When it comes to selecting a mate, the eyes have it: Queen's University study
2010-12-14
(Press-News.org) For the first time ever, scientists have found a difference in the way males and females of the same species of vertebrate see things – and that sexes likely use that difference to select their mates.
Queen's PhD candidate Shai Sabbah, a Vanier Scholar, led a team of researchers who found that male and female cichlid fishes not only see things differently, but detect light in different ways as well.
"It is difficult to say what colour attracts the female the most, but we know that if we manipulate the colour of the fish by changing the light in the environment, the female fish will fail to choose a male of her own species," says Mr. Sabbah.
In nature, increased water turbidity due to deforestation and human development alters the visual environment of fish and consequently, impairs visually-mediated tasks such as mate choice. That can endanger the survival of the species and eventually lead to a reduction in diversity.
"These fish depend on colour vision for their own survival, so discovering differences in the highly dimensional visual systems of males and females is a significant finding," says Mr. Sabbah.
The research team also discovered that the fish have five different photoreceptor cones in their eyes, the most ever found in a vertebrate. Cones are what enable the eye to detect colours. Humans, by comparison, have just three photoreceptor cones. This gives cichlids the potential for very good discrimination between colours, which they need in order to choose a correct mate.
Cichlids are small, colourful fish found in many lakes around the world and in aquariums in North America. Female cichlids are dull in colour, while males are vibrant and often show colourful body markings.
Colour vision plays a key role in visual behavior. Mr. Sabbah and other members in Craig Hawryshyn's laboratory are currently looking at how differences in visual abilities affect the behavior of male and female cichlids.
The findings were recently published in BMC Biology, an online open access scientific journal that publishes original, peer-reviewed research in all fields of biology.
INFORMATION: END
ELSE PRESS RELEASES FROM THIS DATE:
2010-12-14
Increased life expectancy in the United States has not been accompanied by more years of perfect health, reveals new research published in the December issue of the Journal of Gerontology.
Indeed, a 20-year-old today can expect to live one less healthy year over his or her lifespan than a 20-year-old a decade ago, even though life expectancy has grown.
From 1970 to 2005, the probability of a 65-year-old surviving to age 85 doubled, from about a 20 percent chance to a 40 percent chance. Many researchers presumed that the same forces allowing people to live longer, including ...
2010-12-14
UCSF researchers have identified an existing medication that restores key elements of the immune system that, when out of balance, lead to a steady decline in immunity and health as people age.
The team found that extremely low doses of the drug lenalidomide can stimulate the body's immune-cell protein factories, which decrease production during aging, and rebalance the levels of several key cytokines – immune proteins that either attack viruses and bacteria or cause inflammation that leads to an overall decline in health.
The initial study, which was designed to define ...
2010-12-14
Early years initiatives for pre-school children are not delivering improvements in language and numeracy development, according to leading education experts.
Experts, conducting one of the largest surveys to date of the development of 117,000 children starting primary school in England over eight years, found that despite a raft of early years' initiatives, such as 'Sure Start', basic levels of development in early reading, vocabulary and maths have remained largely unchanged.
Researchers from the Centre for Evaluation and Monitoring (CEM) at Durham University who ...
2010-12-14
Ann Arbor, Mich.— Expression of a toxic RNA that leads to Fragile X Tremor Ataxia Syndrome is modifiable by genetic or pharmacologic means, according to new research from U-M Medical School scientists.
In the study published online today in the journal Public Library Of Science Genetics, U-M's Peter K. Todd, M.D., Ph.D., led a team of researchers who examined the expression of a toxic messenger RNA (mRNA) seen in the brains of those afflicted with the syndrome.
Fragile X Tremor Ataxia Syndrome (FXTAS) is usually found in older adults, who often have grandchildren afflicted ...
2010-12-14
Mexican-Americans who are most integrated into the culture -- including those born in the United States, and not recent immigrants -- appear less healthy and more likely to require resources to manage their health conditions than more recent, less-integrated migrants, according to a new study from Rice University, Duke University and the University of Colorado Denver.
In particular, the research reveals that this pattern of declining health among immigrants who are in the U.S. the longest holds more strongly for men than women. Conversely, the research indicates that, ...
2010-12-14
WEST LAFAYETTE, Ind. - Face-to-face workplace interactions may be the best way to educate and encourage people to consider becoming organ donors, according to new research from Purdue University.
"Workplaces are a key location for people to learn about health and wellness issues, but how information is distributed in this setting can make a difference for sensitive health topics such as organ donation," said Susan E. Morgan, a professor of communication. "There is an incredible amount of misinformation and medical mistrust surrounding the organ donation process, which ...
2010-12-14
A one-year follow-up study on seniors who participated in a strength training exercise program shows sustained cognitive benefits as well as savings for the healthcare system. The research, conducted at the Centre for Hip Health and Mobility at Vancouver Coastal Health and the University of British Columbia, is published today in the Archives of Internal Medicine.
The study is the first to examine whether both cognitive and economic benefits are sustained after formal cessation of a tailored exercise program. It builds on the Brain Power Study, published in the January ...
2010-12-14
Results from a government-sponsored clinical trial of inactivated 2009 H1N1 influenza vaccine in people with asthma indicate that a single dose of vaccine was safe and induced a strong immune response predictive of protection. The findings also suggest that individuals over the age of 60 who have severe asthma may require a larger dose of vaccine.
The study was cosponsored by the National Institute of Allergy and Infectious Diseases (NIAID) and the National Heart, Lung, and Blood Institute (NHLBI), two components of the National Institutes of Health, and appears online ...
2010-12-14
WEST LAFAYETTE, Ind. - Changes in diet have been linked to a reduction of abnormal behaviors in mentally ill people or animals, but a Purdue University study shows that diet might also trigger the onset of mental illness in the first place.
Joseph Garner, an associate professor of animal sciences, fed mice a diet high in sugar and tryptophan that was expected to reduce abnormal hair-pulling. Instead, mice that were already ill worsened their hair-pulling behaviors or started a new self-injurious scratching behavior, and the seemingly healthy mice developed the same abnormal ...
2010-12-14
CHAMPAIGN, Ill. – The Obama administration's decision to maintain a ban on oil drilling in the eastern Gulf of Mexico and off the Atlantic and Pacific coasts is a mistake, according to a University of Illinois expert who wrote a six-volume book series on marine pollution.
"It's a ridiculous decision on the part of the Interior Department," said John W. Kindt, a professor of business and legal policy at Illinois. "The previous 180-day moratorium really hurt a lot of businesses. Well, a seven-year ban is going to sting even more."
Kindt says giving the oil companies a ...
LAST 30 PRESS RELEASES:
[Press-News.org] When it comes to selecting a mate, the eyes have it: Queen's University study
