Hadrosaurs
Posted on 08/08/2018 12:28:30 PM PDT by ETL
Paleontologists have discovered the first North American co-occurrence of hadrosaur and therizinosaur tracks, providing more evidence that Alaska was the ‘superhighway’ for dinosaurs between Asia and western North America 65-70 million years ago (Late Cretaceous epoch).
In 2012-2014, Dr. Anthony Fiorillo from the Perot Museum of Nature and Science and colleagues discovered distinct footprints in Denali National Park, central Alaska Range, that they determined to be made by therizinosaurs, unusual predatory dinosaurs thought to have become herbivores.
What surprised the team most was the co-occurrence of dozens of hadrosaurs, also known as duck-bill dinosaurs.
“Hadrosaurs are very common and found all over Denali National Park. Previously, they had not been found alongside therizinosaurs in the park,” Dr. Fiorillo said.
“In Mongolia, where therizinosaurs are best known — though no footprints have been found in association — skeletons of hadrosaurs and therizinosaurs have been found to co-occur from a single rock unit so this was a highly unusual find in Alaska, and it prompted my interest.”
“From our research, we’ve determined that this track association of therizinosaurs and hadrosaurs is currently the only one of its kind in North America.”
The plant-eating therizinosaurs, which are rare and unusual creatures in the fossil record, had long skinny necks, little teeth, a small beak for cropping plants, and big torsos accompanied by large hind feet and long arms. ..."
Dr. Fiorillo has long postulated that Cretaceous Alaska could have been the thoroughfare for fauna between Western North America and Asia — two continents that shared each other’s fauna and flora in the latest stages of the Cretaceous.
“This study helps support the idea that Alaska was the gateway for dinosaurs as they migrated between Asia and North America,” said co-author Dr. Yoshitsugu Kobayashi, of Hokkaido University Museum in Japan.
(Excerpt) Read more at sci-news.com ...
Scientific Reports
volume 8, Article number: 11706 (2018)
We report details of a unique association of hadrosaur and therizinosaur tracks found in the Late Cretaceous lower Cantwell Formation, Denali National Park, central Alaska Range, Alaska.
This rock unit is now well-documented as a source of thousands of fossil footprints of vertebrates such as fishes, pterosaurs, and avialan and non-avialan dinosaurs.
The lower Cantwell Formation in this area consists of numerous fining-upward successions of conglomerates and pebbly sandstones, cross-stratified and massive sandstones, interbedded sandstones and siltstones, organic-rich siltstones and shales, and rare, thin, bentonites, typically bounded by thin coal seams, and it contains a diverse fossil flora.
We report the first North American co-occurrence of tracks attributable to hadrosaurs and therizinosaurs in the lower Cantwell Formation.
Although previously un-reported in North America, this association of hadrosaur and therizinosaur tracks is more characteristic of the correlative Nemegt Formation in central Asia, perhaps suggesting that parameters defining the continental ecosystem of central Asia were also present in this part of Alaska during the Latest Cretaceous. ...”
Entire paper here:
https://www.nature.com/articles/s41598-018-30110-8
I think the main take-away here is that they did it without taxpayer dollars!
(Now, I’m going back to read the article.) :)
4000ish years ago.
“A superhighway? I invented that!” - Al Gore
Reminds me of the 1960-70s game "Twister"...
Alaska Ping.
"Yeah, there it was, this huge, empty and
bare track of land, just sitting out there in
the middle of what was to become Alaska..." ...
And no doubt they were cruising in the left lane at 10 MPH below the posted speed limit, with their right turn signals blinking nonstop...
Sarah Palin can see Dinosaurs from her house? ;)
She did run with John McCain, so yes :)
Thanks ETL.
“Build the wall!” the therizinosaurs trilled, “Build the dang wall!” But they had no opposable thumbs and so could not build the wall. And just where are they now? Extinct, that’s where.
No spear points were found
Thorazinosaurus was really crazy before it started taking its meds.
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