 11–25.
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Williamson, T. E., and S. L. Brusatte. 2014. Small theropod teeth from the Late Cretaceous of the San Juan Basin, northwestern New Mexico and their implications for understanding latest Cretaceous dinosaur evolution. PLoS ONE 9(4):e93190:1-23
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Worldbuilding June 2019 Episode 3: Sapient Species
3. Who lives in your world?
Once upon a time, a strange group of apes began walking bipedally. Meanwhile, on the other side of the world, a group of paravians were pushing themselves towards increasingly elaborate social displays of skill and creativity, and wound up self-selecting for intelligence as a side effect.
Enter the Droman:
Classification: Maniraptora, Paraves, Troodontidae, Neotroodontidae, Dexteropterygidae, Sapiornithoides
The Droman (Ouranodromeus artifex) is a mid-sized, advanced troodontid that is noteworthy for possessing intelligence on par with humans. Having evolved from a volant ancestry, young dromans retain a limited flying ability that is lost when they mature as the arms shrink relative to the body and the primaries recede from the distal end of digit II.
The wide array of aerial adaptations that dromans posses, despite a recent evolution towards increased size and hand dexterity, have allowed them to invent self-powered flight augmentations. This was the most groundbreaking turning point in their culture. This allowed them to open trade and communication throughout all their peoples and it’s the reason why there really is no such thing as “remote” in their half of the world.
Dromans are hypersocial and nearly all aspects of their society revolves around one single ideal: showing off. They paint and decorate themselves obsessively, and reinvent their appearances constantly. Their society is obsessed with the arts, to the point that most other fields of study are considered boring (much to the chagrin of dromans in those fields). There’s a social expectation that your appearance should reflect on your personality, interests, and skills, and failure to do so is generally treated with disdain. In short, dromans are incredibly vain an flighty, and their attention easily caught by whatever is new and interesting. They tend to pick up new hobbies and interests constantly, and drop them just as quickly--it’s rare to meet a droman who would devote their entire life to one pursuit, and they tend to find it rather strange that humans are so prone to doing so!
I have a lot, lot more information on them (they’re basically the only part of this world I’ve put any thought into), but I’ll save the details for each specific day.
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The above picture was made after I had drawn this hideous attempt at lionking fanart below.
I felt really disappointed in myself for just how terrible the second felt to me, especially given how much I like drawing cats and how much I felt I had regressed in my ability to draw them. For that reason hat I decided I really needed to study big cat anatomy more, and learn better how to stylize them.
In the lion study pic, the lion to the upper left is the least stylized and intended to reflect traits I observed in photos and videos of real lions. While there is a very small amount of stylization (such as my art style for drawing thick fur), it is overall intended to be most "accurate" lion in this picture.
The lion to the upper right is the most stylized and least accurate. While I certainly exaggerated things and took many creative liberties, I tried to make sure those traits still expanded upon elements I observed in real lions. His design is also based on a character concept from an older project www.deviantart.com/troodontida…
Essentially the first lion represents learning the rules. The second lion represents intentionally breaking those rules once I learned them but in ways that expand upon what I learned.
The lioness at the bottom is sort of intermediate. She's not conservative in design as the upper left lion, but neither is she as stylized and cartoony as the second. I also experimented with misc minor details that weren't in either of the previous lions.
The little lion doodle to the lower left was just me trying to make a little summary of basic patterns/trends I noticed in coloration, especially the manes. It's suprising how often lion manes are portrayed as dull colored when in real life they can actually have rather stunning patterns and colorations. Also manes can be incredibly varied among individual lions (which makes for a lot of potential for individual variation without even needing to exaggerate) but there were "trends" and many tended to share a similar basic pattern.
Another thing not often portrayed are the cool looking markings on the eyebrows.
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An experimental comic thing based on a story concept I’ve always wanted to make, in some manner, of about a mother cat in a post-apocalyptic horror setting. I haven’t really done backgrounds in ages and still trying to figure out stuff, so that’s why there’s so much inconsistency with them.
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dinos. My favorites.
Genus and Species:
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Art by masterhelbram on tumblr, but the Pokemon’s design is mine.
This is Tre Huka, a fakemon based on probably my favourite dinosaur, a Troodon!
And I know you said tha it doesn’t need Pokedex entry, but as it’s a fakemon that’s being used in a fanregion, it has all of that information already made
Monster and Flying egg groups
Ability: Strong Jaw
“Believed to be a common ancestor of the Treecko family, this Pokemon was thought to have travelled in packs when it roamed the world about 75 million years ago. Extremely social by nature, Tre Huka will often become depressed and withdrawn in isolation.”
“Omnivorous by nature, this Pokemon’s serrated teeth are used to tear into the flesh of prey. However, this Pokemon prefers to eat soft meat and plants.”
The reason for this Pokemon’s typing is that instead of being revived as a fossil, and so getting a rock typing, it instead gets revived from remains that were found in permafrost, hence it’s original grass/flying typing became ice/flying
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Large Dinosaurs Were Prone to Extinction Way Before The Asteroid, New Study Argues
After ruling the planet for more than 170 million years, non-avian dinosaurs were suddenly demoted from existence by the impact of a large asteroid that struck the Yucatán peninsula some 66 million years ago.
The collision set off a cascade of environmental devastation, with debris in the atmosphere cutting off life-giving sunlight. Earth’s surface temperatures plunged. Animals perished.
Well, that’s what most paleontologists think happened.
While evidence for this end-Cretaceous impact is indisputable, debate within the paleontological community has been ongoing as to whether dinosaur extinction was abrupt or gradual.
The extinctions do coincide with a period of long-term environmental upheaval, largely the result of the continued breaking up of the supercontinents Laurasia and Gondwana. High sea levels, cooling climates, the spread of new habitat on land, as well as massive volcanic activity, may have all played significant roles in the mass extinction event.
Up until now, analysis of fossil data has yielded no convincing evidence of a decline in dinosaur species before their extinction. A phylogenetic study in 2016, which used dinosaur timetrees, challenged the idea of a sudden extinction, but this conclusion proved to be contentious.
The fossil record is a notoriously difficult source of evidence, with critiques of that study pointing to gaps in the dinosaur fossil record and sampling biases which could have led to the under-reporting of certain Cretaceous dinosaur species.
Now, a new study has lent additional evidence to the hypothesis that non-avian dinosaurs were already teetering on the edge of extinction before the cataclysmic events of the infamous asteroid impact.
Led by French National Center for Scientific Research phylogeneticist Fabien Condamine, the authors of the new study claim that methodological developments in data analysis have allowed them to take into account certain biases in fossil data, along with uncertainties around the ages of fossils.
The team analysed 1,600 dinosaur fossils to assess the speciation and extinction rates of six major dinosaur families: Ankylosauridae, Ceratopsidae, Hadrosauridae, Dromaeosauridae, Troodontidae, and Tyrannosauridae.
The team found that the diversity of non-avian dinosaurs started to decline approximately 76 million years ago – that’s 10 million years prior to the Yucatán impact. They suggest the decline is linked to increased extinction rates in older species, who may have lacked evolutionary novelty and were unable to adapt to changing environmental conditions.
“These results imply that warm periods favored dinosaur diversification whereas cooler periods led to enhanced extinctions,” state the authors.
Ecological and physical factors point to a cooling climate as a catalyst for the decline of dinosaur species in the late Cretaceous. These cooling temperatures likely spelled trouble for large dinosaurs in particular, since they relied on a warm climate to maintain a stable body temperature.
“A physiological explanation for the cooling-driven extinction could be the hypothesis that if sex determination in dinosaurs was temperature dependent, as in crocodiles and turtles, sex switching of embryos could have contributed to diversity loss with a cooling global climate at the end of the Cretaceous,” the team added.
The researchers also point to additional factors, such as hadrosaurs outcompeting other herbivores – their teeth show they were able to eat a greater variety of plants than more specialized competitors. With herbivores playing an interconnected role in the food web, their decline may have been detrimental to a number of additional dinosaur species.
In the end, data from the new study suggest that the final extinction of dinosaurs really could not be solely attributed to a massive asteroid impact.
While the study could not point directly to the precise ecological mechanisms which underlay the effects of global cooling on dinosaur speciation and extinction rates, the results support the idea that long-term environmental changes likely made non-avian dinosaurs prone to extinction, even before a giant space rock smashed up their home planet.
The study was published in Nature Communications.