#Maiasaura peeblesorum

[makairodonx]

Dinovember 2024 Day 20: The Good Mother - Maiasaura peeblesorum

[jaydexbg]

So giving them robo arms to hold their shit has been the best decision ever (info after imgs)

So im going absolutely feral about this AU, so in order to make sure they can still fight their war with guns i gave them robotic arms attached to the thingys on their armour.

Sim Troopers and regular soldiers have about what Church/Sarge wear, while Freelancers and special ops like Locus and Felix are closer to Tex. Hiding specific markings + making them more resilient.

Also please enjoy this height reference I've made (Locus gets honorary Red bc he deserves it). Some heights have been changed to be larger, in Lopez and Tex's case have been drastically changed as they are robots. Nerd stuff about who is what below.

Caboose [Ankylosaurus magniventris]

Church, Carolina, Tex [Utahraptor ostrommaysi]

Washington [Megalosaurus bucklandii]

Tucker [Allosaurus fragilis]

Doc [Kentrosaurus aethiopicus]

Donut [Deinonychus antirrhopus]

Grif, Kaikaina [Pachyrhinosaurus lakustai]

Simmons [Maiasaura peeblesorum]

Sarge [Daspletosaurus torosus]

Lopez [Nasutoceratops titusi]

Locus [Lythronax argestes]

Edit: I forgot Donut and Doc my sons I'm so sorry the bit has breached containment

[softenedsunbeams]

ASK AND YOU SHALL RECEIVE

okay why is maiasaura the bestest dinosaur. go

OKAY!! my best defense for maiasaura

1. it's the first dinosaur we found with evidence of actually mothering their young, which was huge at the time. skeletons found with eggs and young next to nests. its a big enough thing that their name literally means "mother lizard " they changed a lot in paleontology

ADDITIONALLY, baby maiasaura fossils show their legs were not fully developed at birth but they still have teeth worn which means their parents brought them food. instead of sitting on eggs they used the heat from rotting vegetation to warm them. and i think thats so so cool

2. they lived in HUGE herds with like 100 animals. they're kinda like cattle to me. big animal in big groups. anyways it would be so so cool to see those we usually dont associate dinosaurs with big groups like that i think

3. they're duck billed dinosaurs, which usually have crests, but they're bald..and it's silly looking.. and also they're really pretty.. in a weird ugly way..

^ ( looking ass...

4. i just think they're neat. yeah honestly thats it i just think they're neat

5. the only representative species has the name of maiasaura peeblesorum. which i think just says something on its own i dont need to elaborate. peeblesorum

[a-dinosaur-a-day]

Maiasaura peeblesorum

By José Carlos Cortés

Etymology: Good Mother Reptile

First Described By: Horner & Makela, 1979

Classification: Dinosauromorpha, Dinosauriformes, Dracohors, Dinosauria, Ornithischia, Genasauria, Neornithischia, Cerapoda, Ornithopoda, Iguanodontia, Dryomorpha, Ankylopollexia, Styracosterna, Hadrosauriformes, Hadrosauroidea, Hadrosauromorpha, Hadrosauridae, Euhadrosauria, Saurolophinae, Brachylophosaurini

Status: Extinct

Time and Place: Between 77.2 and 76.3 million years ago, in the Campanian of the Late Cretaceous 

Maiasaura is known from the Upper member of the Two Medicine Formation in Montana 

Physical Description: Maiasaura was a medium-sized hadrosaur - aka, a “duck-billed” dinosaur. Famed for being known from hundreds of individual skeletons, we have a general idea of the appearance of this dinosaur at every stage of its life cycle. Baby Maiasaura were around 0.4 meters in length and were positively tiny in weight, weighing less than 250 kilograms. These babies were adorable in appearance: with large eyes, small heads, and small limbs. The limbs were very weak and skinny at this point in life. Despite this extremely small size, Maiasaura young grew quickly - growing to 1.5 meters in length by the first year, and reaching sexual maturity at about the age of three or so, when they weighed around 1250 kilograms. Full skeletal maturity then came at about five years of age. At this point, Maiasaura were as much as 3000 kilograms in weight, and reaching 9 meters in length. Maiasaura adults were much beefier than the young - with thick, strong hind legs and somewhat more gracile front legs, it was almost as if they had deer front legs and elephant hind legs. The front feet formed hoof-like structures - with the pinky and thumb both sticking out, the middle three fingers were fused together. The hind limbs were typical ornithopod feet, with three toes splayed out like that of a very thick bird. Their tails were thick and muscular, and their torsos also very beefy. They had very thick, muscular necks as well.

By Ripley Cook

The heads of Maiasaura were rectangular and long, with flattened duck bills in the front. In the jaws, there were rows upon rows of densely packed teeth, forming a single surface. This surface was essentially serrated with the number of teeth packed in there. The upper jaws could then expand, allowing the lower jaws to slide upwards into them, creating a chewing motion. The more duck-like front bill was used to snip off plants and bring them into the jaw. Maiasaura also had a very large nose, forming a sort of lump in the front of the snout - this would have helped keep the head cool, and also allowed Maiasaura to make a variety of calls without a hollow crest attached. Above the eyes the skull of Maiasaura was domed with the brain area. In front of the eyes, on the top of the skull, there was a little ridged crest for display. It is logical to suppose that said crest would be somewhat patterned or even colorful, for display. 

By Nobu Tamura, CC BY 3.0

Scale impressions from Maiasaura are known. Adults of this species were entirely scaley, with almost a pebble-like texture of scales covering the entire body. These small round patches didn’t seem to overlap much, but were densely packed and not leaving much in the way of bare skin showing. Very small ones no longer than 2 millimeters were interspersed with bigger, more hexagonal ones at five to ten millimeters long. It is possible that fuzz would extend between the scales, but they would have looked rather like plants growing between sidewalk scales, and fairly impossible to see ultimately. The back was bumpy from the spine, and rather high over the animal - making Maiasaura itself quite tall. The scales were even bigger on this portion of the animal. Though skin impressions are known from Maiasaura adults and close relatives, baby Maiasaura do not have preserved skin impressions. What this means is that, while it seems very logical they’d also be scaly, there is a possibility they were fluffy to stay warm, given their smaller size. We present one hypothetical reconstruction of such for you all below, with the caveat that it is purely speculation at this time. 

By Diane Ramic

Diet: Maiasaura, like other hadrosaurs, fed mainly on soft, wet vegetation at low and middle levels of browsing (rather more tough, hard, dry vegetation like scrub plants and desert brush). So, it would favor leaves, berries, and more tender shoots, as well as plants in sources of water. 

By Madchester, in the Public Domain

Behavior: Maiasaura was a highly social, active animal - warm blooded in energy levels, these dinosaurs would have spent most of their time, each and every day, wandering around looking for food and socializing with other members of the herd. They spent a good portion of their time taking care of their young, of course, but that was only during the breeding season. Nests were made in large breeding colonies, not unlike their modern bird relatives such as seabirds, with gaps between nests only 7 meters long - less than the length of the adults that had to move between them! Between thirty and forty eggs were laid in a dense spiral pattern, and these eggs were the size of an ostrich’s today. Rotting vegetation was placed upon the nest to keep it warm. The babies, not able to take care of themselves upon hatching, entirely relied on their parents to bring them back chewed up food and look out for their safety. Sadly, most of the young would still die in the first year of life - mainly due to disease and predation, up to 90% of the young would die in the first year of life. Still, the parents did their best - with the young having features associated with cuteness, indicating dependence on the parents for survival until they reached larger sizes. 

By Debivort, CC BY-SA 3.0

Past that point, however, as the young grew faster, they fared better in terms of mortality - dropping down to 12% mortality until reaching old age again. They began to move on their own and keep up with the herd as it moved about. Young Maiasaura would walk on two legs, and as they got heavier they would switch to four, still sometimes only using the hind limbs when needed. Upon reaching sexual maturity at around three years of age, they began to get even bulkier. The Maiasaura would live in herds hundreds of individuals large, which would have been very noisy - using those bulky nostrils to make very loud, differing calls. Come mating time, they would display to each other with the ridges on their heads and other patterns. It is uncertain who was in charge of caring for the young, as sexual dimorphism isn’t seen in the skeletons of Maiasaura - if it was just the mother, both parents, just the father, or even the parents and previous children, we do not know at this time. The herd structure would protect the young, the sick, and the old from predators, and they would probably call to each other to ensure that they stayed safe in the face of predation. That being said, most of the rest of Maiasaura would then die in old age, with the death rate jumping up to 44% at the oldest ages of 12 to 14, when their own weight, slowness, and illness would leave them more vulnerable to predators. 

By Fabrizio De Rossi, retrieved from Earth Archives

Ecosystem: The Two Medicine Formation was one of the most iconic dinosaur ecosystems of all time, sort of a precursor in many ways to the more famous Hell Creek, but with more variety and dinosaur diversity! Here was a very large floodplain, filled with rivers and deltas and associated plantlife on sandy riverbanks. This environment was highly associated with the ever-present Western Interior Seaway, much like the later Hell Creek. It was seasonally arid, with rainshadows from the nearby Cordilleran Highlands, which may have been at least somewhat volcanic. This made the Two Medicine Environment positively volatile - with flash flooding, droughts, dehydration, and volcanic activity all allowing for the animals in this region to be wonderfully preserved (allowing us to know so much about Maiasaura)! Plants would grow very rapidly each wet season, making the area a very lush habitat for about half the year, allowing for all these dinosaurs to congregate here. This environment was filled with conifers and pine trees primarily, though there were also other types of plants as well. There were non-dinosaurs here as well - the pterosaurs Montanazhdarcho and Piksi, the Choristodere Champsosaurus, unnamed crocodylians, lizards like Magnuviator, mammals such as Cimexomys, Paracimexomys and Alphadon, and a wide variety of turtles like Basilemys. 

By Sam Stanton

Still, dinosaurs were the primary feature of the later (Upper) Two Medicine environment where Maiasaura frequented. There were four different types of Ceratopsians: the flat-nosed Achelosaurus, the curved-horned Einiosaurus, the giant-horned Rubeosaurus/Styracosaurus (depending on who you talk to, lumping-wise), and the small herbivore Prenoceratops. Ankylosaurs came in three different varieties - the large-spined but wiggle-taled Edmontonia, and the wide tail-clubbed Dyoplosaurus and Scolosaurus. Other hadrosaurs shared this environment with Maiasaura, like the large-nosed Gryposaurus, the round-crested Hypacrosaurus, and the small pointed crest having Prosaurolophus. There was also the small, active burrower Orodromeus. As for theropods, there were two different raptors - Bambiraptor and Richardoestesia - which would have been major problems for younger Maiasaura and the babies and eggs. The predatory opposite-bird, Gettyia, would have also been a predator of these smaller individauls. The troodontid Saurornitholestes would have been a major danger to these young Maiasaura along with its close cousins. The adults, on the other hand, had not one but two different species of tyrannosaur to contend with: the bulky and rarer Daspletosaurus, and the more slender Gorgosaurus that has been hypothesized to feed more on hadrosaurs than its cousin (though this is under hot debate). In short, this was the place to be to see just how diverse and fascinating non-avian dinosaurs were right at the end of their tenure, and Maiasaura was a major part (if not the most common part) of that ecosystem.

By Scott Reid

Other: Maiasaura is the closest thing non-avian dinosaurs get to a “model organism” - a creature with enough specimens, research, and data about it to use it as an example for other animals which we know less about. With hundreds of specimens found and counting, we have recorded a complete growth sequence of this dinosaur, knowing what the trajectory of a typical Maiasaura life was like. This is of vital importance, as hadrosaurs were some of the most diverse dinosaurs at the end of the Cretaceous - the end of the time of non-avian forms. It is also fascinating for how much the life history of Maiasaura - a dinosaur not close to being a bird by any stretch of the imagination - is so similar to birds. With similar rapid growth rates as their warm-blooded cousins, and similar nesting and group living strategies, Maiasaura showcases how complex behavior and lifestyles were common over the entirety of the dinosaur group. Maiasaura is also of fundamental importance because, with its discovery and descriptions in the late 1970s, it served with Deinonychus to show how dinosaurs weren’t slow, sluggish, giant lizards - but active, warm-blooded avian precursors. Dinosaurs were active, behaviorally complex, and took care of their young - something that was a truly revolutionary statement before these dinosaurs were named! So, despite not really looking like much, Maiasaura is probably one of the most important dinosaur discoveries ever found. Maiasaura itself is closely related to dinosaurs such as Brachylophosaurus, and is in general part of the “crestless” hadrosaur group, along with the contemporary Gryposaurus and the later Edmontosaurus.

~ By Meig Dickson

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Varricchio, D. J. 2001. Late Cretaceous oviraptorosaur (Theropoda) dinosaurs from Montana. pp. 42–57 in D. H. Tanke and K. Carpenter (eds.), Mesozoic Vertebrate Life. Indiana University Press, Indianapolis, Indiana.

Versluys, J. 1923. Der Schädel des Skelettes von Trachodon annectens im Senckenberg-Museum. Abhandlungen Der Senckenbergischen Naturforschenden Gesellschaft 38:1–19.

Weishampel, D. B., and J. B. Weishampel. 1983. Annotated localities of ornithopod dinosaurs: implications to Mesozoic paleobiogeography. The Mosasaur 1:43-87

Weishampel, D. B., and J. R. Horner. 1990. Hadrosauridae. In D. B. Weishampel, H. Osmolska, and P. Dodson (eds.), The Dinosauria. University of California Press, Berkeley 534-561

Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. 861 pp.

Woodward, H. N., E. A. Freedman Fowler, J. O. Farlow, J. R. Horner. 2015. Maiasaura, a model organism for extinct vertebrate population biology: a large sample statistical assessment of growth dynamics and survivorship. Paleobiology 41 (4): 503-527.

Woodward, H. N. (2019). Maiasaura (Dinosauria: Hadrosauridae) Tibia Osteohistology Reveals Non-Annual Cortical Vascular Rings in Young of the Year. Frontiers in Earth Science, 7, 50.

[thecoffeeisblack]

Montana, 76  million years ago. It's mid-morning and the sun has risen high into the sky, beams of radiant warmth wash over the nesting site of a herd of Maiasaura peeblesorum. 

While the older members of the group have been awake and moving about since dawn, a newborn wakes from a peaceful sleep to a nightmare, realizing too late that the shadow being cast from above does not belong to its that of its parents.

Jaws caked with the blood of sleeping and unhatched victims open to reveal a jagged dentition. The infant opens it's tiny mouth to scream in fear and horror.

When born, M. peeblesorum hatchlings were only about the size of a cat (16 inches) and were estimated to grow from that to larger than the size of a German Shepard (58 inches) in their first year. If they made it to adulthood they would be 30 feet long and weigh between 6 to 8 tons.

Small hatchlings would have encountered many dangers, including that of small theropods like Troodontids and Dromaeosaurs that lived in the region they inhabited. While better able to defend themselves as adults, it was likely that staying in a group was their best tactic being large  only meant you had to deal with larger predators back in the Late Cretaceous.

[harmalite]

Edmontosaurus is one of the few non-avian dinosaur genera for which we know almost the exact life appearance. This is thanks to several fantastically preserved skin casts - whatever the hell the Saurolophines were doing in life (and death) led them to be mummified 23 times more often than the next most common dinosaur mummy, the Nodosaurs. Thank you, Saurolophines!

Sources for features under the cut:

Premaxillary nail (LACM 23502) - “duckbill” beaks were much deeper than previously assumed, having a vertical overhang of keratin

Deep neck tissue (AMNH 5060) - folded skin impressions are found several inches above the cervical vertebrae. The edges of this tissue were accidentally destroyed in preparation but the contour between the neck and torso would probably be indistinct.

Soft dorsal frill above head and neck (Inferred, Edmontosaurus regalis, UALVP 53722) - This specimen only preserves a small lobe directly over the head but AMNH 5060 suggests it extended further in annectens

Dewlap (NMSG P 0001) - Skin impressions are found well below the mandible.

Large, vertically elongated scaly tubercules covering the neck (Inferred, Edmontosaurus regalis  UALVP 53722 , Maiasaura peeblesorum ROM 44770)

Hoofed manus (MRF-03 ”Dakota”) - The 3rd digit supports a large weight-bearing hoof and the smaller 2nd digit bears an elongate claw. The 4th and 5th digit are covered entirely in skin and the 1st digit (thumb) is absent. There were no birdlike tarsal scutes, small pavement scales extend all the way to the edge of the nail. The skin of the forearm is thick and horizontally furrowed.

Midline feature scales (MOR V007) - Several Edmontosaurus specimens display a row of rectangular scales or scutes,  around 45mm tall, above the dorsal midline

Deep tail tissue (MOR V007 & MRF-03 “Dakota) - The tail’s height was augmented almost 50% by superficial tissue and powerful muscle connections to the legs, indicating the animal was a fast runner.

Striped coloration (Speculative, MRF-03 “Dakota” & AMNH 5060) - Henry Osborn theorized that the clusters of feature scales clusters correlate to areas of darker pigment, and Dakota appears to have a faint stripey discoloration. I’m not totally sold on this since neither has been submitted (justifiably, since they’re priceless specimens) to molecular analysis and it doesn’t match color patterns in modern reptiles, but it makes for an interesting “king cheetah” sort of look

Dorsal spines (Speculative) - Floppy neck; iguana comparison is inevitable. The unfolded sections of the neck frill are thinner than the scale clusters supporting the MFS along the back so I figure the structures there would be different.

[comparativetarot]

The Empress. Art by Kmonvish Lawan, from Arcana Saurus.

Maiasaura peeblesorum

Now things start to get more symbolic, The carpet is the only thing from the classic version. I used Maiasaura to show a strong mother, from the meaning of the card, and her baby.

[remake-de-disney-dinosaurio]

Maiasaura, lagarto buena madre

Entremos en contexto: Maiasaura Peeblesorum es la única especie conocida del género extinto Maiasaura ("lagarto buena madre") de dinosaurio ornitópodo hadrosáurido, que vivió a finales del período Cretácico superior, hace aproximadamente entre 76,7 y 70,6 millones de años, en el Campaniense, en lo que es hoy Norteamérica. Junto a los restos descubiertos se encontraron decenas de nidos, en lo que hoy se llama Montaña de los Huevos, Egg´s Mountain, en Montana, Estados Unidos. Ésta fue la primera prueba de que los dinosaurios gigantes alimentaban a sus crías.

¿Iba a estar el Maiasaura en Disney Dinosaurio?

Originalmente iban a haber más especies en la manada de Kron, dentro de las cuales se incluye al Maiasaura. Este dinosaurio iba a tener tres artes conceptuales:

1° Parecido a una cebra, rayas negras en piel azul

2° Parecido a una gacela, cafe con manchas blancas

3° Parecido a un pato

Me agrada más el segundo diseño, ya que e ve muy natural. El primero y el tercero quedan mejor para especies nuevas dentro del remake

[ninelivesonelove]

Honestly like thank you for being so sweet

aw!! it’s no problem! i always try to be as nice as possible to anyone and everyone!

[sapphicseekingsapphic]

Maia, 21, NJ (soon to be WV) I’m an animal-loving nerd who would always like to meet more friends! I have a ton of interests and I love a lot of music, so I bet we could click over something! @maiasaura-peeblesorum

[tetrameryxx]

Maiasaura peeblesorum, this one was fun! 

[a-dinosaur-a-day]

@dianeramic drew this for me for her kickstarter and I keep forgetting to upload it because my life is a whirlwind of chaos 

I asked for some Maiasaura (as it is my favorite dinosaur) and some speculative fluffy Maiasaura babies! We know that adult Maiasaura were entirely scaley due to skin impressions but we know very little about the integument of their young. There really isn’t any scientific support for them being puffs, but since it’s not really something that’s been drawn much before, I figured it wouldn’t hurt to ask for it! It’ll be in the Maiasaura entry (but since it still has a lot of art I don’t have explicit permission to use, it’ll be a while before I throwback to it). 

Thanks again Diane! And be sure to check out her blog and her new coloring book coming out soon!

[dinodorks]

Skeleton of a young Maiasaura peeblesorum.

[thecoffeeisblack]

Color work in progress for a very surprised Maiasaura peeblesorum hatchling.

[dmmax]

Maiasaura Peeblesorum                                                       

If you steal it I will cry.