"When partners duet, they signal to other magpie-larks that they are working as a team to defend their territory," said Dr. Michelle Hall of the Max Planck Institute for Ornithology of the new findings. "The level of precision in their duets seems to let others know how ‘good’ they are—their ability and/or motivation to cooperate for territorial defense."
Coordinated displays are widely used among animals to defend shared resources, and may signal coalition strength so that groups can assess the relative competitive ability of rivals and avoid unnecessary fights. For example, lions roar in choruses that provide information about their group’s size to intimidate rivals, as do gibbons, chimpanzees, and wolves, Hall said.
Paired Australian magpie-larks sing notes in rapid alternation to produce duets for territorial defense. One member of the pair repeatedly makes a call that sounds like ‘peewee,’ and the other responds each time with ‘wit,’ Hall said. Experiments have shown that the birds’ duets are more threatening territorial displays than songs sung solo.
However, magpie-lark pairs vary considerably in their singing skills. Highly coordinated partners create alternating notes so closely spaced that they can sound like a single bird. In contrast, others’ relatively poorer vocals often include gaps, overlaps, or irregular tempos. Yet the influence of those timing differences on the level of threat perceived by members of the birds’ listening audiences remained uncertain.
Hall and study collaborator Robert Magrath of Australian National University, Canberra, tested the function of duet precision by broadcasting coordinated and uncoordinated songs on twelve magpie-lark territories. Male magpie-larks responded most aggressively to coordinated duets, evidence that the sound of precise pairs signaled a strong coalition more likely to fend off intruders.
Longer-term partners more often produce well-coordinated duets, they found. Thus, they said, duetting talent may signal the pairs’ ongoing motivation to act collectively—the stability of their unions. Duet precision might also indicate the ability for concerted action. For instance, duet ‘tempo’ slows when partners are farther apart.
Hall said she hopes to continue exploring the magpie-larks’ duets in different contexts, to find out "whether precision of duets signals coalition quality by revealing fighting ability, or motivation, or both."
Erin Doonan | EurekAlert!
New findings help to better calculate the oceans’ contribution to climate regulation
14.11.2018 | Jacobs University Bremen gGmbH
How algae and carbon fibers could sustainably reduce the athmospheric carbon dioxide concentration
14.11.2018 | Technische Universität München
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly
The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...
09.11.2018 | Event News
06.11.2018 | Event News
23.10.2018 | Event News
14.11.2018 | Materials Sciences
14.11.2018 | Health and Medicine
14.11.2018 | Life Sciences