Figure 1.
Examples of (A) kin discrimination and (B) individual discrimination trials.
The target is displayed uppermost, with two alternative matches placed below. (A) A paternal line mixed-sex kin discrimination trial, with the father displayed uppermost. In this case the correct choice (daughter) is the lower-right image. (B) A male-male individual discrimination trial, in which the target and lower-left images are of the same animal.
Figure 2.
Performance on individual discrimination trials.
Mean (and SD) resemblance scores between an alternative view of the same- versus a different (and unrelated) individual and the target image, in male-male and female-female triads. A mean of zero represents chance performance. Positive values indicate that a second image of the same individual was rated as being more similar to the target animal than was an equivalently-oriented image of an unrelated individual, with higher values indicating a greater disparity in perceived similarity.
Table 1.
Results of models examining performance in the individual discrimination task.
Table 2.
Estimates of overall intercept (mean response score) in the individual discrimination (ID) and kin discrimination (KD) tasks.
Table 3.
Results of models examining performance in the kin discrimination task.
Figure 3.
Performance on kin discrimination trials.
Mean (and SD) resemblance scores between offspring versus unrelated individuals and the target image (parent), as a function of relatedness type (paternal, maternal) and the subject's level of previous experience with nonhuman primates. A mean of zero represents chance performance. Positive values indicate that the offspring image was rated as being more similar to the parental target than was the unrelated individual, with higher values indicating a greater disparity in perceived similarity.