Figure 2.

Mean (±SE) testis volume (a), follicle diameter (b), and molt scores of primary flight (c) and body feathers (d) of male and female house sparrows procured every month from the wild or kept in the out door aviary from December through November. In captives, peak testicular growth was delayed by 4 weeks (a), and follicular growth was attenuated (b). Also, the shape of curve reflecting ovarian growth and regression was difference between wild and captive sparrows (b). Asterisks show significant difference (P < 0.05) in the response between the two conditions.