Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

In monogamous species, a compatible partner is more important than an ornamented one

19.03.2018

The colour of bands attached to the legs of birds for individual identification does not have an effect on the birds’ behaviour, physiology, life-history or fitness. This result of a study from the Max Planck Institute for Ornithology in Seewiesen contradicts long established text-book “knowledge” and questions whether ornaments play a major role in mate choice of monogamous species.

More than 35 years ago, a study reported that leg bands of certain colours have major effects on the attractiveness of an individual and hence on mate choice. The idea sounds plausible: zebra finch males decorated with red bands are more attractive to females than males wearing green bands, because a red band amplifies the ornamental effect of the male’s beak, which is coloured deep red.


Female zebra finch and two males with red or green colour bands

Wolfgang Forstmeier / MPIO

Since the first claim, 39 studies have been published in which zebra finch males had been fitted with such colour bands. Twenty-three studies confirmed that red-banded males are superior to green-banded ones, while an additional eight studies found at least some effect on one of the “success” parameters studied.

The current study from the Department of Behavioural Ecology and Evolutionary Genetics at the Max Planck Institute for Ornithology in Seewiesen analysed the results of eight experiments in which the researchers quantified reproductive success of a total of 730 colour-banded individuals from four different captive populations.

This sample size exceeds the combined sample of all 23 publications that clearly supported the “colour-band effect” hypothesis. The researchers, however, did not find any effect of band colour on reproductive success of either males or females across all populations.

“The large sample size clearly showed that there is no effect at all”, says Wolfgang Forstmeier, who led the study. “A closer look at the statistics of the previously published studies revealed that positive results were only reported when sample sizes were small, suggesting that the results may be artefacts.”

For the researchers in Seewiesen, this finding did not come as a big surprise: a previous study from the same group found that female zebra finches chose compatible partners, and not necessarily the ones that were highly ornamented.

As zebra finches are socially monogamous and nearly every female ends up with exactly one male partner, strong preferences for highly ornamented individuals may not be favoured by selection. This may be because the costs of competition can easily exceed the benefits of choosiness when only one female can get the most beautiful male in the end.

„The pronounced individuality of mate preferences in zebra finches clearly does not result in strong selection for attractive ornaments“, says Bart Kempenaers, director of the department. Instead, brood care may be optimal if partners choose traits that ensure behavioural compatibility rather than ornamental traits.

Contact:
Dr. Wolfgang Forstmeier
Max Planck Institute for Ornithology, Seewiesen
Department of Behavioural Ecology and Evolutionary Genetics
Eberhard-Gwinner-Strasse
82319 Seewiesen
Email: forstmeier@orn.mpg.de
Tel: +49 8157 932-346

Weitere Informationen:

http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1558-5646 (Study will be online on March 19)

Dr. Sabine Spehn | Max-Planck-Institut für Ornithologie
Further information:
http://www.orn.mpg.de

More articles from Life Sciences:

nachricht Polymers get caught up in love-hate chemistry of oil and water
28.02.2020 | DOE/Oak Ridge National Laboratory

nachricht How do zebrafish get their stripes? New data analysis tool could provide an answer
28.02.2020 | Brown University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: High-pressure scientists in Bayreuth discover promising material for information technology

Researchers at the University of Bayreuth have discovered an unusual material: When cooled down to two degrees Celsius, its crystal structure and electronic properties change abruptly and significantly. In this new state, the distances between iron atoms can be tailored with the help of light beams. This opens up intriguing possibilities for application in the field of information technology. The scientists have presented their discovery in the journal "Angewandte Chemie - International Edition". The new findings are the result of close cooperation with partnering facilities in Augsburg, Dresden, Hamburg, and Moscow.

The material is an unusual form of iron oxide with the formula Fe₅O₆. The researchers produced it at a pressure of 15 gigapascals in a high-pressure laboratory...

Im Focus: From China to the South Pole: Joining forces to solve the neutrino mass puzzle

Study by Mainz physicists indicates that the next generation of neutrino experiments may well find the answer to one of the most pressing issues in neutrino physics

Among the most exciting challenges in modern physics is the identification of the neutrino mass ordering. Physicists from the Cluster of Excellence PRISMA+ at...

Im Focus: Therapies without drugs

Fraunhofer researchers are investigating the potential of microimplants to stimulate nerve cells and treat chronic conditions like asthma, diabetes, or Parkinson’s disease. Find out what makes this form of treatment so appealing and which challenges the researchers still have to master.

A study by the Robert Koch Institute has found that one in four women will suffer from weak bladders at some point in their lives. Treatments of this condition...

Im Focus: A step towards controlling spin-dependent petahertz electronics by material defects

The operational speed of semiconductors in various electronic and optoelectronic devices is limited to several gigahertz (a billion oscillations per second). This constrains the upper limit of the operational speed of computing. Now researchers from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg, Germany, and the Indian Institute of Technology in Bombay have explained how these processes can be sped up through the use of light waves and defected solid materials.

Light waves perform several hundred trillion oscillations per second. Hence, it is natural to envision employing light oscillations to drive the electronic...

Im Focus: Freiburg researcher investigate the origins of surface texture

Most natural and artificial surfaces are rough: metals and even glasses that appear smooth to the naked eye can look like jagged mountain ranges under the microscope. There is currently no uniform theory about the origin of this roughness despite it being observed on all scales, from the atomic to the tectonic. Scientists suspect that the rough surface is formed by irreversible plastic deformation that occurs in many processes of mechanical machining of components such as milling.

Prof. Dr. Lars Pastewka from the Simulation group at the Department of Microsystems Engineering at the University of Freiburg and his team have simulated such...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

70th Lindau Nobel Laureate Meeting: Around 70 Laureates set to meet with young scientists from approx. 100 countries

12.02.2020 | Event News

11th Advanced Battery Power Conference, March 24-25, 2020 in Münster/Germany

16.01.2020 | Event News

Laser Colloquium Hydrogen LKH2: fast and reliable fuel cell manufacturing

15.01.2020 | Event News

 
Latest News

New molten metal hybrid filters from TU Freiberg will make components even safer and more resistant in the future

28.02.2020 | Materials Sciences

Polymers get caught up in love-hate chemistry of oil and water

28.02.2020 | Life Sciences

Two NE tree species can be used in new sustainable building material

28.02.2020 | Architecture and Construction

VideoLinks
Science & Research
Overview of more VideoLinks >>>