Studies on the syrinx of gallus domesticus

Voice Breaking in Males Results in Sexual Dimorphism of Green Woodhoopoe Calls

“…Rosenfield & Bielefeldt, 1991;Farquhar, 1993), usually explained by the female being the larger sex. Sex differences in body size are likely to be reflected in the size of the soundproducing organ (Myers, 1917;Ballintijn & ten Cate, 1997a), with a larger syrinx resulting in a lower frequency of sound produced (between species: Ryan & Brenowitz, 1985;within species: Würdinger, 1970), although the precise linkage between sound structure and syringeal morphology remains unclear. Given that adult male green woodhoopoes are 5-8% larger than adult females in most linear measures (Radford & du Plessis, 2003), the intersexual difference in body size might be expected to explain the lower frequency of adult male calls.…”

Dimorfismo sexual da traquéia e siringe de periquito (Touist sp.)

“…A siringe é constituída por quatro componentes cartilaginosos: as cartilagens craniais, as cartilagens intermediárias, as cartilagens caudais e o pessulo (Myers, 1917). No pato ela é assimétrica e forma a bolha timpaniforme, uma grande caixa dilatada localizada no lado esquerdo, estrutura ausente nas fêmeas (King, 1986).…”

Mineralization in the syrinx and caudal tracheal rings in the ostrich

“…He also reported that the cranial component of the trachea was lightly stained completely. Likewise, Gross (1964) and Myers (1917) showed ossification in the tympanum and in the first ring of the bronchial cartilages of the syrinx in adult chicken, respectively. On the other hand, none of the mineralized tracheal rings in this study displayed complete staining.…”