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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.
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