Identification of mammals based on hair microstructure: Methodological adaptations and new morphological patterns

Abstract

The characterization of patterns of hair microstructure is an important instrument for studying the diet and ecology of mammals, representing an accessible method for identifying predators and their prey. The present study aimed to: (1) describe methodological adaptations developed to optimize traditional guard hair analysis protocols; (2) propose adjustments in the classification of morphological patterns of medulla and cuticle; and (3) establish the microstructural pattern of Brazilian mammals’ hair to assist in the identification of prey and predators in studies based on fecal samples. Hairs from 53 mammal species, including small (n = 16), medium (n = 28) and large size (n = 9), distributed in 24 families and nine orders were analyzed. The orders with the most species analyzed were Carnivora (n = 14), Rodentia (n = 13) and Didelphimorphia (n = 8), while the most representative families were Didelphidae (n = 8), Cricetidae (n = 7) and Felidae (n = 6). Among the species, 13 (24.5% of the total) did not have the microstructural patterns described in studies developed previously in Brazilian territory: Alouatta guariba, Blarinomys breviceps, Bradypus torquatus, Callicebus personatus, Callithrix geoffroyi, Dasyprocta leporina, Hylaeamys seuanezi, Potos flavus, Priodontes maximus, Rhipidomys mastacalis, Sapajus robustus, Sylvilagus minensis and Tayassu pecari. More descriptive nomenclatures were proposed regarding the observed patterns and new patterns were described for species evaluated in previous studies. Our results contribute to the diagnosis of species to be more accurate, contributing to the development of future studies.