The effects of testosterone (T) on the acoustic features of the ''rusty-gate'' call of the grey partridge, a non-oscine bird, were studied in 24 males kept in semi-natural conditions. Half of them were implanted subcutaneously with T propionate in Silastic tubes at 10 weeks of age, the remaining were sham operated as controls. After one month implanted males showed significantly higher T levels than controls, while treatment did not affect body size. Individual recordings of calls were analysed and accurate measurements were taken by a digital spectrograph. The duration of calls was significantly greater in T-males than in controls. A similar lengthening has been described in nature in spring, when plasma levels of androgens rise. The frequencies of the most intense portion of the call ranged more widely and had a lower minimum in T-males than in controls, suggesting an hormonal control on call system at the peripheral/central level. In conclusion T affects specific temporal and frequency features of the male calls. The relationship between T and call structure could enable females to assess quality and sexual motivation of their potential mates.
Testosterone Affects The Acoustic Structure Of The Male Call In The Grey Partridge (Perdix Perdix)
FUSANI, Leonida;
1994
Abstract
The effects of testosterone (T) on the acoustic features of the ''rusty-gate'' call of the grey partridge, a non-oscine bird, were studied in 24 males kept in semi-natural conditions. Half of them were implanted subcutaneously with T propionate in Silastic tubes at 10 weeks of age, the remaining were sham operated as controls. After one month implanted males showed significantly higher T levels than controls, while treatment did not affect body size. Individual recordings of calls were analysed and accurate measurements were taken by a digital spectrograph. The duration of calls was significantly greater in T-males than in controls. A similar lengthening has been described in nature in spring, when plasma levels of androgens rise. The frequencies of the most intense portion of the call ranged more widely and had a lower minimum in T-males than in controls, suggesting an hormonal control on call system at the peripheral/central level. In conclusion T affects specific temporal and frequency features of the male calls. The relationship between T and call structure could enable females to assess quality and sexual motivation of their potential mates.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
