Crognier E, Baali A, Hilali M-K, Villena M, Vargas E
UMR6578 du CNRS et Université de la Méditerranée, Faculté de Médecine, 27 bld Jean Moulin-- 13385 Marseille Cedex 05, France.
Am J Hum Biol. 2006 May-Jun;18(3):325-34. doi: 10.1002/ajhb.20499.
Moroccan Berbers and the Bolivian Aymara are two unrelated peasant groups living in adverse environments with a still rather traditional agriculture. Precarious life conditions may be responsible for the importance given to male labor and hence for the cultural preference conferred on male descent. This preference, expressed in the social valorization of sons to the detriment of daughters, is more emphasized if the socioeconomic status of the family is lower. Interpreted according to the cost/benefit approach of Fisher (1958 Genetical Theory of Natural Selection, New York: Dover) of variations in the sex ratio and to its later developments (Trivers and Willard 1973 Science 179:90-91; Trivers 1985 Social Evolution, Menlo Park: Benjamin/Cummings; Hewlett 1991 J. Anthropol. Res. 47:1-37; Smith 1993 Ethol. Sociobiol. 14:39-44), these cultural characteristics could determine that parents bias the care allocated to their progeny in favor of sons, to the detriment of daughters. This could eventually affect their respective survival and finally modify the offspring tertiary sex ratio. This study compares differences in survival as indicators of parental care according to a child's sex and across three economic strata: poor, medium, and high. The Moroccan data express no other sex differences in survival than an advantage for daughters during the preweaning period in the medium and high strata. Within the same sex and across economic strata, a greater mortality between age 10-20 years is observed for boys of the poorest stratum. The Aymara data do not show sex differences by economic stratum, except for an advantage to daughters between birth and 5 years in the medium group, and no survival differences within the same sex across economic strata. These results suggest either that despite the social valorization of male progeny no differences in parental care according to sex occur, or that their magnitude is not great enough to contrast the survival of sons and daughters.
摩洛哥柏柏尔人和玻利维亚艾马拉人是两个没有亲缘关系的农民群体，他们生活在恶劣的环境中，农业仍相当传统。不稳定的生活条件可能导致男性劳动力受到重视，从而使男性后裔在文化上更受青睐。这种偏好表现为社会对儿子的重视甚于女儿，如果家庭的社会经济地位较低，这种偏好就会更加明显。根据费希尔（1958年，《自然选择的遗传理论》，纽约：多佛出版社）关于性别比例变化的成本/收益方法及其后来的发展（特里弗斯和威拉德，1973年，《科学》179:90 - 91；特里弗斯，1985年，《社会进化》，门洛帕克：本杰明/卡明斯出版社；休利特，1991年，《人类学研究杂志》47:1 - 37；史密斯，1993年，《动物行为与社会生物学》14:39 - 44）来解释，这些文化特征可能会使父母在分配对后代的照料时偏向儿子，而不利于女儿。这最终可能会影响他们各自的生存，并最终改变后代的三级性别比例。本研究比较了根据孩子性别以及三个经济阶层（贫困、中等和富裕）划分的生存差异，以此作为父母照料的指标。摩洛哥的数据表明，除了在中等和富裕阶层断奶前女儿具有生存优势外，在生存方面不存在其他性别差异。在相同性别且跨越经济阶层的情况下，最贫困阶层的男孩在10至20岁之间的死亡率更高。艾马拉的数据没有显示出按经济阶层划分的性别差异，除了在中等群体中女儿在出生至5岁之间具有优势，并且在相同性别且跨越经济阶层的情况下不存在生存差异。这些结果表明，要么尽管社会重视男性后代，但在父母照料方面不存在性别差异，要么这种差异的程度不足以使儿子和女儿的生存形成对比。
