Illustration of Borealopelta markmitchelli dinosaur by Julius Csotonyi. Credit: © Royal Tyrrell Museum of Palaeontology
More than 110 million years back, a lumbering 1,300-kg (~2900 pounds), armor-plated dinosaur consumed its last meal, passed away, and was rinsed to sea in what is now northern Alberta. This ancient monster then sank onto its tough back, churning up mud in the seabed that entombed it — up until its fossilized body was found in a mine near Fort McMurray in 2011.
Since then, scientists at the Royal Tyrrell Museum of Palaeontology in Drumheller, Alta., Brandon University, and the University of Saskatchewan (USask) have actually been working to open the incredibly unspoiled nodosaur’s numerous tricks — including what this big armored dinosaur (a kind of ankylosaur) really consumed for its last meal.
“The finding of the actual preserved stomach contents from a dinosaur is extraordinarily rare, and this stomach recovered from the mummified nodosaur by the museum team is by far the best-preserved dinosaur stomach ever found to date,” stated USask geologist Jim Basinger, a member of the group that evaluated the dinosaur’s stomach contents, an unique mass about the size of a soccer ball.
“When people see this stunning fossil and are told that we know what its last meal was because its stomach was so well preserved inside the skeleton, it will almost bring the beast back to life for them, providing a glimpse of how the animal actually carried out its daily activities, where it lived, and what its preferred food was.”
There has actually been great deals of speculation about what dinosaurs consumed, however really unknown. In a just-published short article in Royal Society Open Science, the group led by Royal Tyrrell Museum paleontologist Caleb Brown and Brandon University biologist David Greenwood offers in-depth and conclusive proof of the diet plan of big, plant-eating dinosaurs — something that has actually not been understood conclusively for any herbivorous dinosaur previously.
“This new study changes what we know about the diet of large herbivorous dinosaurs,” stated Brown. “Our findings are also remarkable for what they can tell us about the animal’s interaction with its environment, details we don’t usually get just from the dinosaur skeleton.”
Previous research studies had actually revealed proof of seeds and branches in the gut however these research studies used no info regarding the sort of plants that had actually been consumed. While tooth and jaw shape, plant accessibility and digestibility have actually sustained substantial speculation, the particular plants herbivorous dinosaurs taken in has actually been mostly a secret.
So what was the last meal of Borealopelta markmitchelli (which suggests “northern shield” and acknowledges Mark Mitchell, the museum service technician who invested more than 5 years thoroughly exposing the skin and bones of the dinosaur from the fossilized marine rock)?
“The last meal of our dinosaur was mostly fern leaves — 88 percent chewed leaf material and seven percent stems and twigs,” stated Greenwood, who is likewise a USask accessory teacher.
“When we examined thin sections of the stomach contents under a microscope, we were shocked to see beautifully preserved and concentrated plant material. In marine rocks we almost never see such superb preservation of leaves, including the microscopic, spore-producing sporangia of ferns.”
Team members Basinger, Greenwood and Brandon University college student Jessica Kalyniuk compared the stomach contents with food plants understood to be readily available from the research study of fossil leaves from the very same duration in the area. They discovered that the dinosaur was a particular eater, picking to consume specific ferns (leptosporangiate, the biggest group of ferns today) over others, and not consuming numerous cycad and conifer leaves typical to the Early Cretaceous landscape.
Specifically, the group determined 48 palynomorphs (microfossils like pollen and spores) consisting of moss or liverwort, 26 clubmosses and ferns, 13 gymnosperms (mainly conifers), and 2 angiosperms (blooming plants).
“Also, there is considerable charcoal in the stomach from burnt plant fragments, indicating that the animal was browsing in a recently burned area and was taking advantage of a recent fire and the flush of ferns that frequently emerges on a burned landscape,” stated Greenwood.
“This adaptation to a fire ecology is new information. Like large herbivores alive today such as moose and deer, and elephants in Africa, these nodosaurs by their feeding would have shaped the vegetation on the landscape, possibly maintaining more open areas by their grazing.”
The group likewise discovered gastroliths, or gizzard stones, usually swallowed by animals such as herbivorous dinosaurs and today’s birds such as geese to help food digestion.
“We also know that based on how well-preserved both the plant fragments and animal itself are, the animal’s death and burial must have followed shortly after the last meal,” stated Brown. “Plants give us a much better idea of season than animals, and they indicate that the last meal and the animal’s death and burial all happened in the late spring to mid-summer.”
“Taken together, these findings enable us to make inferences about the ecology of the animal, including how selective it was in choosing which plants to eat and how it may have exploited forest fire regrowth. It will also assist in understanding of dinosaur digestion and physiology.”
Borealopelta markmitchelli, found throughout mining operations at the Suncor Millennium open pit mine north of Fort McMurray, has actually been on display screen at the Royal Tyrrell Museum considering that 2017. The primary piece of the stomach mass is on display screen with the skeleton.
Other members of the group consist of museum researchers Donald Henderson and Dennis Braman, and Brandon University research study partner and USask alumna Cathy Greenwood.
Research continues Borealopelta markmitchelli — the very best fossil of a nodosaur ever discovered — for more information about its environment and behaviour while it lived. Student Kalyniuk is presently broadening her deal with fossil plants of this age to much better comprehend the structure of the forests in which it lived. Many of the fossils she will analyze remain in Basinger’ collections at USask.
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Reference: “Dietary palaeoecology of an Early Cretaceous armoured dinosaur (Ornithischia; Nodosauridae) based on floral analysis of stomach contents” by Caleb M. Brown, David R. Greenwood, Jessica E. Kalyniuk, Dennis R. Braman, Donald M. Henderson, Cathy L. Greenwood and James F. Basinger, 3 June 2020, Royal Society Open Science.
DOI: 10.1098/rsos.200305
The research study was moneyed by Canada Foundation for Innovation, Research Manitoba, Natural Sciences and Engineering Research Council of Canada, National Geographic Society, Royal Tyrrell Museum Cooperating Society, and Suncor Canada, along with in-kind assistance from Olympus Canada.
