Wax skin
Wax skin is the name given to an unfeathered area in the nasal region of birds above the beak (also: nasal skin). It got its name because of its waxy appearance. The nostrils lie in the front area of the wax skin .
In ornithology, the appearance of the wax skin is a criterion for distinguishing closely related species , and in sex-dimorphic species such as budgies , also the sexes.
literature
- Peter R. Stettenheim: The Integumentary Morphology of Modern Birds — An Overview . In: Integrative and Comparative Biology . 40, No. 4, August, pp. 461-477. doi : 10.1093 / icb / 40.4.461 .