A comparative SEM study of the guard hair architecture in subterranean moles (Talpidae, Soricomorpha), golden moles (Chrysochloridae, Afrosoricidae), and silvery mole-rats (Bathyergidae, Rodentia)

Abstract

The architecture (external and internal structure) of guard hairs was studied using SEM and comparative morphological approach in representatives of three orders of subterranean mammals: Eurasian moles Talpa altaica and Mogera robusta; American moles Scapanus townsendii and Urotrichus talpoides (Talpidae, Soricomorpha); African golden moles (Chrysochloridae, Afrosoricidae) Amblysomus hottentotus, Calcochloris obtusirostris, Carpitalpa arendsi, Chrysochloris asiatica, Chrysospalax villosus, Cryptochloris wintoni, and Eremitalpa granti; and an African rodent, the subterranean mole-rat Heliophobius argenteocinereus (Bathyergidae, Rodentia). We have shown that representatives of phylogenetically distant taxa of high rank (at the order level) have examples of convergent evolution of pelage in the adaptation to a digging tunneling life-style. At the same time, comparison of the entire set of parameters of the studied structures reveals species-specific features of the hair structure, which possibly reflect certain differences in living conditions, including various substrate types. Hairs from different parts of the body exhibit no topographic differences in structure, which is explained by a relative homogeneity of moles’ habitat. Cuticular ornamentation may prove useful in species identification of these mammals.