Researchers from the Max Planck Institute for Ornithology in Seewiesen found evidence that both winners and losers exhibit raised testosterone levels after a conflict without an audience. Furthermore, both maintained their social status within their group.
Although the fights are naturally pretty rough, none of the combatants got seriously injured.
Image: Katharina Hirschenhauser
An informed audience determines the future social status of a male after a fight with a dominant male of another social group.
Image: Katharina Hirschenhauser
With an audience, on the other hand, this remained true for winners, but not for losers: they had neither raised testosterone levels nor were they able to maintain their dominant status within the group. Thus, informed audiences determine the future social status of a male, while testosterone plays a secondary role.
Battles for territory and mating partners are widespread in the animal world and are usually fought by males. The sex hormone testosterone thereby plays a crucial role. The concentration of this substance often rises dramatically during a fight. However, the social environment in which the rivals fight their battle can change the context and affect the role of testosterone for maintaining dominance. Experience plays a role, for instance, how often the opponents got involved in a conflict and whether they have met before. Of crucial importance can also be whether the fight is watched by spectators. Audiences can have a decisive effect on the outcome of a contest between humans, too.
With support of the Alexander-von-Humboldt Society, scientists working with Katharina Hirschenhauser from the Max Planck Institute for Ornithology in Seewiesen have been studying the influence of mixed-sex audiences on future social status after a fight. They kept quails in social groups each consisting of two males (one dominant and one subordinate) and three females. The scientists observed fights between two dominant male quails in a central arena. The members of the respective social group either were allowed to watch the fight or not. During the fighting phase, which lasted an average of seven minutes, the eventual winners attacked their rivals 29 times on average. Although the fights are naturally pretty rough, none of the combatants got seriously injured.
The winners, without exception, retained their dominant status ("the winner effect"). The losers, on the other hand, were often "beaten up" by the previously subordinate male after returning to their social group and on a long-term lost their dominant status ("the loser effect"). Where there was no audience present, however, even the losers were able to maintain their dominant status.
As expected, testosterone levels were raised after the fight when there was no audience. This happened regardless of whether the quails had won or lost. After a fight in front of an audience, though, the losers had lower testosterone levels. The winners, on the other hand, showed a similar increase to quails that had fought without an audience. In order to determine whether a change in status after losing a fight in front of an audience could be physiologically prevented, the scientists treated the losers immediately after the fight with a testosterone cream on the skin. This treatment seriously influenced the birds' aggressive behaviour: the losers were chasing the subordinate male in the group to a greater extent, which enabled them to remain dominant. This seems to indicate that testosterone is a mediator of the “winner effect” – or at the loser’s side, its lack has an influence on future success.
Dr. Sabine Spehn | Max-Planck-Institut
Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München
Second research flight into zero gravity
21.10.2016 | Universität Zürich
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences