Mongoose sentinels respond flexibly to threats
2014-11-13
(Press-News.org) Just as soldiers on sentry duty constantly adjust their behaviour to match the current threat level, dwarf mongoose sentinels exhibit flexible decision-making in relation to predation risk, new research from the University of Bristol has shown.
Biologists Julie Kern and Dr Andy Radford found that decisions about when to go on duty, what position to adopt and how long to remain on post were all affected by information about the likelihood of danger. Sentinels altered their behaviour depending on both environmental conditions, such as wind speed and social signals, such as alarm calls.
The new study, published in Animal Behaviour, shows that mongooses are capable of real-time behavioural plasticity in response to both direct and indirect indicators of predation risk.
Julie Kern, lead author and PhD student, said: "Our work demonstrates how sentinel behaviour is adjusted flexibly with regard to information presented on various time scales, highlighting the complexity of animal decision-making processes."
The work was conducted on a wild population of dwarf mongooses that are individually marked and habituated to the close presence of observers.
Dr Andy Radford, co-author and Reader in Behavioural Ecology in the School of Biological Sciences, said: "Being able to walk within a few feet of these animals as they go about their daily routines allows detailed investigations into behaviour in natural conditions."
Foraging group members rely on sentinels to warn them of approaching danger, but also to inform them of the current level of threat. That way they can optimise their own behaviour in terms of time spent foraging versus being vigilant.
Dwarf mongooses, Africa's smallest carnivore, live in close-knit family groups of between 5 and 20 individuals. Each group spends the night in a safe retreat, such as a termite mound, and emerges to spend the day foraging for buried insects and lizards. They are vulnerable to a wide range of predators, including snakes, cats and birds of prey.
INFORMATION:
Paper
'Sentinel dwarf mongooses (Helogale parvula) exhibit flexible decision-making in Relation to predation risk' by Julie M Kern and Andrew N Radford in Animal Behaviour.
ELSE PRESS RELEASES FROM THIS DATE:
2014-11-13
Human communication has long been associated with an unlikely companion, the homing pigeon; but how these pigeons find their way home is still largely a mystery. 'There is widespread agreement that pigeons are able to determine and maintain flight (compass) directions based on solar and magnetic cues,' says Hans-Peter Lipp from the University of Zurich, Switzerland, and Kwazulu-Natal University, South Africa. However, another piece of the puzzle - how the bird determines its position, known as the map sense - was unclear. Dissatisfied with the current theories - that pigeons ...
2014-11-13
SAN FRANCISCO, Nov. 12, 2014 -- Porcelain crabs can adapt to a warming climate but will not have energy for much else beyond basic survival, according to new research published today from San Francisco State University.
The findings have grim long-term implications for intertidal zone crabs as well as the myriad species that depend on them, and could be an indicator of how other intertidal organisms may respond to a rapidly changing climate.
The study is detailed in an article published in the Journal of Experimental Biology and is the first to explore intertidal zone ...
2014-11-13
(TORONTO, Canada - Nov. 13, 2014) - Prostate cancer researchers have developed a genetic test to identify which men are at highest risk for their prostate cancer to come back after localized treatment with surgery or radiotherapy.
The findings are published online today in Lancet Oncology. Study co-leads Dr. Robert Bristow, a clinician-scientist at Princess Margaret Cancer Centre, and Dr. Paul Boutros, an investigator at the Ontario Institute for Cancer Research, report that the gene test provides a much-needed quick and accurate tool to determine with greater precision ...
2014-11-13
Rare mutations that shut down a single gene are linked to lower cholesterol levels and a 50 percent reduction in the risk of heart attack, according to new research from Washington University School of Medicine in St. Louis, the Broad Institute at Massachusetts Institute of Technology and Harvard, and other institutions.
The gene, called NPC1L1, is of interest because it is the target of the drug ezetimibe, often prescribed to lower cholesterol.
The study appears Nov. 12 in The New England Journal of Medicine.
Everyone inherits two copies of most genes -- one copy ...
2014-11-13
A study in which more than 43,000 children were evaluated for head trauma offers an unprecedented picture of how children most frequently suffer head injuries, report physicians at Washington University School of Medicine in St. Louis and the University of California, Davis, School of Medicine.
The findings also indicate how often such incidents result in significant brain injuries, computerized tomography (CT) scans to assess head injuries, and neurosurgery to treat them.
In children ages 12 and younger, falls were the most common cause of head injuries. In children ...
2014-11-13
Philadelphia, PA, November 12, 2014 - Critical care is defined by life-threatening conditions, which require close evaluation, monitoring, and treatment by appropriately trained health professionals. Cardiovascular care bears these same requirements. In fact, cardiovascular disease will soon surpass even human immunodeficiency virus (HIV) as the leading cause of mortality in Sub-Saharan Africa. In the latest issue of Global Heart, researchers discuss the challenges of delivering critical care in resource-limited countries.
According to Guest Editors Vanessa Kerry, MD, ...
2014-11-13
What time is it? The answer, no matter what your initial reference may be -- a wristwatch, a smartphone, or an alarm clock -- will always trace back to the atomic clock.
The international standard for time is set by atomic clocks -- room-sized apparatuses that keep time by measuring the natural vibration of atoms in a vacuum. The frequency of atomic vibrations determines the length of one second -- information that is beamed up to GPS satellites, which stream the data to ground receivers all over the world, synchronizing cellular and cable networks, power grids, and ...
2014-11-13
(Santa Barbara, California) -- The world is gaining weight and becoming less healthy, and global dietary choices are harming the environment.
Those are among the findings of a paper co-authored by David Tilman, a professor in the Bren School of Environmental Science & Management, and Michael Clark, a graduate student at the University of Minnesota, where Tilman also is a professor. In "Global Diets Link Environmental Sustainability and Human Health," published today in the journal Nature, the researchers find that rising incomes and urbanization around the world are ...
2014-11-12
MINNEAPOLIS - Taking vitamin B12 and folic acid supplements may not reduce the risk of memory and thinking problems after all, according to a new study published in the November 12, 2014, online issue of Neurology®, the medical journal of the American Academy of Neurology. The study is one of the largest to date to test long-term use of supplements and thinking and memory skills.
The study involved people with high blood levels of homocysteine, an amino acid. High levels of homocysteine have been linked to memory loss and Alzheimer's disease.
"Since homocysteine ...
2014-11-12
A protein that may partly explain why human brains are larger than those of other animals has been identified by scientists from two stem-cell labs at UC San Francisco, in research published in the November 13, 2014 issue of Nature.
Key experiments by the UCSF researchers revealed that the protein, called PDGFD, is made in growing brains of humans, but not in mice, and appears necessary for normal proliferation of human brain stem cells growing in a lab dish.
The scientists made their discovery as part of research in which they identified genes that are activated to ...
LAST 30 PRESS RELEASES:
[Press-News.org] Mongoose sentinels respond flexibly to threats
