The Truth about Cinderella: A Darwinian View of Parental Love

Summary of The Truth about Cinderella: A Darwinian View of Parental Love

In the book, The Truth about Cinderella: A Darwinian View of Parental Love by Daly, M., & Wilson M. (1999) the authors explain the steps leading up to their research on abuse in step-families and their methodology in doing the research. In many cultures there exists a variation of the Cinderella story in which a parent’s genetic children are favored over their step-children (p 1-4). The author’s research supported the real existence of this Cinderella effect and the authors contend that there are evolutionary reasons for this effect.


Evolutionary sexual selection adaptation (same sex/same species competition for limited resource of mating partner) comes into play when a new male partner kills the dependent children of his partner’s previous mate which allows him to more quickly produce his own children and have his genetics passed along (e.g. male lions pg. 9 and Jacanas p. 10). If a male did not do this then fewer of his children would be born compared to a male who practiced infanticide of step-children.


Infanticide of step-children is not evolutionarily adaptive if the risks outweigh the benefit which is the case in human society; but it does seem to exist in a more minor form where the scarce resource of parental attention is lavished more upon one’s genetic children than upon the genetic children of a rival. Attachment to a child would have made a male more likely to put up with the resource demands of a dependent child. Forming this bond indiscriminately with a rival’s child would have depleted the resources available for his genetic child. This would not have been advantageous to his genetic offspring and therefore his genetics would not have been passed along in a larger quantity than his rival’s (p 38-39).


The researchers analysis of existing child abuse records supports this contention since a greater percentage of all step-families in the population at large have recorded child abuse records. The number of step-families in the population at large is perhaps over estimated but if so then this indicates that the percentage of step-child abuse is even greater than the article represents.


In a Canadian municipality of 500 thousand the researchers found that 1 in 3000 pre-schoolers who lived with their genetic parents were reported for abuse but 1 in 75 pre-schoolers who lived with a step=parent were abused (p. 30). This abuse was far more likely to occur to pre-schoolers than teenagers (p. 30).

A possible flaw in the research is the existence of the Cinderella myth itself which might lead a neighbor to report possible abuse more readily if a step-parent was present. The researchers repeated their research using only fatal child abuse situations and found the same extreme rates of child abuse in step-families (p. 32).