ear ossicles: The three small bones on the inner ear that transmit and transform sound, changing it from an auditory to a nervous signal. The three bones are the malleus (hammer), incus (anvil), and stapes (stirrup).
eclectic: Coming from many sources, as an eclectic diet.
ecofacts: Non-artifactual organic and environmental remains which have cultural relevance, e.g. faunal and floral material as well as soils and sediments.
ecological determinism: A form of explanation in which it is implicit that changes in the environment determine changes in human society.
ecology: The interrelationships between organisms or populations and their environment.
ecotones: A boundary region between ecological zones.
edentulous: Toothless, jaws without any teeth remaining or preserved.
effective population size: The effective number of adults contributing gametes to the next generation.
effector: A small molecule involved in the control of expression of many regulated genes.
elasticity: The property of stone to return to its former state after being depressed by the application of force.
electron probe microanalysis: Used in the analysis of artifact composition, this technique is similar to XRF (X-ray flourescence spectrometry), and is useful for studying small changes in composition within the body of an artifact.
electron spin resonance (ESR): Enables trapped electrons within bone and shell to be measured without the heating that thermoluminescence requires. As with TL, the number of trapped electrons indicates the age of the specimen.
embryo: An organism just after conception; for instance, in humans during the first eight weeks of in-utero development.
eminence: A bony projection.
enamel: The very hard, prismatically structured outer surface of a tooth crown.
enamel wrinkling: Secondaryfolding of the enamel at the occlusal surface of a tooth.
encephalization: The evolutionary trend in which there is a relative increase in brain size beyond that expected from body size.
endinion: The internal occipital protuberance, or internal inion, where the transverse sulcus dividing the internal surface of the occiput into the cerebral fossa superiorly and the cerebellar fossae inferiorly, meets the internal occipital crest separating the left and right cerebellar fossae.
endocast: A cast made of the mold formed by the impression the brain makes on the inside of the neurocranium, providing a replica of the brain with the grosser details of its outer surface. Also called endocranial cast.
endocranium: The inside of the neurocranium.
endogamy: Mating or marriage within a social or cultural unit (cf. exogamy).
endosymbiont hypothesis: The hypothesis that mitochondria and chloroplasts originated as free-living prokaryotes that invaded primative eukaryotic cells and established a mutually beneficial (symbiotic) relationship.
endscraper: A flake tool with retouch on the distal end. The retouched area has an angle that approaches 60º to 90º.
enhancer sequence (enhancer element): In eukaryotes, a type of DNA sequence element having a strong, positive effect on transcription by RNA polymerase II.
environmental sex determination: The process by which the environment plays a major role in determining the sex of an organism.
environmental variance (VE): Any nongenetic source of phenotypic variation among individuals.
eoliths: Crude stone pebbles found in Lower Pleistocene contexts; once thought to be the work of human agency, but now generally regarded as natural products.
epigenetic rule: A regularity occurring during the interaction of genes and environment that channels anatomical, behavioral, or cognitive development in a particular direction.
epimerization: Racemization of the protein amino acid that occurs in eggshells.
epiphysis: A secondary center of ossification (bone formation) usually located at the ends of long bones, separated from the primary center (diaphysis, the shaft) by cartilage growth plates that fuse when bone elongation is completed.
episome: An autonomously replicating plasmid (a circular, double-stranded DNA molecule) that is capable of integrating into the host cell’s chromosome.
epistasis: A form of gene interaction in which one gene interferes with the phenotypic expression of another nonallelic gene so that the phenotype is governed by the former gene and not by the latter gene when both genes are present in the genotype.
epoch: A subdivision of a geological period (e.g., the Pliocene is an epoch in the Tertiary Period).
era: The longest division of geological time, as in the Cenozoic era.
eraillure flake: A small chip detached from the bulb of force.
eruption priorities: Which tooth erupts first of a pair that emerges close together in time.
eruption standards: The patterns of average eruptions in a population.
erythroblasts: Red blood cell precursors.
essential genes: Genes that when mutated can result in a lethal phenotype.
estrus: A time of increased female sexual activity, often accompanied by enhancement of visual or olfactory sexual signals, that occurs at and around the time of ovulation.
ethmoidal sinuses: Air spaces within the ethmoid bone.
ethmoid bone: A small bone in the skull that contributes to the inner orbital wall and also forms a small portion of the floor of the braincase under the frontal bone.
ethnogenesis: The model of biocultural evolution that emphasizes the impermanent nature of social, ethnic, and biological groups (ethnos) in which each population can have multiple ancestors and multiple descendants. Like a river these independently varying aspects of humanity diverge, co-vary in parallel to each other, and then remerge and realign with other identities; with new divergences following.
ethnography: A subset of cultural anthropology concerned with the study of contemporary cultures through first-hand observations.
ethnology: A subset of cultural anthropology concerned with the comparative study of contemporary cultures, with a view to deriving general principles about human society.
euchromatin: Chromatin that is condensed during division but becomes uncoiled during interphase.
eukaryote: A term that literally means “true nucleus.” Eukaryotes are organisms that have cells in which the genetic material is located in a membrane-bound nucleus. Eukaryotes can be unicellular or multicellular.
euploid: The condition in which an organism or cell has one complete set of chromosomes, or an exact multiple of complete sets.
eutherian: Placental mammal.
eversion: Turning outward; for example, of the bottom of the foot.
Eve theory: Sometimes known as “Out of Africa,” or “Out of Africa II” (recognizing that there was an earlier migration from Africa); it is one version of the “Out of Africa” theories stipulating that all modern humans have a common recent origin in an African population that became a new species and swept around the world replacing native peoples.
evolution: Genetic change, change in a population’s gene pool from generation to generation (Darwin’s descent with modification).
evolutionary species: A single monophyletic lineage of ancestral-descendant populations that maintains its identity from other such lineages and that ahs its own evolutionary tendencies and historical fate. Reproductive isolation is implied by this definition, but not explicit in it.
exaptation: The name given for a character that evolved to fulfill a different function than the one it currently serves.
excavation: The principle method of data acquisition in archaeology, involving the systematic uncovering of archaeological remains through the removal of the deposits of soil and the other material covering them and accompanying them.
excision repair (dark repair): An enzyme-catalyzed, light-independent process of repair of ultraviolet-light-induced thymine dimers in DNA that involves removal of the dimers and synthesis of a new piece of DNA complementary to the undamaged strand.
exogamy: Social rules that prescribe mating or marriage outside a social or cultural unit (cf. endogamy).
exon: The part of an mRNA molecule that specifies the amino acid sequence of a polypeptide during translation. See also coding sequence.
expedient behavior: Behaviors and strategies reflected in the archaeological record that serve to solve an immediate problem (cf. curated behavior).
expedient tools: Stone tools made with little or no production effort (see informal tools).
experimental archaeology: The study of past behavioral processes through experimental reconstruction under carefully controlled scientific conditions.
expressivity: The degree to which a particular genotype is expressed in the phenotype.
extant: Living, as opposed to extinct.
extended family: A domestic group or composite of domestic groups consisting of two or more nuclear families linked together through parent and child or through siblings.
extension: Straightening out, a movement in which the angle of a limb joint increases. Opposite of flexion.
extensor: Any muscle that acts to increase the angle between two bones at their joint.
external auditory meatus: The ring of bone surrounding the outer opening for the ear canal.
external occiptal protuberance (eop): See inion.
extinction: The disappearance of a group in part or all of its range.
extramolar sulcus (mandibular): The gutter between the molar teeth and the interior surface of the ascending ramus, for attachment of the buccinator muscle of the cheek.
extrasomatic: Outside the body, nonbiological or nongenetic.
extrasutural bone: Small bone formed within sutures from isolated centers of ossification between major components of the skull vault. Commonly found between occiptal and parietal bones.
Andrefsky, W., Jr. 1998. Lithics: Macroscopic Approaches to Analysis. Cambridge: Cambridge University Press.
Keesing, R.M. 1975. Kin Groups and Social Structure. Fort Worth: Harcourt Brace.
Renfrew, C., and P. Bahn. 1996. Archaeology: Theories, Methods, and Practice. New York: Thames and Hudson Inc.
Russell, P.J. 1998. Genetics. Menlo Park: Addison Wesley Longman, Inc.
Wolpoff, M. 1999. Paleoanthropology. second edition. Boston: McGraw-Hill.