Glossary of Biospeleology




This glossary is taken mostly from "The Life of the Cave," by Charles E. Mohr and Thomas L. Poulson, 1966, McGraw-Hill, with the kind permission of Thomas L. Poulson.  Some additions are by William R. Elliott.  New words and definitions will be added with the help of the readers (I have a large word list that needs to be defined.)




Adaptation: An inherited structural, functional, or behavioral characteristic that improves an organism's chances for survival in a particular habitat. See also Mutation.


Antenna (plural antennae): A feeler; an appendage, sensory in function, that occurs in pairs on the heads of crustaceans, insects, and certain other animals.


Appendage: An arm or other limb that branches from an animal's body.


Aquatic: Living in water. Aquatic cave animals include amphipods, isopods, crayfish, planarians, fish, and blind salamanders. See also Terrestrial.


Arthropods: Animals with jointed legs and bard external skeletons (exoskeletons). The group includes insects, crustaceans, spiders, millipedes, and several other types of animals commonly found in caves.


Bacteria: Simple, colorless one-cell plants, most of which are unable to manufacture their own food using sunlight Bacteria are possibly important in caves as synthesizers of food materials from minerals. They are also important as decomposers.


Barbels: Fleshy threadlike sensory structures hanging like whiskers near the mouths of certain fish, such as catfish.


Bathybenthic: Of the bottom of the truly deep areas of the sea, where the "rain" of organic material produces a deposit of food.


Bathypelagic: Of the deep sea. Refers to the depths between roughly 3000 feet below the surface and the bottom of the sea. No food accumulates in these waters.


Biological clock: An inherited time-measuring process within a living thing, which governs its responses to certain external events.


Biomass: The total weight of living matter, whether in an entire community, at a particular trophic level, or of a particular kind of organism in the community. Thus we may refer to the biomass of a pond community, of herbivores in the pond, or of copepods in the pond.


Biospeleology: The scientific study of cave animal life, or the biology of caves, karst, and groundwater. A biologist who specializes in this study is called a biospeleologist


Breakdown: A heap of rock filling all or part of a cave passage after the collapse of part of the walls or ceiling. The term usually refers only to large accumulations of rock.


Carbide lamp: A type of lamp used by miners and cave explorers. It maintains a flame by burning acetylene, a gas produced when water drips on a supply of calcium carbide pellets.


Carnivore: An animal that lives by eating the flesh of other animals. See also Herbivore; Insectivore; Omnivore.


Cave: Any natural cavity or series of cavities beneath the surface of the earth. Such cavities are usually classed as caves only if they are large enough to permit entrance by humans. The term is generally synonymous with cavern and is commonly applied also to wind- or water-eroded rock cavities.


Cave deposit: An accumulation of material other than speleothems, such as charcoal, fossils, clay, silt, gravel, and other flood-borne debris.


Caver: A person who explores caves as a hobby or for recreation. See also Speleologist and Spelunker.


Cave system: All the cavities and underground passages in a given area, which are now or at one time were interconnected.


Chlorophyll: A group of pigments producing the green color of plants; essential to photosynthesis.


Climate: The average weather conditions of an area, including temperature, rainfall, humidity, wind, and hours of sunlight, based on records kept for many years.


Column: A pillarlike speleothem resulting from the union of a stalactite and a stalagmite into a single formation.


Community: All the plants and animals that live in a particular habitat and are bound together by food chains and other interrelations.


Competition: The struggle between individuals or groups of living things for common necessities, such as food or living space.


Conservation: The use of natural resources in a way that assures their continuing availability to future generations; the wise use of natural resources.

Constant-temperature zone: The area of a cave where air temperature is

unchanging throughout the year and approximates the average annual temperature aboveground. See also Zonation.


Consumer: Any living thing that is unable to manufacture food from nonliving substances, but depends instead on the energy stored in other living things. See also Carnivore; Decomposers; Food chain; Herbivore; Omnivore; Producers.


Crustaceans: The large class of animals that includes lobsters, crayfish, amphipods, isopods, and many similar forms. Crustaceans typically live in water and have many jointed appendages, segmented bodies, and hard exoskeletons.


Cupula (plural cupulae): A jellylike rod projecting into the water from a neuromast, part of a fish’s or amphibian’s lateral line system. Vibrations in the water cause the cupula to move, thus setting off nervous impulses that enable the animal to detect nearby movements in the water.


Decomposers: Living things, chiefly bacteria and fungi, that live by extracting energy from the decaying tissues of dead plants and animals. In the process, they also release simple chemical compounds stored in the dead bodies and make them available once again for use by green plants.


Domepit: A large vertical underground shaft where water flowing down to the water table at a lower level has dissolved a cylindrical cavity in the rock.


Drapery: A thin curtainlike speleothem that forms where water trickles down an inclined surface.


Ecology: The scientific study of the relationships of living things to one another and to their environment. A scientist who studies these relationships is an ecologist.


Embryo: A developing individual before its birth or hatching.


Environment: All the external conditions surrounding a living thing.


Epikarst: The upper zone of a karst area that extends downward as sinkholes, fractures, fissures, and other surface karst features to where the natural porosity of the bedrock is located. Epikarst can range from almost nonexistant to tens of meters deep.


Evolution: The process of natural consecutive modification in the inherited makeup of living things; the process. by which mod-ern plants and animals have arisen from forms that lived in the past. See also Mutation.


Exoskeleton: An external skeleton. The hard body covering or shell of most invertebrate animals, including insects, crayfish, and mil-lipedes.


Flowstone: Any mineral deposit that forms on the walls or floor of a cave as a result of water flowing over the surface; often called travertine.


Food chain: A series of plants and animals linked by their food relationships; the passage of energy and materials from producer through a succession of consumers. Green plants, plant-eating insects, and an insect-eating bat would form a simple food chain. See also Food web.


Food pyramid: The normally diminishing number of individuals and amount of organic material produced at each successive level along a food chain. The declining productivity at each level results from the con-stant loss of energy in metabolism as the energy passes along the chain. See also Trophic level


Food web: An interlocking system of food chains. Since few animals rely on a single food source and since no food source is consumed exclusively by a single species of animal, the separate food chains in any natural community interlock and form a web.


Formation: A term commonly used for spe-leothem.


Fossil: Any remains or traces of animals or plants that lived in the prehistoric past, whether bone, cast, track, imprint, pollen, or any other evidence of their existence.


Geological map: A map that shows the kinds of rock lying beneath the soil or reaching the surface in a given area. A topographic map shows the contour or elevation lines, and surface features such as watercourses.


Geology: The scientific study of the earth and the rocks that form it. A

scientist who specializes in this study is a geologist.


Guano: Excrement, as of bats, crickets, or sea birds. In certain bat caves and on islands colonized by sea birds, guano sometimes accumulates in such vast quantities that it is mined commercially for fertilizer.


Gypsum: Hydrated calcium sulphate, a mineral often appearing as outward-curving petal-like "flowers." The rock, softer and more soluble than limestone, is sometimes massive enough to permit cave formation.


Habitat: The immediate surroundings (living place) of a plant or animal; everything necessary to life in a particular location except the organism itself.


Helictite: A thin, twisting speleothem projecting at an angle other than the vertical.


Herbivore: An animal that eats plants, thus making the energy stored in plants available to carnivores. See also Carnivore; Insectivore; Omnivore.


Hibernation: A prolonged dormancy or sleeplike state in which animal body processes such as heartbeat and breathing slow down drastically and the animal neither eats nor drinks. Nearly all cold-blooded animals and a few warm-blooded animals hibernate during the winter in cold climates. Extremely large aggregations of bats, crickets, and spiders hibernate in some caves.


Humidity, relative: The ratio, expressed as a percentage, of the amount of water vapor actually present in air of a given temperature. as compared with the greatest possible amount of water vapor that could be present in air at that temperature. Calculation of relative humidity can be done from tables, special slide rules or calculators, graphs, or complex equations. See also Hygrometer and Psychrometer.


Hygrometer: An instrument that reads the humidity in the air directly; some are based on a hair's ability to shrink or expand with humidity, or on certain electronic chips. Generally, a psychrometer is more accurate at higher humidities (above 95%). See also Psychrometer.


Infrared light: Light not visible to the human eye, with wavelengths longer than those of visible red light and shorter than those of radio waves.


Insectivore: An animal that feeds on insects. Almost all species of North American bats are insectivores. See also Carnivore; Herbivore; Omnivore.


Invertebrate: An animal, such as a planarian, snail, or crayfish, without a backbone. See also Vertebrate.


Karst: The typical surface terrain of a limestone region, characterized by an abundance of sinkholes, disappearing streams, exposed rock outcrops or ledges, and underground caverns. Named for a noted limestone area of northwestern Yugoslavia. See also Epikarst.


Larva (plural larvae): An active immature stage in an animal’s life history when its form usually differs from the adult form, such as the grub stage in the development of a beetle or the tadpole stage in the life history of a frog. See also Metamorphosis; Pupa.


Lateral line system: A series of sensory organs, usually appearing in a line or series of lines on the sides and heads of fishes and larval amphibians. The system enables the animal to sense vibrations in the water. See also Cupula; Neuromast


Limestone: Sedimentary rock composed primarily of calcium carbonate. It usually originates through the accumulation of calcareous (limy) remains of marine animals. Because limestone is easily dissolved by carbon dioxide in water, caves are more common in limestone than in any other type of rock. limestone dissolves fastest where the carbon dioxide content is highest at the surface of the water table.


Mammals: The class of animals that includes bats, mice, man, and many others. They typically have a body covering of hair and give birth to living young, which are nursed on milk from the mother's breast.


Marine relict: An animal whose presently extinct ancestors lived in salt water but became adapted to life in fresh water when an area formerly covered by the sea became dry land.


Metabolic rate: The rate at which a living thing transforms food into energy and body tissue. The higher its metabolic rate, the more food it must consume. Most cave animals live at a reduced metabolic rate.


Metabolism: The sum of the chemical activ-ities taking place in the cells of a living thing; the sum of the processes by which a living thing transforms food into energy and living tissue.


Metamorphosis: A change in the form of a living thing as it matures, especially the drastic transformation from a larva to an adult. See also Pupa.


Microclimate: "Little climate." The environmental conditions, such as temperature; humidity, and air movement, in a very restricted area, such as a sheltered nook in a cave wall.


Microhabitat: A miniature habitat within a larger one; a restricted area where environmental conditions differ from those in the surrounding area. A sheltered nook in a cave wall is an example of a microhabitat within the cave.


Mold: A microscopic form of fungus responsible for much food spoilage and, in caves, for conspicuous tufts quickly covering scats, dead insects and bats, and even wooden structures such as ladders.


Mutation: A sudden change in the genetic material of an organism’s germ cells, resulting in offspring that possess characteristics markedly different from those of either parent. Mutations generally are harmful but occasionally may improve an organism’s chances for survival. See also Adaptation; Evolution.


Neoteny: The condition of retaining larval form and behavior even as a mature individual Certain salamanders in particular are neotenic.


Neuromast: One of the individual sense organs that make up the lateral line systems of fishes and amphibians. See also Cupula.


Omnivore: An animal that habitually eats both plants and animals. See also Carnivore; Herbivore; Insectivore.


Organic: Pertaining to anything that is or ever was alive or produced by a living plant or animal. Organic material brought into the cave from outside is virtually the only source of food for cave dwellers.


Paleontologist: A scientist who studies the life of the past by interpreting fossil remains of plants and animals.


Photosynthesis: The process by which green plants convert carbon dioxide and water into simple sugar. Chlorophyll and sunlight are essential to the series of complex chemical reactions involved in the process.


Pigment: A chemical substance that imparts color to an object by reflecting or transmitting only certain light rays and absorbing all others. For example, a substance that absorbs all but green rays appears green. An object that contains no pigment, on the other hand, appears white because it reflects all light rays and absorbs none. Many troglobites have lost all their pigment


Planarian: A flatworm. A relatively simple wormlike animal with a flattened ribbonlike body, a distinct head end, and a mouth located more or less centrally on the underside of the body.


Pleistocene: Of or pertaining to the most recent period in the earth's history, roughly the past one million years. The period includes at least four major retreats and advances of continental glaciers.


Pollution: The fouling of water or air with sewage, industrial wastes, or other contaminants, making them unfit to support many forms of life. Pollution can be especially serious underground where extensive networks of passages spread contaminating materials for long distances.


Preadapted: Possessing adaptations that would contribute to survival in a habitat other than the immediate one because of similarities in living conditions in the two habitats. Insects that live in leaf litter on the forest floor, for example, may be pre-adapted to cave life.


Predator: An animal that lives by capturing other animals for food. See also Prey.


Prey: A living animal that is captured for food by another animal. See also Predator.


Producers: Green plants, the basic link in any food chain; by means of photosynthesis, green plants manufacture the food on which all other living things ultimately depend. They are available in the cave community only in the twilight zone, or as debris that falls or washes in. A few types of bacteria also manufacture food from nonliving substances and therefore serve as producers in some cave communities. See also Consumer.


Psychrometer: An instrument used for measuring relative humidity. The simplest sling psychrometers consist of two thermometers mounted on a rotating frame. One thermometer’s bulb is kept moist, the other dry. By comparing the “wet bulb” and “dry bulb” readings of the two thermometers after they have been whirled in the air, one can determine the relative humidity. An electric fan is used to ventilate the wet bulb in many psychrometers. See also Hygrometer.

Pupa (plural pupae): The inactive stage in the life history of certain insects during which the larva undergoes a gradual reor-ganization of its tissues in the process of becoming an adult See also Metamorphosis.


Scats: Animal droppings, an important source of food in caves.


Scavenger: An animal that eats the dead remains and wastes of other animals and plants. See also Predator.


Sinkhole: A surface depression in cave country. A sinkhole is produced when the roof of a cave collapses or when limestone rock underlying the soil is slowly dissolved by water.


Soda straw stalactite: A thin-walled tubular stalactite that elongates as minerals are deposited at the tip by water dripping through its hollow interior. All stalactites begin their growth as soda straws.


Sonar: A system for detecting obstacles by emitting sound and intercepting and interpreting echoes that bounce back. It is used by bats and also by oilbirds and some swiftlets when they fly in the darkness of caves.


Species (singular or plural): A group of plants or animals whose members breed naturally only with each other and resemble each other more closely than they resemble members of any similar group.


Speleologist: A person who studies caves in any of their scientific aspects. See also Caver and Spelunker.


Speleothem: A general term for any mineral deposit or formation found in caves, such as stalactites, stalagmites, or gypsum flowers.


Spelunker: A person who explores caves as a hobby or for recreation. In recent years this term has been applied more to the untrained cave visitor. “Cavers rescue spelunkers” is one way that cavers explain the difference. See also Caver and Speleologist.


Stalactite: An iciclelike deposit of calcium carbonate which grows downward from the ceiling of a cave. See also Speleothem; Stalagmite.


Stalagmite: A deposit of calcium carbonate which builds upward from a cave floor as a result of water dripping from above. See also Speleothem, Stalactite.


Terrestrial: Living on land. Terrestrial cave animals include blind beetles, rnillipedes, spiders, and crickets. See also Aquatic.


Troglobite: “Cave dweller.” An animal that lives in caves and nowhere else.


Troglophile: “Cave lover.” An animal that can complete its life cycle in caves but may also do so in suitable habitats outside caves.


Trogloxene: “Cave visitor.” An animal that habitually enters caves but must return periodically to the surface for certain of its living requirements, usually food.


Trophic levels: Feeding levels in a food chain, such as producers, herbivores, and so on. Most food chains include a maximum of four or five trophic levels.


Twilight zone: The area of a cave where light penetrating through the entrance is sufficient to permit human vision. See also Zonation.


Variable-temperature zone: The area of a cave where air temperature fluctuates with the seasons. See also Zonation.


Vertebrate: An animal with a backbone. The group includes fishes, amphibians, reptiles, birds, and mammals. Some amphibians and fishes live permanently in caves. See also Invertebrate.


Water table: The upper level of the under-ground reservoir of water; the level below which the soil and all cracks and channels in the rocks are saturated.


Zonation: The organization of a habitat into a more or less orderly series of distinctive plant and animal associations as a result of variations in environmental conditions. Zones in a cave are the twilight zone, the variable-temperature zone, and the constant-temperature zone.