Navigation Links
Females decide whether ambitious males float or flounder
Date:1/30/2008

Hamilton, ON. January 30, 2007 Aggression, testosterone and nepotism dont necessarily help one climb the social ladder, but the support of a good female can, according to new research on the social habits of an unusual African species of fish.

The study, published today in the journal Proceedings of the Royal Society, highlights the complex relationship between social status, reproductive physiology and group dynamics.

We found that changes in social status were regulated by the most dominant female in a social group, says John Fitzpatrick, lead researcher and a graduate student in the department of Biology at McMaster University. In fact, dominant females seemed to act as gatekeepers, allowing only males larger than themselves to move up in status and become dominant.

Males rising to a dominant social position, says Fitzpatrick, instantly altered their behaviour, becoming more aggressive. In addition, they dramatically ramped up their reproductive physiology, almost doubling the size of their testes in one week.

Working underwater off the Zambian shores of Lake Tanganyika in Africa, the researchers examined how males respond to changes in social position in the cichlid fish, Neolamprologus pulcher. This species lives in permanent social groups made up of a dominant male and female breeding pair and subordinate males and females that help this pair look after young and defend territory.

By removing the male breeders, researchers created vacancies and provided an opportunity for subordinate males to rise through the ranks.

Hormones and genetic relationships didnt necessarily determine who gets to be top dog, says Sigal Balshine, the senior author on the study and an associate professor in the department of Psychology, Neuroscience & Behaviour. Most folks would have thought that how aggressive you are, how big and powerful you are or how much testosterone you have might be important in understanding status change and dominance rankings. Our study combined several approaches to show that simply isnt the case instead, the female and the social landscape are key.


'/>"/>

Contact: Michelle Donovan
donovam@mcmaster.ca
905-525-9140
McMaster University
Source:Eurekalert

Related medicine news :

1. Researchers discover correlation between GERD and obesity in females
2. Females avoid incest by causing male relatives to leave home
3. The Polls are Open! America Votes to Decide Which Hospital is the Most Deserving of Siemens Newest MRI Technology
4. American Cancer Society Seeks Volunteers to Help Decide Who Gets Research Grants
5. Study reveals how stem cells decide to become either skeletal or smooth muscle
6. MedQuist Evaluating Whether a Sale of the Company is in the Best Interests of the Company and its Shareholders
7. Study fuels debate over whether exercise and body size influence ovarian cancer risk
8. Doctors and Medical Ethicist Discuss Whether Doctors Should Participate in Capital Punishment
9. Doctors and medical ethicist discuss whether doctors should participate in capital punishment
10. New upper limit defined for normal ALT in adolescent males
11. Floating effective for stress and pain
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:10/12/2017)... ... October 12, 2017 , ... The ... demand of today’s consumer and regulatory authorities worldwide. From Children’s to Adults 50+, ... to meet the highest standard. , These products are also: Gluten Free, ...
(Date:10/12/2017)... ... ... Asante, a nationally recognized health system in southern Oregon, ... health joint venture through an agreement, effective October 1, 2017, to create AccentCare ... company with Asante, delivering clinically integrated care, for the past eight years. This ...
(Date:10/12/2017)... ... 2017 , ... HMP , a leader in healthcare events and education, today ... Digital Award for ‘Best B-to-B Healthcare Website.’ Winners were announced during the Eddie & ... award competition recognizes editorial and design excellence across a range of sectors. This year’s ...
(Date:10/12/2017)... ... October 12, 2017 , ... Women-owned and Grand Rapids-based workplace ... Brightest in Wellness® by Best and Brightest. OnSite Wellness will be honored at ... from 7:30 a.m. to 2 p.m. at the Henry Autograph Collection Hotel, located ...
(Date:10/12/2017)... ... 12, 2017 , ... Vohra Chief Medical Officer Dr. Shark ... skilled nursing facility medical directors and other clinicians at various events in October. ... "At many of these conferences we get to educate other physicians, facility nurses, ...
Breaking Medicine News(10 mins):
(Date:10/7/2017)... 6, 2017   Provista, a proven leader ... billion in purchasing power, today announced a new resource ... The Newsroom is the online home for case ... expert bios, news releases, slideshows and events. ... wealth of resources at their fingertips, viewers can also ...
(Date:10/2/2017)... , Oct. 2, 2017 Diplomat Pharmacy, ... 8th Day Software and Consulting, LLC , and named ... 8th Day Software, based in Tennessee , ... 8th Day expands EnvoyHealth,s service offerings for health care ... "In an interoperable ...
(Date:9/28/2017)... 28, 2017 Hill-Rom Holdings, Inc. (NYSE: HRC), ... call and webcast on Friday, November 3, 2017, beginning ... ending at approximately 8:30 a.m. (CDT) / 9:30 a.m. ... 2017 financial performance and guidance for 2018, Hill-Rom executives ... enhance operational performance, and long-range financial outlook through 2020. ...
Breaking Medicine Technology: