Figure 1.
Annual changes in testosterone plasma levels of adult Greater Rhea males (solid line-filled circles) compared with juvenile rhea males (dashed line-empty circles), showing the differences between April and September (*).
# Shows differences between April-May and August-January in Greater Rhea adult males. Results are expressed as mean ± standard error. Adult males n = 6, juvenile males (April n = 3) and (September n = 2); * and # denote p<0.01.
Figure 2.
Individual profiles of testosterone and reproductive behaviors in Greater Rhea adult males.
Annual changes in testosterone plasma levels of adult males 1 to 6 (black squares-dotted line). The reproductive behaviors: courtship (black circles-dashed line) and incubation (grey circles-grey solid line) were only observed during the reproductive period (August to January). Nest building is indicated with #, whereas the first egg detected in each pen is indicated by ♦. Arrows (↓) indicate the presence of two reproductive behaviors (courtship and incubation) on the same day. Incubation behavior for one month or more is indicated with clovers (♣).
Figure 3.
Annual changes in 17β-estradiol plasma levels of Greater Rhea adult females (solid line-filled circle) compared with juvenile rhea females (dashed line-empty circle), showing the differences in November (*).
# shows differences between April-July and September-January in Greater rhea adult females. Results are expressed as mean ± standard error; adult females n = 11, chick females n = 4; * and # denote p<0.01.