A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
a common type of fine-grained igneous rock formed from solidified molten lava; typically composed of dark colored minerals including plagioclase, pyroxene and olivine.
base pair
the four bases in DNA: adenine (A), guanine (G), thymine (T), and cytosine (C). During the replication process, adenine bonds with thymine (A-T), and cytosine bonds with guanine (C-G), if there are no mutations.
a single layer of sediment.
the arrangement of different sediments or rock layers.
a clay that forms from the weathering of volcanic ash.
[syn. The Bering Land Bridge or Bering Straight] a now submerged portion of the continental shelf about 1,000 miles wide located between Northeast Siberia and the western coast of Alaska. Many archaeologists believe humans used this route to cross into North America when sea levels were much lower.
bicondylar angle
the angle at which the shaft of the femur sits relative to the perpendicular midline of the body.
A stone tool that has been worked on both sides (i.e., faces).
paired elements present on both the left and right side of the body, or a condition that effects both sides of the body.
A tool for soft percussion, typically made of antler or wood.
a cusp pattern where ridges (i.e., lophes) are present between the pair of mesial and distal molar cusps.
binomial nomenclature
the scientific name of an organism consisting of two taxonomic terms (i.e., the genus and species name). The binomial nomenclature for modern humans is Homo sapiens.
biological diversity
[syn. biodiversity] the different environments and species on the earth; the genetic variability seen in life.

a form of positional behavior (i.e., posture and locomotion) that utilizes only the hind limbs; an animal that locomotes on two legs is referred to as a biped. See also facultative bipedalism and habitual bipedalism.


a stone tool with a length that is twice its width; usually hafted into bone or wooden implements.

body fossil
a fossilized skeleton or other hard morphology of a multicelluar organism.
arboreal locomotion in which the body is suspended under the hands, legs or tail, and locomotion is propelled by the arms swinging alternately and grasping branches. Apes and humans are able to brachiate.
branching event
a point on the evolutionary lineage of an organism which diverges, or splits off, from the ancestral line into a new evolutionary lineage as a result of numerous unique adaptations.
angular stone, sand, or bone that has been implanted in the ground. Breccia is found in many South African hominid sites, such as Taung.
Broca's area
area of the brain located on the left side of the fontal lobe responsible for the production of speech, including muscle control of the mouth, tongue and larynx.
brow ridge

[syn. supraorbital torus] the bony protrusion above the eye orbit seen in many primates. The brow ridge is very pronounced in Archaic Homo sapiens (i.e., H. heidelbergensis) and H. neanderthalensis.


term used for elements in the mouth closest to the cheek.

bulb of percussion
the point on a lithic (i.e., stone tool) that was struck and can be visualized as swelling on the striking platform surrounded by ripples.

premolars and molars that have low, rounded cusps.

A flake with a chisel-like edge, possibly used for engraving or carving wood/bone.