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:6/26/2016)... ... 2016 , ... Pixel Film Studios Released ProSlice Levels, a Media Slicing Effect ... videos a whole new perspective by using the title layers in ProSlice Levels ... , ProSlice Levels contains over 30 Different presets to choose from. FCPX ...
(Date:6/26/2016)... ... June 26, 2016 , ... Many ... been diagnosed with endometriosis. These women need a treatment plan to not only ... approach that can help for preservation of fertility and ultimately achieving a pregnancy. ...
(Date:6/25/2016)... ... 2016 , ... The temporary closing of Bruton Memorial Library on June 21 due to a ... new, often overlooked aspect of head lice: the parasite’s ability to live away from a ... occurrence, but a necessary one in the event that lice have simply gotten out of ...
(Date:6/25/2016)... ... June 25, 2016 , ... As a lifelong Southern ... Laude and his M.D from the David Geffen School of Medicine at UCLA. He ... Los Angeles to complete his fellowship in hematology/oncology at the UCLA-Olive View-Cedars Sinai program ...
(Date:6/25/2016)... ... June 25, 2016 , ... Conventional wisdom preaches the benefits of moderation, whether ... latter, setting the bar too high can result in disappointment, perhaps even self-loathing. However, ... their goal. , Research from PsychTests.com reveals that behind the tendency ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... 2016 The Academy of Managed Care Pharmacy ... that would allow biopharmaceutical companies to more easily share ... formulary and coverage decisions, a move that addresses the ... The recommendations address restrictions in the sharing ... drug label, a prohibition that hinders decision makers from ...
(Date:6/24/2016)... , June 24, 2016  American Respiratory Labs (ARL), a ... now able to perform sophisticated lung assessments in patients, homes, thanks ... Inc. Patients are no longer limited to having ... PRO ® , ARL patients like Jeanne R. of ... the comfort of her own home. ...
(Date:6/24/2016)... , June 24, 2016 ... Market by Type (Standard Pen Needles, Safety Pen Needles), ... (Insulin, GLP-1, Growth Hormone), Mode of Purchase (Retail, Non-Retail) ... MarketsandMarkets, This report studies the market for the forecast ... to reach USD 2.81 Billion by 2021 from USD ...
Breaking Medicine Technology: