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:10/13/2017)... RIDGE, N.J. (PRWEB) , ... October 13, 2017 , ... ... annual Holly Day Market. Featuring a collection of specialty vendors and unique items from ... of personalized and quality-focused health and wellness services offered by the VNA. The ...
(Date:10/13/2017)... , ... October 13, 2017 , ... Yisrayl Hawkins, Pastor ... that explains one of the most popular and least understood books in the Holy ... and puzzling descriptions that have baffled scholars for centuries. Many have tossed it off ...
(Date:10/13/2017)... ... October 13, 2017 , ... “The Journey: From the ... danger possible to save lost souls in the Philippines. “The Journey: From the Mountains ... a dedicated teacher of the Bible. She has taught all ages and currently teaches ...
(Date:10/12/2017)... , ... October 12, 2017 , ... ... now treating sleep apnea using cutting-edge Oventus O2Vent technology. As many ... sleep disorder characterized by frequent cessation in breathing. Oral appliances can offer significant ...
(Date:10/12/2017)... PALM CITY, Fla. (PRWEB) , ... October 12, 2017 , ... ... of cold therapy products, announced today the introduction of an innovative new design of ... the multipurpose pad so you get maximum comfort while controlling your pain while using ...
Breaking Medicine News(10 mins):
(Date:10/11/2017)... , Oct. 11, 2017  BioPharmX Corporation (NYSE MKT: ... that developed an innovative way to use nonlinear optical ... delivery of new drugs. ... Dermatology Conference will show how researchers from BioPharmX and ... Medical School used a suite of imaging techniques in ...
(Date:10/10/2017)... Calif. , Oct. 10, 2017  NDS received FDA 510(k) ... — a medical-grade battery-powered display stand specifically designed for endoscopy environments. ... transform technology into a clinical solution to support the improvement of ... Innovative Design ... Mobile Wireless Solution ...
(Date:10/4/2017)... SEOUL, South Korea , Oct. 4, 2017 /PRNewswire/ ... launched its next-generation CPR training aide "cprCUBE" on Kickstarter. ... of chest compression during cardiac arrests with better efficiency ... patient-mannequins. It also offers real-time feedback on efficacy of ... The crowdfunding campaign has a goal to raise ...
Breaking Medicine Technology: