Featured Research

from universities, journals, and other organizations

Gangster birds running protection racket give insight into coevolution

Date:
November 18, 2010
Source:
Biotechnology and Biological Sciences Research Council (BBSRC)
Summary:
Like gangsters running a protection racket, drongos in the Kalahari Desert act as lookouts for other birds in order to steal a cut of their food catch. The behavior may represent a rare example of two species evolving from a parasitic to a mutualistic relationship.

Andy Radford (University of Bristol) and a pied babbler in the Kalahari.
Credit: © Matthew Bell, University of Cambridge

Like gangsters running a protection racket, drongos in the Kalahari Desert act as lookouts for other birds in order to steal a cut of their food catch. The behaviour, revealed in research funded by the Biotechnology and Biological Sciences Research Council (BBSRC) published in Evolution and reported in Nature's Research Highlights, may represent a rare example of two species evolving from a parasitic to a mutualistic relationship.

The team from the Universities of Bristol, Cambridge and Cape Town showed that victimised pied babblers gained a mitigating benefit from the presence of thieving drongos because, by keeping watch for predators, the drongos allowed the babblers to focus on foraging and so catch more insects.

Many apparently harmful parasites seem to be tolerated by their hosts and the provision of compensatory benefits to victims could underpin a range of host-parasite relationships. The insight the research provides into complex co-evolution between species gives scientists a valuable way of understanding other important relationships, such as those between drugs and bacteria and between pathogens and hosts.

Dr Andrew Radford, who led the research funded through a BBSRC David Phillips Fellowship, said: "Because drongos are parasitic birds who swoop in to steal food from other species, you'd expect them to keep a low profile while waiting. Rather surprisingly, however, drongos perched above foraging babblers advertise their presence by issuing a call called a 'twank' every 4 or 5 seconds.

"When we played back these 'twank' calls to a babbler group, we found that they spread out over a larger area and lifted their heads less often, indicating that they were less fearful of predators when they thought a drongo was keeping watch. We think that drongos have evolved to alert babblers to their presence because helping the group forage more effectively leads to more frequent opportunities for theft."

Drongos have an ingenious way of catching food: by crying wolf about the presence of predators, they scare other animals into dropping their catch, which the birds then pounce on. This research indicates that pied babblers have evolved to tolerate the drongos giving false warnings and stealing some of their hard-earned gains in exchange for the chance to forage in relative safety when a drongo is keeping watch.

Dr Radford continued: "Like any good gangster, as well as lying and stealing, the drongos also provide protection by mobbing aerial predators and giving true alarm calls on some occasions. But, despite all of the useful services drongos provide, the foraging birds are still more responsive to calls from other babblers. It seems likely that the babblers simply don't trust the drongo mafia as much as their own flesh and blood."

Professor Douglas Kell, BBSRC Chief Executive said: "Evolutionary arms-races, including those between parasites and their hosts, and plants and animals and the diseases that they suffer, underlie a whole range of socially and economically important areas of biology. From drug and pesticide resistance to the biodiversity of ecosystems, deepening our understanding how a range of organisms have evolved into complex relationships will help us address important social issues in a smarter, more holistic way."

The research was carried out with the support of the Percy FitzPatrick Institute of African Ornithology at the University of Cape Town, Magdalene College, Cambridge, and the EU.


Story Source:

The above story is based on materials provided by Biotechnology and Biological Sciences Research Council (BBSRC). Note: Materials may be edited for content and length.


Journal Reference:

  1. Andrew N. Radford, Matthew B. V. Bell, Linda I. Hollén, Amanda R. Ridley. Singing for Your Supper: Sentinel Calling by Kleptoparasites Can Mitigate the Cost to Victims. Evolution, 2010; DOI: 10.1111/j.1558-5646.2010.01180.x

Cite This Page:

Biotechnology and Biological Sciences Research Council (BBSRC). "Gangster birds running protection racket give insight into coevolution." ScienceDaily. ScienceDaily, 18 November 2010. <www.sciencedaily.com/releases/2010/11/101118083905.htm>.
Biotechnology and Biological Sciences Research Council (BBSRC). (2010, November 18). Gangster birds running protection racket give insight into coevolution. ScienceDaily. Retrieved August 1, 2014 from www.sciencedaily.com/releases/2010/11/101118083905.htm
Biotechnology and Biological Sciences Research Council (BBSRC). "Gangster birds running protection racket give insight into coevolution." ScienceDaily. www.sciencedaily.com/releases/2010/11/101118083905.htm (accessed August 1, 2014).

Share This




More Plants & Animals News

Friday, August 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Visitors Feel Part of the Pack at Wolf Preserve

Visitors Feel Part of the Pack at Wolf Preserve

AP (July 31, 2014) — Seacrest Wolf Preserve on the northern Florida panhandle allows more than 10,000 visitors each year to get up close and personal with Arctic and British Columbian Wolves. (July 31) Video provided by AP
Powered by NewsLook.com
Florida Panther Rebound Upsets Ranchers

Florida Panther Rebound Upsets Ranchers

AP (July 31, 2014) — With Florida's panther population rebounding, some ranchers complain the protected predators are once again killing their calves. (July 31) Video provided by AP
Powered by NewsLook.com
Dangerous Bacteria Kills One in Florida

Dangerous Bacteria Kills One in Florida

AP (July 31, 2014) — Sarasota County, Florida health officials have issued a warning against eating raw oysters and exposing open wounds to coastal and inland waters after a dangerous bacteria killed one person and made another sick. (July 31) Video provided by AP
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) — Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins