| 要旨トップ | 目次 | | 日本生態学会第73回全国大会 (2026年3月、京都) 講演要旨 ESJ73 Abstract

一般講演（ポスター発表） P1-503 （Poster presentation）

#### Linking Ecological Factors to Bare Part Coloration in Estrildid Finches【A】【E】

*Victor Manuel BAQUERA, Masayo SOMA（Hokkaido University）

Ecogeographical gradients in bird coloration have been observed across taxa which have led to several rules linking coloration and habitat structure. For instance, the simple version of Gloger’s rule states that animals inhabiting warmer and more humid environments will be darker due to increased melanin deposition. It has also been suggested that a latitudinal gradient in coloration exists with species closer to the equator having greater color diversity due to increased sexual selection pressures. Most research on bird coloration has focused solely on plumage leaving bare parts heavily understudied despite their importance in mate attraction and survival. Here we attempt to disentangle how bare part coloration relates to these observed global distributions. Using the Estrildidae family we test whether beak and leg coloration conform to Gloger’s rule or exhibit latitudinal patterns consistent with sexual signaling. Utilizing species occurrence data obtained from international biodiversity databases in addition to climatic data; we conducted a phylogenetic regression analysis across phylogenetic trees to evaluate how environmental factors correlate with bare part coloration for both native and non-native occurrences. Phylogenetic models revealed that native occurrences’ beak coloration aligned closely with the predictions of Gloger’s rule with darker coloration being positively correlated with humidity. In non-native occurrences we observed a pattern directly contradicting Gloger’s rule with darker coloration negatively correlating with precipitation. Our findings are some of the first to apply these ecogeographical rules to bare part coloration while finding that bare part coloration is more complex than previously thought.

日本生態学会