Document Detail

Ecological and demographic correlates of helping behaviour in a cooperatively breeding bird.
MedLine Citation:
PMID:  23347411     Owner:  NLM     Status:  Publisher    
The evolution of cooperation is a persistent problem for evolutionary biologists. In particular, understanding of the factors that promote the expression of helping behaviour in cooperatively breeding species remains weak, presumably because of the diverse nature of ecological and demographic drivers that promote sociality. In this study, we use data from a long-term study of a facultative cooperative breeder, the long-tailed tit Aegithalos caudatus, to investigate the factors influencing annual variation in helping behaviour. Long-tailed tits exhibit redirected helping in which failed breeders may become helpers, usually at a relative's nest; thus, helping is hypothesised to be associated with causes of nest failure and opportunities to renest or help. We tested predictions regarding the relationship between annual measures of cooperative behaviour and four explanatory variables: nest predation rate, length of the breeding season, population-level relatedness and population density. We found that the degree of helping was determined principally by two factors that constrain successful independent reproduction. First, as predicted, cooperative behaviour peaked at intermediate levels of nest predation, when there are both failed breeders (i.e. potential helpers) and active nests (i.e. potential recipients) available. Second, there were more helpers in shorter breeding seasons when opportunities for renesting by failed breeders are more limited. These are novel drivers of helping behaviour in avian cooperative breeding systems, and this study illustrates the difficulty of identifying common ecological or demographic factors underlying the evolution of such systems.
Ben J Hatchwell; Stuart P Sharp; Andrew P Beckerman; Jessica Meade
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2013-1-24
Journal Detail:
Title:  The Journal of animal ecology     Volume:  -     ISSN:  1365-2656     ISO Abbreviation:  J Anim Ecol     Publication Date:  2013 Jan 
Date Detail:
Created Date:  2013-1-25     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0376574     Medline TA:  J Anim Ecol     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Copyright Information:
© 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.
Department of Animal & Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Intensity modulated radiotherapy (IMRT) combined with concurrent but not adjuvant chemotherapy in pr...
Next Document:  Medical Humanities: a question of style.