Articles tagged with Mammals
A new study by Indiana University researchers found a common link between bird flocks, breast milk, and trust, regulated by neurochemicals oxytocin and mesotocin. Blocking mesotocin in female zebra finches reduced social preferences, while administering it increased social behavior.
A study found substantial changes in rodent size and shape over the past century, tied to human population density and climate change. Rodents from around the world, including Channel Island deer mice and white-footed mice, exhibited significant anatomic changes, with increases and decreases in 15 traits measured.
A study reveals that the lesser short-tailed bat's walking ability evolved in an ancient Australian lineage, contradicting previous assumptions. The bat's unique adaptations, such as adhesive grooves and extra talons, have advantages only in specific circumstances, not due to competition from other mammals.
Research finds that mice fed sunflower oil (n-6 polyunsaturated fatty acids) run faster than those on linseed oil (n-3 fatty acids), achieving a 6.3% boost in sprint speed. This effect is significant for small mammals, such as mice and their predators.
Researchers at the University of California, Berkeley, have found a critical piece in the puzzle about how stress causes sexual dysfunction and infertility. Stress hormones, such as glucocorticoids like cortisol, inhibit the body's main sex hormone GnRH, while also increasing another hormone GnIH, which directly inhibits GnRH.
Scientists successfully constructed a non-native pathway in mice that increased fatty acid metabolism and resulted in resistance to diet-induced obesity. The glyoxylate shunt, unique to plants and bacteria, was introduced into the mitochondria of liver cells to create an additional pathway for converting fatty acid into carbon dioxide.
Researchers found that interglacial warming resulted in dramatic changes to the diets of animal groups, with some becoming mixed feeders that grazed on grasses. The study highlights the importance of the fossil record in understanding long-term ecological responses to climate change.
Researchers analyzed fossil teeth from two sites in Florida representing different climates and found dramatic changes in mammalian diets during interglacial periods. The study suggests that climate-driven environmental changes can lead to shifts in animal groups' dietary niches, complicating future modeling of mammal distributions.
A major international study by the FANTOM consortium has found that genes are not controlled by 'master regulators' as previously thought. Instead, a more subtle and coordinated approach is needed for cellular differentiation and cancer development.
Researchers found that nocturnal mammals have an inverted chromatin arrangement in their rod nuclei, which acts as micro-lenses to focus light. This unique organization enhances night vision and provides new insights into the evolution of mammalian retinas.
Researchers have discovered that nocturnal mammals' rod cell nuclei are inverted, allowing for reduced light scatter and enhanced low-light vision. This unusual organization enables these animals to perceive light as much as a millionth of daylight's intensity.
Research suggests that female mammals use olfactory cues to select genetically dissimilar mates for healthier offspring. Mammals may prefer males with unique scents over those with parasites or dominant traits. This line of research reveals the importance of mammalian mate choice, challenging traditional assumptions.
Scientists propose that rapid sea level rises over the past 5 million years led to habitat compression, causing species extinction locally. A study of 325 mammal species mapped their ranges across the peninsula, revealing a 600-kilometer gap with 30% fewer species than expected.
Researchers uncover how opposing genetic forces determine the correct pattern of tooth formation in mammals, revealing a potential pathway for tooth regeneration and combating birth defects. The study's findings suggest that careful regulation of competing pro- and anti-tooth initiation signals controls the sequence of tooth development.
Genetic research reveals black rats carried a pathogenic protozoan that exterminated two endemic species on Christmas Island. The study is the first to demonstrate extinction in a mammal due to disease, contradicting most scientists' view of pathogens' effect on species.
The Global Mammal Assessment project has identified seven Texas mammal species as threatened, including the Mexican long-tongued bat and desert pocket gopher. The IUCN Red List reveals that one in four mammalian species are currently at risk of extinction.
Research by Queen Mary University of London scientists found that some bat species' echolocation genes are similar to those of fruit bats, indicating possible independent evolution of the trait. This suggests that echolocation may not be a single evolutionary event but rather an example of convergent evolution.
Researchers studied the Prestin gene in echolocating bats and fruit bats, finding similarities in distantly related species. This suggests that echolocation has evolved more than once in bats, defying conventional wisdom on evolutionary relationships.
Researchers found that higher-ranking males produced groans with lower minimum fundamental frequencies and to a lesser extent, with lower formant dispersion. Dominance status was the factor most strongly related to mating success, with higher-ranking males having higher mating success.
A study published in PLOS Biology found that magpies exhibit self-recognition in a mirror test, recognizing their own image as themselves. This discovery indicates that non-mammalian species can engage in self-recognition behavior, challenging the assumption that advanced cognition is exclusive to mammals.
A new study using ecological niche modeling found that small mammals on mountaintops in the Great Basin are not as isolated as previously believed. The research used climate data to 'backcast' species distributions at the height of the last ice age, finding most species lived at lower elevations and had larger ranges.
Researchers at UCSC have identified a novel type of gene regulation in mammals involving hammerhead ribozymes, which control the activity of important immune response and bone metabolism genes. The discovery challenges previous views on gene expression and suggests a more versatile role for RNA molecules.
Researchers from the University of Bristol found that mammals have two decision-making systems: a fast-but-inaccurate sub-cortical brain and a slow-but-accurate outer cortex. The study suggests that the older system may still be beneficial in modern situations, potentially preventing atrophy and smaller brains in future humans.
The platypus genome sequence published by UK researchers reveals a mix of mammalian, bird-like and reptilian features in the species' genetic blueprint. The analysis found that platypus venom is a cocktail of proteins originally with different functions, similar to those in reptile venom.
A study by Eric Post at Penn State has found that global warming is causing trophic mismatch in West Greenland's caribou population, where plant growth is advancing ahead of animal births. This phenomenon, linked to climate change, may hinder the species' ability to adapt and persist.
A recent discovery of the greater white-toothed shrew in Ireland raises concerns about ecological impact and control. The introduction is believed to have occurred recently, with seven individuals trapped in four locations in Tipperary, marking a rare event for the country.
A new study found that young fire ant workers are four times more likely to survive aggressive attacks by pretending to be dead. Sustained movement is necessary to trigger a physical attack. Feigning death allows these young workers to contribute to brood care and colony growth.
Researchers found that pigeons increase slow-wave sleep to recover from sleep loss, mirroring human brain function. This discovery sheds light on the role of sleep in animals and may provide insights into human sleep patterns.
Researchers found that bats use magnetite as an 'internal compass' to help them navigate. The study involved giving Big Brown bats magnetic pulses and observing their behavior.
A recent study by Vanderbilt University reveals that shrews, despite their small size, employ highly developed hunting strategies. The researchers discovered that these tiny mammals can detect water movements, identify prey shapes using their whiskers, and utilize their sense of smell underwater.
The newly discovered grey-faced sengi (Rhynchocyon udzungwensis) is a large, rare species found only in two high-altitude forest blocks in Tanzania's Udzungwa Mountains. Its unique features include a distinctive grey face and jet-black lower rump, highlighting the region's exceptional biodiversity.
Researchers propose that pika leptin's adaptive functional evolution may be driven by cold environmental stress, not hypoxia. This discovery has significant implications for understanding small mammals' adaptation to extreme environments and identifying new candidate therapies for human diseases like obesity and diabetes.
A new study by UC Berkeley scientists reveals that dinosaurs experienced rapid growth spurs and reached sexual maturity near the end of this phase, well before reaching maximum body size. This finding suggests that dinosaurs were born precocious and suffered high adult mortality, making early sexual maturity necessary for survival.
Researchers have identified potential habitats in the central and northern Sierra Nevada Mountains for reintroducing California fishers, a rare and elusive carnivore. The study suggests caution in implementing reintroduction efforts due to limited connectivity and distance from existing populations.
A study reveals that elephants, giraffes, and other large plant-eaters spur Acacia trees to hire ants as bodyguards, but without them, the trees suffer. The research highlights how people's impacts on ecosystems can cascade down unexpected paths.
A team of scientists discovered a fossilized remains of an extinct tank-like mammal, Parapropalaehoplophorus septentrionalis, which is a primitive relative of modern armadillos. The animal lived in the Andes around 18 million years ago and weighed approximately 200 pounds.
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 toxic pesticides. The residues are found in three mosquito species and the German cockroach, but not in mammals.
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 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.