Abstract
Six hundred and eight students from the Faculty of Biological Sciences of Valencia (Spain) provided information about secondary sex ratio and family size of the parental, present, and projected generation. The average number of children was 3.59, 3.05, and 2.10 and the secondary sex ratio was 113.3, 101.2, and 98.6 for the parental, present, and projected generation respectively. Combination of sexes of the first two children had a significant effect in the parental and the present generations. There was no consistent association between sexes of successive and sexes of nonsuccessive children within families. The most preferred combination of sexes in the projected generation was one male-one female, and male-female was the most preferred permutation. Strong preferences for the firstborn to be male and for an alternation of sexes were also indicated.
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Abdulla, A. S., Al-Rubeai, M. A. F., and Gray, E. (1984). Desired family size and sex of children in Lybia.J. Hered. 75:76–78.
Ayala, F. J., and Falk, C. T. (1971). Sex of children and family size.J. Hered. 62:57–59.
Edwards, A. W. F. (1961). A factorial analysis of sex ratio data.Ann. Hum. Genet. 25:117–121.
Edwards, A. W. F., and Fraccaro, M. (1960). Distribution and sequences of sexes in a selected sample of Swedish families.Ann. Hum. Genet. 24:245–252.
Gray, E. (1972). Influence of sex of first two children on family size.J. Hered. 63:91–92.
Gray, E., and Bortolozzi, J. (1977). Studies of the human sex ratio and factors influencing family size in Botucatu, Brazil.J. Hered. 68:241–244.
Gray, E., and Morgan, D. K. (1976). Desired family size and sex of children.J. Hered. 67:319–321.
Gray, E., and Morrison, N. M. (1974). Influence of combinations of sexes of children on family size.J. Hered. 65:169–174.
Gray, E., Bortolozzi, J., and Hurt, V. K. (1979). Desired family size and sex of children in Botucatu, Brazil.J. Hered. 70:67–69.
Gray, E., Duckworth, D., and Nakaiima, Y. (1980). The human sex ratio and factors influencing family size in Japan.J. Hered. 71:411–415.
Gray, E., Hurt, V. K., and Oyewole, S. O. (1983). Desired family size and sex of children in Nigeria.J. Hered. 74:204–206.
Krishnan, V. (1987). Preferences for sex of children: A multivariate analysis.J. Biosoc. Sci. 19:367–376.
Loyd, R. C., and Gray, E. (1969). A statistical study of the human sex ratio.J. Hered. 60:329–331.
Park, C. B. (1978). The fourth Korean child: The effect of son preference on subsequent fertility.J. Biosoc. Sci. 10:95–106.
Pust, R. E., Newman, J. S., Senf, J., and Stotik, E. (1985). Factors affecting desired family size among preliterate New Guinea mothers.Int. J. Gynaecol. Obstet. 23:413–420.
Ruder, A. (1986). Paternal factors affect the human secondary sex ratio in interracial births.Hum. Biol. 58:357–366.
Sokal, R. R., and Rohlf, F. J. (1969). Biometry, W. H. Freeman, San Francisco.
Stern, C. (1979).Genética Humana Alhambra, Spain.
Thomas, M. H. (1951). Sex pattern and size of family.Br. Med. J 1:733–734.
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Nájera, C., Aparisi, M.L. & Gómez, F. Sex ratio and factors influencing family size in a human population from Spain. Behav Genet 22, 531–543 (1992). https://doi.org/10.1007/BF01074306
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DOI: https://doi.org/10.1007/BF01074306