Compared to acoustically unspecialized mammals (soricids and murids), the middle ear of subterranean insectivores and rodents (twelve species of six families examined) was clearly distinguished and characterized by many common features: rather round and relatively larger eardrum without a pars flaccida; reduced gonial; loose or no connection between the malleus and the tympanic bone; reduced and straightened transversal part of the malleus; enlarged incus; increased and rather flat incudo-mallear joint; rather parallel position of the mallear manubrium and incudal crus longum in some species (and their fusion in bathyergids); reduced or even missing middle ear muscles. Convergent occurrence of these structural features in taxa of different origin and their generally derived character suggest that they cannot be categorized as degenerative. The form of the stapes can be considered as a non-adaptive trait; it was taxon specific yet remarkably polymorphous in some species and exhibited no convergent features among subterranean mammals. Structural retrogression resulting in a columella-like stapes was observed in some species lacking the stapedial artery. The stapedial base was relatively larger than in unspecialized mammals. The subterranean mammals did not exhibit conspicuously enlarged eardrums as would be required for sensitive tuning to low frequencies. It is, however, argued that while selective pressures in the subterranean ecotope promoted hearing of low frequencies, hearing sensitivity did not have to be enhanced.

An effective live-trap was designed for Cryptomys hottentotus (Bathyergidae) and Amblysomus hottentotus (Chrysochloridae). Factors involved in the design and adaptability of this trap for use in various field conditions and live capture of other fossorial mammals are discussed.

The mammalian tail, present in all mammalian species, has evolved as a surprisingly multi‐purpose and important appendage. The major conservative feature appears to be retention of the tail as a single, unbranched appendage; otherwise, colour, shape, size and mobility vary greatly. Not all of the adaptations discussed are common to all mammalian orders, and no single mammalian order has all the different adaptations occurring in it. These diverse functions may be useful in interpreting behavioural observations, and function as potential guideposts for further investigation.

Eremitalpa granti namibensis is a small, blind insectivorous mole endemic to the sand dunes of the Namib Desert. Unlike most other subterranean mammals, E. g. namibensis lacks a permanent burrow system and forages for its prey on the dune surface at night. This study examines the natural dietary habits and foraging behaviour of E. g. namibensis in relation to resource abundance and distribution in the Namib dunes. Stomach content analysis revealed termites as the major dietary item with other invertebrates being of only minor importance. Biomass of potential prey items was found to be low and food resources patchily distributed. It is suggested that desert moles opportunistically exploit a sedentary prey resource which occurs in patches of high concentrations, hence avoiding the energetic costs implicit in pursuing more mobile prey. Qualitative and quantitative descriptions of nocturnal foraging paths were undertaken so that searching behaviour could be related to the variation and distribution of food items. It is concluded that movement patterns of moles are effective in encountering localized areas of high prey concentrations and in minimizing energy expenditure in an energy‐sparse environment.

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