The uropygial gland of the Eared Dove and the evolutionary history of this organ within Columbiformes (Aves)

CHIALE MC; CARRIL J, ; MONTALTI D; BARBEITO CG

JOURNAL FUR ORNITHOLOGIE

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2019 vol. 160 p. 1171 - 1181

0021-8375

The uropygial gland (UG) is an exclusive holocrine organ unique of Aves. Althoughseveral studies have been performed on the UG of different species, the knowledgeabout the UG in Columbiformes is scarce. In order to fill this gap, we analyse in detailthe external morphology and the histological and histochemical features of the UG ofthe Eared Dove (Zenaida auriculata) in a comparative context. The UG of the EaredDove is characterized by the presence of a pear-like shape composed of two lobes, aconical and naked papilla, tubule-alveolar adenomers, a large primary storagechamber (feature also present in other terrestrial species), and the presence ofreticular and elastic fibers in the capsule and connective tissue surrounding theadenomers. Histochemistry showed positive reaction to PAS, Alcian Blue 2.5 andseveral lectins, evidencing the presence of diverse glycoconjugates in this organ.Since the UG may be independently present or absent within Columbiformes, we alsoused character mapping over a molecular phylogeny to infer the character states of theUG at ancestral nodes in order to understand its evolutionary history. The analysisshow that presence of the UG was the ancestral state for Columbiformes and that itslost evolved more than once independently.