PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Why are there no hyenas in Europe?

Why are there no hyenas in Europe?
2010-09-24
(Press-News.org) A team from the National Museum of Natural Sciences (CSIC) has analysed the impact of climate change on spotted hyena survival in Europe over 10,000 years ago. These changes played an important role, but the scientists say studies are still needed to look at the influence of human expansion and changes in herbivorous fauna on the definitive extinction of this species across the continent.

"Climate change in the past was not directly responsible for the extinction of the spotted hyena in southern Europe, but it was a factor in its disappearance", Sara Varela, lead author of the study and a researcher at the National Museum of Natural Sciences (CSIC), tells SINC.

According to the study, which has been published in the Journal Quaternary Science Reviews, the hyena populations of Africa and Eurasia became separated during the glacial maximum. And "the climatic conditions in southern Europe 21,000 years ago were extreme for this species", says Varela.

At that time, the European climate was undergoing "drastic" changes, as were herbivorous fauna populations and human expansion. According to the expert, "the survival of the hyenas could have been affected by the combination of these three factors acting in synergy, but not by the action of the climate alone".

Her team studied climate change in the past and identified the most favourable areas for the hyena in Europe, using modelling to look at the various climate scenarios of the Pleistocene. A second model estimated the severity of climate conditions for the survival of these animals. "The climatic conditions in the south of Europe were at all times within the tolerance range of this species", Varela points out.

Everything happened in the late Pleistocene

The spotted hyena (Crocuta crocuta) became extinct at the end of the late Pleistocene (around 10,000 years ago), coinciding with the last glacial maximum and the expansion of Homo sapiens. Large species disappeared forever, but the spotted hyena held out for a while and modified its geographical range in order to survive.

The distribution of the spotted hyena, a carnivore that is common in sub-Saharan Africa, has changed "substantially" from the Pleistocene until the present. Today it is only found in Africa, but during the Pleistocene (almost one million years ago), the spotted hyena also inhabited Eurasia.



INFORMATION:

References: Varela, Sara; Lobo, Jorge M.; Rodríguez, Jesús; Batra, Persaram. "Were the Late Pleistocene climatic changes responsible for the disappearance of the European spotted hyena populations? Hindcasting a species geographic distribution across time" Quaternary Science Reviews 29(17-18): 2027-2035, agosto de 2010. doi:10.1016/j.quascirev.2010.04.017


[Attachments] See images for this press release:
Why are there no hyenas in Europe?

ELSE PRESS RELEASES FROM THIS DATE:

Dust models paint alien's view of the solar system

Dust models paint aliens view of the solar system
2010-09-24
GREENBELT, Md. -- New supercomputer simulations tracking the interactions of thousands of dust grains show what the solar system might look like to alien astronomers searching for planets. The models also provide a glimpse of how this view might have changed as our planetary system matured. "The planets may be too dim to detect directly, but aliens studying the solar system could easily determine the presence of Neptune -- its gravity carves a little gap in the dust," said Marc Kuchner, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Md. who led ...

New species of multi-horned dinosaurs unearthed in Utah

2010-09-24
"A giant rhino with a ridiculously supersized head." "Fifteen long, pointed sideways oriented eye horns: one over the nose, one atop each eye, one at the tip of each cheek bone, and ten across the rear margin of the bony frill." "A horned face: large horn over the nose and short, blunt eye horns that project strongly to the side." Such phrases have been used to describe two newly discovered species of dinosaurs with looks only a mother could love. Still, they are drawing the attention and inspiring the imagination of scientists and lay people alike. Announced today ...

More predators doesn't equal more danger for urban bird nest

2010-09-24
COLUMBUS, Ohio – While birds living in urban areas face more predators than do those in rural areas, that doesn't mean urban birds face more danger from nest robbers. A six-year study conducted in 19 central Ohio forests from 2004 to 2009 found that, as expected, rural areas that had higher numbers of nest predators such as raccoons, domestic cats, and crows, also showed lower rates of nest survival. But there was no relation between the number of predators and nest survival in more urbanized areas. Researchers believe that's because nest predators in urban areas ...

Increased attention to women's health research has yielded gains on some important conditions, but progress lags on others

2010-09-24
WASHINGTON -- A concerted effort to boost research on women's health over the last two decades has lessened the burden of disease and reduced deaths among women due to cardiovascular disease, breast cancer, and cervical cancer, says a new report from the Institute of Medicine. The effort has yielded less but still significant progress in reducing the effects of depression, HIV/AIDS, and osteoporosis on women, added the committee that wrote the report. However, several health issues important to women have seen little progress, including unintended pregnancy, autoimmune ...

Everglades restoration program making tangible progress after 10 years; challenges ahead to meet both water quality and quantity goals

2010-09-24
WASHINGTON -- A decade-long, multibillion dollar effort to restore the Florida Everglades has made tangible albeit slow progress, but additional projects need completion before substantial benefits are seen, says a new congressionally mandated report from the National Research Council. Challenges in achieving targets for both water quality and water flow have become more apparent, requiring further scientific analysis to determine the repercussions of trading off one for the other. Although important scientific advances have been made, continued decline of some aspects ...

Vitamin C rapidly improves emotional state of acutely hospitalized patients, say LDI researchers

2010-09-24
Treatment with vitamin C rapidly improves the emotional state of acutely hospitalized patients, according to a study carried out by researchers at Montreal's Jewish General Hospital (JGH) and the affiliated Lady Davis Institute for Medical Research (LDI). In a double-blind clinical trial, patients admitted to the JGH were randomly assigned to receive either vitamin C or vitamin D supplements for seven to ten days. Patients administered vitamin C had a rapid and statistically and clinically significant improvement in mood state, but no significant change in mood occurred ...

Scientists recreate extreme conditions deep in Earth's interior

Scientists recreate extreme conditions deep in Earths interior
2010-09-24
New Haven, Conn.—Scientists have wondered for some time why certain seismic waves travel more quickly through the core-mantle boundary, a thin layer of the Earth's interior that lies between about 1675 and 1800 miles below the surface. Now a new study by Yale University and the University of California, Berkeley sheds light on the mystery by showing how this region behaves under the extreme conditions found so deep in the Earth. The findings, which appear in the Sept. 24 issue of the journal Science, have important implications for understanding how the Earth's internal ...

Current decisions shape your future preferences

2010-09-24
Psychologists have known for a long time that after you make a choice, you adjust your opinion to think better of the thing you chose. Now a new study has found that this is true even if you don't know the options that you're choosing between. People change their minds about a choice after they make it. If you ask someone how he feels about Athens and Paris, he might rate them the same. But after you make him choose one as a vacation destination, he'll rate that city higher. This is thought to be a way to reduce the psychological tension that is created by rejecting ...

Arctic soil study turns up surprising results

2010-09-24
Across the globe, the diversity of plant and animal species generally increases from the North and South Poles towards the Equator but surprisingly that rule isn't true for soil bacteria, according to a new study by Queen's University biology professor Paul Grogan. "It appears that the rules determining the patterns for plant and animal diversity are different than the rules for bacteria," says Professor Grogan. The finding is important because one of the goals in ecology is to explain patterns in the distribution of species and understand the biological and environmental ...

New technique uncovers hidden insecticide resistance

New technique uncovers hidden insecticide resistance
2010-09-24
A new technique pioneered at Liverpool School of Tropical Medicine (LSTM) is improving the detection and monitoring of insecticide resistance in field populations of an important malaria-carrying mosquito. Researchers at LSTM, led by Dr Charles Wondji have developed a new technique which encourages the female Anopheles funestus mosquitoes to lay eggs which are then reared into adult mosquitoes to provide sufficient numbers to determine levels of insecticide resistance and to characterise the underlying mechanisms. Explaining the significance, John Morgan, who designed ...

LAST 30 PRESS RELEASES:

New jab protects babies from serious lung infection, study shows

July Tip Sheet from Sylvester Comprehensive Cancer Center

Current application status and innovative development of surgical robot

Counterfeited in China: New book assesses state of industry and its future

Machine learning reveals historical seismic events in the Yellowstone caldera

First analyses of Myanmar earthquake conclude fault ruptured at supershear velocity

Curved fault slip captured on CCTV during Myanmar earthquake

Collaboration rewarded for work to further deployment of batteries in emerging economies

Heart-healthy habits also prevent cancer, Alzheimer’s, COPD, other diseases, Emory study finds

Scientists will use a $1M grant to build a support system addressing sea level rise and flooding in South Florida

New research examines how pH impacts the immune system

Inhaled agricultural dust disrupts gut health

New study reveals hidden regulatory roles of “junk” DNA

Taking the sting out of ulcerative colitis

Deep life’s survival secret: Crustal faulting generates key energy sources, study shows

Idaho National Laboratory to lead advancements in US semiconductor manufacturing

AI-assisted sorting, other new technologies could improve plastic recycling

More than just larks and owls!

Call for nominations: 2026 Dan David Prize

New tool gives anyone the ability to train a robot

Coexistence of APC and KRAS mutations in familial adenomatous polyposis and endometrial cancer: A mini-review with case-based perspective

First global-to-local study reveals stark health inequalities from COVID-19 in 2020–2021

rcssci: Simplifying complex data relationships with enhanced visual clarity

Why some ecosystems collapse suddenly—and others don’t

One-third of U.S. public schools screen students for mental health issues

GLP-1 RA use and survival among older adults with cancer and type 2 diabetes

Trends in physician exit from fee-for-service Medicare

Systematic investigation of tumor microenvironment and antitumor immunity with IOBR

Common feature between forest fires and neural networks reveals the universal framework underneath

New R package revolutionizes gene set enrichment analysis visualization for biomedical research

[Press-News.org] Why are there no hyenas in Europe?