Related Experiment Video
Updated: Jun 12, 2026
04:10
Visually Sexing Loggerhead Shrike (Lanius Ludovicianus) Using Plumage Coloration and Pattern
Published on: March 8, 2020
Kinship affects investment by helpers in a cooperatively breeding bird
Ki-Baek Nam1, Michelle Simeoni, Stuart P Sharp
1Evolution and Behaviour Group, Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK. k.b.nam1002@gmail.com
Proceedings. Biological Sciences
|June 11, 2010
Summary
In cooperative breeding, helpers in long-tailed tits adjust their care based on relatedness. This study shows increased helping behavior correlates with closer genetic kinship, supporting kin selection theory.
Area of Science:
- Behavioral Ecology
- Evolutionary Biology
- Ornithology
Background:
- Cooperative breeding systems involve individuals helping raise young that are not their own.
- The evolutionary drivers, particularly kin selection versus direct benefits, are debated.
- Helpers potentially adjust effort based on relatedness to maximize indirect fitness benefits.
Purpose of the Study:
- To test if helper provisioning effort in long-tailed tits (Aegithalos caudatus) correlates with relatedness to broods.
- To investigate the role of kin selection in shaping helping behavior in a cooperative vertebrate.
Main Methods:
- Utilized a 14-year field study of long-tailed tits.
- Characterized relatedness using both pedigree data and microsatellite genotypes.
- Analyzed the correlation between helper provisioning effort and relatedness estimates.
Main Results:
- Helper provisioning effort positively correlated with relatedness to the brood.
- Both pedigree and genetic relatedness estimates supported this finding.
- Alloparental investment increased with increasing relatedness to recipients of care.
Conclusions:
- Kin selection plays a critical role in guiding helper investment decisions in long-tailed tits.
- Evidence supports fine-scale adjustment of helping effort based on genetic relatedness.
- Findings contribute to understanding the evolution of cooperation in vertebrate societies.
Related Concept Videos
00:57Inclusive Fitness
Most altruistic behavior—in which one animal helps another at a cost to themselves—occurs between relatives. Scientists think these altruistic behaviors evolved because they increase the inclusive fitness of the animal providing help.
01:20Mate Choice
Mate choice—the decision about whom to mate with—is a type of natural selection, since animals must reproduce to pass down their genes. Mate choice is also called intersexual selection because the behavior occurs between the sexes.
00:55Parental Care
Many animals exhibit parental care behavior, including feeding, grooming, and protecting young offspring. Parental care is universal in mammals and birds, which often have young that are born relatively helpless. Several species of insects and fish, as well as some amphibians, also care for their young.
02:29Hybrid Zones
Hybrid zones are narrow regions where two closely related species interact, mate, and produce hybrids. Relative to either parent species, hybrids may possess distinct phenotypic or genetic differences that impact their survival and reproductive success. The genetic variances introduced by hybridization influence species diversity and speciation processes within the hybrid zone.Gene flow and natural selection are evolutionary mechanisms that shape the outcome of a hybrid zone. Gene flow...
00:49Complementation Tests
A complementation test is a simple cross to identify whether the two mutations are located on the same gene or different genes. It was first performed by Edward Lewis in the 1940s while working on fruit flies. He developed the test to identify the location and arrangement of different mutations on chromosomes.
Organisms heterozygous for different mutations are crossed pairwise in all combinations. If present on different genes, the mutations can complement each other by providing the missing...
Organisms heterozygous for different mutations are crossed pairwise in all combinations. If present on different genes, the mutations can complement each other by providing the missing...
01:03Altruism
Altruistic behaviors are “unselfish” behaviors—those that help another individual at the expense of the individual carrying out the behavior. Despite the negative consequences for the altruistic animal, these behaviors are thought to have evolved for several reasons.