Table 1.
Neural and muscular specializations found in golden-collared manakins (Manacus vitellinus) likely related to their elaborate courtship displays.
| Tissue/structure | Particularity | Reference |
|---|---|---|
| Brain | ||
| Arcopallium | Sexually dimorphic (M > F); Region-wide expression of androgen receptors | Day et al. (2011) and Fusani et al. (2003a) |
| Hippocampal area | Sexually dimorphic (M > F) | Day et al. (2011) |
| Ventrolateral mesopallium | Sexually dimorphic (F > M) | Day et al. (2011) |
| Spinal cord | ||
| Brachial and lumbosacral enlargements | Widespread expression of androgen- (F> M) and oestrogen receptors | Fuxjager et al. (2012) and Schultz and Schlinger (1999) |
| Motor and sensory neurones innervating limbs | Widespread expression of androgen receptor | Fuxjager et al. (2012) |
| Limb muscles | ||
| Supracoracoideus | Hypertrophied (M > F, M > ZF); Larger fibre size (M > F); Higher proportion of fast-twitch fibres (M > F) | Lowe (1942) and Schultz et al. (2001) |
| Scapulohumeralis dorsalis | Hypertrophied (M > F, M > ZF); Larger fibre size (M > F); Higher proportion of fast-twitch fibres (M > F) | Lowe (1942) and Schultz et al. (2001) |
| Iliotibialis | Hypertrophied (M > F) | Lowe (1942) and Schultz et al. (2001) |