Glossary

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talonid
the extraneous area formed by the entoconid, the hypoconid and sometimes the hypoconulid on the distal portion of the lower molar.
taphonomy

the study of the events and conditions that led to the fossilization and preservation of a particular specimen or assemblage of specimens.

Taung Child
the name for the first Australopithecine fossil ever identified that consisted of juvenile endocast; found in a rock quarry in 1924 by Raymond Dart, it was name Australopithecus africanus (i.e. "African southern ape"). The inferior placement of the foramen magnum on the Taung child fossil indicates that A. africanus was bipedal.
taxon
a category (e.g., species, genus, family, and order) in the classification of organisms.
taxonomy

the process of applying appropriate and correct names for organisms, usually, but not always, on the basis of evolutionary relationships.

tectonic activity
activities that can be attributed to moving of the earth's tectonic plates, including earthquakes, volcanic eruptions, continental rifting, etc.
temperate zone

the region north of the Tropic of Cancer (23.5 degrees north latitude) or south of the Tropic of Capricorn (23.5 degrees south latitude).

temporal
located at the lateral base of the skull; surrounded the external ear.
temporal foramen
the space bounded by the cranium (medially) and the zygomatic arch (laterally) through which the temporalis muscle passes to its insertion on the coronoid process of the mandible.
temporal fossa
the space (or depression) on the skull occupied by the temporal muscle.
Term
Definition
terrestrial

of the ground.

terrestrial quadrupedalism

a mode of locomotion in which the animal moves along the ground with a regular gait pattern involving all four limbs. See also arboreal quadrupedalism.

territory
part of an organism's home range that is defended against invasion by other groups, particularly those of the same species.
Tertiary
a period in the Cenozoic era on the geologic time scale that approximately dates from 65 million years ago to 1.6 million years ago; includes the Paleocene, Eocene, Oligocene, Miocene and Pliocene epochs.
Tethys Sea
a sea that separated the northern (i.e., Laurasia) and southern (i.e., Gomdwana) portions of Pangea that approximately dates between 280 million years ago and 55 million years ago; marked by its biodiversity.
theory
a tested hypotheses that describes an observable fact or facts. A theory usually consists of an abundance of related ideas and explanations verified to be true through various and repeatable experiments and observations.
thoracic vertebrae
the section of the vertebral column where the ribs attach. Modern humans have twelve thoracic vertebrae.
thorax
the chest region that usually houses the lungs, heart, esophagus and related structures.
trabecular bone
an interior web of bone that acts to reinforce the bones strength and stability; typically found near the ends of long bones and in between the cortex of flat bones. The structure of trabecular bone can be studied to determine an animal's habitual physical behaviors.
trace fossil
evidence of an animal's activities preserved in the fossil record; may consist of preserved footprints, tunnels, coprolites, tracks, etc.
transcription

the production of a single strand of messenger RNA (mRNA) from a double-stranded sequence of DNA; the first part of the process of creating proteins from genes.

transitional fossil
a fossil that exhibits primitive features of an ancestral species and the derived features of a descendant species.
translation

the conversion of messenger RNA (mRNA) into a chain of amino acids that make up a protein that is coded for by the gene; the final step of the process of creating proteins from genes.

translocation
when a piece of a chromosome gets detached and is reattached in an inappropriate chromosome, resulting in a mutation.
Triassic
a period in the Mesozoic era on the geologic time scale that approximately dates from 245 million years ago to 200 million years ago; marked by presence of the first dinosaurs and mammals, and the diversification of shelled cephalopods.
trigon
the triangle formed by the protocone, paracone and metacone on the upper molar.
trigonid
the triangle formed by the protocone, paracone and metacone on the mesial portion of the lower molar.
trisomy
having three copies of a specific chromosome instead of two.
tropical zone

the region between the Tropic of Cancer (23.5 degrees north latitude) and south of the Tropic of Capricorn (23.5 degrees south latitude).

trunk
the torso of the body; place where appendages, head and/or tail attach.
tuberosity
a rugged or robust protuberance on a bone.
tuff
sediments deposited by volcanic ash after an eruption.
type specimen
one individual specimen that is used as the representative for a species
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