Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Clicking knees are antelopes’ way of saying ‘back off’

04.11.2008
Knee clicking can establish mating rights among antelopes. A study of eland antelopes, published in the open access journal BMC Biology, has uncovered the dominance displays used by males to settle disputes over access to fertile females, without resorting to genuine violence.

Jakob Bro-Jørgensen from the Zoological Society of London and Torben Dabelsteen from the University of Copenhagen studied antelopes within a 400km2 area of Kenya.

They found that the males (bulls) use a selection of signals to make competitors aware of their fighting ability, based on three different factors, body size, age and aggression. According to Bro-Jørgensen, “Rivals often use signals to broadcast their fighting ability and thereby settle conflicts without incurring the high costs associated with actual fighting”.

As well as the knee clicks, which are shown to be a reliable indicator of body size, the researchers found that the size of a bull’s dewlap is related to age. The authors said, “Age is a good proxy for fighting experience and may also demonstrate that a bull has ‘nothing to lose’ and will therefore be a more risk-prone and dangerous adversary”.

Finally, hair darkness reflects yet another underlying variable, most likely androgen-related aggressiveness. All of these indicators serve the useful purpose of facilitating assessment by a bull’s rivals and avoiding wasteful conflict.

The antelopes’ knee clicks, which can be heard several hundred metres away, are thought to be produced by a tendon slipping over one of the leg bones and, according to the authors, this can explain why they correlate with body size, “The tendon in this case behaves like a string being plucked, and the frequency of the sound from a string correlates negatively with both its length and diameter. Thus, most importantly, depth of the sound is predicted to increase with skeletal measures”.

Graeme Baldwin | alfa
Further information:
http://www.biomedcentral.com/

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>