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Dominance-related seasonal song production is unrelated to circulating testosterone in a subtropical songbird.

York JE, Radford AN, de Vries B, Groothuis TG, Young AJ - Gen. Comp. Endocrinol. (2016)

Bottom Line: However, while dominant males were more likely to sing and sang for longer than subordinate males, within-group paired comparisons revealed no dominance-related differences in circulating T.Moreover, comparisons both among and within individual dominant males revealed that song duration, syllable rate and proportion of time spent singing were all unrelated to circulating T.More widely, our results are in line with the view that male song production is not exclusively regulated by gonadally synthesized steroids.

View Article: PubMed Central - PubMed

Affiliation: Centre for Life and Environmental Sciences, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK; School of Biological Sciences, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK. Electronic address: jenny.e.york@gmail.com.

No MeSH data available.


Related in: MedlinePlus

(a) Song production by dominant and subordinate males across the breeding season (commencing 1st October 2010) showing the probability that one or more subordinate males (solid grey line), and the probability that the dominant male (solid black line), in a group sang on a given morning, dashed lines indicate 95% CIs (using GLMM predictions, based on data from 216 dawn observation sessions at 24 groups containing at least one subordinate male); (b) plasma testosterone concentration (square root-transformed) across the breeding season for subordinate (open circles, n = 61 samples from n = 37 males) and dominant males (black circles, n = 72 samples from n = 40 males; solid black line represents predictions from LMM, dashed lines represent 95% CIs).
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f0015: (a) Song production by dominant and subordinate males across the breeding season (commencing 1st October 2010) showing the probability that one or more subordinate males (solid grey line), and the probability that the dominant male (solid black line), in a group sang on a given morning, dashed lines indicate 95% CIs (using GLMM predictions, based on data from 216 dawn observation sessions at 24 groups containing at least one subordinate male); (b) plasma testosterone concentration (square root-transformed) across the breeding season for subordinate (open circles, n = 61 samples from n = 37 males) and dominant males (black circles, n = 72 samples from n = 40 males; solid black line represents predictions from LMM, dashed lines represent 95% CIs).

Mentions: The probability of song production was significantly predicted by an interaction between dominance status and season day2 (GLMM: χ21 = 50.83, n = 432 observations from 216 sessions at 24 groups, p < 0.001; Fig. 3a). The probability of song production peaked for both classes halfway through the population-level breeding season, but dominant males were differentially more likely than subordinates to sing towards the start and end of the breeding season, indicating that the magnitude of the effect of dominance status on the probability of song production depended on the time in the season (Fig. 3a). This result held when data collected during within-group egg laying were excluded (χ21 = 11.46, n = 400 observations from 200 sessions at 24 groups, p < 0.001).


Dominance-related seasonal song production is unrelated to circulating testosterone in a subtropical songbird.

York JE, Radford AN, de Vries B, Groothuis TG, Young AJ - Gen. Comp. Endocrinol. (2016)

(a) Song production by dominant and subordinate males across the breeding season (commencing 1st October 2010) showing the probability that one or more subordinate males (solid grey line), and the probability that the dominant male (solid black line), in a group sang on a given morning, dashed lines indicate 95% CIs (using GLMM predictions, based on data from 216 dawn observation sessions at 24 groups containing at least one subordinate male); (b) plasma testosterone concentration (square root-transformed) across the breeding season for subordinate (open circles, n = 61 samples from n = 37 males) and dominant males (black circles, n = 72 samples from n = 40 males; solid black line represents predictions from LMM, dashed lines represent 95% CIs).
© Copyright Policy - CC BY
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4920672&req=5

f0015: (a) Song production by dominant and subordinate males across the breeding season (commencing 1st October 2010) showing the probability that one or more subordinate males (solid grey line), and the probability that the dominant male (solid black line), in a group sang on a given morning, dashed lines indicate 95% CIs (using GLMM predictions, based on data from 216 dawn observation sessions at 24 groups containing at least one subordinate male); (b) plasma testosterone concentration (square root-transformed) across the breeding season for subordinate (open circles, n = 61 samples from n = 37 males) and dominant males (black circles, n = 72 samples from n = 40 males; solid black line represents predictions from LMM, dashed lines represent 95% CIs).
Mentions: The probability of song production was significantly predicted by an interaction between dominance status and season day2 (GLMM: χ21 = 50.83, n = 432 observations from 216 sessions at 24 groups, p < 0.001; Fig. 3a). The probability of song production peaked for both classes halfway through the population-level breeding season, but dominant males were differentially more likely than subordinates to sing towards the start and end of the breeding season, indicating that the magnitude of the effect of dominance status on the probability of song production depended on the time in the season (Fig. 3a). This result held when data collected during within-group egg laying were excluded (χ21 = 11.46, n = 400 observations from 200 sessions at 24 groups, p < 0.001).

Bottom Line: However, while dominant males were more likely to sing and sang for longer than subordinate males, within-group paired comparisons revealed no dominance-related differences in circulating T.Moreover, comparisons both among and within individual dominant males revealed that song duration, syllable rate and proportion of time spent singing were all unrelated to circulating T.More widely, our results are in line with the view that male song production is not exclusively regulated by gonadally synthesized steroids.

View Article: PubMed Central - PubMed

Affiliation: Centre for Life and Environmental Sciences, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK; School of Biological Sciences, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK. Electronic address: jenny.e.york@gmail.com.

No MeSH data available.


Related in: MedlinePlus