An artist’s conception shows a type of dicynodont known as Dicynodon. (Illustration by Marlene Hill Donnelly)
Dental exams conducted on fossils from more than 200 million years ago suggest that the earliest true tusks were sported by breeds of weird-looking creatures known as dicynodonts.
The evidence, laid out today in the Proceedings of the Royal Society B, could shed light on how species ranging from elephants and walruses to warthogs and rabbit-like hyraxes came to have tusks.
“Tusks have evolved a number of times, which makes you wonder how — and why?” study co-author Christian Sidor, a biology professor at the University of Washington and a curator at UW’s Burke Museum of Natural History and Culture, said in a news release. “We now have good data on the anatomical changes that needed to happen for dicynodonts to evolve tusks. For other groups, like warthogs or walruses, the jury is still out.”
The Burke Museum’s Kelsie Abrams works on the “Flyby Trike” dinosaur fossil in Montana. (Burke Museum Photo / Rachel Ormiston)
Theropods and Triceratops and hadrosaurs, oh my! Seattle’s Burke Museum of Natural History and Culture is making significant additions to its dinosaur holdings, thanks to a summer expedition to Montana’s Hell Creek Formation.
Four distinct dinosaurs were dug up, and all of the fossils will be brought back to the Burke Museum on the University of Washington’s campus, where the public can watch paleontologists remove the surrounding rock in the museum’s fossil prep lab.
“Each fossil that we collect helps us sharpen our views of the last dinosaur-dominated ecosystems and the first mammal-dominated ecosystems,” Gregory Wilson Mantilla, the Burke Museum’s curator of vertebrate paleontology and a biology professor at UW, said today in a news release. “With these, we can better understand the processes involved in the loss and origination of biodiversity and the fragility, collapse and assembly of ecosystems.”
An artist's conception shows the ancient human known as Dragon Man in his habitat. (Credit: Chuang Zhao via AAAS)
It’s time to add a new name to the list of ancient human species discovered in the fossil record — or is it?
The latest contender is a species dubbed Homo longi, created on the basis of a skull that was discovered in northern China in the 1930s, hidden for decades, and finally analyzed for a trio of researchpapers in The Innovation, an open-access journal published by Cell Press.
The almost perfectly preserved fossil is the largest skull ever found representing the genus that includes modern humans (Homo sapiens). Based on the skull’s morphology and geochemical dating techniques, researchers say it’s most likely to have come from a male who was about 50 years old when he died 146,000 years ago.
Researchers at Hebei GEO University have nicknamed the ancient individual “Dragon Man” in recognition of its Chinese origins. The species’ scientific name plays off the Chinese word for dragon (“long”) and the region around Harbin City where the fossil was found — Heilongjiang (“Black Dragon River”) province.
The skull could hold a brain comparable in size to ours, but had larger, almost square eye sockets, thick brow ridges, a wide mouth and oversized teeth. “While it shows typical archaic human features, the Harbin cranium presents a mosaic combination of primitive and derived characters setting itself apart from all the other previously named Homo species,” study author Qiang Ji, a paleontologist at Hebei GEO University, said in a news release.
Ji and his colleagues say the skull’s peculiarities justify its status as a species that’s distinct from Neanderthals and Denisovans and other extinct human ancestors. They even claim that Homo longi is more similar to humans of the Pleistocene era than those others.
“It is widely believed that the Neanderthal belongs to an extinct lineage that is the closest relative of our own species,” said study author Xijun Ni, a professor of primatology and paleoanthropology at the Chinese Academy of Sciences and Hebei GEO University. “However, our discovery suggests that the new lineage we identified that includes Homo longi is the actual sister group of H. sapiens.”
There’s some question about Dragon Man’s status, however.
Artwork shows the early primate species known as Purgatorius mckeeveri. (Andrey Atuchin Illustration via Burke Museum)
The shapes of fossilized teeth from 65.9 million-year-old, squirrel-like creatures suggest that the branch of the tree of life that gave rise to us humans and other primates flowered while dinosaurs still walked the earth. That’s the claim coming from a team of 10 researchers across the U.S., including biologists at Seattle’s Burke Museum and the University of Washington.
In a study published by Royal Society Open Science, the team lays out evidence that an ancient group of primates known as plesiadapiforms must have emerged before the mass-extinction event that killed off the dinosaurs. (Technically, modern-day birds are considered the descendants of dinosaurs, but that’s another story.)
The evidence comes from an analysis of tooth fossils that were unearthed in the Hell Creek area of northeastern Montana.
Geophysicists Walter Alvarez (at left) and Mark Richards (in the background) examine a piece of impact ejecta at the North Dakota fossil site. (Jackson Leibach Photo via University of Kansas)
After days of puzzling over secondhand reports, anyone with an internet connection can now read a research paper about a fossil graveyard in North Dakota that appears to document the day nearly 66 million years ago when an asteroid pushed the dinosaurs and many other species into extinction.
“I am very much looking forward to the crowd-sourced opinions of everyone,” University of Edinburgh paleontologist Steve Brusatte said in a tweet. “There is a real thrill and a real mystery around this discovery, and it is EXCITING! Let’s see where the evidence leads.”
The study documents fossil evidence for a catastrophic fish kill that did in many other organisms as well. Intermixed with the fossilized remains were tiny beads of glass that had turned to clay. Some of those beads were found embedded in the gills of the fish.
The evidence led the research team, headed by paleontologist Robert DePalma, to conclude that the Cretaceous creatures were washed up onto a sandbar by a giant wave of water. Then they were pelted by hot droplets of molten rock, known as tektites, which were thrown up into the stratosphere by an asteroid impact thousands of miles away.
In the paper, the research team lays out a scenario suggesting that the impact produced a magnitude 10 to 11 earthquake, which sparked a standing wave in the body of water where the fish had lived. Such a wave, known more scientifically as a seiche (pronounced like “saysh”), could have done as much damage as a tsunami within an hour after the asteroid hit. That scenario would leave enough time for the tektites to deliver the coup de grace.
One of the study authors who came up with that scenario is Mark Richards, a geophysicist who left the University of California at Berkeley last July to become the University of Washington’s provost and executive vice president for academic affairs.
Today, Richards said the seiche scenario isn’t the only possibility for explaining what happened in North Dakota during what’s known as the Cretaceous-Paleogene or Cretaceous-Tertiary extinction.
“I think that the surge, unless it was some freak coincidence with something else, was likely seismically induced,” Richards told GeekWire. “Now, it could have been from a seiche. Also, for example, you could have had a local landslide that was triggered by seismic waves. We have to be pretty cautious.”
Tyrannosaurus rex may have reigned as “king of the tyrant lizards” 65 million years ago, but 185 million years before that, a reptile about the size of an iguana was the king of Antarctica.
At least that’s the message contained in the name of a fossil that’s described in a newly published research paper — and is now part of the permanent collection at Seattle’s Burke Museum of Natural History and Culture.
The fossil was collected during an expedition to the frozen continent led by Christian Sidor, who is the museum’s curator of vertebrate paleontology as well as a biology professor at the University of Washington. Sidor and two colleagues, the University of the Witwatersrand’s Roger Smith and Brandon Peecook of Chicago’s Field Museum, laid out the story behind the fossil in a paper published today by the Journal of Vertebrate Paleontology.
Antarctanax shackletoni takes its scientific name from the ancient Greek words for “Antarctic king” and from early-20th-century polar explorer Ernest Shackleton.
An artist’s conception shows the desolation caused by the Permian-Triassic extinction more than 250 million years ago. (LPI / USRA Illustration)
Scientists say rapidly warming oceans played a key role in the world’s biggest mass extinction, 252 million years ago, and could point to the risks that lie ahead in an era of similarly rapid climate change.
The latest analysis, published in this week’s issue of the journal Science, puts together computer modeling of ancient ocean conditions and a close look at species characteristics to fit new pieces into a longstanding puzzle: What were the factors behind the Permian-Triassic mass extinction, also known as the Great Dying?
Carlos Mauricio Peredo, a researcher at the National Museum of Natural History, shows off a 33 million-year-old whale fossil that has been newly classified with the name Maiabalaena nesbittae. (Smithsonian Photo)
A whale that lived 33 million years ago when present-day Oregon was part of the ocean floor has been newly named after a curator at the Burke Museum of Natural History and Culture in Seattle.
And Elizabeth Nesbitt’s whale isn’t your typical cetacean: An analysis of the fossil, published in the Nov. 29 issue of Current Biology, suggests that Maiabalaena nesbittae bridged a gap between species of whales that had teeth and species that have a different mouth-feeding mechanism known as baleen.
“For the first time, we can now pin down the origin of filter-feeding, which is one of the major innovations in whale history,” study co-author Nicholas Pyenson, the National Museum of Natural History’s curator of fossil marine mammals and an affiliate curator at the Burke Museum, said in a news release.
Christian Sidor, Burke Museum curator of vertebrate paleontology and a biology professor at the University of Washington, recounts the discovery of Triassic fossils. (GeekWire Photo / Alan Boyle)
More than 100 fossil specimens at Seattle’s Burke Museum provide a fresh window into how life thrived in Antarctica about 250 million years ago, thanks to global warming.
The slabs of rock document a time in the early Triassic Era when temperatures got so warm that Earth’s tropics were a virtual “dead zone.” The flip side of that climate equation is that Antarctica, which was still connected to what’s now Africa back then, was temperate enough to support weird sorts of amphibians and other forms of life.
Burke Museum fossil preparator Bruce Crowley and volunteers Jean Primozich and Ben LeFebvre work on the museum’s T. rex skull. (GeekWire Photo / Alan Boyle)
The only Tyrannosaurus rex skull to go on public display in Washington state is getting its unveiling at Seattle’s Burke Museum of Natural History and Culture – and the best part is that you can watch as more and more of the skull is revealed.
“You can see those teeth coming out,” University of Washington biologist Greg Wilson, the museum’s curator of vertebrate paleontology, told GeekWire today at the big reveal. “And those teeth are gorgeous.”
As he spoke, a team of paleontologists and trained volunteers worked methodically in a glassed-in room, chipping at and brushing away the rock and sand that surrounded the fossil skull.
