Related Experiment Video
Updated: Oct 4, 2025

Using a Comparative Species Approach to Investigate the Neurobiology of Paternal Responses
Published on: September 19, 2011
Preferences for a mixed-sex composition of offspring: A multigenerational approach
1Princeton University.
Abstract:
Parents with two boys or two girls are more likely to have a third child than those with a 'sex mix'. However, little is known on whether these 'mixed-sex preferences' extend beyond the nuclear family. This study leverages the random variation in sex at birth to assess whether the sex of nieces and nephews, in combination with own children, matters for fertility choices. Using three-generational data from the US Panel Study of Income Dynamics (PSID), I show that extended families (including grandparents, their children, and their grandchildren) are collectively more likely to have three or more grandchildren when lacking sex mix, whether the first two grandchildren are siblings or cousins. I explore the pathways for these offspring sex preferences, finding support for a preference for an uninterrupted line of male descendants. This multigenerational approach also contributes a new estimation strategy that causally estimates the effects of family sizes on outcomes beyond fertility.
Related Concept Videos
Natural Selection and Mating Preferences
Females, due to their biological roles in conception, pregnancy, and nursing,...
Trihybrid Crosses
Some of Mendel’s crosses examined three pairs of contrasting characteristics. Such a cross is called a trihybrid cross. A trihybrid cross is a combination of three individual monohybrid crosses. For example, plant height (tall vs. short), seed shape (round vs. wrinkled), and seed color (yellow vs. green).
The F1 generation plants of a trihybrid cross are heterozygous for all three traits and produce eight gametes. Upon self-fertilization, these gametes have an equal...
Law of Segregation
The Ratio of X Chromosome to Autosomes
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female...
Law of Independent Assortment
Dihybrid Crosses

