Tag Archives: predators

Top Ocean Predators Thrive Even After Earth’s Largest Mass Extinction

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Artwork of Hibodus Sharks

Artwork of Hibodus sharks—predators from the late Permian period that outlasted mass extinctions.

Credit: Christian Darkin/Science Photo Library

The largest mass extinction in history led to the loss of over 80% of marine life. Remarkably, certain ecosystems continued to thrive, and various species, including apex predators, managed to survive this catastrophic event.

This research indicates that the survival of specific ecosystems was influenced by their unique species compositions. A similar pattern may be observed in today’s marine ecosystems, which are under significant threat from climate change.

Approximately 252 million years ago, the end-Permian extinction was likely triggered by extensive volcanic eruptions in present-day Siberia, causing rapid global warming and diminishing ocean oxygen levels. Notably, some groups, like trilobites and eurypterids (sea scorpions), faced total extinction, while others experienced dramatic losses. In the aftermath, new species groups emerged, including dinosaurs and ichthyosaurs.

Despite the extinction of numerous species, researchers speculate that ecosystems may have become less complex. A functioning ecosystem relies on diverse interdependent species—plants that produce energy, herbivores that consume them, and predators that eat herbivores. Top predators may face extinction as they depend on prey for survival. Thus, a significant extinction event, such as the one at the end of the Permian, would simplify ecosystems.

To investigate this hypothesis, Baran Kalapunar and a team from the University of Leeds assessed preserved remains from seven marine ecosystems globally, both before and after the extinction. They analyzed the ecosystem structures based on the species present. Kalapunar declined to provide an interview as the study is yet to undergo peer review.

Even with species losses reaching 96%, five of the seven ecosystems sustained at least four trophic levels.

In regions, particularly near the poles, slow-moving herbivores caused the most significant damage, while free-swimming organisms, such as fish, were less severely impacted.

Ecosystem recovery varied based on proximity to the equator. Tropical ecosystems were primarily populated by low-trophic-level species, while those nearer to the poles experienced the addition of trophic levels as fish predators relocated away from extreme heat near the equator.

These findings imply that present-day marine ecosystems also respond differently to climate change and other anthropogenic impacts.

“I’m not aware of any other study that encompasses so many regions,” states Peter Roopnarine from the California Academy of Sciences in San Francisco. He concurs with the conclusions that many ecosystems sustain trophic levels despite extinctions, as previous smaller-scale studies indicated.

However, Roopnarine cautions against placing too much emphasis on the specifics of researchers’ ecosystem models. The fossil record does not clarify which organisms survived and which did not, requiring researchers to combine all photosynthetic organisms together without predicting outcomes if these species became extinct. “These findings are firmly supported by the fossil record, yet it remains incomplete,” he remarks.

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Ancient 280-Million-Year-Old Fossil: The Earliest Evidence of Land Predators Hunting Herbivores

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Paleontologists from the University of Toronto Mississauga have uncovered numerous tooth impressions in the fossilized bones of three juvenile Diadectes, one of the earliest large herbivorous vertebrates to traverse land. This groundbreaking finding represents the earliest direct evidence of predator-prey interactions between terrestrial carnivores and herbivores.

Skeletal reconstruction of Diadectes sideropelicus. Side view illustrating left and right tooth and hole marks. Image credit: Young et al., doi: 10.1038/s41598-026-38183-6.

Paleontologists have long been aware of the existence of apex predators in the Permian landscape; however, clear physical evidence confirming their dependence on the early large herbivores has remained elusive.

In contrast to the Mesozoic Era, renowned for its dinosaur bite marks, the earlier fossil record reveals scant direct evidence of such predator-prey encounters.

“Our findings indicate that the predator-prey hierarchy emerged earlier than previously understood,” stated lead author Professor Robert Rice, a paleontologist at the University of Toronto Mississauga.

“While these interactions are well-documented in the ‘age of reptiles,’ there has been limited information regarding them in the Paleozoic era, when terrestrial vertebrates first evolved into large apex predators and herbivores.”

In this study, Professor Rice and colleagues analyzed the disarticulated skeletons of three juvenile Diadectes, dating back to the early Permian period.

The fossils were unearthed in the Mud Hill area of the Vale Formation located in Texas, USA.

The paleontologists documented five distinct types of bone damage: shallow notches, deeper holes, grooves along the shafts, conical punctures, and small holes.

Notably, many marks were concentrated around cartilage-rich joints, indicating predators had stripped away muscle and pried open connective tissues.

Some grooves ran parallel to the long axis of the bone, consistent with the motion of tearing flesh.

“The holes, pits, cuts, and wrinkles present on these three juvenile herbivores’ skeletons point to the presence of large predators in this area, such as Varanopus and Dimetrodon,” said lead study author Jordan M. Young, a researcher at the University of Toronto Mississauga.

“Scavengers and small arthropods also took part in this ‘Paleozoic feast.’”

Evidence of arthropod perforation was found where the cartilage of the bone ends would have been.

The study was published in the Journal on February 26, 2026, in a Scientific Report.

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JM Young et al. 2026. The earliest direct evidence of trophic interactions between terrestrial apex predators and large herbivores. Scientific Reports 16, 6977; doi: 10.1038/s41598-026-38183-6

Source: www.sci.news

700-Million-Year-Old Fossils of Crocodile-Like Apex Predators Discovered in Argentina

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Paleontologists have unearthed exquisitely preserved skulls and jaws, along with parts of the skull and jaws belonging to a previously unidentified species of Peilosaurus in Patagonia, Argentina.

Reconstruction of Kostensuchus atrox. Image credit: Gabriel Dias Janten.

Kostensuchus atrox roamed the Earth during the Cretaceous period approximately 70 million years ago.

This ancient species was a formidable predator, measuring about 3.5 m (11.5 feet) in length and weighing around 250 kg.

These animals featured broad, powerful jaws and large teeth capable of consuming substantial prey, including medium-sized dinosaurs.

Kostensuchus atrox was a member of the Peirosauridae family of crocodiles within the sub-order Notosuchia.

“This new species belongs to the notosuchian clade Peirosauridae, representing the latest and southernmost records of this crocodile-like group,” stated Dr. Fernando Novas, a paleontologist at Argentino de Ciencias Naturales ‘Bernardino Rivadavia.

The fossilized skulls and bones of Kostensuchus atrox were discovered in the Chorrillo Formation, approximately 30 km southwest of El Calafate in the province of Santa Cruz.

“The Chorrillo Formation dates back about 70 million years,” the paleontologist explained.

“At that time, southern Patagonia boasted a warm, seasonally humid environment filled with freshwater floodplain plants, home to dinosaurs, turtles, frogs, and various mammals.”

“The newly excavated fossils from this layer are almost complete, including skulls and jaws exhibiting visible details, along with multiple bones from the body.”

Kostensuchus atrox ranks as the second-largest predator identified in the Chorrillo Formation and likely served as one of the region’s top predators.

This new species is also the first crocodile-type fossil found in this geological layer and is among the most intact examples of a crocodilian ever discovered, offering scientists unique insights into these prehistoric creatures and their environments.

“The discovery of Kostensuchus atrox significantly enhances our understanding of the anatomy of the widely distributed Peilosaurus population, which was previously known from highly fragmented specimens found in South America and Madagascar,” the researchers noted.

“The new anatomical data illuminate both the similarities and distinctions between the extensive Peirosauridae and Baurosuchidae, other crocodile-like lineages that evolved independently into apex predators during the Cretaceous period in Gondwana.”

“Kostensuchus atrox provides insights into late Cretaceous ecosystems in southern Patagonia, which formed in freshwater habitats within warm climates, supporting diverse faunas of dinosaurs, mammals, and other vertebrates in a seasonally humid environment,” they added.

“The wide and tall snout of Kostensuchus atrox, particularly its robust forelimb anatomy, along with large, sturdy teeth and broad adductor chambers in the skull, suggests this new species was capable of overpowering substantial prey.”

“These characteristics indicate that Kostensuchus atrox occupied the role of the top predator within this ultimate Cretaceous ecosystem.”

The discovery of Kostensuchus atrox is detailed in a paper published this week in the journal PLOS 1.

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Fe Novas et al. 2025. A new large carbonized crocodile from the Maastrichtian in southern Patagonia, Argentina. PLOS 1 20(8): E0328561; doi: 10.1371/journal.pone.0328561

Source: www.sci.news

Fossils of Terrestrial Apex Predators Dating Back Six Million Years Unearthed in the Dominican Republic

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A recent study conducted by the Florida Museum of Natural History reveals that this apex predator is a type of Cebucid crocodile with origins in South America.

The Cebushid crocodile ruled the South American landscape after the dinosaurs vanished, remaining dominant until roughly 11 million years ago. Image credit: Jorge Mackey.

The sebecids were the last survivors of notosuchia, a large and varied group of extinct crocodiles with fossil records that trace back to the era of dinosaurs.

Notosuchians exhibited a wide range of sizes, diets, and habitats, distinguishing themselves from their alligator relatives, as most inhabited terrestrial environments.

The Sevecid behaved like a carnivorous dinosaur, sprinting with four long, agile limbs and tearing flesh with its notorious teeth.

Some species were equipped with protective armor made of bone plates embedded in the skin, reaching lengths of up to 6 m (20 feet).

The catastrophic mass extinction at the end of the Cretaceous period, which eradicated non-avian dinosaurs, also nearly led to the extinction of the notosuchians.

In South America, only the Sevecids survived post-dinosaurs, quickly ascending to the role of apex predators.

The open waters separating the Caribbean islands from the South American mainland posed significant challenges for the Sevensids when it came to swimming.

In a new research effort, paleontologist Jonathan Bloch and his colleagues from the Florida Museum of Natural History analyzed vertebrae from fossilized teeth and spinal vertebrae dating back six million years, collected from the Paleopoultry 1 site in Savanna Grande de Boya, Dominican Republic.

“Our first question upon discovering these teeth in the Dominican Republic and other Caribbean islands was: what could they be?” Dr. Bloch mentioned.

The team also examined 18 million-year-old teeth found in Cuba and 29 million-year-old specimens from Puerto Rico.

“The fossils suggested evidence supporting the Girllandia hypothesis,” they noted.

This theory posits that a temporary land bridge or chain of islands enabled the migration from South America to the Caribbean.

“If the serrated teeth found in other Caribbean islands also belong to the Sevecid, the history of these giant reptiles stretches beyond just the Dominican Republic.”

“They would have played a significant role in shaping the ecosystems of this region for millions of years. However, today, evidence of large terrestrial predators is scarce.”

“In their absence, smaller endemic predators like birds, snakes, and crocodiles have evolved to fill gaps in the food chain,” he added.

“We could not have predicted this just by studying modern ecosystems,” Dr. Bloch remarked.

“The presence of large predators greatly differs from our previous assumptions, and it’s thrilling to explore what further discoveries might await in the Caribbean fossil record.”

The team’s paper was published in Proceedings of the Royal Society B.

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Lázaro W. Viñola López et al. 2025. The South American Sevecid from the Miocene of Hispaniola documents the presence of apex predators in the ecosystems of the Early West Indies. Proc. R. Soc. B 292 (2045): 20242891; doi: 10.1098/rspb.2024.2891

Source: www.sci.news

Birds Build Nests with Snake Skin to Protect From Predators

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Many species of birds use shed snake skin when building nests, but this behavior is poorly understood. In a new study, Cornell University ornithologists used comparative and experimental approaches to suggest that the evolution of this behavior is mediated by nest morphology and predator community. They used a series of experiments and comparisons to test four hypotheses (nest predation, nest microbiota, nest ectoparasites, and social signaling) that snake skin confers fitness effects, and the predation hypothesis found support for.

Great Crested Flycatcher (Myialchus crinitus) are famous for using snake skin to construct their nests. Image credit: Barbara Taylor/Macaulay Library.

“What do snakes eat? They eat a lot of rats and small mammals,” said Dr. Vanya Lower, lead author of the study.

“Given the evolutionary history of harmful interactions between small-bodied predators that are commonly eaten by snakes, these predators should become fearful of snake skin in their nests.”

“It may change the decision-making process for whether or not to nest.”

“Birdwatchers have been recording the use of snakeskin in nests for centuries, and have speculated that snakeskin occurs more frequently in hollow nests, but no one has tested this theory. There was no one there.”

“We were trying to understand why birds spend so much time and effort finding this strange substance.”

First, Dr. Lower and his colleagues looked at the literature and found that 78 species in 22 families have been reported to use shed snake skin for nest building.

All but one of these species are passerines, and in a comparative analysis, the researchers found that this behavior was disproportionately observed in cavity-nesting species.

Next, they examined a subsample of North American species, all of which are reported to use snake skin for nest construction, and found that between cavity-nesting species and open-cup nesting species, snake skin We investigated whether the proportion of nests with

The analysis suggested that the proportion of nests with snake skin was approximately 6.5 times higher in cavity nests than in open cup nest species.

“The proportion of nests that had snake skin in the nest description was about 6.5 times higher in cavity nests than in open cup nests,” Dr. Lower said.

“This was really, really cool and suggested to us that these two completely independent data series were telling very similar stories.”

To test the benefits that cavity-nesting birds derive from snake skin, scientists investigated how snake skin reduces nest predation, reduces harmful nest ectoparasites, and benefits birds. We investigated whether they can alter the microbial community or serve as a signal of parental quality. Parents make more efforts to raise their children.

Of these ideas, the results supported the nest predation hypothesis, but only in cavity nests.

For the experiment, the authors placed two quail eggs in more than 60 nest boxes and more than 80 inactive robin nests set up around Ithaca’s Monkey Run Natural Area. Cavity nests and open cup nests were simulated.

Some nests received snake skins collected from local snake breeders, while others did not.

Every three days for two weeks, the team used a ladder to climb through the monkey run to the nest and check for eggs.

Trail cameras revealed that while small mammal and bird nest predators visit open cup nests, only small mammals, namely flying squirrels, visit nest boxes.

“If you were in a hive like that and you had snake skin, you would have a much better chance of surviving those 14 days,” Dr. Lower said.

“The benefits of the material are most strongly expressed in hollow nests.”

team’s result appear in american naturalist.

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Vanya G. Lower others. Evolution of the use of snake skin in bird nests. american naturalistpublished online on December 17, 2024. doi: 10.1086/733208

This article is a version of a press release provided by Cornell University.

Source: www.sci.news

Research: Teeth of saber-tooth predators proved to be extremely efficient in piercing their prey.

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Saber-toothed tiger predators — such as the famous saber-toothed tiger Smilodon Fatalis — evolved multiple times between different mammalian groups. Their unusual teeth were functionally optimal and highly effective at stabbing prey, a new study led by researchers has found. University of Bristol Paleontologist.

Graphics illustrating optimal functionality repeat the evolution of the extreme sabertooth shape. Image credit: Talia Pollock.

Dr Talia Pollock from the University of Bristol said: “Our research helps us to better understand how extreme adaptations evolve, not just in saber-toothed predators, but throughout nature.” Ta.

“By combining biomechanics and evolutionary theory, we can reveal how natural selection shapes animals to perform specific tasks.”

Dr. Pollock and his colleagues used 3D-printed steel tooth replicas in a series of occlusal experiments and advanced computer simulations to analyze the shape and performance of teeth in 95 different carnivorous mammal species, including 25 saber-toothed species. .

They discovered that the long, sharp, blade-like teeth gave the sabertooth a real advantage as a specialized weapon for capturing prey.

This discovery helps explain why saber teeth have evolved so many times, at least five times independently in mammals, and also explains the possible eventual demise of saber teeth. There are also things.

Their increased specialization may have acted as an evolutionary ratchet, making them highly effective hunters, but would put them at greater risk of extinction as ecosystems change and prey becomes scarce.

Another important finding challenges the conventional idea that saber-toothed predators fall into two categories: dark-toothed and scimitar-toothed.

Instead, researchers found a variety of saber-tooth shapes ranging from long, curved teeth. barborofelis fricky For straighter and stronger teeth Dinofelis Barlowi.

This adds to a growing body of research suggesting that the hunting strategies of these predators are more diverse than previously thought.

The research team now plans to expand their analysis to all tooth types and uncover the biomechanical tradeoffs that have shaped the evolution of diverse tooth structures across the animal kingdom.

Professor Alistair Evans from Monash University said: “This discovery not only deepens our understanding of saber-toothed predators, but also has far-reaching implications for evolutionary biology and biomechanics.”

“Insights from this study could also help inform bio-inspired designs in engineering.”

The result is today journal current biology.

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Talia Pollock others. 2025. Functional optimality underpins the repeated evolution of extreme “sword-tooth” morphology. current biologyin press.

Source: www.sci.news

New Study Reveals Australian Marsupials Are More Afraid of Humans Than Other Predators

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Researchers from the University of Tasmania and Western University have conducted experiments to show that Australian marsupials such as kangaroos and wallabies are most afraid of human “super predators,” fleeing from them 2.4 times more frequently than from other predators.

Recent experiments have demonstrated that carnivores and ungulates from Africa, Asia, Europe, and North America fear human “superpredators” much more than they do other predators. Australian mammals have been the focus of research into predator ignorance because they are suspected of exhibiting atypical responses. To experimentally test whether Australian mammals are also most afraid of humans, McGann others quantified responses of four native marsupials (eastern grey kangaroo, Bennett’s wallaby, Tasmanian pademelon, and brushtail possum) and taught fallow deer to playback predator (human, dog, Tasmanian devil, wolf) or non-predator control (sheep) vocalizations. Image courtesy of Pen_ash.

There is a widespread fear of humans among wildlife in Africa, Asia, Europe, and North America, reflecting the reality that humans are “super-predators,” far more dangerous than other predators worldwide.

Australian marsupials have been traditionally seen as naive to predators, based on their reactions to non-human threats.

“Our results significantly contribute to the growing body of experimental proof that wildlife globally view humans as the most feared predators on the planet,” stated Professor Liana Zanetto of Western University, a co-senior author of the study published in the journal Nature Proceedings of the Royal Society B.

“The strong fear of humans found in this study, as well as in similar recent experiments, is expected to have significant ecological repercussions, as additional research indicates that fear itself can reduce wildlife populations and that fear of humans can lead to cascading effects on multiple species across entire regions.”

To conduct their study, Professor Zanette and colleagues designed a hidden automated camera-speaker system in a sheep pasture in central Tasmania known as the Bowfront.

The five species they observed (eastern grey kangaroo, Bennett’s wallaby, Tasmanian pademelon, brushtail possum, and fallow deer) are the most prevalent native herbivores in the area.

As the animals came close (about 10 meters, 30 feet), the cameras captured their responses to non-threatening stimuli such as calm human speech, a barking dog, growling Tasmanian devil, howling wolf, or bleating sheep.

Native marsupials reacted by fleeing more frequently when exposed to the sound of their next most feared predator (dogs) compared to human voices, and were over twice (2.4 times) more likely to flee from humans (44.3% vs. 18.6% of trials).

These findings present conservation challenges but also offer insights for managing native marsupials in regions where they are overpopulated.

“Global studies have shown that humans kill prey at a much higher rate than other predators, making us ‘super-predators,’ and the intense fear of our presence in all wildlife species aligns perfectly with our inherent deadliness,” noted Professor Zanette.

“Humans are the ‘invisible killer.’ We may not perceive ourselves as the primary predator, let alone the most dangerous, but wild animals clearly see us for what we truly are.”

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Catherine McGann et al. 2024. Fear of human “super-predators” in Australia’s native marsupials and invasive deer. Proceedings of the Royal Society B 291 (2023): 20232849; doi: 10.1098/rspb.2023.2849

Source: www.sci.news

During the Eocene, giant fearbirds ruled as the apex predators of Antarctica.

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Paleontologists have unearthed two fossilized phalanges of ancient carnivorous birds on Seymour Island in Antarctica.

Paleoenvironmental reconstruction of an early Eocene continental community on Seymour Island: large claw-shaped birds hunting and gazing at medium-sized ungulates. Nothiolophos regeloiseveral marsupials on the tree, Antarctoboenus carlinii It is flying in the sky, and behind it is a runner who cannot fly. Image credit: Carolina Acosta Hospitaleche & Washington Jones, doi: 10.26879/1340.

Ancient bird fossils were discovered in the La Meseta Formation on Seymour Island in West Antarctica.

“These phalanges belonged to a large predator, estimated to weigh around 100 kg,” said Dr. Carolina Acosta Hospitalrecce of the National University of La Plata and Dr. Washington Jones of the National Museum of History of Uruguay.

The specimen is approximately 50 million years old (early Eocene).

They belong to the following types Forsulacid (commonly known as the fear bird), an extinct family in the order Calliamyformes.

“Caryamiformes are a primarily terrestrial bird order that has shown significant diversification in the past, but only two species currently inhabit South America,” the paleontologists said.

“Despite the rich fossil record, phylogenetic and biogeographic relationships within this order remain poorly understood.”

“Within the Calliamydae, Phorsuracidae forms a crown group with the Caryamydae, and Idiornithidae and Basorhuntiidae have been reconfirmed as fossil families.”

Fossilized phalanx of an ancient Karyamiform bird from Seymour Island, Antarctica. Scale bar – 10 mm. Image credit: Carolina Acosta Hospitaleche & Washington Jones, doi: 10.26879/1340.

The Antarctic terror bird probably preyed on small marsupials and medium-sized ungulates.

“They are likely active hunters, clearly fulfilling the role of continental apex predators similar to the mammals of Paleogene Antarctic communities,” the researchers said.

“Large birds resembling Phorsulaceae represent a previously unknown guild in Antarctica.”

“These findings unequivocally reshape our understanding of the dynamics of the Antarctic ecosystem during the early Eocene.”

of result Published in an online magazine Old Trogia Electronica.

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Carolina Acosta Hospitalrecce & Washington Jones. 2024. Was the fearbird an apex predator in Antarctica? New discoveries from the early Eocene of Seymour Island. Old Trogia Electronica 27 (1):a13; doi: 10.26879/1340

Source: www.sci.news

Giant sea scorpions, the largest insects, were all predators.

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All pterosaur eurypterids (sea scorpions), giant aquatic arthropods with large claws, were considered apex predators, but some scientists believe that certain species are not predatory because their claws are weak. suggested. New research reveals that their claws were stronger and were only used to capture prey. Other appendages chewed it up. Fossils found in the pterosaur eurypterids show that some species specialized in lightly armored crustaceans and fishes, but most species specialized in heavily armored fishes.

Size of sea scorpions (Euripterids) over time.pterosaur eurypterid Jachelopterus (Background), the largest arthropod of all time, and a eurypterid of the Hibertopteridae family. Siltoctenus (Foreground) The size of a human (an average British male) compared to the silhouette of its eurypterid relatives. Image credit: Simon Powell.

Sea scorpions (family Eurypteridae) are ancient aquatic creepy crawlers (arthropods) that lived long before the dinosaurs, from 467 million to 253 million years ago.

These include the “pterygoids” (428 to 391 million years ago), which had large, fearsome claws. Grows up to 2.5 meters longthe biggest bug that ever existed.

An extinct millipede called Arthropleura was It is claimed that it is even largerHowever, if the length of 12 to 14 preserved body segments is 76 cm, the body length of an animal with 32 segments is (76/12 x 32), which is just over 2 m (excluding the head).

All pterosaurs, eurypterids, were thought to have been ferocious apex predators. tyrannosaurus About their time.

Later, some scientists believed that pterygoid claws acutiramus It could only catch and slice weak, soft-bodied prey, and its eyesight wasn't sharp enough Becoming a predator.It has been demoted from the top echelon of predators and even a label is attached “Pussycat”.

According to new research, nails acutiramus It was much more robust. Suggestions that they would snap were based on incorrect assumptions.

The apparent lack of an “elbow joint” doesn't hurt either. This was at the base of the nail. Also, the claws were used only for catching prey. If it had more powerful mouthparts in the groin, it would kill or chew it up.

It doesn't matter that their eyesight is poor either. Their prey is large, and some non-predatory insects (such as bees and butterflies) have eye indicators similar to arthropods that were considered predators.

Computer modeling and experiments with robotic swimming eurypterids also show that pterosaurs were slower swimmers than expected. They were so large that relatively small swim paddles could not provide sufficient propulsion, so a flat tail (telson) served both as a rudder and as propulsion.

Analysis of the types of fossils found with pterygomorphs also suggests that: acutiramus It specializes in lightly armored crustaceans (called foliaceans) and pterophytes. Eretopterus Therodont fish and pterigotus and Jachelopterus About the more heavily armored placoderm fish.

Evidence of predation (claw marks) and fossilized feces (coprolites) confirm that some eurypterids ate armored fish, trilobites, and even other eurypterids.

Previous studies have generally dismissed suggestions that Eurypteridae influenced the evolution of early vertebrates (fish) in a predator-prey arms race, but this new study This suggests that pterosaurs and other eurypterids probably had some influence on the evolution of early vertebrates.

The evolutionary relationships of pterygoids have also changed. Their shape, vision, fossil associations, ecology, and stratigraphic record all indicate that: acutiramus It was more basic Jachelopterus and pterigotus.

This is the largest arthropod in history (Jachelopterus lenaniae) It is now estimated to be about 2.6 meters long, 10 centimeters longer than previous estimates. The biggest bug is now a little bigger.

this paper will appear in Earth Science Bulletin.

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S. J. Brady. 2023. Paleoecology of the pterygoid eurypterids: Pladicnia and paleontological assemblages. Earth Science Bulletin 98(4); doi: 10.3140/bull.geosci.1891

Source: www.sci.news

The Saber-Toothed Cat and the Direwolf: Prehistoric Predators

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Researchers found high rates of osteochondrosis in the joints of Ice Age saber-toothed tigers and dire wolves, based on more than 1,500 limb bones examined from the La Brea Tar Pits. This study suggests a potential link between the health problems of these ancient species and those of modern livestock. Credit: SciTechDaily.com

Studies have found that the incidence of osteochondrosis in these extinct predators is surprisingly high.

Ice Age saber-toothed tigers and direwolves had higher rates of bone disease in their joints, according to a recent study published in an open access journal. Pro Swan By Hugo Schmökel and colleagues at the Evidencia Academy in Sweden.

Ancient species of osteochondrosis

Osteochondrosis is a developmental bone disease known to affect joints. vertebrateincluding humans and various domestic animals. seed. However, the disease is not well documented in wild species, and published cases are extremely rare. In this study, Schmökel and colleagues identified signs of the disease in fossil limb bones of Ice Age saber-toothed tigers. (Smilodon fatalis) and dire wolf (Aenosion Dyras) Approximately 55,000 to 12,000 years ago.

Reconstructed photo of a dire wolf on display at the La Brea Tar Pits & Museum. Credit: La Brea Tar Pits and Los Angeles County Museum and Natural History Museum; CC-BY 4.0

Research results from the La Brea Tar Pits

Researchers examined more than 1,000 limb bones of saber-toothed tigers and 500 limb bones of dire wolves taken from the late Pleistocene La Brea Tar Pits, and found that many bones contained dissecting bones. They discovered small defects that matched certain symptoms of a bone disease called osteochondrosis (OCD). These defects were primarily found in the shoulder and knee joints, and their incidence was as high as 7% of the bones examined, significantly higher than that observed in extant species.

Implications and future research

Because this study was limited to bones isolated from a single fossil locality, further research on other fossil sites will reveal patterns of prevalence of the disease and from there provide insight into the lives of these animals. aspects may be clarified. For example, it remains unclear whether problems with these joints hindered the hunting ability of these predators. Additionally, OCD is common in highly inbred modern domestic dogs, so the high incidence of this disease in these fossil animals could be a sign that populations are declining as these ancient species approach extinction. It may be.

Detail of a 1911 illustration of a saber-toothed cat in the La Brea Tar Pits. Credit: Robert Bruce Horsfall & Natural History Museum of Los Angeles County; CC-BY 4.0

Connection with modern animals

The authors add: “The study adds: Smilodon Direwolf paleopathology made possible by La Brea Tar Pits & Museum’s unparalleled large sample size. This collaborative research between paleontologists and veterinarians shows that these animals, despite having survived harsh times and are now extinct large predators, share diseases with the dogs and cats in our homes today. It confirms what I was holding. ”

Reference: “Subchondral defects resembling osteochondrosis dissecans in the articular surfaces of the extinct saber-toothed cat Smilodon fatalis and the dire wolf Aenocyon dyrus,” by Hugo Schmökel, Aisling Farrell, and Mairin F. Balisi. July 12, 2023 Pro Swan.
DOI: 10.1371/journal.pone.0287656

Source: scitechdaily.com