Cavernous rock strata contain abundant additional voids of varying sizes, which may not be passable by humans. These voids are interconnected by a vast system of cracks and solution channels. The smaller capillary-sized spaces are less important biologically because their small size limits the amount of food resources they can hold and transport. Voids larger than about 5 cm can transport large volumes of food as well as serve as habitat for animals. In terms of surface area and extent, these intermediate-size voids are the principal habitat for specialized cave animals. Many aspects of their life history may occur only in these spaces. Some cave species (such as the earwig, Anisolabis howarthi (Figure 2), and sheet web spiders, Linyphiidae, in Hawaiian lava tubes) prefer to live in crevices and are only rarely found in caves. In addition, cave-adapted animals have been found living far from caves in cobble deposits beneath rivers, fractured rock strata, and buried lava clinker in Japan, Hawai'i, Canary Islands, Australia, and Europe. These discoveries corroborate the view that cave adaptation and the development of cave ecosystems can occur wherever there is suitable underground habitat.
Because these smaller voids are isolated from airflow from the surface, the environment resembles the stagnant air zones of caves. Caves serve as entry points and windows in which to observe the fauna living within the voids
in the cavernous rock strata. The view is imperfect because the environment is so foreign to human experience.
Was this article helpful?