Navigation Links
Status symbols of house sparrows
Date:6/4/2010

The size of the black breast bib the badge - and bill colour of male House Sparrows change over the course of the year. Such ornaments usually signal quality and dominance of a male to his conspecifics and are correlated with his testosterone levels. These levels are generally higher before and during breeding season than for example during moult in autumn. A team of scientists at the Max Planck Institute for Ornithology in Seewiesen, Germany, recently demonstrated in a detailed study that only bill colour was correlated with the amount of testosterone in the blood. In contrast, the size of the badge was independent of hormone levels (Published online in Behavioural Ecology and Sociobiology, May 29th 2010).

Sparrows live in social groups. All year round males engage in aggressive interactions to establish dominance ranks. External traits such as badge and bill colour so called ornaments serve as signals for conspecifics. For example, the bigger the comb of a rooster the more dominant he is. The elaboration of many such sexually selected ornaments from all kinds of animals depends on the hormone testosterone, which also causes dominant and aggressive behaviour. Nevertheless, these ornaments have inescapable costs because high blood testosterone levels suppress the immune system and stress resistance, and could thus eventually be costly for the animal. Therefore, ornaments are also called honest signals; only high quality animals can afford these costs.

Scientists at the Max Planck Institute for Ornithology in Seewiesen, Germany, were not only interested in the relationship between the elaboration of ornaments of male House Sparrows and blood testosterone levels but also if and how these relationships change over the course of a year. "The comparison of different seasons is a very important approach: the size of the badge is determined during moult in autumn, but maybe only important during the breeding season when the white feather ed
'/>"/>

Contact: Silke Laucht
laucht@orn.mpg.de
49-081-579-32320
Max-Planck-Gesellschaft
Source:Eurekalert

Page: 1 2

Related biology news :

1. Sequella receives US and EU orphan drug status for SQ109 for the treatment of TB
2. Study identifies trends of vitamin B6 status in US population sample
3. Promptu and OAG Team to Deliver Flight Schedule and Status Information on Mobile Devices
4. U of Minnesota researcher finds link between aggression, status and sex
5. Chemistry professor 1 of only 3 at UH to achieve prestigious AAAS status
6. People of higher socioeconomic status choose better diets -- but pay more per calorie
7. Hypertension among lower-status employees lingers well into retirement
8. Alert status area in brain discoved by Hebrew University scientists
9. Ambry Genetics Announces Certified Service Provider Status for Agilent Microarrays
10. Low socioeconomic status affects cortisol levels in children over time
11. Gas improves blood flow and organ status during minimally invasive surgery
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:7/9/2014)... bladders of healthy women differ from bacteria in ... to researchers from Loyola University Chicago Stritch School ... 9, 2014, in the American Society for Microbiology,s ... communities may play a role in female urinary ... common, yet poorly understood, condition with symptoms similar ...
(Date:7/9/2014)... Centre (CNIO) have discovered that NANOG, an essential gene ... stratified epitheliathose that form part of the epidermis of ... adult organisms. According to the conclusions of the study, ... factor could also play a role in the formation ... and skin. , The pluripotency factor NANOG is active ...
(Date:7/9/2014)... studying critically ill children with traumatic injuries have ... are likely to develop a hospital-acquired infection. The ... and published online in June in the journal ... efforts that could lead to the clinical implementation ... prevent or reverse immune system damage following critical ...
Breaking Biology News(10 mins):CNIO scientists discover that pluripotency factor NANOG is also active in adult organisms 2Immune function predicts infection risk among child trauma patients 2Immune function predicts infection risk among child trauma patients 3
... Dana-Farber Cancer Institute (Dana-Farber), Burnham Institute for Medical ... and Prevention (CDC) have reported the identification of ... range of influenza A viruses, including avian influenza ... some seasonal influenza viruses. These antibodies have the ...
... International, Inc. (OTC Bulletin Board: BKYI), a leader in ... today that it will participate in Imperial Capital,s Homeland ... of March. Additional details regarding BIO-key,s participation at ... , Imperial Capital,s ...
... Permanently Disposes Magnetically Recorded Data to Help QSGI,s ... Calif., Feb. 18 Fujitsu Computer Products of ... products including hard disk drives, peripherals and biometric ... using the Fujitsu Mag EraSURE degaussing ...
Cached Biology News:Scientists identify human monoclonal antibodies effective against bird and seasonal flu viruses 2Scientists identify human monoclonal antibodies effective against bird and seasonal flu viruses 3BIO-key(R) Announces Conference Schedule 2QSGI Integrates Fujitsu Mag EraSURE Data Degausser into its Suite of Information Technology Security Services 2QSGI Integrates Fujitsu Mag EraSURE Data Degausser into its Suite of Information Technology Security Services 3QSGI Integrates Fujitsu Mag EraSURE Data Degausser into its Suite of Information Technology Security Services 4QSGI Integrates Fujitsu Mag EraSURE Data Degausser into its Suite of Information Technology Security Services 5
(Date:1/15/2014)... 2014  Bill Jacobs Automotive, a group of car dealerships headquartered ... the Heartland Blood Center and offering free oil change coupons ... place Saturday, Jan. 18 at the Bill Jacobs Cadillac and ... (Photo: http://photos.prnewswire.com/prnh/20140115/MN46637 )  The Bill Jacobs ...
(Date:1/15/2014)... Jan. 15, 2014   Niagara Thermal Products is ... Buffalo BioBlower Technologies LLC ("B3") as the critical thermal ... award from the Army Corps of Engineers.  B3 has ... all biological contaminants and destroys VOCs and other chemical ...
(Date:1/15/2014)... Calif. (PRWEB) January 15, 2014 Cynvenio, ... and management through the genomic analysis of tumor cells ... Therapy Finder™, a web-based cancer decision support application powered ... option with Cynvenio’s ClearID™ genomic test, Therapy Finder will ...
(Date:1/15/2014)... ­ RedBrick Health , a fast-growing leader in ... that EmblemHealth , the New York ... providing the RedBrick Compass health assessment, combined with the ... its members. EmblemHealth is among the first health plans ...
Breaking Biology Technology:Join the Bill Jacobs Auto blood drive and receive a free oil change 2Niagara Thermal Products LLC Selected as Critical Supplier for Buffalo BioBlower Air Purification Systems 2Cynvenio Offers New Breast Cancer Therapy Finder Application for its ClearID Breast Cancer Genomic Test 2Cynvenio Offers New Breast Cancer Therapy Finder Application for its ClearID Breast Cancer Genomic Test 3EmblemHealth Selects RedBrick Health to Power its Next-Generation Health Engagement and Behavior Change System 2EmblemHealth Selects RedBrick Health to Power its Next-Generation Health Engagement and Behavior Change System 3
... Caffeine Test Strips, to Know for Sure, Studies show that ... ... levels of caffeine, MONROVIA, Calif., Nov. 12 Ever wonder whether ... for sure,with new D+CAF, the first ever do-it-yourself caffeine test strip from,Silver ...
... MaxCyte, Inc.,the pioneer in scalable, high performance ... a live discussion with industry experts on the,challenges ... discussion is open to the industry and will ... 2:00-3:00EST., One of the respected industry experts ...
... Implementation Issues and Recommendations, BETHLEHEM, Pa., ... of Clinical Value Marketing, Infusion Systems Division ... Services for B. Braun Medical,Inc. (B. Braun), ... and services,recently represented B. Braun at the ...
Cached Biology Technology:Is Your Decaf Really Decaf? 2MaxCyte Hosts Live Discussion with Industry Experts on the Challenges in Developing Cell-Based Screening Assays for Drug Discovery 2B. Braun Directors Participate at First ISMP National Smart Pump Safety Summit 2B. Braun Directors Participate at First ISMP National Smart Pump Safety Summit 3
Sf21 Insect Cells (Live) in Max-XP Medium...
Dual-bay Dyad thermal cycler chassis, does not include the Alpha units (requires 2)...
EZ-DeWax is a one-step solution that simultanously removes paraffin from and rehydrates formalin-fixed, paraffin embedded tissue...
Artisan™ Wash Solution (x 50) Additional Information: EU regulatory status: CE US regulatory status: IVD ...
Biology Products: