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Western Canadian scientists discover what an armoured dinosaur ate for its last meal – EurekAlert

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IMAGE: Illustration of Borealopelta markmitchelli dinosaur by Julius Csotonyi
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Credit: © Royal Tyrrell Museum of Palaeontology

More than 110 million years ago, a lumbering 1,300-kilogram, armour-plated dinosaur ate its last meal, died, and was washed out to sea in what is now northern Alberta. This ancient beast then sank onto its thorny back, churning up mud in the seabed that entombed it–until its fossilized body was discovered in a mine near Fort McMurray in 2011.

Since then, researchers at the Royal Tyrrell Museum of Palaeontology in Drumheller, Alta., Brandon University, and the University of Saskatchewan (USask) have been working to unlock the extremely well-preserved nodosaur’s many secrets–including what this large armoured dinosaur (a type of ankylosaur) actually ate 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,” said USask geologist Jim Basinger, a member of the team that analyzed the dinosaur’s stomach contents, a distinct 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 been lots of speculation about what dinosaurs ate, but very little known. In a just-published article in Royal Society Open Science, the team led by Royal Tyrrell Museum palaeontologist Caleb Brown and Brandon University biologist David Greenwood provides detailed and definitive evidence of the diet of large, plant-eating dinosaurs–something that has not been known conclusively for any herbivorous dinosaur until now.

“This new study changes what we know about the diet of large herbivorous dinosaurs,” said 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 studies had shown evidence of seeds and twigs in the gut but these studies offered no information as to the kinds of plants that had been eaten. While tooth and jaw shape, plant availability and digestibility have fuelled considerable speculation, the specific plants herbivorous dinosaurs consumed has been largely a mystery.

So what was the last meal of Borealopelta markmitchelli (which means “northern shield” and recognizes Mark Mitchell, the museum technician who spent more than five years carefully exposing the skin and bones of the dinosaur from the fossilized marine rock)?

“The last meal of our dinosaur was mostly fern leaves–88 per cent chewed leaf material and seven per cent stems and twigs,” said Greenwood, who is also a USask adjunct professor.

“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 graduate student Jessica Kalyniuk compared the stomach contents with food plants known to be available from the study of fossil leaves from the same period in the region. They found that the dinosaur was a picky eater, choosing to eat particular ferns (leptosporangiate, the largest group of ferns today) over others, and not eating many cycad and conifer leaves common to the Early Cretaceous landscape.

Specifically, the team identified 48 palynomorphs (microfossils like pollen and spores) including moss or liverwort, 26 clubmosses and ferns, 13 gymnosperms (mostly conifers), and two angiosperms (flowering 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,” said 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 team also found gastroliths, or gizzard stones, generally swallowed by animals such as herbivorous dinosaurs and today’s birds such as geese to aid 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,” said 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, discovered during mining operations at the Suncor Millennium open pit mine north of Fort McMurray, has been on display at the Royal Tyrrell Museum since 2017. The main chunk of the stomach mass is on display with the skeleton.

Other members of the team include museum scientists Donald Henderson and Dennis Braman, and Brandon University research associate and USask alumna Cathy Greenwood.

Research continues on Borealopelta markmitchelli–the best fossil of a nodosaur ever found–to learn more about its environment and behaviour while it was alive. Student Kalyniuk is currently expanding her work on fossil plants of this age to better understand the composition of the forests in which it lived. Many of the fossils she will examine are in Basinger’ collections at USask.

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The research was funded 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, as well as in-kind support from Olympus Canada.

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New Class of Radio-Astronomical Objects Discovered: Odd Radio Circles | Astronomy – Sci-News.com

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An international team of astronomers has discovered an unexpected new class of radio-astronomical objects, consisting of a circular disk, which in some cases is limb-brightened, and sometimes contains a galaxy at its center. Named ‘Odd Radio Circles,’ these objects do not seem to correspond to any known type of astronomical object.

ASKAP radio continuum image of ORC 1 (contours) overlaid onto a DES 3-color composite image. Two galaxies of interest: ‘C’ lies near the center of ORC 1 and ‘S’ coincides with the southern radio peak. Image credit: Norris et al, arXiv: 2006.14805.

Circular features are well-known in radio-astronomical images, and usually represent a spherical object such as a supernova remnant, a planetary nebula, a shell around a star, or a face-on disk such as a protoplanetary disk or a star-forming galaxy.

They may also arise from imaging artifacts around bright astronomical objects.

Western Sydney University and CSIRO astronomer Ray Norris and his colleagues report the discovery of a class of circular feature in radio images that do not seem to correspond to any of these known types of object or artifact, but rather appear to be a new class of astronomical object.

“For brevity, and lacking an explanation for their origins, we dub these objects Odd Radio Circles (ORCs),” they said.

The researchers spotted three ORCs — named ORCs 1, 2 and 3 — in images from the Pilot Survey of the Evolutionary Map of the Universe, which is an all-sky continuum survey using the Australian Square Kilometre Array Pathfinder telescope (ASKAP).

A further radio source, called ORC 4, was discovered in archival observations of the galaxy cluster Abell 2142 taken with the Giant MetreWave Radio Telescope (GMRT).

All four ORCs are similar in displaying a strong circular symmetry and none of them have obvious counterparts in optical, infrared and X-ray wavelengths.

They differ in that two of them have a central galaxy while two do not, and three of them (ORCs 1, 2 and 4) consist of a partly filled ring while one (ORC 3) seems to be a uniform disk. There is also the puzzling fact that two of them are very close together, implying that these two ORCs have a common cause.

If the central galaxy in ORC 4 is associated with the ring, then the ring is 4.2 billion light-years away and has a size of 1.1 by 0.9 million light-years.

ASKAP radio continuum images of ORCs 2 and 3 from the Pilot Survey of the Evolutionary Map of the Universe and of ORC 4 from GMRT archival data. On the left are gray-scale images, with the synthesized beam shown in the bottom left corner, and radio contours overlaid onto DES optical images on the right. Image credit: Norris et al, arXiv: 2006.14805.

ASKAP radio continuum images of ORCs 2 and 3 from the Pilot Survey of the Evolutionary Map of the Universe and of ORC 4 from GMRT archival data. On the left are gray-scale images, with the synthesized beam shown in the bottom left corner, and radio contours overlaid onto DES optical images on the right. Image credit: Norris et al, arXiv: 2006.14805.

“We consider it likely that the ORCs represent a new type of object found in radio-astronomical images,” the scientists said.

“The edge-brightening in some ORCs suggests that this circular image may represent a spherical object, which in turn suggests a spherical wave from some transient event.”

“Several such classes of transient events, capable of producing a spherical shock wave, have recently been discovered, such as fast radio bursts, gamma-ray bursts, and neutron star mergers. However, because of the large angular size of the ORCs, any such transients would have taken place in the distant past.”

“It is also possible that the ORCs represent a new category of a known phenomenon, such as the jets of a radio galaxy or blazar when seen end-on, down the ‘barrel’ of the jet.”

“Alternatively, they may represent some remnant of a previous outflow from a radio galaxy.”

“However, no existing observations of this phenomenon closely resemble the ORCs in features such as the edge-brightening or the absence of a visual blazar or radio galaxy at the center.”

“We also acknowledge the possibility that the ORCs may represent more than one phenomenon,” they added.

“Further work is continuing to investigate the nature of these objects.”

The astronomers submitted their paper for publication in the journal Nature Astronomy.

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Ray P. Norris et al. 2020. Unexpected Circular Radio Objects at High Galactic Latitude. Nature Astronomy, submitted for publication; arXiv: 2006.14805

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UAE's Mars orbiter launch from Japan delayed by weather – ThePeterboroughExaminer.com

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TOKYO – The liftoff of the United Arab Emirates’ Mars orbiter was postponed until Friday due to bad weather at the Japanese launch site.

The orbiter named Amal, or Hope, is the Arab world’s first interplanetary mission. The launch was scheduled for Wednesday from the Tanegashima Space Center in southern Japan, but the UAE mission team announced the rescheduled date on Twitter.

Mitsubishi Heavy Industries’ H-IIA rocket will carry UAE’s craft into space. Mitsubishi launch official Keiji Suzuki had said on Monday a postponement was possible as intermittent lightning and rain were forecast over the next few days.

Heavy rain has fallen for more than a week in large areas of Japan, triggering mudslides and floods and killing more than 70 people, most of them on the southern main island of Kyushu.

Hope is set to reach Mars in February 2021, the year the UAE celebrates 50 years since its formation. A successful Hope mission would be a major step for the oil-dependent economy seeking a future in space.

Hope carries three instruments to study the upper atmosphere and monitor climate change and is scheduled to circle the red planet for at least two years.

Emirates Mars Mission Project Director Omran Sharaf, who joined Monday’s briefing from Dubai, said the mission will provide a complete view of the Martian atmosphere during different seasons for the first time.

Two other Mars missions are planned in coming days by the U.S. and China. Japan has its own Martian moon mission planned in 2024.

___

Follow Mari Yamaguchi on Twitter at https://www.twitter.com/mariyamaguchi

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UAE’s Mars orbiter launch from Japan delayed by weather – 570 News

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TOKYO — The liftoff of the United Arab Emirates’ Mars orbiter was postponed until Friday due to bad weather at the Japanese launch site.

The orbiter named Amal, or Hope, is the Arab world’s first interplanetary mission. The launch was scheduled for Wednesday from the Tanegashima Space Center in southern Japan, but the UAE mission team announced the rescheduled date on Twitter.

Mitsubishi Heavy Industries’ H-IIA rocket will carry UAE’s craft into space. Mitsubishi launch official Keiji Suzuki had said on Monday a postponement was possible as intermittent lightning and rain were forecast over the next few days.

Heavy rain has fallen for more than a week in large areas of Japan, triggering mudslides and floods and killing more than 70 people, most of them on the southern main island of Kyushu.

Hope is set to reach Mars in February 2021, the year the UAE celebrates 50 years since its formation. A successful Hope mission would be a major step for the oil-dependent economy seeking a future in space.

Hope carries three instruments to study the upper atmosphere and monitor climate change and is scheduled to circle the red planet for at least two years.

Emirates Mars Mission Project Director Omran Sharaf, who joined Monday’s briefing from Dubai, said the mission will provide a complete view of the Martian atmosphere during different seasons for the first time.

Two other Mars missions are planned in coming days by the U.S. and China. Japan has its own Martian moon mission planned in 2024.

___

Follow Mari Yamaguchi on Twitter at https://www.twitter.com/mariyamaguchi

Mari Yamaguchi, The Associated Press

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