Rare fossil of flying dinosaur reveals 76-million-year-old crocodile-like bite
A crocodile-like creature bit the neck of a flying dinosaur some 76 million years ago – and scientists have proof.
Archaeologists found the fossilized neck bone of the young pterosaur in Canada's Dinosaur Provincial Park.
'Bite traces help to document species interactions from this period,' Dr Brian Pickles, from England's University of Reading, said in a statement.
'We can't say if the pterosaur was alive or dead when it was bitten but the specimen shows that crocodilians occasionally preyed on, or scavenged, juvenile pterosaurs in prehistoric Alberta over 70 million years ago.'
Pickles is a co-author of a paper announcing the finding that was published Wednesday in the Journal of Palaeontology.
The discovery was made during an international field course led by Pickles in July 2023. The Alberta state park has produced some of the most important dinosaur fossil discoveries ever made, including 35 species dating back some 75 million years.
The vertebra has a circular, four-millimeter-wide puncture mark from a crocodilian tooth.
Researchers say the finding provides insight into the dynamics between predators and their prey in the region during the Cretaceous Period.
They took micro-CT scans, which are often used to diagnose disease or injury, and comparisons with other pterosaur bones to confirm the puncture was the result of a bite and not just damage during its fossilization.
The fossil belongs to a young Azhdarchid pterosaur, also known as Cryodrakon boreas, with an estimated wingspan of 6.5 feet, according to the University of Reading.
Adults of this species would have been as tall as a giraffe, boasting a wingspan of up to 32 feet.
The paper also says this bone is the first evidence in North America of ancient crocodilians opportunistically feeding on these giant prehistoric flying reptiles. Other examples of Azhdarchid bones with possible crocodilian bites have previously been found in Romania.
'Pterosaur bones are very delicate – so finding fossils where another animal has clearly taken a bite is exceptionally uncommon. This specimen being a juvenile makes it even more rare,' the paper's lead author Dr. Caleb Brown, of the Royal Tyrrell Museum of Palaeontology, said.
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Yahoo
3 days ago
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Ancient fossils show how the last mass extinction forever scrambled the ocean's biodiversity
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What happened to these creatures during the extinction event and how they rebounded tells an important story, both about the past and the future of biodiversity. Marine bivalves lost around three-quarters of their species during this mass extinction, which marked the end of the Cretaceous Period. My colleagues and I – each of us paleobiologists studying biodiversity – expected that losing so many species would have severely cut down the variety of roles that bivalves play within their environments, what we call their 'modes of life.' But, as we explain in a study published in the journal Sciences Advances, that wasn't the case. In assessing the fossils of thousands of bivalve species, we found that at least one species from nearly all their modes of life, no matter how rare or specialized, squeaked through the extinction event. Statistically, that shouldn't have happened. Kill 70% of bivalve species, even at random, and some modes of life should disappear. 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CNN
31-05-2025
- CNN
While you sleep, these bugs throw a party on your face
Sign up for CNN's Sleep, But Better newsletter series. Our seven-part guide has helpful hints to achieve better sleep. As you fall asleep each night, you can take comfort in knowing you are never truly alone — thanks to the dozens of eight-legged mites crawling out of your pores to party. You can't see or feel these nocturnal crawlers, called demodex mites, but like almost every adult, you have them all over your body. Smaller than a pinpoint, the tiny invertebrates, which measure about 0.15 millimeters to 0.4 millimeters in length, live around the outer parts of hair follicles and feed on their oily contents. 'While we are sleeping, they come out and are very happy, mating, visiting relatives, walking on our faces. The moment we wake up, they go back inside the pore,' said Alejandra Perotti, an associate professor of invertebrate biology at the University of Reading in England. If you're creeped out, Perotti said, 'don't be.' Demodex mites are more often friends than foes. 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CNN
30-05-2025
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These bugs mate on your face as you sleep. Are they friends or foes?
Sign up for CNN's Sleep, But Better newsletter series. Our seven-part guide has helpful hints to achieve better sleep. As you fall asleep each night, you can take comfort in knowing you are never truly alone — thanks to the dozens of eight-legged mites crawling out of your pores to party. You can't see or feel these nocturnal crawlers, called demodex mites, but like almost every adult, you have them all over your body. Smaller than a pinpoint, the tiny invertebrates, which measure about 0.15 millimeters to 0.4 millimeters in length, live around the outer parts of hair follicles and feed on their oily contents. 'While we are sleeping, they come out and are very happy, mating, visiting relatives, walking on our faces. The moment we wake up, they go back inside the pore,' said Alejandra Perotti, an associate professor of invertebrate biology at the University of Reading in England. If you're creeped out, Perotti said, 'don't be.' Demodex mites are more often friends than foes. 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Immunodeficient individuals, such as older adults or people on chemotherapy, are more vulnerable to demodicosis and may have an inflammatory response to the mites and the bacteria that can colonize them, Locksley said. It's not totally known why some people experience inflammation from the mites, Locksley said. 'But what is known is that wild animals don't have any diseases from the mites, but domestic dogs and cats do. So perhaps when we moved into a different environment, and the way we evolved, a genetic mutation compromised our immune pathways.' The inflammation can manifest as rosacea, acne, dryness and flaking, especially on the cheeks, eyelids, forehead and creases where oil may accumulate, said Dr. Roberto Ricardo-Gonzalez, associate professor of dermatology at University of California, San Francisco, who worked closely with Locksley to research the mites. To determine whether demodex mites are the cause of skin irritations, dermatologists can tape or lightly scrape the top layer of skin and place the sample under a microscope, Ricardo-Gonzalez said. During a routine eye exam, the doctor may check for a waxy buildup of demodex eggs and waste around the base of the eyelashes. said Dr. Cory Lappin, an Ohio optometrist. For patients with eyelid infections, this buildup is a common cause of dryness, itchiness, eyelash loss and even recurrent sties. For most healthy adults, there is no need to panic about demodex mites. 'Most people are completely unaware they have the mites, and (it) should stay that way,' Locksley said. 'You could do more harm picking around looking for problems than just being agnostic about it. And if you have problems, you should go talk to a physician first.' 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And since they are passed down between related humans, the populations lack genetic diversity — in other words, they are inbred. It's unknown how long the extinction will take, but to Perotti, this is nothing to celebrate — or mourn — considering humans will likely adapt to need demodex mites less as they die out. 'There has been very bad talk about the mites for a long time. They have been blamed for a lot of problems, but the suppressed immune system is the problem, not the mite itself,' Perotti said. 'We should think of them as our companions.'
