Helping decisions and kin recognition in long-tailed tits: is call similarity used to direct help towards kin?

Leedale, AE; Lachlan, RF; Robinson, EJH; Hatchwell, BJ

Abstract

Most cooperative breeders live in discrete family groups, but in a minority, breeding populations comprise extended social networks of conspecifics that vary in relatedness. Selection for effective kin recognition may be expected for more related individuals in such kin neighbourhoods to maximize indirect fitness. Using a long-term social pedigree, molecular genetics, field observations and acoustic analyses, we examine how vocal similarity affects helping decisions in the long-tailed tit Aegithalos caudatus. Long-tailed tits are cooperative breeders in which help is typically redirected by males that have failed in their own breeding attempts towards the offspring of male relatives living within kin neighbourhoods. We identify a positive correlation between call similarity and kinship, suggesting that vocal cues offer a plausible mechanism for kin discrimination. Furthermore, we show that failed breeders choose to help males with calls more similar to their own. However, although helpers fine-tune their provisioning rates according to how closely related they are to recipients, their effort was not correlated with their vocal similarity to helped breeders. We conclude that although vocalizations are an important part of the recognition system of long-tailed tits, discrimination is likely to be based on prior association and may involve a combination of vocal and non-vocal cues.

Citation

Leedale, A., Lachlan, R., Robinson, E., & Hatchwell, B. (2020). Helping decisions and kin recognition in long-tailed tits: is call similarity used to direct help towards kin?. Philosophical Transactions B: Biological Sciences, 375(1802), https://doi.org/10.1098/rstb.2019.0565

• Journal Article Type: Article
• Publication Date: May 18, 2020
• Deposit Date: Dec 6, 2022
• Journal: Philosophical Transactions of the Royal Society B: Biological Sciences
• Print ISSN: 0962-8436
• Electronic ISSN: 1471-2970
• Publisher: The Royal Society
• Volume: 375
• Issue: 1802
• DOI: https://doi.org/10.1098/rstb.2019.0565
• Publisher URL: https://doi.org/10.1098/rstb.2019.0565