Articles tagged with Mammals
Researchers have discovered that multiple ancient groups of crocodyliforms were not the carnivores they are known for, but rather plant-eaters. The study found evidence of herbivory in extinct relatives of modern crocodiles up to six times, suggesting a wide range of dietary ecologies.
Researchers developed a new metric called The Last of the Wild in Each Ecoregion (LWE) to quantify ecologically intact ecosystems. However, testing LWE against another method found neither to accurately capture the abundance of large mammal species sensitive to human disturbance.
Researchers observed ravens exhibiting negative emotional contagion when watching demonstrator ravens with induced negative emotional states. The results suggest convergent emotional evolution in birds and mammals.
A new study finds that hunting is reducing large mammal populations by 40% in intact tropical forests. Hunting impacts are expected to be high in areas with high human population density and hunter access points.
Research in southern Italy found that otters eat 12% of their prey items, including 28 species, with increased predation in Alpine regions during winter and spring. This suggests a previously underestimated threat to small amphibian populations.
Scientists estimated that 1.177 megatonnes of carbon would be lost if all predicted habitat were colonized by beavers, impacting large terrestrial carbon sinks. Invasive mammals like North American beavers pose a significant threat to carbon sequestration in riparian forests.
Researchers found that birds have significantly lower cellular rates of energy use and antioxidant capacity compared to mammals. This may contribute to their longer lifespans, as oxidative stress is a major factor in aging. The study's authors plan to investigate the link between oxidative stress and immune defenses further.
A new study analyzed fossil mammal communities and found that the rise of flowering plants, evolved teeth, and dinosaur extinction drove changes in mammalian diversity. Ecological richness was primarily driven by vegetation type, with modern mammals focusing on plant-based diets.
A study analyzes mammalian communities across 98 biomes, finding that vegetation type strongly influences ecological structure. The ecospace of extinct communities overlapped with extant ones, but lacked frugivores and granivores.
Scientists at Scripps Research discovered a life-extension pathway in C. elegans worms that modulates a cannabinoid biological pathway, extending lifespan by up to 45%. The study introduces a powerful method for applying chemical probes to lab animals like worms to discover biology relevant to humans.
A comparative animal study published in JNeurosci found that alligators encode sound location like birds but differently than mammals. The reptile's brain constructs neural maps to chart sound location, a feature observed in close relatives of the alligator, but not in mammals.
Researchers found that forelimb diversity increased around 270 million years ago with the emergence of Permian therapsids. This increase may have allowed for new forelimb functions and enhanced locomotion capabilities.
A new study reveals that a diet rich in birds is the key factor driving influenza A virus exposure in wild African mammals. Herbivores showed low prevalence and diversity, while carnivores had the highest diversity and prevalence.
The study found that Britain's native mammalian carnivores have largely recovered since the 1960s, with otters, badgers, and pine martens showing significant improvements. The species' recovery is attributed to legal protection, conservation, and restoration of habitats.
Researchers at King's College London found that Wnt signalling can be activated to revive a rudimentary dental lamina (RSDL) in mice, allowing for the formation of additional teeth. This breakthrough demonstrates potential for tooth replacement and provides insights into mammalian evolution and trait restoration.
Researchers at the National Institute of Allergy and Infectious Diseases (NIAID) have discovered that flaviviruses reproduce in specific locations within tick salivary gland cultures. This finding could explain why virus transmission occurs so quickly, and may help identify transmission pathways that can be blocked with a countermeasure.
Researchers at Uppsala University discovered a new species of gigantic dicynodont, Lisowicia bojani, in Poland. The species is estimated to be around 4.5 meters long, 2.6 meters high, and weigh 9 tons, making it the largest non-dinosaurian terrestrial tetrapod from the Triassic period.
Harvard researchers create highly-detailed musculoskeletal model of an echidna forelimb to gain insight into its biomechanics and optimize limb leverage for certain movements. The study also reveals the importance of muscle configuration in supporting limb rotation, a key feature of the echidna's sprawling gait.
New research reveals that ligaments hold teeth in place, contradicting previous assumptions. Early dinosaurs like Changchunsaurus parvus had unique tooth replacement methods and wavy enamel.
Research suggests that rising CO2 levels could lead to an increase in mosquito-related diseases, as the climate continues to change. The study found a link between CO2 and mosquito evolution, but also highlights the importance of mammal diversity in driving species richness.
Researchers at the Smithsonian Tropical Research Institute studied Peters' tent-making bats and found that mothers prod their young with forearms, possibly encouraging them to fledge and wean. Bat pups' arms grew faster than the rest of their bodies, allowing them to learn to fly in just a few nights with help from their mothers.
The study examines four decades of research on large mammals in Yellowstone National Park, revealing the influence of wolves on elk calf survival, bear relationships with hunters, and vegetation recovery
The study calculates mammalian phylogenetic diversity loss due to extinctions since the Last Interglacial. Global losses exceed expected random extinctions, with recovery estimated at 3-5 million years for PD lost during this period.
Researchers found a species of blind cavefish lacking an ancient DNA repair system, previously known only in placental mammals. The discovery supports the 'nocturnal bottleneck' theory, suggesting ancestors of modern mammals lived in darkness before dinosaurs.
Researchers confirm lizards enter two distinct sleep states similar to slow-wave and REM sleep in humans and other animals. However, the study reveals differences in brain activity between species, including slower eye movements and unique cerebral patterns in lizard brains.
A large-scale study using camera trap images from hundreds of citizen scientists reveals that suburban areas have a higher variety of mammal species than expected. The researchers found that some mammals, such as coyotes and bobcats, are adapting to urban environments, while others, like bears, are still found in nearby exurban areas.
The Atlantic Forest's biodiversity loss is attributed to 500 years of human disturbance, with more than half of local species assemblages disappearing since the 1500s. Apex predators and large herbivores are among the groups whose numbers have suffered most due to farming, logging, and fires.
A new study led by Harvard University researchers finds that mammal spines have gained new regions during evolution, which enabled them to adapt to different environments. The research challenges the long-held idea that mammal-specific characteristics emerged from a single ancestral blueprint.
Researchers analyzed fossilized backbones and reconstructions to better understand the evolution of mammals' distinct spinal regions. The study found that forelimb reorganization played a crucial role in driving regionalization across the spine, leading to the varied forms of modern mammals.
Researchers found that mammal backbones gained distinct regions during evolution, enabling adaptation to various lifestyles such as running, flying, and digging. The study analyzed fossil records and living animals' vertebrae, challenging the notion of specialization in early land animals.
Researchers discovered that sea otters rely on the sensitivity of their paws and whiskers to hunt for food, distinguishing between grooves as small as 2mm with remarkable accuracy. This unique ability enables them to quickly locate prey in cloudy Monterey Bay waters.
A new study reveals that getting smaller was crucial for mammalian evolution, reducing jaw stresses while maintaining feeding power. The research used CT scans and computer simulations to analyze fossil skulls and lower jaws, providing a new explanation for the mammalian jaw's unique structure.
Researchers found that dominant meerkat breeders exhibit accelerated aging due to the physical and social stresses of leadership, yet they consistently outlive their subordinate counterparts. This study suggests that being a dominant breeder is key to longevity in meerkats.
A newly discovered mammal fossil contains fossils of 38 babies, providing insight into the evolution of mammals' reproductive strategies. The discovery suggests that a key development in mammalian evolution was trading brood power for brain power.
Researchers mapped the evolutionary journey of animal guts to defend against microbial attack. They discovered that tunicates, a simple animal related to vertebrates, had an intermediate gut lining with both chitin and mucous coexisting. This finding suggests a missing link between invertebrate and mammalian gut defenses.
A 19-year analysis of forest ecology reveals that high rodent densities and low predator populations contribute to increased Lyme disease risk. Acorn production also plays a significant role, as high abundance boosts rodent numbers and increases infected nymphal tick populations.
The article examines 12 leporid species introduced by humans, highlighting their effects on ecosystems, including providing food resources for predators and competing with native herbivores. Conservation biologists must carefully consider these impacts when planning management strategies.
A new study reveals human activity is driving mammals to adopt nightlife, changing behavior and physiology; high levels of disturbance lead to increased nocturnal activity by a factor of 1.36.
A comprehensive survey of mammalian microbiomes found humans to have a significantly lower diversity of skin microorganisms compared to other mammals. This difference may be attributed to modern hygiene practices, habitat, and co-evolution between host and skin microbial communities.
A nearly 130-million-year-old fossilized skull found in Utah is evidence that the super-continental split occurred more recently than previously thought. The study suggests that early mammal relatives migrated across several continents during the Early Cretaceous period, occupying various niches similar to modern mammals.
Research by Ingo Titze and Anil Palaparthi found that animals' high radiation efficiency is due to wide mouths, high frequencies, and body acoustical reflecting chambers. Humans lack these traits, limiting our ability to make long-range calls like animals do. The study aims to improve human call efficiency for emergency situations.
A global biomass census yields 550 Gt C, with land biomass surpassing marine by two orders of magnitude. Human activities have led to significant reductions in wild mammal, fish, and plant biomass.
Researchers used functional MRI to study Nile crocodiles and found that complex stimuli like classical music trigger activation patterns in the brain. This suggests that fundamental neuronal processing mechanisms of sensory stimuli formed at an early evolutionary stage.
A previously undescribed species of Cretaceous period island-dwelling mammal has been discovered in present-day Romania, exhibiting a domed skull and an extremely small brain relative to body size. The mammal's adaptability to island environments developed early in the evolutionary history of mammals.
A new study links human activities to a massive extinction event that wiped out large mammals globally. The research suggests that size-biased extinctions started at least 125,000 years ago in Africa and spread to other continents as humans migrated, leaving only smaller mammals behind.
A new study by Felisa A. Smith et al. found a substantial bias in mammal extinction during human dispersal periods, with species that went extinct being two to three times bigger than surviving mammals. This trend is evident globally and reflects hominin-mammal interactions.
A study of aquatic mammal body size evolution found that environments constrain body size more than terrestrial habitats do. The analysis suggested that thermoregulation and metabolism force aquatic mammals to grow larger than their terrestrial counterparts.
Researchers sequenced the genomes of 57 platypuses across Eastern Australia and Tasmania, establishing a family history and kinship in unprecedented detail. The study provides insights into population structure, diversity, and evolutionary forces at work, shedding light on the conservation challenges facing this unique species.
New research reveals that fish was a dominant source of protein in the Stone Age diet, with 50-60% of protein intake coming from marine sources. The study uses stable isotopes to analyze human bones and finds that fishing was surprisingly common, even in areas where land mammals were scarce.
The Hispaniolan solenodon's genome sequence reveals it survived the dinosaurs and provides crucial insights for conservation. The data supports subspecies split within the population, requiring independent breeding strategies to ensure their survival.
A new study reveals that primitive air-breathing fish, such as the South American lungfish, exhibit similar mechanisms controlling the heart as mammals. These mechanisms include a periodic breathing pattern and respiratory sinus arrhythmia (RSA), which enables the fish to maximize oxygen uptake during air-breathing bouts.
Researchers found that ancient proteins in insect and mammal brains share common ancestry as regulators of body temperature rhythms crucial to metabolism and sleep. This discovery may lead to new treatments for circadian clock diseases and sleep problems.
A recent study published in the Journal of Mammalogy reveals that over 1000 new species of mammals have been described globally during the last dozen years. This rate of species discovery parallels that seen in global amphibians, driven by advances in DNA analysis methods and field exploration.
Researchers analyzed over 270 million years of data to find that mammals and birds are better equipped to evolve and adapt to a changing climate. They have the ability to regulate their body temperature, allowing them to thrive in colder temperatures.
Researchers found that mammals move up to 2-3 times less in human-modified areas compared to natural habitats. This study, led by Penn State researcher Duane Diefenbach, analyzed movement data from 57 mammal species across the globe.
A global study by researchers at Senckenberg Nature Research Society and Goethe University Frankfurt found that mammals cover half to one-third of their usual distances in human-modified areas. This reduction affects ecosystem functions, including nutrient transport and species interactions.
A study found that human footprint reduces mammalian movement by two to three times, with no geographic or size-based exceptions. This affects ecosystem functions like nutrient transport and food web interactions, highlighting the need for further research on critical thresholds in human land use.
New study finds that mammal movements are reduced by up to three-fold in areas with high human activity, affecting not only individual animals but also ecosystems. Movement distances vary by species and resource availability, suggesting a complex interplay between humans and wildlife.
A global study finds human alterations to natural habitats reduce mammal travel distances by at least half, with some species relying on humans for resources. This disruption can impact ecosystems and food webs.
Research found that dingo removal decreased abundance of small mammals, while fox removal increased ground-dwelling and arboreal mammal populations. The study also revealed interactions between predators and their effects on cat populations.