MIXED-SEX PHENOTYPES IN THE ANDEAN CONDOR: NATURALLY OCCURRING ABNORMALITY OR ENVIRONMENTALLY INDUCED DISORDER?

ALARCÓN, P. A. E.; IGNAZI, G. O.

JOURNAL OF RAPTOR RESEARCH

RAPTOR RESEARCH FOUNDATION INC

Lugar: Lawrence, Kansas; Año: 2021

0892-1016

While most New and Old World vultures are sexually-monomorphic bird species, the Andean condor (Vultur gryphus) is well known for showing conspicuous phenotypic differences between sexes. Here we first report the appearance of phenotypes that combine female- and male-typical characters and go on to discuss the most likely underlying causes. Owing to Andean condor populations are increasingly exposed to endocrine-disrupting contaminants (e.g. pesticides and lead), our strongest hypothesis is that contaminant-driven hormonal imbalances are at the root of the documented observations. We hope our report will lead both naturalists and scientists to keep a close eye on the occurrence of these disorders and inspire specific studies to better understand its origin.