agents:  the servants of rulers, conquerors and governments. The first agents relayed the orders of an army to a conquered people.

agricultural revolution:  used to be considered to be the invention of agriculture, and a prime factor in the development of "civilization." Now it refers to the adoption of grain farming and the development of slavery.

boid:  a virtual 'bird' that behaves according to the rules of the computer program 'boids.'

boiled frog syndrome:  refers to the way people can ignore small changes, even though they can add up to a big problem. The expression refers to the physiological phenomenon that if you drop a frog into a pot of hot water it will try to get out, but if you drop the same frog into a pan of lukewarm water and then heat the pan gently, the frog will not appear to notice while it is cooked alive.

bottleneck:  in evolution, a condition or event that kills a significant percentage of a population. The survivors of a bottleneck become the ancestors of future generations, and the genetic characteristics of those who do not survive are deleted from the racial heritage.

bourse:  a stock exchange. The name derives from the name of the Van der Buerse family, of Bruges, in Belgium.

camp:  a private compound of temporary or permanent residences. A camp may be very similar to a village, with the exception that a village has public areas which are open to non-residents. A camp may have common areas, but the camp itself is open only to residents and invited guests.

charismatic leader:  a leader who controls his followers by the force of his/her personality.

church:  either a building or a system or metasystem of people who worship a common god, with common rituals.

clearances:  the mass eviction of tenant farmers in Scotland, between about 1810 and 1850.

composite life form:  an entity that appears to be a single life form, but is in fact made up of two or more symbiotic life forms. Lichen, for example, is a composite life form made up of amoeba and algae.

conventional wisdom:  a collection of things that "everyone knows" to be true. In some cases they are actually true, in others, they are not. At one time "conventional wisdom" in many cultures included the belief that the world was the center of the universe, and that the sun orbits around it.

corporation:  any group of individuals that can operate as a single entity. A colony of ants or bees is a corporation, and so is an army or a troop of girl scouts.

drift, evolutionary:  the general direction of evolution. Modern science does not argue that evolution leads to "higher" forms of life, but rather to forms that are better suited to survive prevailing conditions.

drunkard's walk:  science writer Stephen Jay Gould's explanation of how the evolutionary {ratchet} works. Imagine a narrow road with a high wall on one side and a deep ditch on the other. Now imagine a drunk, reeling down this road on a dark night. He may bump into the wall several times but, sooner or later, he will wind up in the ditch.

emissions controls:  devices added to American cars in the early 1970's, in an attempt to minimize pollution. They changed the nature of emissions but, because they increased fuel consumption, they actually increased both emissions and pollution. Cars sold in many countries are still required to have emissions controls.

enclosures:  in England in the late 17th century, many fields which had been "commons" on which anyone could graze animals were "enclosed," and used for private production.

establishment:  the metasystem that rules a human society. It usually includes priests, leading teachers, soldiers, land-owners and sometimes the most wealthy citizens.

evolution:  a process of gradual change. The most common use of the word relates to changes in populations of living things but the concept also applies to changes in tools and social systems.

extended family:  a group of related people, usually including three or more generations and several couples. Because of inter-marriage every extended family is inter-related with several other extended families.

fig wasp:  a wasp that lays its eggs only in one type of fig, which are pollinated only by fig wasps.

hydrozoan:  a form of sea life which appears to be a single animal, but is in fact a highly integrated colony of similar animals. The individual animals that comprise a hydrozoan are called "zooids."

Janissaries:  slave soldiers of the Ottoman Empire. The army of the Janissaries was established in the late 14th century and lasted about 300 years.

!Kung San:  hunter/gatherers who live in South Africa and Botswana. They are sometimes called "bushmen."

Mamluk:  a slave-soldier in an army formed in 833 AD to serve the Caliph of Baghdad. The army revolted and, for several hundred years, Mamluks were appointed the caliphs of several Arab countries and established dynasties of their own to rule Syria, Egypt and part of India.

manganese methylcyclopentadienyl tricarbonyl:  (MMT) a gasoline additive which is known to cause damage to human nervous systems. It is banned in some American states, but allowed in Canada.

marsupial wolf:  an extinct carnivore that once lived in Australia. It did not survive the arrival of Dingo dogs in Australia but a close relative, the "Tasmanian Tiger," was common in Tasmania until the arrival of white men.

meta-life:  a system which may not be "alive" in the usual sense, but which acts as though it were.

metasystem:  a group of people or of systems with a common interest but no formal bonds.

monocultures:  large areas in which only one plant grows. The term is usually applied to farmers fields in which one crop is planted and tended, and all other plants are excluded.

Muller's Ratchet:  the biological principle that some evolutionary steps can not be undone. Named for American geneticist and Nobel Laureate Hermann Joseph Muller

negative feedback:  a type of sub-system which controls, and stabilizes, a system. In the most familiar example a home thermostat turns a heating system on when a room is cool, and turns it off when the room is warm.

nuclear family:  one man with one or more wives and their young children.

obsidian:  volcanic glass which was used to make stone age tools, and is now used to make some surgeon's scalpels.

positive feedback:  a type of sub-system which tends to de-stabilize a system. The most familiar example is the ear-shattering screech which may be produced by a sound system when a microphone picks up the hiss of the speakers and amplifies it.

Prisoner's Dilemma:  a game, once used in sociology classes to illustrate the value of betrayal. Now known to demonstrate the value of co-operation.

pristine state:  the first stage in the evolution of a clan or tribal organization into a state. States which are not "pristine" are evolved from other states.

propaganda:  persuasion intended to instill a point of view, rather than encourage specific action.

ratchet:  the process by which evolution moves in steps which can not be reversed. See "drunkard's walk."

rationale:  a set of beliefs which shapes an individual's view of the world.

selective breeding:  the practice of allowing animals with selected characteristics to breed, in hopes of maximizing the chosen characteristics

settler effect:  an evolutionary process which begins when one population of plants or animals is isolated from others of its kind and begins to evolve differences.

siphonophorans:  marine life forms which look like jellyfish but are in fact colonies of individual animals called "zooids" The best-known siphonophoran is called the "Portuguese Man-of-war."

slime mold:  a life form which looks and acts like a single animal, but is in fact a colony of amoebas.

stratification:  the development of social/economic classes, or castes, in an egalitarian society.

subliminal:  stimuli which we perceive below the level of consciousness. The term is often used to refer to "hidden" messages within advertisements.

superliminal:  stimuli which are so obvious that we don't notice them. When we watch a sailboat on a fine day we know that the sea and the sky and the sunlight are there, but we are watching the sailboat.

Tit for Tat:  the winning strategy in a world-wide tournament of {Prisoner's Dilemma} games, played by computers.

trans-national corporations:  corporations in which ownership, control and operations are spread so widely that they can not be controlled by any single national government.

tuber gardens:  the first form of "farming." The first tuber gardens apparently grew yams, in Central Africa, several thousand years before the "agricultural revolution."

Venus flytrap:  a carnivorous flower that traps and absorbs flies and other insects.

village:  physically similar to a camp, but open to visitors and new residents.

Virella mite:  an Asian mite, recently imported to North America, which attacks honey bees.

wrasse:  a type of tropical reef fish that cleans the teeth of other reef fish

youth culture:  the metasystem of modern youth and the systems and metasystems that dominate and control them.

yucca moth:  a moth that hatches from eggs laid in yucca plants, which are pollinated only by yucca moths

zooid:  one of the individual animals which, together, comprise a hydrozoan.