Articles tagged with Bears
A study of ancient DNA from a 100,000-year-old polar bear genome found that extensive hybridization between polar bears and brown bears occurred during the last warm interglacial period. As a result, all living brown bears today have some polar bear ancestry.
A new study finds that polar bears and brown bears have a complicated evolutionary history due to interbreeding. The analysis of modern bear genomes and ancient DNA from a 115,000-year-old tooth reveals gene flow from brown bears into polar bears, challenging previous hypotheses.
Researchers analyzed polar bear fecal samples and dietary intake to understand how chemical contaminants accumulate inside the body. They found that polar bears store high amounts of fat, leading to higher levels of toxins in their bodies.
Researchers found varied diversity of gut microbiomes among brown bears at three national parks in Alaska, with Katmai showing the most diversity due to its diverse food sources. The study advances understanding of wildlife habitat, diet, and gut microbiome diversity.
A high protein diet may harm polar bears, with captive bears showing signs of kidney disease and shorter lifespans. Researchers propose adopting a diet with a fat-protein ratio similar to that found in the wild to improve bear health and longevity.
Researchers sequenced ancient DNA to understand lion and bear movement between continents. The study found that warm temperatures before the last Ice Age may have caused a change in plant abundance, affecting herbivores and predators.
A recent study by North Carolina State University and Northern Michigan University found that eating human food reduces microbial diversity in black bears' guts. The researchers analyzed gut samples from 35 bears and found lower biodiversity in those with a diet rich in processed foods.
A recent study found that polar bears in the Beaufort Sea are traveling up to 30% farther from their traditional hunting grounds, resulting in a 20% decrease in population. As sea ice recedes earlier and further, bears are being displaced from primary foraging habitats and forced to compete for food resources.
Researchers have found conclusive evidence that early humans made footprints at Laetoli Site A in Tanzania, contradicting the long-held theory that they were made by bears. The study reveals distinct differences between human and bear footprints, including a wide heel-to-toe ratio, which suggests bipedal locomotion.
Researchers found polar bears can be used as indicators of environmental shifts, highlighting how changes affect marine mammal prey populations. They also discovered that polar bears are flexible eaters and will consume available prey, making them an ideal monitoring tool for tracking environmental changes.
A 15-year study found that the availability of beech nuts can predict bear intrusions into human habitats. The research used numerical modeling and observed beech flowering patterns to forecast bear activity, reducing direct conflicts between humans and bears.
Researchers found that young female black bears in Asheville, NC, weigh nearly twice as much as those in national forests and reproduce at a younger age, producing cubs by their second birthday. The study's findings raise questions about the diet and foraging activities of urban bears.
Researchers found that human antibiotic use increased resistance to antibiotics in bears' bacteria, affecting even those far from civilization. The study suggests that reducing antibiotic use can help decline resistance rates.
Researchers analyzed oral bacteria of wild brown bears to track history of human antibiotic use and find significant decrease in antibiotic resistance after national policies were implemented. The study highlights the effectiveness of governmental policies in mitigating a major health threat on a national level.
Researchers in Peru have estimated the population density of spectacled bears and identified an unknown hotspot, revealing over 10 bears per 100 square kilometers. The team also observed the first 'golden' bear with nearly golden fur, sparking further investigation into its unusual characteristics.
A recent study suggests that near-death experiences (NDEs) in humans may be linked to evolutionary mechanisms, specifically thanatosis - the phenomenon of death-feigning or tonic immobility. This defense mechanism is thought to have arisen as a survival strategy in animals and has been preserved across various species, including humans.
Amblyopia researcher Mark F. Bear receives a $100,000 grant to develop a new treatment approach based on synaptic plasticity principles. The therapy aims to 'reboot' a formerly deprived eye, restoring vision more fully than traditional patch therapy.
Researchers used computer modelling to simulate bears' journeys in Whistler, identifying anthropogenic food as a major attractant. The study found that reducing attractants is more effective than reactive management strategies, and can be applied to communities across Canada
Russian paleontologists have discovered the skull of a 9-10 year old Pleistocene small cave bear with artificial damage, which could be evidence of ancient ritual practices. The finding is significant as it may be the world's first direct evidence of Paleolithic hunters targeting small cave bears.
Researchers found that black bears provided a top-down buffering effect, helping to protect gray foxes from coyote competition for food and space. However, this 'bear shield' was only seasonal and disappeared during bear hibernation.
Researchers found that landowners who have talked to a wildlife professional are more likely to secure attractants, emphasizing the importance of collective factors in improving wildlife-human coexistence. Effective communication and outreach could increase behaviors by highlighting social influence and neighborly norms.
A University of Alberta study finds that brown bears who rub against trees more often tend to have more offspring and more mates. The research team analyzed bear hair samples from over 900 rub sites and found a correlation between tree-grating behavior and reproductive success.
African and Asian leopards exhibit greater genetic differences than polar bears and brown bears, suggesting they should be treated as separate species. The study's findings have important implications for leopard conservation, highlighting the need for targeted strategies to maintain high genetic diversity.
Researchers from the Lundbeck Foundation GeoGenetics Centre have sequenced ancient DNA from soil for the first time, transforming the field of population genetics. The advance allows scientists to study the evolution of animals, plants, and microorganisms, with potential applications in climate change research.
Researchers measured grizzly bears' metabolic rates on flat and uphill gradients, finding they use less energy walking downhill. The study reveals why grizzlies often appear on human hiking trails, and provides insights for hiker safety.
A camera-trap study found that black bears are adept at finding and stealing the remains of adult deer killed by pumas. This 'kleptoparasitism' reduces the calories pumas consume, causing them to hunt more often and eat smaller prey when bears are not active.
A study published in FACETS highlights how misinformation and polarization are eroding conservation efforts worldwide. Researchers found examples of good intentions leading to harm, such as the case of Huemul deer in Patagonia National Park, Chile, where removing domestic livestock led to a decline in deer population.
A recent study highlights the alarming impact of Arctic sea ice loss on polar bears and narwhals. The mammals face severe challenges due to the loss of their primary food source and increased energy expenditure, leading to starvation and vulnerability to predators.
Researchers discovered that black bears' gut microbiomes are surprisingly simple and consistent throughout the intestinal tract. This finding has practical applications for wildlife researchers, as a fecal sample can provide insight into the entire gut microbiome.
Researchers found that polar bears in Kane Basin are healthier due to thinning sea ice, which allows more sunlight to reach the ocean surface. The bears are also traveling further to find food, but their long-term survival is uncertain.
Researchers from the University of Oklahoma and others report the first occurrence of the extinct giant short-faced bear, Arctodus simus, on the California Channel Islands. The toe bone was found to be from a bear dating back approximately 17,000 years, with chemical fingerprints matching the spectacled bear from South America.
Brown bears increasingly live among human settlements due to habitat loss, leading to conflict and high mortality rates. The study found that connected wilderness areas and nocturnal behaviors are crucial for coexistence between humans and bears.
Researchers sequenced ancient DNA from a 9,500-year-old dog, revealing that modern sledge dogs share a common origin with the ancient breed. The study also found genetic adaptations similar to those of polar bears and Arctic people.
A ten-year study on Asian black bears reveals diet variations based on age, sex, and seasonally abundant resources. Older bears are more carnivorous, while adult males consume more deer due to larger body mass.
Researchers found that large predators generally suppress smaller predators, providing more food in the form of leftover prey. However, the scavenging process can also be deadly for smaller carnivores, as they may be killed by their larger kin when returning to the kill site.
A study found that accounting for local perspectives when designing conservation policies may increase community support and improve their success. Local people's frustrations with policies were rooted in technical issues, lack of funding, and inadequate involvement in decision-making.
Polar bears in the Southern Beaufort Sea are abandoning their traditional summer habitats due to shrinking sea ice. As a result, they must expend more energy to find food and access whale carcasses, potentially contributing to population declines.
Research shows polar bears are spending more time on land, thinner and adult females have fewer cubs. Sea ice availability affects their body condition and reproductive success.
A team of scientists studied grizzly bears' muscles during hibernation and found that they produce non-essential amino acids, which can stimulate cell growth. This discovery could lead to the development of new methods to prevent and treat muscle atrophy in humans.
Researchers discovered that Asian black bears exhibit a twin-peak pattern of daily energy balance, peaking in spring and autumn. The study found that the bears obtain most of their energy by eating acorns in autumn.
Bears prefer small streams to catch salmon due to easy prey and early spawning times, which provide a crucial feeding opportunity after hibernation. This study highlights the importance of protecting smaller habitats in environmental impact assessments.
A Duke University study finds that baby pandas' bones mature at the same rate as other mammals, but are developed at an accelerated pace. The researchers used micro-CT scans to create 3D digital models of each baby's bony interior and discovered that giant panda skeletons are just like those of closely related animals, but smaller.
A new study reveals that polar bears at sea, particularly pelagic bears, accumulate more pollutants due to their diet rich in marine life closer to pollutant sources. This is attributed to increased energy requirements and longer periods without ice, forcing them to feed on land-based prey or rely on fat reserves.
Transboundary protected landscapes near the US-Canada border provide vital habitat for lynx and connections with larger Canadian populations. Climate change and increased border security pose significant threats to species conservation.
Grizzly bears express a larger number of genes than any other species studied to cope with hibernation-induced metabolic stressors. They reverse the negative effects of fat accumulation by switching genes on and off based on the season.
A study analyzing gene copy numbers in polar bears and brown bears reveals nearly 200 genes with significant variations, including those involved in olfactory receptors, salivary amylase, and fatty acid metabolism. These differences reflect dietary adaptations between the two species.
A recent study by UMass Amherst researchers found that polar bears possess fewer copies of genes related to olfactory receptors and salivary amylase, adaptations that enable them to thrive on a fully carnivorous diet. This discovery sheds light on the genomic foundation of ecological adaptation in polar bear evolution.
Researchers created a synthetic insulator mimicking polar bear hair's structure, which traps heat and is lightweight and water-resistant. The new material has exceptional stretchiness, making it suitable for aerospace applications.
A new mapping technique using satellite imagery helps track huckleberry distribution across Glacier National Park, enabling biologists to predict where grizzly bears will be found. This tool also aids in conserving the plant, which is crucial for the bears' survival and informs strategies to minimize human-bear conflicts.
Researchers found that sun bears can exactly mimic another bear's facial expressions, similar to humans and apes. This complex social skill suggests that other mammals may also possess advanced communication abilities.
The introduction of lake trout in Yellowstone Lake has altered the numbers, diet, and behavior of organisms from microscopic zooplankton to large animals such as bears and bald eagles. The study found that the impact of lake trout on native cutthroat trout has cascaded across the ecosystem.
The ancient people of Zhokhov Island in the High Arctic exchanged objects, including obsidian, through fairs. They practiced reindeer and polar bear hunting, with evidence suggesting a well-developed transport system that connected them to mainland territories.
Researchers at the University of Helsinki have identified a genetic defect in dogs that causes a rare metabolic bone disease similar to human hypophosphatasia. The study provides the first spontaneous animal model of the disease and may lead to the development of new therapies.
A study published in PLOS Biology warns that Alaska's management plan, which prioritizes reducing bear and wolf populations for hunters, lacks scientific monitoring and may interfere with important ecosystem services. The plan has led to an increase in reported brown bear hunting kills over the past three decades.
A recent study published in Ursus highlights the significance of water holes not only as drinking water sources but also as sites for Andean bears to communicate with each other. The locations of rubbed trees and shrubs near water holes were concentrated on trails, indicating potential conflicts between humans and bears.
A new study found that American black bears can habituate to repeated drone exposure, showing increased tolerance to the flights over time. The researchers suggest that other animals are less likely to adapt to such disturbances.
A study by Max Allen and colleagues found several mammalian predators, including gray wolves and American martens, living on islands with varying sizes and proximity to the mainland. The research offers new insights into island biogeography and highlights the importance of preserving carnivore habitats.
Scientists discover hundreds of unrecognized halogenated contaminants in polar bear serum, including polychlorinated biphenyls and perfluoroalkyl sulfonic acids. The study reveals increasing levels of these pollutants over the past two decades, posing potential health risks to the Arctic ecosystem.
A recent analysis estimates that suitable habitat for brown bears will decrease by 11 percent in Central Asia and the Asian Highlands due to climate change. This may force bears to move outside protected areas, highlighting the need for expanded protected areas and corridors.
Researchers found that female Asian black bears' teeth have narrower layers when they're raising cubs, indicating a decrease in reproductive success. This study provides a new tool to monitor and manage bear populations by analyzing tooth growth patterns.