Assignment: Encoding On Perfomance

Participants. Sixty-six women ranging in age from 17 to 28 years (Mean7SE5 18.7070.04) from varying ethnic backgrounds participated in the manipulation validation study. They were recruited from a mid-size university located in southern Ontario, Canada.

Procedure. To verify the evolutionary signifi- cance of the exposure to the sexy confederate, women were randomly assigned to one of the three conditions. In all three conditions, participants were asked to rate a color photograph of the confederate from Study 1. Specifically, they were asked to rate the woman’s level of attractiveness (cuteness) and sexiness in the photograph using a scale of 1–10 with 15not at all descriptive and 105 extremely descriptive. Participants were also asked to rate how likely, on a scale of 1 to 7 with 15 extremely unlikely and 15 extremely likely, would they

Fig. 2. Mean bitchy scores by condition (sexy vs. conservative) and

dyad (friends vs. strangers).

TABLE II. Relative Frequency of Other Negative Behavior by Experimental Condition

Type of behavior

Conservative condition

(N5 40)

Sexy condition

(N5 46)

Exchanging information 1 (2.5%) 14 (30%)

Once-overs 10 (25%) 39 (85%)

Negative verbal

comments

0 (0%) 12 (26%)

Laughed 3 (7.5%) 21 (46%)

573Intrasexual Competition Among Women

Aggr. Behav.

introduce her to their boyfriend (current or future) and how likely would they let their boyfriend (current or future) spend time alone with her. In the first condition (conservative), a photograph of the conservatively dressed confederate was provided (Fig. 1A). In the second condition (sexy-thin), a photograph of the sexy dressed confederate was provided (Fig. 1B). Finally, in the third condition (sexy-fat), a photograph of the sexy dressed con- federate was manipulated so that she appeared overweight (Fig. 1C).

Results

ANOVA was used to examine participants’ perception of the confederate from Study 1. Given the number of analyses conducted, Po.01 was again used as an indicator of statistical significance. As expected, Student–Newman–Keuls post-hoc tests confirmed that even though participants rated the conservative confederate as cuter than the other two women (F(2, 61)5 13.72, Po.001, partial Z2 5 .31), they nevertheless were less likely to introduce the sexy-thin confederate to their boyfriend (F(2, 63)5 24.98, Po.001, partial Z2 5 .44), or let him spend time alone with her (F(2, 63)5 8.81, Po.001, partial Z2 5 .22) than the sexy-fat or conservative confederate (see Table III for all Means, SE, and post-hoc comparisons). Moreover, participants also rated the sexy-thin confederate as being sexier than the sexy-fat and conservative confederates (F(2, 61)5 9.74, Po.001, partial Z2 5 .24), with the post-hoc test revealing that the mean ratings on sexy for the sexy-fat and conservative confederates were not statistically significantly different from one another. Finally, consistent with our initial hypothesis, we