The Evolutionary Roots of Familial Altruism: Paternity Uncertainty Shapes Patterns of Kindness
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F25%3A10499782" target="_blank" >RIV/00216208:11310/25:10499782 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Is2-vjnN50" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Is2-vjnN50</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1177/14747049251357493" target="_blank" >10.1177/14747049251357493</a>
Alternative languages
Result language
angličtina
Original language name
The Evolutionary Roots of Familial Altruism: Paternity Uncertainty Shapes Patterns of Kindness
Original language description
We investigated how paternity uncertainty (PU) shapes perceptions of familial kindness. We predicted that relatives with lower PU would be rated as kinder than those with higher PU. A total of 9,128 participants rated the kindness of specific relatives in their families. Main analyses focused on parents and maternal/paternal grandparents, who differ in their typical levels of PU. Siblings were included for broader within-family comparisons, while step-relatives, all having identical (maximal) PU, served as negative controls. Controlling for sex, age, and random effects of raters and targets, results supported PU predictions: PU showed a negative correlation with rated kindness (beta = -0.148, t((31,910)) = -6.23, p < 0.001, with the full model (including PU) significantly outperforming a reduced model (chi(2)((2)) = 42.84, p < 0.001). Post-hoc tests revealed significant differences between adjacent PU levels (0 vs. 1: p < 0.001, d = 0.15; 1 vs. 2: p = 0.0002, d = 0.08). Mothers and maternal grandmothers (no PU) were rated the kindest, while the paternal grandfather (two PU) was rated lowest. Daughters consistently rated their biological parents higher than sons, possibly reflecting lower PU through female offspring. Maternal grandfathers were rated kinder than fathers, despite identical PU, perhaps due to redirected investment by non-reproducing elders. Furthermore, mothers were rated kinder than maternal grandmothers, possibly due to "insider knowledge" of their children's paternity. Step-relatives showed minimal variation, suggesting that observed differences among biological kin reflect genetic relatedness and PU, rather than non-genetic factors. Overall, our findings support kin selection theory and suggest that paternity uncertainty subtly yet systematically shapes perceptions of familial kindness.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10602 - Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology
Result continuities
Project
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Continuities
S - Specificky vyzkum na vysokych skolach<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2025
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Evolutionary Psychology
ISSN
1474-7049
e-ISSN
1474-7049
Volume of the periodical
23
Issue of the periodical within the volume
3
Country of publishing house
US - UNITED STATES
Number of pages
16
Pages from-to
14747049251357493
UT code for WoS article
001526801000001
EID of the result in the Scopus database
2-s2.0-105010975137