Alexandra Alonzo

Kateri Broussard

Alana Pontrelli

Evolutionary Psychology, 452

Dr. Mills

Sex Differences Panel Presentation Summary

 

Nesse, R.M., Silverman,A., & Bortz, A.  (1990).  Sex Differences in Ability to Recognize

Family Resemblance.  Ethology and Sociobiology.  11, 11-21.

 

     In the article that we chose, “Sex Differences in Ability to Recognize Family Resemblance”, the authors, Nesse, Silverman, and Bortz (1990) examined whether men or women are better at judging family resemblance.  Specifically, they studied sex differences in the ability to recognize resemblance between parents and their children. 

The authors were looking for a previously unstudied question in which folk and evolutionary psychologists would make opposite, yet testable predictions.  They expected the folk psychologists to predict that women would be better, while they expected the evolutionary psychologists to predict men to be better at recognizing family resemblance.  Indeed, folk and evolutionary psychologists did respond to the study with these opposite predictions. 

     The authors attained the prediction of the folk psychologists by randomly approaching people at and outdoor art fair in which 64 out of 65 people thought “women would be superior at guessing” (Nesse, Silverman, & Bortz, 1990, 12).  The most common reason given for this prediction was the belief that “women tend to be better than men at social tasks” (Nesse, Silverman, & Bortz, 1990, 12).  

     However, the authors gathered this prediction of the evolutionary psychologists at a conference.  Nineteen evolutionary psychologists were asked, “Would you predict that men are better, worse, or the same as women at the task of judging the relatedness of adults and children from photographs?” (Nesse, Silverman, & Bortz, 1990, 12).  In response to the question, 13 out of 19 predicted that men would be better at judging this task.  Several reasons were given for this prediction.  First was the problem of paternity confidence.  They also mentioned that natural selection might or might not have been able to shape a specialized ability to recognize kin.

     Since the authors chose to study a previously unanswered question, it is important to note that the question of possible sex differences in relation to the ability to recognize family resemblance of parents and children is an extension of current research in evolutionary psychology.  The authors came up with four main reasons for this interest in sex differences in evolutionary psychology.  First, Hamilton’s discovery of kin selection led to increasing detection of fitness benefits and they are linked to the ability to distinguish kin from non-kin.  Also, since evolutionary psychology expects that the brain is sexually dimorphic, therefore sex differences in abilities and preferences have been a research focus.  Third, evolutionary psychologists have placed a large emphasis on the importance for males to recognize which children are theirs and which are not.  Finally, evolved cognitive mechanisms may suggest that the ability to recognize family resemblance follows the Darwinian algorithm.

     Indoor photographs were taken of over 200 Caucasians.  All photographs were of individual parents and their children, ages 6 months to 18 years.  Only their head and neck were visible in these photographs.  A randomization process was used to create 80 initial test items.  Half of these photographs were of related parent and child, while the other half were of unrelated parent and child.  These randomized photographs were used in a preliminary study to choose 24 items for the final test.  The final test was then divided into four subsections with six items each.  They were set up as father/daughter, father/son, mother/daughter, and mother/son.  Half of these photographs were of actual relatives and the other half was not.  These photographs were placed in a scrapbook in random order.  Eight additional single photos were added at the end of the test to assess the ability to recall faces.  Four of these had been seen before in the test book, and the other four had not. The 200 male and female subjects used were motivated by a $50 prize if they had the best score.  Subjects were asked to mark “yes” or “no” if they believed that the parent child pair they were seeing were related.

     The 200 subjects included 92 men and 108 women ranging in age from 15 to 78 years.  The main ANOVA showed no significant main effect for sex rater.   Any difference between women and men was small, but a few women did have a superior ability to recognize family resemblance.  Pairs of photos that included a mother were easier to judge than those that included a father, but no similar effect was seen for the sex of child.  Sex of rater interacted significantly with the sex of child.  Men were better at judging the relatedness of sons, and women were better at judging the relatedness of daughters.  There was no similar interaction between sex of rater and sex of parent.  Women had a superior ability to recognize faces they had seen earlier in the test, but this correlated weakly with the ability to recognize family resemblance.  The ability to recognize family resemblance was unrelated to the rater’s age, marital status, number of children, number of siblings, or years of education.

     The experimenters found that overall men and women have the equal ability to recognize familial resemblance from photographs of faces. Both sexes also found it to be easier to identify resemblance between mothers and children than between fathers and children. One explanation for this would be that facial features of children are more similar to men than women. This supports the idea of distortion and deception of mothers who have the tendency to claim that children resemble the father more so than the mother so that the father will then claim paternity.

     In addition, it was found that both sexes were better able to judge resemblance of children of their own sex. The researchers also state that contrary to the expectations of the individuals who heard about this study, the ability to judge resemblance is not influenced by demographics such as age, number of children, education, or marital status. This finding suggests that an individual’s ability to judge familial resemblance does not improve with experience. The experimenters propose that this ability may be a fixed aspect of social intelligence, much like the capability to remember faces.

     The main finding of this study- the ability to recognize family resemblance does not differ between the sexes- was not predicted or expected by either evolutionary or folk psychologists. The folk psychology prediction, that women have greater ability to recognize resemblance, is a generalization that women are better at social tasks.  This is a common and consistent error among humans.

     The idea made by evolutionary psychologists, that men would be better at recognizing family resemblance, was also incorrect. The researchers stated that this could have several explanations. The first would be that many of the individuals asked did not properly analyze the question and spent only a few moments on the question before giving their answer. Another possibility is that evolutionists seem to consider the aspect of “paternity confidence” and leave out other factors that may have an affect.

     One primary error that the researchers did not study was the failure to analyze how natural selection would shape this sexual dimorphism. Even if one sex would receive more benefits it does not seem likely that natural selection would favor one sex. The costs of maintaining this ability is small and it is beneficial to both sexes. Therefore, it was concluded that sex differences would not have resulted from natural selection.


Alexandra Alonzo

Kateri Broussard

Alana Pontrelli

Sex Differences Panel Presentation Outline

 

Nesse, R.M., Silverman,A., & Bortz, A.  (1990).  Sex Differences in Ability to Recognize

Family Resemblance.  Ethology and Sociobiology.  11, 11-21.

 

 

Introduction

A. Testable Predictions

  1. Authors examine the question of whether men or women are better at recognizing family resemblance between parents and children

a.   They expected folk psychologists and evolutionary psychologists to predict opposite.

b.      Expected folk psychologists to predict women to do better

c.       Expected evolutionary psychologists to predict men to do better

 

B. Folk Psychologists

A.     Approached people at an outdoor fair

1.      64 out of 65 people thought women would be superior at guessing pairs

2.      Predicted women would be better at recognizing family resemblance

3.      Based on belief that women tend to be better than men at social tasks

 

C. Evolutionary Psychologists

A. Approached people psychology conference

1.      Asked to make a prediction of whether men or women would do better at recognizing family resemblance.

2.      13 out of 19 though men would do better

3.      One reason is the problem of paternity confidence. 

4.      Another reason given was that natural selection might or might not have been able to shape a specialized ability to recognize kin.

 

D. Background Information

  1. Past Research

a. This topic is an extension of current research in evolutionary psychology

b.      Hamilton’s discovery of kin selection has led to growing recognition of the ability to distinguish kin from non-kin.

  1. Importance

a.       Sex differences in abilities and preferences have been a research focus in evolutionary psychology

b.      Evolutionary psychologists have placed a large emphasis on the importance for males to recognize which children are theirs and which are not.

c.   Evolved cognitive mechanisms may suggest that the ability to recognize family resemblance follows the Darwinian

 

E. Methods

1.   Materials

            a.    200 Caucasian parent/child photographs

            b.    80 initial test items were used

c.       ½ were related parent/child, ½ were unrelated parent/child

d.      24 items used for final test

e.       4 subsections w/ six items each

      2.     Photographs used

a.    father/daughter

b.    father/son

c.       mother/daughter

d.      mother/son

e.       only ½ were related

f.        8 additional single photos were added to asses the ability to recall faces

g.       4 had been seen before, 4 hadn’t been seen before

  1. Subjects

a.       200 subjects (92 males, 108 females)

b.       motivated by a $50 prize if they obtained the highest score

c.       subjects asked to mark “yes” or “no” if they believed the parent child pair they were seeing were related

 

F. Results

              1.ANOVA showed no significant main effect for sex rater

              2. Any difference between women and men was small, but a few women did have a superior ability to recognize family resemblance

              3. Pairs of photos that included a mother were easier to judge than those that included a father, but no similar effect was seen for the sex of child

             4. Sex of rater interacted significantly with the sex of child. 

             5. Men were better at judging the relatedness of sons, and women were better at judging the relatedness of daughters 

            6. There was no similar interaction between sex of rater and sex of parent 

            7. Women had a superior ability to recognize faces they had seen earlier in the test, but this correlated weakly with the ability to recognize family resemblance 

            8. The ability to recognize family resemblance was unrelated to the rater’s age, marital status, number of children, number of siblings, or years of education

 

G. Findings

1. both sexes were equally able to identify familial resemblance from photographs of faces

2. both sexes were better able to judge the resemblance between mothers and children

a. children have similar facial features to their mother

b. supports idea of deception and distortion

 

3. each sex is better able to judge family resemblance for their own sex

           

H. Demographics

1.      abilities not influenced by

a.       age

b.      number of children

c.       number of siblings

d.       education

e.       marital status

 

2.   may be an aspect of social intelligence

 

I. Critique of Folk Psychology

1. generalization that women tend to be better at social tasks

            2. very common and consistent error

 

J. Critique of Evolutionary Psychology

1. Two main errors:

a. many individuals asked only spent a few moment on the wuestion

b. evolutionists seem to consider importance of “paternity confidence”  and ignore other factors

 

K. Did natural selection shape sex differences of the ability to identify familial relations?

1.  sex differences would not result from natural selection

                        a. costs of maintaining the mechanism is relatively small

                        b. some benefits to both sexes