In the article cited above, the authors have recently learned that one flamingo at the Philadelphia Zoo which was originally classified as female has since been reclassified as male. The demographic information relayed in this paper was based upon the earlier classification; however, the new information does not affect the results or general conclusion. Affected portions of text have been corrected, and are shown below.
Page 369, paragraph 2:
Analyses revealed age and sex demographics to exert little influence on these general effects. Indeed, no sex differences in latency were found among birds previously engaging in unipedal (Males: M = 51.548, SD = 52.098; Females: M = 21.171, SD = 7.978; t(7.292) = 1.632, P = 0.145) or bipedal resting (Males: M = 16.393, SD = 16.273; Females: M = 16.059, SD = 20.622; t(13) = .034, P = 0.973). Similarly, no relationship was found between age and latency to initiate forward locomotion across all forms of resting (r(15) = 0.025, P = 0.923).
Page 372, paragraph 1:
Finally, we conducted a series of analyses to explore the influence of sex and age on the principle variables of interest. The percent preferences for resting on one leg while in the water and on land were averaged for each bird, and an independent samples t-test compared the averages of male (M = 74.299, SD = 14.907) and female (M = 67.456, SD = 20.624) birds. This analysis failed to yield significant differences in tendency to engage in unipedal resting between the sexes (t(15) = 0.774, P = 0.451). Similarly, no differences were obtained between the side preference indices of males (M = −0.433, SD = 0.147) and females (M = 0.039, SD = 0.378) (t(15) = −0.576, P = 0.573). Age, likewise, proved unrelated to a bird's average tendency to rest on one leg (r(15) = −0.152, P = 0.560), or side preference index (r(15) = −0.231, P = 0.372).