Anthropoid: A member of the group of primates made up of monkeys, apes, and humans.

Australopithecine: A group of bipedal hominid species belonging to the genus Australopithecus that lived between
4.2 and 1.4 mya

Australopithecus Afarensis: An early australopithecine species that was bipedal; known fossils date between 3.6
and 2.9 mya.

Bipedalism: Of hominids & hominoids, walking upright on two hind legs; more generally, using two legs for

Cryptozoology: Study of hidden animals.

Hominids: By definition of Evolution - Members of the family Hominidae, which includes only modern humans and
their ancestors since the human lineage split from the apes.  
By definition of Rationalism - Humans only, does not
include any of primates indigenous to Earth.

Hominoids: Upright walking bi-pedal apes.  Does not include humans.

Homo erectus: A species of hominid that lived between 1.8 mya and 300,000 years ago; the first Homo species to
migrate beyond Africa.

Homo habilis: A species of hominid that lived between 1.9 and 1.8 mya, the first species in genus Homo, and the
first hominid associated with clear evidence of tool manufacture and use.

Homo neanderthalensis: A species of hominid that lived between 150,000 and 30,000 years ago in Europe and
Western Asia, originally thought to be a geographic variant of Homo sapiens but now generally accepted to be a     
distinct species.

Homo sapiens: Modern humans, which evolved to their present form about 100,000 years ago.

Morphology: The study of the form, shape, and structure of organisms.

Neanderthal: A hominid, similar to but distinct from modern humans, that lived in Europe and Western Asia about
150,000 to 30,000 years ago.

Niche: The ecological role of a species; the set of resources it consumes and habitats it occupies.

Paleoanthropologist: A scientist who uses fossil evidence to study early human ancestors.

Paleobiology: The biological study of fossils.

Paleontologist: A scientist who studies fossils to better understand life in prehistoric times.

Paleontology: The scientific study of fossils.

Pheromone: A chemical substance produced by some organisms and emitted into the environment to
communicate with others of the same species. Pheromones play an important role in the social behavior of certain
animals, especially insects and some mammals. They are used to mark out territories, to attract mates, to lay trails,
and to promote social cohesion and coordination in colonies. Examples are the sex attractants secreted by moths
to attract mates and the queen substance produced by queen honeybees, which controls the development and
behavior of worker bees.  Pheromones are usually volatile organic molecules which are effective at very low
concentrations, as little as 1 part per million.

Phylogeny: The study of ancestral relations among species, often illustrated with a "tree of life" branching
diagram, which is also known as a phylogenetic tree.

Primate: A mammal belonging to the order Primates (about 195 species), which includes prosimians, monkeys,
apes, and humans. Primates probably evolved from insectivorous climbing creatures like tree shrews and have many
adaptations for climbing, including five fingers and five toes with opposable first digits (except in the hind feet of
humans). They have well-developed hearing and sight, with forward-facing eyes allowing binocular vision, and large
brains. The young are usually produced singly and undergo a long period of growth and development to the adult
form. Most primates are arboreal, but the great apes and humans are largely terrestrial.

Prosimian: One of the group of primates that includes lemurs and lorises; the other two primate groups are
tarsoids and anthropoids.

Simian:     Relating to, characteristic of, or resembling an ape or a monkey.

Sagittal Crest: A ridge of bone projecting up from the top midline of the skull, running from front to back. It
serves as a muscle attachment area for the muscles that extend up the side of the head from the jaw. The
presence of a sagittal crest indicates extremely strong jaw muscles.

Science: A way of knowing about the natural world based on observations and experiments that can be confirmed
or disproved by other scientists using accepted scientific techniques.

Sexually Dimorphic: When males and females of a species have considerably different appearances, which may
include size, coloration, or other features, such as special plumage.

Speciation: Changes in related organisms to the point where they are different enough to be considered separate
species. This occurs when populations of one species are separated and adapt to their new environment or
conditions (physiological, geographic, or behavioral).

Zygomatic Arch: The bony arch in vertebrates that extends along the side or front of the skull beneath the eye
socket and that is formed by the zygomatic bone and the zygomatic process of the temporal bone.