Although at least some of the underground dwellers have been known for many years, their biology has remained unstudied. This may be explained by the cryptic way of life of subterranean animals, and technical problems related with keeping, breeding, and observing them.
The fact is, scientists were always more fascinated by animals coping with complicated environments and solving seemingly difficult and complex problems than by those encountered by mammals underground (sensitive vision versus blindness; echolocation in a highfrequency range versus hearing in a human auditory range; navigating across hundreds or thousands of miles versus maze orientation across tens of feet; thermoregulation in cold environments versus life in a thermally buffered burrow, etc.).
Interestingly, although many preserved specimens of moles (i.e., insectivorous subterranean mammals) and mole-
It may be of interest to examine the literature dealing with ecology, evolution, morphological, physiological, and behavioral adaptations of subterranean mammals. Although there are some relevant scientific papers published as early as at the beginning of the nineteenth century, the real exponential growth of the research and publishing activity referring to subterranean mammals started in the 1940s. Since then, the number of publications has doubled about every 10 years. Thus, 56% of about 1,300 scientific papers addressing at least partly adaptations of subterranean mammals and published to date appeared after 1990, a further 25% are dated 1981 to 1990, and another 11% appeared between 1971 and 1980.
The interest in adaptations of subterranean mammals has been triggered particularly by two seminal papers on the blind mole-