Articles tagged with Mammals
Despite extensive research, fossil pollen from Central and West Africa provides no definitive evidence for communities of rainforest trees at the beginning of the Cenozoic. Paleobotanist Bonnie F. Jacobs and her colleagues have mapped out the limited fossil record, which consists of only 82 sites, most dating back to 50 million years ago.
Scientists at University of Cambridge discover how sloths evolved their unique neck skeleton, finding early bone formation in distal neck vertebrae. The study reveals that sloth's bottom neck vertebrae are developmentally similar to ribcage vertebrae of other mammals.
Researchers found that desert night lizards stay with their parents and siblings for several years after birth, forming family groups. The study suggests that viviparity provides the opportunity for prolonged interaction between mothers and offspring, predisposing animals to form cooperative behaviors.
Mammoths, reindeer and woolly rhinos found in Iberia during cold climate periods, coinciding with global cooling in Greenland. The species' presence indicates a biological crisis as temperatures warmed up, leading to habitat loss.
The discovery of fossilized bones with cut marks in Ethiopia pushes the timeline of stone tool use and meat consumption back by nearly a million years. The evidence suggests that early human ancestors, such as Australopithecus afarensis, used stone tools to butcher meat from large mammals.
Scientists report the discovery of a unique Cretaceous creature with mammal-like teeth, challenging traditional views of ancient animal life. The new species, Pakasuchus, was found in Tanzania and is believed to have been a land-dwelling, insect-eating creature that thrived during the middle Cretaceous period.
A study of orangutans found they used remarkably low energy levels, similar to those of sloths. This adaptation may be an evolutionary response to food shortages in their native rainforests, where ripe fruit is unpredictable and scarce.
Large mammal populations in African national parks have declined by up to 59% since 1970, with some species experiencing dramatic decreases. Despite this, improved management and conservation efforts in southern Africa offer a glimmer of hope for the long-term survival of these iconic species.
Researchers at UC San Diego discovered that the brains of humans and chickens share comparable regions for analyzing auditory inputs. The study found laminated layers of cells linked by narrow columns in both species, indicating that complex cognitive functions may have evolved from ancient vertebrates.
At high altitudes, mountain mice use more carbohydrates than fat to fuel exercise, saving oxygen and increasing energy yield. This adaptation allows them to thrive in low-oxygen environments.
Researchers discovered a novel protein complex that regulates around 4000 genes in Drosophila, with implications for human biology. The Non-Specific Lethal (NSL) complex helps MOF bind to promoters and determine gene expression in both sexes.
A new global approach reveals that climate change played a major role in causing mass extinction of mammals in the late quaternary era. The study shows that continents with larger 'climate footprints' experienced more extinctions, supporting the idea that past climate changes contributed to global extinctions.
A new study by North Carolina State University researchers links the number of diseases in a region to its climate and biodiversity, with hot, wet climates having more pathogens. The prevalence of diseases, however, is influenced by health-care spending, particularly in regions with low spending.
The study provides a comprehensive atlas of transcription factor combinations, indicating which factors can combine to determine cell fate. The researchers identified nearly 1,000 different pairs of TF proteins that can be wired together, representing the blueprint of all possible combinations that direct gene expression in mammals.
Research shows that eye position has no effect on speed and agility in mammals, with some species able to travel as fast as cheetahs without blurring vision. The vestibulo-ocular reflex is adapted through muscle switching, allowing the brain to cope with changing eye positions.
Research by Tel Aviv University's Prof. Yoram Yom-Tov reveals that animals at higher latitudes are adapting to rising temperatures by altering their diets and body sizes. This adaptation is seen in birds getting smaller and mammals getting bigger, allowing them to cope with warmer temperatures.
Researchers have identified a dozen protein building blocks in the venom of male platypuses, which cause excruciating pain. The study's findings suggest that one of these substances, Heptapeptide 1, triggers pain by interacting with nerve cell receptors.
Prof. Michael Gurevitz's research isolates genetic sequences for neurotoxins in scorpion venom and develops methods to produce and manipulate toxins for restricted toxicity in certain insects or mammals. This work paves the way for a new, ecologically sound pest control method.
John Flynn, Frick Curator of Fossil Mammals and Professor at the American Museum of Natural History, has been awarded the distinction of Fellow by the American Association for the Advancement of Science (AAAS). Dr. Flynn's research focuses on vertebrate paleontology, especially carnivore evolution and faunal succession in South America.
Researchers analyzed mammal diversity data from 30 million years ago and 500 years ago, finding a significant loss of species following human arrival in North America. The study suggests humans are causing another mass extinction event, with potential conservation efforts able to stem the tide.
A new fossil species, Kombuisia antarctica, discovered in Antarctica, reveals that some land animals may have survived the end-Permian extinction by living in cooler climates. The discovery fills a gap in the fossil record and contributes to understanding of vertebrate survival during this mass extinction event.
Researchers found female mice created from two mothers but no father lived significantly longer than normal mice, living up to a third longer on average. The findings suggest that sperm genes may have a detrimental effect on lifespan in mammals.
Veterinary scientists harnessing 'barcodes' of microbes to develop a single, effective vaccine for all mammals. Tiny variations in TLRs could be key to adapting vaccines across species.
The study found that mammals are protected from the majority of fungal pathogens due to their elevated body temperature, which is too high for most fungi to survive. This theory could help explain why mammals rose to dominance after the dinosaur extinction event.
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.
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.
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.
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.