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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

Across-male correlation (n = 28 dominant males; 37 matched song and plasma samples) of T and (a) song performance duration, (b) song rate (syllables/min), and (c) proportion of time spent singing; within-male difference (n = 9 dominant males) from the lower to the higher circulating T session in (d) dawn song performance duration; (e) song rate (syllables/min); and (f) proportion of time spent singing; within-male change (n = 9 dominant males) in T between the two matched sample sessions and within-male change in (g) dawn song performance duration (min); (h) song rate (syllables/min); and (i) proportion of time spent singing.
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f0025: Across-male correlation (n = 28 dominant males; 37 matched song and plasma samples) of T and (a) song performance duration, (b) song rate (syllables/min), and (c) proportion of time spent singing; within-male difference (n = 9 dominant males) from the lower to the higher circulating T session in (d) dawn song performance duration; (e) song rate (syllables/min); and (f) proportion of time spent singing; within-male change (n = 9 dominant males) in T between the two matched sample sessions and within-male change in (g) dawn song performance duration (min); (h) song rate (syllables/min); and (i) proportion of time spent singing.

Mentions: Across all sampled dominant males (n = 37 matched T and song measures from the same day from n = 28 dominant males), dawn song performance duration was not significantly predicted by their matched circulating T concentration (LMM: χ21 = 0.04, p = 0.84; Fig. 5a) when controlling for the significant effect of season day (χ21 = 11.10, p < 0.001). Interaction terms between season day2 and T (χ21 = 0.06, p = 0.80) and season day and T (χ21 = 0.01, p = 0.91) were not significant, and neither was season day2 (χ21 = 2.30, p = 0.13), as would be expected given that the matched sampling of song and T was carried out only during the peak breeding months.


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)

Across-male correlation (n = 28 dominant males; 37 matched song and plasma samples) of T and (a) song performance duration, (b) song rate (syllables/min), and (c) proportion of time spent singing; within-male difference (n = 9 dominant males) from the lower to the higher circulating T session in (d) dawn song performance duration; (e) song rate (syllables/min); and (f) proportion of time spent singing; within-male change (n = 9 dominant males) in T between the two matched sample sessions and within-male change in (g) dawn song performance duration (min); (h) song rate (syllables/min); and (i) proportion of time spent singing.
© Copyright Policy - CC BY
Related In: Results  -  Collection

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

f0025: Across-male correlation (n = 28 dominant males; 37 matched song and plasma samples) of T and (a) song performance duration, (b) song rate (syllables/min), and (c) proportion of time spent singing; within-male difference (n = 9 dominant males) from the lower to the higher circulating T session in (d) dawn song performance duration; (e) song rate (syllables/min); and (f) proportion of time spent singing; within-male change (n = 9 dominant males) in T between the two matched sample sessions and within-male change in (g) dawn song performance duration (min); (h) song rate (syllables/min); and (i) proportion of time spent singing.
Mentions: Across all sampled dominant males (n = 37 matched T and song measures from the same day from n = 28 dominant males), dawn song performance duration was not significantly predicted by their matched circulating T concentration (LMM: χ21 = 0.04, p = 0.84; Fig. 5a) when controlling for the significant effect of season day (χ21 = 11.10, p < 0.001). Interaction terms between season day2 and T (χ21 = 0.06, p = 0.80) and season day and T (χ21 = 0.01, p = 0.91) were not significant, and neither was season day2 (χ21 = 2.30, p = 0.13), as would be expected given that the matched sampling of song and T was carried out only during the peak breeding months.

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