Melanism in a Wild Sifaka Population: Darker Where Cold and Fragmented

Pigmentation is one of the most striking examples diversity in natural world. Specifically, primate pelage (hair/fur) pigmentation provides a substrate for selection, and tied to functions such as crypsis, signaling, thermoregulation. However, our hypotheses on forces responsible are based solely macro-evolutionary studies. Here, we test how distinct around climate, age, sex might be influencing color variation wild population. We characterize pattern within population diademed sifakas (Propithecus diadema) exhibiting coloration (melanic tri-colored). Our approach jointly assesses climate across region. score using semi-quantitative methodology (n = 87 individuals). then if associated with climatic or demographic factors (i.e., sex–class, age–class) Tsinjoarivo forest, Madagascar. find darker bodies greater facial complexity colder more fragmented forests. conclude that three explanations may explain phenotypic pattern: isolation by distance, an environmental gradient, local adaptation. Although it difficult reach causal conclusion without genetic data, each scenario signals need enhanced conservation forest. More studies populations will needed contextualize this exceptional typical. argue also foretell either adaptation maladaptation via mismatch).