Nikakhtar Alireza, Kirchengast Sylvia, Bazram Adel, Rafezi Zohreh
Faculty of Psychology and Education, Allameh Tabataba'i University, Tehran, Iran.
Department of Evolutionary Anthropology, University of Vienna, Djerassiplatz 1, A-1030 Vienna, Austria.
Anthropol Anz. 2024 May 26;81(2):123-133. doi: 10.1127/anthranz/2024/1787.
Higher investment in maternal than paternal aunts and uncles is explained by the "paternity uncertainty hypothesis". Regardless of laterality, however, aunts show a greater degree of investment than uncles, which is attributed to sex-specific reproductive strategies. Resemblance cues can be used as indicators of genetic relatedness. The central hypothesis of the current study was that perceived phenotypic resemblance between aunts/uncles and niblings would be associated with aunts' and uncles' investment. The association was predicted to be stronger with respect to patrilateral than matrilateral aunts and uncles and stronger with respect to patrilateral aunts than patrilateral uncles. 243 Iranians aged between 15 and 50 participated in a retrospective analysis and filled out a 52-item questionnaire focusing on the solicitude, emotional closeness, and contact frequency between aunts/uncles and their nephews/nieces. In addition, the participants had to rate their phenotypic resemblance with their aunts and uncles. Aunts' and uncles' solicitude, emotional closeness, and contact frequency were differentially expressed according to sex and laterality. Maternal aunts showed the significantly highest emotional closeness, contact frequency, and investment, while the opposite was true for paternal uncles. Moreover, investment was correlated with phenotypic resemblance. Such association was stronger for patrilateral than matrilateral aunts and uncles, and concerning solicitude it was stronger for patrilateral aunts than patrilateral uncles. The resemblance-based kin recognition mechanism among aunts and uncles was self- rather than family-referent. In conclusion, phenotypic similarity can be used as a cue to genetic kinship and is correlated with the investment of aunts and uncles. However, such associations also depend on the degree of genetic relatedness and the differential kin investment provided by each sex.
“父系不确定性假说”解释了对母系姑姑和叔叔的投资高于父系姑姑和叔叔的现象。然而，无论偏向哪一方，姑姑的投资程度都高于叔叔，这归因于特定性别的生殖策略。相似线索可用作基因相关性的指标。本研究的核心假设是，姑姑/叔叔与侄子女之间感知到的表型相似性将与姑姑和叔叔的投资相关联。预计这种关联在父系姑姑和叔叔中比在母系姑姑和叔叔中更强，在父系姑姑中比在父系叔叔中更强。243名年龄在15至50岁之间的伊朗人参与了一项回顾性分析，并填写了一份52项的问卷，该问卷聚焦于姑姑/叔叔与他们的侄子/侄女之间的关怀、情感亲密度和联系频率。此外，参与者必须对自己与姑姑和叔叔的表型相似性进行评分。姑姑和叔叔的关怀、情感亲密度和联系频率根据性别和偏向性存在差异表达。母系姑姑表现出显著最高的情感亲密度、联系频率和投资，而父系叔叔则相反。此外，投资与表型相似性相关。这种关联在父系姑姑和叔叔中比在母系姑姑和叔叔中更强，就关怀而言，在父系姑姑中比在父系叔叔中更强。姑姑和叔叔之间基于相似性的亲属识别机制是自我参照而非家庭参照的。总之，表型相似性可用作基因亲属关系的线索，并与姑姑和叔叔的投资相关。然而，这种关联也取决于基因相关性的程度以及每种性别提供的不同亲属投资。
