Tag

Extinction

All articles tagged with #extinction

Genetic bottlenecks and hunting drove aurochs extinction in Scandinavia
archaeology5 days ago

Genetic bottlenecks and hunting drove aurochs extinction in Scandinavia

A new study reveals that aurochs vanished from Scandinavia thousands of years earlier than elsewhere in Europe due to a combination of genetic bottlenecks, intense hunting, and habitat loss. Researchers analyzed ancient DNA from bones found in bogs and settlement sites in southern Sweden and Denmark to reconstruct the population history of these wild cattle ancestors. The findings indicate that while the species survived globally until the 17th century, the Scandinavian population collapsed around 6,500 years ago. This early extinction was driven by a sharp drop in genetic diversity during their initial migration north, followed by isolation when rising seas flooded land bridges to mainland Europe. Concurrently, increased human settlement and hunting pressure, combined with the expansion of dense forests that reduced grazing land, led to the final disappearance of the species in the region.

Feather in Dino Poop Hints at Birds' Survival After the Dinosaur Era
science22 days ago

Feather in Dino Poop Hints at Birds' Survival After the Dinosaur Era

A remarkably preserved bird feather was found inside fossilized dinosaur dung from the Hell Creek Formation in Montana. Described as the best-preserved feather of its kind and the only known non-flattened dinosaur-era feather in rock, the specimen, analyzed by Jingmai O’Connor of the Field Museum and reported in Current Biology, offers new clues about how some bird lineages may have survived the mass extinction at the end of the dinosaur era.

Feathers in dinosaur poop unlock why birds survived the mass extinction
science24 days ago

Feathers in dinosaur poop unlock why birds survived the mass extinction

Researchers analyzing a coprolite (fossilized dinosaur dung) from Montana’s Hell Creek Formation found a tiny feather and other remains that suggest a small diving bird related to hesperornithiforms may have struggled to survive the asteroid-driven “impact winter.” The study proposes that modern birds (Neornithes) persisted because their feather traits differed enough to withstand the post‑impact cooling, while the primitive feather types did not insulate as well. Scientists say confirming this would require a pre‑asteroid Neornithes fossil preserved with enough detail, but the coprolite work shows how such fossils can illuminate why some lineages survived mass extinctions.

Feather in Dino Dung Offers Clues to Birds’ Survival After the Mass Extinction
science24 days ago

Feather in Dino Dung Offers Clues to Birds’ Survival After the Mass Extinction

Researchers analyzed a 66-million-year-old feather preserved in dinosaur dung and suggest that differences in feather insulation helped Neornithes—the modern birds—survive the asteroid-triggered winter, potentially explaining why this lineage endured while others did not; the dung also yielded hesperornithiform remains, illustrating an evolutionary bridge in feather type. Published in Current Biology, the study advocates CT-scanning more fossil dung to uncover additional clues about avian survival.

Tasmanian tiger skull reveals a fast-snapping passer of small prey, not a wolf-like predator
science1 month ago

Tasmanian tiger skull reveals a fast-snapping passer of small prey, not a wolf-like predator

New skull analysis shows the Tasmanian tiger hunted small prey with a long, slender snout and a very large skull that enabled rapid snapping, not the grappling, wolf-like predation once assumed. The marsupial was more closely related to kangaroos than dogs. The last captive thylacine died in 1936, and while de-extinction efforts are underway in some labs, researchers emphasize Indigenous stewardship and broader conservation lessons.

Extinction Bursts, Not a Schedule: Fossil Record Shows Clustered Losses
science1 month ago

Extinction Bursts, Not a Schedule: Fossil Record Shows Clustered Losses

The fossil record reveals extinction events are clustered rather than occurring on a regular timetable. David Raup’s kill-curve linked the size of an extinction episode to its average waiting time: about 10% of species lost roughly every 1 million years, around 30% about every 10 million, and about 65% roughly every 100 million. These are historical averages and do not predict when the next crisis will occur. Extinctions have been driven by diverse causes (asteroid impacts, volcanism, climate shifts, ocean chemistry), and newer data correct for sampling biases; there is no universal “mass-extinction clock.” Yet today’s biodiversity loss is real and accelerated by human actions, underscoring that the absence of a countdown doesn’t mean the threat is any less urgent.

Ancient oceans suffocated by heat; today’s warming echoes a deadly drop in ocean oxygen
science1 month ago

Ancient oceans suffocated by heat; today’s warming echoes a deadly drop in ocean oxygen

A 2026 PNAS study used lab measurements of oxygen use across major marine groups and a trait-based model to show that warming during the end-Permian increased animals’ oxygen demand while lowering dissolved oxygen, producing habitat loss and select extinctions. The results explain why certain groups vanished and others persisted, supporting the idea that temperature-dependent hypoxia helped drive the crisis. The piece also notes that today’s oceans are warming and deoxygenating, but this is not a direct forecast of another end-Permian-scale extinction; magnitudes, timescales, and co-stresses like acidification differ, and more cross-species, regional data are needed to gauge current risks.

Wrangel Island mammoths vanished abruptly after millennia of genetic stability
science1 month ago

Wrangel Island mammoths vanished abruptly after millennia of genetic stability

A 2024 genome study of Wrangel Island mammoths found the population did not slowly decline from inbreeding; instead, it remained genetically stable for thousands of years before an abrupt disappearance, leaving the exact cause unresolved and suggesting that sudden environmental or random events, rather than gradual genetic decay, ended the lineage. The work emphasizes that restoring population size in conservation isn’t enough—genetic health must also be monitored over long timescales.

Ancient Saber-Toothed Cats Were Health-Compromised by Inbreeding, Study Says
science1 month ago

Ancient Saber-Toothed Cats Were Health-Compromised by Inbreeding, Study Says

A study of more than 3,700 vertebrae from around 849 Smilodon fatalis individuals found widespread congenital defects—over 200 vertebral malformations, nearly 50 fused vertebrae, and signs of spinal nerve tumors—indicating severe inbreeding and genetic problems in the species before their extinction about 12,000 years ago. While DNA cannot be analyzed from these fossils, the findings from the La Brea Tar Pits suggest inbreeding may have contributed to the decline, highlighting risks faced by modern small populations facing habitat loss and climate change.

Geology-Driven Catastrophe: How Chicxulub Turned a Space Rock into a Global Climate Crisis
science2 months ago

Geology-Driven Catastrophe: How Chicxulub Turned a Space Rock into a Global Climate Crisis

A 10-km asteroid hit the Yucatán 66 million years ago, vaporising sulfur-rich rocks beneath it and lofting sulfur-bearing gases and dust into the atmosphere; the impact angle and local geology amplified the effect, triggering global cooling and a mass extinction, though the exact atmospheric recipe is still being refined by researchers.

New Skull Study Rewrites the Dodo’s Brainy Image
science2 months ago

New Skull Study Rewrites the Dodo’s Brainy Image

A high-resolution CT analysis of three preserved dodo skulls shows the bird’s forebrain was proportionate to other pigeons, suggesting similar cognitive abilities and challenging the stereotype of a stupid dodo; the extinction on Mauritius after humans arrived likely reflected ecological factors rather than inherent dimness, with hints the dodo may have foraged in low-light conditions due to smaller optic lobes.

Dodo skulls reveal sharper senses and dusk foraging
science2 months ago

Dodo skulls reveal sharper senses and dusk foraging

CT-scanning the two only complete dodo skulls (plus a third) enabled researchers to reconstruct endocasts and compare the dodo’s brain with those of pigeons, doves, and the Rodrigues solitaire. The results suggest the dodo may have foraged at dawn and dusk, had a stronger sense of smell, and used its large upper beak to feel its surroundings, implying it was smarter than many birds and offering new insights into how it lived and why it went extinct.

Dust from the Chicxulub impact could have fueled global firestorms hotter than previously imagined
science2 months ago

Dust from the Chicxulub impact could have fueled global firestorms hotter than previously imagined

A new study argues that a thick layer of fine silicate dust formed from rock vapor at the Chicxulub impact may have trapped heat and amplified Earth's post-impact heat pulse to about 3.5 times higher than models considering only the spherules, potentially igniting grass, lichens, and pine needles and delivering roughly 17 times the lethal thermal dose to exposed animals. This dust layer could also help block sunlight, fueling a prolonged “impact winter.” Global wildfire evidence is not yet confirmed beyond North America, but the proposed mechanism is published in JGR Biogeosciences (July 28).