ELLIOTT ET AL.: THE CAVE FAUNA OF CALIFORNIA 
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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 rema ins of plants and animals. 
Parietal fauna: Pertaining to the inhabitants on the walls of the entrance and twilight zones of a cave. 
Paleozoic Era: An interval of geological time from about 541 to 252 Ma (million years ago.) 
Permian Period: A geologic period and system which extends from 298.9 to 252.17 Ma (million years ago). 
It is the last period of the Paleozoic Era, following the Carboniferous Period and preceding the Triassic 
Period of the Mesozoic Period. 
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. 
Phreatobite: An inhabitant of groundwater, often exhibiting troglomorphy, but usually not found in caves. 
Many blind amphipods and other crustaceans are found in springs, upwellings and bottoms of streams, 
the hyporheos below stream beds, gravels, wells, and deep lakes. 
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 most or 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 Epoch: Pertaining to the epoch in the earth’s history from 2,588,000 to 11,700 years ago, when 
the last major glaciation ended. The epoch includes at least four major retreats and advances of conti¬ 
nental glaciers. See also Holocene. 
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 net¬ 
works 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 manu¬ 
facture the food on which all other living things ultimately depend. They are available in the cave com¬ 
munity only in the twilight zone, or as debris that falls or washes in. A few types of bacteria also manu¬ 
facture food from nonliving substances and therefore serve as producers in some cave communities. See 
also Consumer. 
Psychrometer: An instrument used for measuring atmospheric saturation or 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 ther¬ 
mometers 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 reorganization of its tissues in the process of becoming an adult. See also Metamorphosis. 
Pseudokarst: A cave area that resembles karst but that is not formed by the dissolution of soluble rocks. 
Examples are lava tubes and related features, talus caves, soil-pipe caves, tectonic caves, sea caves, and 
others. 
Quaternary Period: Relating to the most recent period in the Cenozoic era, following the Tertiary period and 
comprising the Pleistocene and Holocene epochs (and thus including the present). 
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. 
Sea cave: Also known as a littoral cave, a type of cave formed primarily by the erosive wave action of the 
sea. 
