Trivers-Willardova hipoteza

Abstract

The Trivers-Willard hypothesis indicates that the ratio of male and female offspring will be biased depending on the conditions of the parents. Parents in better conditions are more likely to have a son, and parents in poor conditions are more likely to have a daughter. This effect has been observed in a number of species including people, although findings are less conclusive in their case. The extended form of the hypothesis (generalised Trivers-Willard hypothesis) suggests that the biased sex ratio will be influenced by any factor that leads to differential reproductive success. This form of the hypothesis has also received notable support.