(Press-News.org) The dormouse in Alice in Wonderland was well advised to stay asleep – especially as doing so did not prevent it from taking a full part in the tea-time conversation. Dormice in Europe spend about eight months of the year asleep and are extremely safe during this extended period, with almost all of them surviving the winter. This result comes from a study of dormouse survival rates in Austria, the Czech Republic, England, Germany and Italy.
Karin Lebl was a PhD student in Ruf's group. Together with collaboration partners in these countries, she examined how the survival of dormice living in the wild varies according to a number of factors, including the time of the year, various climatic factors and the animals' reproductive behaviour. In contrast to some species of marmot, for which hibernation is known to be associated with high mortality rates, the dormouse seems well able to accumulate enough fat reserves to survive even the harshest winter. Nevertheless, the work of Ruf's group showed that dormice in all five study countries are particularly vulnerable in early spring, immediately after they awake from hibernation. The animals clearly lose weight as a result of spending eight months without food, so afterwards they spend a large amount of time foraging, which presumably makes them more susceptible to predators: owls, weasels, pine martens and both wild and domestic cats.
The risk of having young
Unusually for small mammals, dormice do not breed every year. Instead, they "save" their reproductive efforts for years when there are good supplies of acorns or beech nuts. Such events occur irregularly and at different rates: in Germany, for example, seeding is considerable more frequent than in the study area in the northern Italian Alps. Lebl and Ruf found that mortality rates were significantly higher in years when the animals had young than in years when they did not. This may relate to the increased time the parents spend looking for food for their young or it may stem from the direct energy costs of reproduction. The upshot, though, is that dormice in "good" habitats in Germany, where oaks and beech trees frequently produce seeds, live on average for less than four years while dormice in the "poorer" habitats in northern Italy live on average for more than twice as long. Perhaps because they expect to die younger, German dormice tend to have larger litters than their longer-lived Italian cousins. Even so, dormice in Germany simply do not have time to produce the same number of young in their lifetimes as dormice in Italy.
So why do dormice in the Italian Alps live for so long? As Ruf says, "we can't really explain it. Despite what we may think, differences in the climate cannot account for our results – and we have no evidence to suggest that climate change is having any effect on the animals' survival. Our working hypothesis is that the major factor influencing the dormouse population is the type and number of predators. Maybe there are fewer predators in Italy or perhaps the Italian dormice have particularly successful methods for avoiding being eaten."
###
The paper Survival rates in a small hibernator, the edible dormouse: a comparison across Europe by Karin Lebl, Claudia Bieber, Peter Adamík, Joanna Fietz, Pat Morris, Andrea Pilastro and Thomas Ruf has recently been published online by the journal Ecography and is available at http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0587.2010.06691.x/abstract
About the University of Veterinary Medicine, Vienna
The University of Veterinary Medicine, Vienna is the only academic and research institution in Austria that focuses on the veterinary sciences. About 1000 employees and 2300 students work on the campus in the north of Vienna, which also houses the animal hospital and various spin-off-companies. The Research Institute of Wildlife Ecology is part of the new Department for Integrative Biology and Evolution; its research focuses on the needs and behaviour of wild animals in their natural contexts.
http://www.vetmeduni.ac.at, http://www.fiwi.at
Sleeping through danger: the dormouse approach to survival
2011-04-02
ELSE PRESS RELEASES FROM THIS DATE:
A new experimental diagnostic test able to quickly distinguish infection from tuberculosis disease
2011-04-02
A potential new experimental diagnostic test able to quickly distinguish individuals with active tuberculosis (TB) from those with latent TB infection has been developed. If the preliminary results of the study will be confirmed in a larger population sample, the new diagnostic system could allow more effective strategies to control the spread of the re-emerging pathology.
The work was performed by a group of scientists from the Catholic University of Rome, the National Institute of Infectious Diseases "L. Spallanzani" of Rome and the University of Sassari, in a study ...
Anti-Hispanic Discrimination Still Felt Around the Country
2011-04-02
A recent survey performed by the Pew Hispanic Center (PHC) found that over 60 percent of Hispanics polled still feel that they are the victims of national origin bias. The PHC -- a nonpartisan, nonprofit research group -- is focused on tracing trends in attitude and lifestyle that affect Latinos and others of Hispanic origin living in America.
The striking percentage of disenfranchised Hispanics is a sharp uptick in the numbers of those who felt discriminated against in recent years, and most blame the rise in bias as being the direct result of America's highly publicized ...
Advance in microchannel manufacturing opens new industry applications
2011-04-02
CORVALLIS, Ore. – Engineers at Oregon State University have invented a new way to use surface-mount adhesives in the production of low-temperature, microchannel heat exchangers - an advance that will make this promising technology much less expensive for many commercial applications.
This type of technology will be needed, researchers say, in next-generation computers, lasers, consumer electronics, automobile cooling systems, fuel processors, miniature heat pumps and more.
New industries and jobs are possible. A patent has been applied for, the findings reported in ...
'SKIP'-ing splicing forces tumor cells to undergo programmed cell death
2011-04-02
LA JOLLA, CA—When cells find themselves in a tight spot, the cell cycle regulator p21 halts the cell cycle, buying cells time to repair the damage, or if all else fails, to initiate programmed cell death. In contrast to other stress-induced genes, which dispense with the regular transcriptional entourage, p21Cip1 still requires SKIP, a transcription elongation factor that also helps with the editing of transcripts, to be expressed, found researchers at the Salk Institute for Biological Studies.
In the absence of SKIP, the expression of p21Cip1 is rapidly down-regulated, ...
U-M experts: Parents trust doctors most when it comes to information about vaccine safety
2011-04-02
ANN ARBOR, Mich. – Most parents get their information about vaccines from their children's doctors, but some also consider public health officials, other parents, friends and family members and even celebrities as sources of vaccine information.
These are the results of a national survey conducted by University of Michigan researchers to determine how much parents trust different sources of information in regards to vaccines, as well as to determine what disseminating methods would be most effective for those distributing evidence-based information about vaccines.
The ...
Florida Judge Rules New Health Care Law Unconstitutional: What is Next?
2011-04-02
In late January, a district court judge in Florida issued a lengthy opinion holding that the new federal health care reform act shepherded into law by President Obama is unconstitutional. Although news of the ruling has traveled fast, many are wondering just what the decision means for the future of the health care law.
The Case
In a joint lawsuit involving 26 states, Federal District Court Judge Roger Vinson found that the health care law popularly known as Obamacare overstepped the authority granted to Congress by the U.S. Constitution. Specifically, Judge Vinson ...
Surprising finding from smoke inhalation study
2011-04-02
MAYWOOD, Ill. -- An award-winning Loyola University Health System study includes some unexpected findings about the immune systems of smoke-inhalation patients.
Contrary to expectations, patients who died from their injuries had lower inflammatory responses in their lungs than patients who survived.
"Perhaps a better understanding of this early pulmonary immune dysfunction will allow for therapies that further improve outcomes in burn care," researchers reported.
Results were released at the 43rd annual meeting of the American Burn Association. The project won the 2011 ...
Insulin could be Alzheimer's therapy
2011-04-02
BUFFALO, N.Y. -- A low dose of insulin has been found to suppress the expression in the blood of four precursor proteins involved in the pathogenesis of Alzheimer's disease, according to new clinical research by University at Buffalo endocrinologists. The research, published in March online in the Journal of Clinical Endocrinology and Metabolism, suggests that insulin could have a powerful, new role to play in fighting Alzheimer's disease.
"Our results show clearly that insulin has the potential to be developed as a therapeutic agent for Alzheimer's, for which no satisfactory ...
Jumeirah Opens its First Hotel in Pudong, China
2011-04-02
Jumeirah Group, the Dubai-based luxury hotel company and a member of Dubai Holding, has announced the soft opening of its first five-star luxury hotel in China at the Himalayas Centre in Pudong, Shanghai.
Jumeirah Himalayas Hotel Shanghai features 401 contemporary Chinese-style guestrooms, including 62 suites and residences, four restaurants and lounges, a 24-hour fitness centre and indoor swimming pool. The hotel also offers extensive meeting, conference and event facilities, including two grand ballrooms and a 5000m2 rooftop Infinity Garden, perfect for weddings and ...
Prudential Reveals Number of Poverty Line Pensioners on the Rise
2011-04-02
Prudential has revealed that more than a third (35 per cent) of people planning to retire in the UK this year will do so with incomes below the poverty line.
To meet its minimum income standard the Joseph Rowntree Foundation, the charity that funds a large, UK-wide research and development programme, estimates that a single person in the UK needs at least GBP14,400 a year, yet 35 per cent of those retiring in 2011 will have a retirement income below this level, up from 32 per cent in 2010.
Prudential's Class of 2011 study surveyed people intending to retire this year ...