Navigation Links
Males' superior spatial ability likely is not an evolutionary adaptation
Date:2/19/2013

Males and females differ in a lot of traits (besides the obvious ones) and some evolutionary psychologists have proposed hypotheses to explain why. Some argue, for example, that males' slight, but significant, superiority in spatial navigation over females a phenomenon demonstrated repeatedly in many species, including humans is probably "adaptive," meaning that over the course of evolutionary history the trait gave males an advantage that led them to have more offspring than their peers.

A new analysis published in The Quarterly Review of Biology found no support for this hypothesis. The researchers, led by University of Illinois psychology professor Justin Rhodes, looked at 35 studies that included data about the territorial ranges and spatial abilities of 11 species of animals: cuttlefish, deer mice, horses, humans, laboratory mice, meadow voles, pine voles, prairie voles, rats, rhesus macaques and talastuco-tucos (a type of burrowing rodent). Rhodes and his colleagues found that in eight out of 11 species, males demonstrated moderately superior spatial skills to their female counterparts, regardless of the size of their territories or the extent to which males ranged farther than females of the same species. (Watch a video about the research.)

The findings lend support to an often-overlooked hypothesis, Rhodes said. The average superiority of males over females in spatial navigation may just be a "side effect" of testosterone, he said. (Previous studies have shown that women who take testosterone tend to see an improvement in their spatial navigation skills, he said.)

The analysis adds a new dimension to an ongoing debate about the evolutionary significance of some baffling human traits. Rhodes and his colleagues object to "creation stories" that seek to explain sexual phenomena like the female orgasm, rape or menopause by hypothesizing that they evolved because they provided an evolutionary advantage. Some evolutionary psychologists describe rape, for example, as an alternate mating strategy for males who otherwise are reproductively unsuccessful. Others say menopause evolved in women to enhance the survival of their genes by increasing the time spent nurturing their grandchildren. Some of these hypotheses seem intuitive, Rhodes said. "But these stories generally are not testable."

Researchers tend to overlook the fact that many physical and behavioral traits arise as a consequence of random events, or are simply side effects of other changes that offer real evolutionary advantages, he said.

"For example, women have nipples because it's an adaptation; it promotes the survival of their offspring," Rhodes said. "Men get it because it doesn't harm them. So if we see something that's advantageous for one sex, the other sex will get it because it's inheriting the same genes unless it's bad for that sex."

Similarly, scientists who claim that the different spatial skills in men and women are adaptive must explain why women failed to inherit the superior spatial skills of their navigationally enhanced fathers, Rhodes said.

"The only way you will get a sex difference (in an adaptive trait) is where a trait is good for one sex and bad for the other," he said. "But how is navigation bad for women? This is a flaw in the logic."

"When people hear arguments made or stories told, particularly about human behaviors being products of adaptation, I think they should ask the question: 'Where is the evidence?' " Rhodes said.

Rhodes is an affiliate of the Beckman Institute for Advanced Science and Technology at Illinois.


'/>"/>

Contact: Diana Yates
diya@illinois.edu
217-333-5802
University of Illinois at Urbana-Champaign
Source:Eurekalert  

Related medicine news :

1. Researchers Detect an Anti-Autism Advantage in Females
2. New OHSU research helps explain early-onset puberty in females
3. Males Struck by Cars Die More Often Than Females: Study
4. Survival of the females
5. High hormone levels put young black males at risk for cardiovascular disease
6. Asthma is all in the family among African males
7. Uncertain about health outcomes, male stroke survivors more likely to suffer depression than females
8. Rare brain blood vessel disease carries higher risks in females
9. Male Ontario students show declines in fighting; females show elevated bullying and mental distress
10. Females, Young Athletes Take Longer to Get Over Concussions
11. Red Cliff Band of Lake Superior Chippewa, Lake Superior Barrels Project Field Work
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Males' superior spatial ability likely is not an evolutionary adaptation
(Date:2/6/2016)... ... February 06, 2016 , ... Shark Finds and ... launch of a new DRTV campaign with Belly Bands. , Having a dog is ... sprays to puppy pads and find nothing works, get Belly Bands, the easiest ...
(Date:2/5/2016)... Bethpage, NY (PRWEB) , ... February 05, 2016 , ... ... florist-quality long-stem roses in a variety of colors, assortments and packaging. This staple for ... at any King Kullen location. , For Valentine’s Day, not only are long-stem ...
(Date:2/5/2016)... ... February 05, 2016 , ... Successful recruitment and retention efforts, ... scientific initiatives have all marked the last 12 months at Roswell Park Cancer ... the nation’s oldest cancer center, Candace S. Johnson, PhD, outlined the many accomplishments ...
(Date:2/5/2016)... ... 05, 2016 , ... Francisco Canales, MD and Heather Furnas, ... Valley office. The technique utilizes the body’s own healing abilities to quickly rejuvenate ... are part of only a select few cosmetic surgeons bringing this procedure to ...
(Date:2/5/2016)... (PRWEB) , ... February 05, 2016 , ... After years ... General Hospital Burn Unit, plastic and cosmetic surgeon Dr. Wayne Carman transitioned to chief ... Hospital. He successfully completed his first three-year term as chief and began a second ...
Breaking Medicine News(10 mins):
(Date:2/4/2016)... , Feb. 4, 2016 Worldwide ... achieve significant growth as next generation systems provide ... use radiology for cancer surgery. New systems pinpoint ... overdosing that has been such a problem previously, ... delivered. Radiosurgery robots take cancer surgery far beyond ...
(Date:2/4/2016)... 4, 2016 Summary Breast cancer, a ... the most common cancer in women worldwide, accounting for ... prevalent. The number of women diagnosed with breast cancer ... number of deaths has declined due to earlier diagnosis ... been revolutionized in the past four decades, especially with ...
(Date:2/4/2016)... DIEGO, Feb. 4, 2016  Aethlon Medical, Inc. ... affinity biofiltration devices to treat life-threatening diseases, today ... 2016 ended December 31, 2015. ... objectives set forth in our last quarterly call, ... reinforce our long-term objective to establish the Aethlon ...
Breaking Medicine Technology: