Featured Research

from universities, journals, and other organizations

Cheats of the bird world: Cuckoo finches fool host parents

Date:
September 24, 2013
Source:
University of Exeter
Summary:
Cuckoo finches that lay more than one egg in their victims' nests have a better chance of bamboozling host parents into fostering their parasitic young, a study has found.

Cuckoo finch eggs have adapted to different hosts.
Credit: Claire Spottiswoode

Cuckoo finches that lay more than one egg in their victims' nests have a better chance of bamboozling host parents into fostering their parasitic young, a study has found.

Dr Martin Stevens from the University of Exeter and Dr Claire Spottiswoode from the University of Cambridge, with Dr Jolyon Troscianko at the University of Exeter, demonstrated that when African cuckoo finch females lay more than one egg in the same nest of their African tawny-flanked prinia hosts, the foster parents find it harder to tell their own eggs from the imposter's.

The host is therefore less likely to reject the parasite's eggs, such that the parasitic chick is raised for free at the host's expense. This helps to explain why female cuckoo finches commonly lay more than one egg in the same host nest.

Host parents often have difficulty in distinguishing parasitic eggs from their own because cuckoo finches lay eggs that beautifully mimic those of their hosts. Such mimicry has evolved to combat egg rejection by picky parents who remove foreign eggs from their nests.

Egg rejection depends on hosts accurately discriminating parasitic eggs from their own. To do so they must first carry out the sensory task of detecting small differences in egg colours and patterns between their eggs and the parasite's. They must then also correctly identify which eggs are parasitic, to ensure that they don't mistakenly reject any of their own eggs. This is a cognitive task relying on an ability to process the sensory information and compare it to a memorised template of what their own eggs look like.

The presence of multiple parasite eggs in the nest causes hosts to be uncertain about which eggs belong to them and which are imposters, because these sensory and cognitive mechanisms conflict with one another.

Dr Stevens said: "Our work shows that by laying multiple eggs in each host nest, the cuckoo finch has evolved a novel strategy, in addition to egg mimicry, to defeat host defences and increase its reproductive success. Laying several eggs in a host nest causes confusion in host defences, and when combined with effective mimicry, they can outwit the hosts and help more of their young to be reared.

"In the future it would be great to know whether other brood parasites have similar strategies, and whether there is any way that hosts can fight back in the arms race against the cuckoo finch."


Story Source:

The above story is based on materials provided by University of Exeter. Note: Materials may be edited for content and length.


Journal Reference:

  1. Martin Stevens, Jolyon Troscianko, Claire N. Spottiswoode. Repeated targeting of the same hosts by a brood parasite compromises host egg rejection. Nature Communications, 2013; 4 DOI: 10.1038/ncomms3475

Cite This Page:

University of Exeter. "Cheats of the bird world: Cuckoo finches fool host parents." ScienceDaily. ScienceDaily, 24 September 2013. <www.sciencedaily.com/releases/2013/09/130924113450.htm>.
University of Exeter. (2013, September 24). Cheats of the bird world: Cuckoo finches fool host parents. ScienceDaily. Retrieved October 1, 2014 from www.sciencedaily.com/releases/2013/09/130924113450.htm
University of Exeter. "Cheats of the bird world: Cuckoo finches fool host parents." ScienceDaily. www.sciencedaily.com/releases/2013/09/130924113450.htm (accessed October 1, 2014).

Share This



More Plants & Animals News

Wednesday, October 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Newsy (Sep. 30, 2014) A new study published by the World Wide Fund for Nature found that more than half of the world's wildlife population has declined since 1970. Video provided by Newsy
Powered by NewsLook.com
Dolphins Might Use Earth's Magnetic Field As A GPS

Dolphins Might Use Earth's Magnetic Field As A GPS

Newsy (Sep. 30, 2014) A study released Monday suggests dolphins might be able to sense the Earth's magnetic field and possibly use it as a means of navigation. Video provided by Newsy
Powered by NewsLook.com
How To Battle Stink Bug Season

How To Battle Stink Bug Season

Newsy (Sep. 30, 2014) Homeowners in 33 states grapple with stink bugs moving indoors at this time of year. Here are a few tips to avoid stink bug infestations. Video provided by Newsy
Powered by NewsLook.com
California University Designs Sustainable Winery

California University Designs Sustainable Winery

Reuters - US Online Video (Sep. 27, 2014) Amid California's worst drought in decades, scientists at UC Davis design a sustainable winery that includes a water recycling system. Vanessa Johnston reports. Video provided by Reuters
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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