Articles tagged with Mammals
A new mechanism of neuronal conduction of excitation has been discovered, independent of action potentials, using ceramide production. This finding opens up new perspectives for research and breaks away from the classic concept of neuronal functioning.
Despite being bastions of biodiversity conservation, African national parks are losing species at an alarming rate. The decline is attributed primarily to anthropogenic causes such as poaching and human encroachment, leading to the loss of large mammal populations.
Nectar-feeding bats have the highest metabolic costs among mammals, requiring them to fuel up directly from sugary nectars. This direct metabolism method saves energy by avoiding storage conversions, but also makes them highly vulnerable to environmental changes affecting their food supply.
A team of researchers created an interactive 'supermap' using Google Earth technology to visualize the mutations and spread of the avian flu around the globe. The map allowed users to analyze movements and changes in genetic blueprints of known avian flu sub-strains, providing insights into viral spread and potential future outbreaks.
Researchers developed a robust time estimation method, resolving discrepancies between paleontological and molecular studies on placental mammal evolution. The revised estimate places the root of placental mammals at 84 million years ago, aligning with fossil records and traditional morphological views.
A new study reveals that the mass extinction event that wiped out dinosaurs did not prompt the rapid diversification of modern mammal species. Instead, these early mammals evolved and radiated around 10 million years after the dinosaurs' demise, driven by a sudden increase in global temperature.
A comprehensive tree of mammalian evolution puts major diversifications well after dinosaur die-off, casting doubt on their impact. The team constructed a complete evolutionary tree using molecular data and fossil evidence, finding that diversification didn't take off until the Eocene epoch, about 56 to 34 million years ago.
Research reveals that birds can live with higher doses of sex-related genes due to ineffective dosage compensation. This challenges current thinking about the role and mechanisms of dosage compensation in species with heteromorphic sex chromosomes.
A recent study published in Nature documents the largest climate change in North America over the past 65 million years, with fossilized teeth revealing a temperature drop of nearly 15 degrees Fahrenheit. The Eocene-to-Oligocene transition saw massive changes in ocean currents and life extinctions.
A recent study by Stanford University researchers found that large herbivorous mammals can have a significant impact on ecosystem health. In an experiment in central Kenya, the removal of cattle, elephants, and zebras led to an increase in the populations of trees, beetles, lizards, and other species.
A Mayo Clinic researcher has identified a target site in malaria-carrying mosquitoes that could be used to develop pesticides toxic to the Anopheles gambiae mosquito and other species. This finding could lead to a safer and more effective method to control mosquito-borne diseases like malaria.
A Mayo Clinic researcher has identified a target site in malaria-carrying mosquitoes that could be used to develop toxic pesticides. The residues are found in three mosquito species and the German cockroach, but not in mammals.
A comprehensive worldwide map of mammals, birds, and amphibians shows that endangered species from different groups don't inhabit the same areas, contradicting conservationists' assumptions. This discovery has significant implications for conservation planning and decision-making.
Early mammals' eyes have only one version of the photoreceptor gene that detects light, unlike birds, fish, and amphibians with two versions. This suggests they may have been nocturnal creatures.
Scientists discovered a unique evolutionary link between primitive B cells in fish and the adaptive immune response in humans. In fish, B cells participate in phagocytosis, attacking and eating foreign particles; this behavior is unexpected in mammals. The findings may lead to novel roles of B cells in mammals and improved fish vaccines.
A unique evolutionary link has been found between the immune systems of fish and mammals, with primitive B cells in fish playing a key role in phagocytosis. This discovery could lead to new strategies for developing effective fish vaccines and offers insights into the evolution and function of immune cells.
A recent study confirms the 'island rule,' where small animals evolve into oversized versions of their continental counterparts, while large animals shrink. Island species exhibit accelerated evolutionary changes over short time frames, with a faster rate of evolution than mainland species.
A new University of Florida study suggests that large dinosaurs, such as Sauroposeidon proteles, had body temperatures close to 48 degrees Celsius, comparable to modern-day birds and mammals. This discovery challenges the long-held assumption that dinosaurs were cold-blooded reptiles.
The most recent census found that efforts to protect the park's wildlife are reversing the trend of decline, with elephant populations increasing to 340 individuals. The park's large mammal populations have also increased, including buffalo and Uganda kob.
Researchers discovered high levels of melatonin in Nebbolo, Merlot, Cabernet Savignon, Sangiovesse, and Croatina grapes. The study suggests that melatonin content can be enhanced by treating vines with a plant vaccine Benzothiadiazole.
Researchers have discovered a new class of small RNAs called piRNAs in the mouse germline, which are bigger than previously described small RNAs. These novel small RNAs are thought to play a role in spermatogenesis and have unique features that distinguish them from other types of small RNAs.
Researchers are studying salamanders and MRL mice to identify the types of cells, molecular signals, genes, and cellular scaffolding required for regenerative cell growth. They hope to develop a blueprint for regenerative growth, which could help overcome the formation of scar tissue in humans.
A new gene, Lazaro, has been discovered to reduce retinal degeneration in fruit flies by enhancing the production of diacylglycerol, a key player in controlling TRP channels. This discovery may have implications for understanding sensory signaling in mammals.
Researchers found that elevating perceived sexual competition in male house mice led to increased vigorous thrusting and premature ejaculation during copulation. Males were nearly twice as likely to ejaculate on a second occasion when a rival male was present.
Researchers found that a protein called Cryptochrome helps regulate the biological clock in fruit flies, similar to its role in mammals. The study provides new insights into the human biological clock and its relationship to sleep-wake cycles and overall health.
Researchers discovered a new brain hormone GnIH that directly inhibits the action of gonadotropin-releasing hormone (GnRH), stimulating the reproductive system. This finding suggests that GnIH plays a similar role in humans and other mammals, offering potential new treatments for infertility and precocious puberty.
A study found that the Hh pathway in insects determines whether adult stem cells are fated for fat or bone, with implications for treating osteoporosis, diabetes, and obesity. The researchers also discovered that drugs targeting this pathway could potentially build stronger bones while reducing fat.
Researchers found that electrical synapses in the thalamic reticular nucleus can undergo long-term changes, influencing brain rhythms and behavioral states. The study provides new insights into neural plasticity and its role in regulating sleep, wakefulness, and other critical brain functions.
Researchers discovered that bacteria and elephants consume energy at a similar rate per unit mass, regardless of their body size. This finding suggests that living organisms can overcome physical limitations by adapting to their own biochemical characteristics.
The study found that muskoxes were genetically more diverse before the Pleistocene/Holocene transition, with extinct haplotypes only found in northern Asia. The authors suggest that reduced genetic variability may have contributed to the extinction of other great mammals like mammoths.
Research suggests that increased oxygen levels in Earth's atmosphere led to the emergence of large placental mammals, including massive sloths and saber-toothed cats. The study, published in Science journal, uses deep-sea core samples to track changes in oxygen content over 205 million years.
The mouse genome is more complex than expected, with over 60% of mRNAs not encoding proteins. The discovery challenges the traditional view that genes contain specific protein blueprints.
The discovery of avian flu in a new family of mammals highlights the possibility that the virus may be capable of infecting other mammal species. Critically endangered civet cats in Vietnam are at risk due to lack of screening, prompting concerns for biodiversity hotspots.
Researchers have identified new amphibian species through genetic analysis and bioacoustic tools, contrary to the assumption that taxonomic inflation is driving species discoveries. This finding underscores the importance of continued exploration and conservation efforts in this endangered vertebrate group.
The study identified key factors contributing to large mammal extinction, including biological disadvantages and human impact. Smaller mammals are more vulnerable due to limited distribution sizes and exposure to humans, while larger animals face additional challenges such as long gestation periods and late weaning ages.
Researchers found that chickadees produce two distinct alarm signals, warning of predator size and threat level. The birds assess risk based on body size, with larger raptors posing greater danger.
A study published in Science identifies the master gene grainyhead as essential for wound repair in both fruit flies and mice. The researchers found that grainyhead is required to activate genes involved in cuticle repair, which then regenerate injured patches of skin.
A study found that an ancient enzyme, GCN2 kinase, plays a crucial role in guiding healthy eating behavior in mammals. The enzyme detects changes in blood amino acid levels and triggers a behavioral response to limit consumption of imbalanced food.
Researchers found evidence of the first elephant shrews' presence in North America, suggesting a greater animal migration than previously thought. This discovery has significant implications for our understanding of mammalian evolution and the history of continental breakups.
A new study suggests that ingestion of afterbirth may modify specific opioid-receptor systems in the brain, facilitating the onset of maternal behavior. The research, led by UB professor Mark Kristal, aims to determine how endogenous opioid activation during pregnancy and delivery influences maternal behavior.
A research team has published a paper in Science that uses molecular biology to fill gaps in the evolutionary history of bats. The study reveals that megabats originated from four major lineages of microbats, which emerged around 52-50 million years ago.
Researchers propose a new naming system for bird neurosystems, revealing similarities to mammalian brains. The revised nomenclature reflects recent discoveries in neural processing and behavior, highlighting the cognitive abilities of birds comparable to those of mammals.
A research team has published a paper in Science magazine that uses molecular biology to illuminate the evolutionary history of bats. The study reveals that large fruit-eating bats (megabats) emerged from four major lineages of smaller, night-flying bats (microbats), with the latter originating around 52-50 million years ago.
Researchers found sharks can detect geomagnetic field changes, which may aid navigation. This discovery builds upon previous studies on bird navigation.
The newly published chicken genomic sequence provides significant information on vertebrate evolution, revealing a clade of at least 9,600 avian species. The analysis also sheds light on the unusual genomic organization of chickens, including large variability in chromosome size and germline mutations.
Penn researchers successfully inactivated the Foxp4 binding protein, allowing bilateral cardiac primordia to fuse into single tubes. This resulted in four-chambered hearts developing with most aspects of advanced heart development, challenging current understanding of congenital heart disease.
A recent study by a University of Nevada researcher suggests that glucose levels in female mammals may influence the sex of their offspring, challenging a long-standing hypothesis in evolutionary biology. The study's findings have significant implications for wildlife conservation and agriculture production.
The Ecological Society of America symposium explores ecological recovery after the 1980 Mount St. Helens eruption, revealing remarkable resilience in some species and dramatic transformation of Spirit Lake. Researchers discuss the importance of chance events, life history characteristics, and timing in ecological recovery.
Researchers developed a mathematical model that accurately reproduces gypsy moth population outbreaks, combining host-pathogen and predator dynamics. The model resolves the irregular timing of outbreaks and accounts for spatial synchrony, paving the way for applications to other forest insects and small mammals.
Researchers at Duke University Medical Center found that flies have distinct combinations of bitter-sensitive nerve cells on their tongue, allowing them to discern among different bitter tastes. This unique ability might enable flies to select the best food item among multiple suboptimal choices.
The study established four principles of olfactory system development: without sensory activity there is no full maturation, a sensitive period influences organization maturation, sensitive periods occur at different times for different receptors, and glomeruli may be innervated by multiple nerves during early development.
A study by University of Washington researchers exposes the existence of two distinct circadian clocks within the mammalian brain, one tied to an internal schedule and another influenced by external light-dark cycles. The discovery sheds new light on how artificial day-night cycles can disrupt physiological rhythms in mammals.
A team of researchers found that certain mammals in the Arctic, including rodents, retained a regular sleep-wake cycle despite 82 days of continuous daylight or darkness. The study suggests that the animals may have used external environmental clues to adapt their biological clocks.
A recent analysis of 11,633 species published in Nature found that more than 300 critically endangered species are completely unprotected. The study emphasizes the need for a major shift in conservation strategies to prevent large-scale species extinctions over the next few decades.
A new discovery of fossil mammals in Ethiopia's highlands sheds light on the evolution of African mammals during a long-standing gap in scientists' understanding. The findings, reported in Nature, show that mammals continued to evolve and produce new species on the isolated continent of Afro-Arabia.
Researchers found naked mole-rats naturally lack Substance P, a neurotransmitter that sends pain signals to the central nervous system. Introducing Substance P restored pain signaling in these animals, sparking hope for new therapies to treat fibromyalgia.
Researchers at the University of Illinois discovered that the timeless gene is essential for regulating the 24-hour circadian rhythm in mammals. Blocking its functional ability disrupts the clock's activity and leads to an uncoupling effect, where other clock genes are no longer able to function properly.
A new study analyzing 11,000 mammal, amphibian and bird species reveals major gaps in the global protected area system, placing over 700 species at risk of extinction. The analysis highlights urgent conservation priorities for tropical areas, islands, and specific endangered species.
MaNIS improves access to natural history specimen data, facilitating conservation hotspot identification, ecosystem change monitoring, disease tracking, invasive species management, and biodiversity studies. The distributed database network provides researchers with millions of specimens' information online.
A recent study by Ohio State University anthropologist Jeffrey McKee predicts that the United States will face a significant threat to global biodiversity within 50 years, with at least 10 additional species added to the threatened list. The prediction is based on a model that separates human population growth from environmental impact...