Archaeology & Evolution Glossary (H)

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


 
habiline: Referring to the Homo species of Homo habilis and Homo rudolfensis.

habitat: The normal home or environment of a group.

hackle marks: See fissures.

hafting: Attaching, for instance when a bone or stone point is attached to a wood shaft.

half-life: The length of time in which one-half of the nuclei of an unstable isotope of an element decay into smaller nuclei (releasing energy).

hallux: First digit on the foot (big toe).

hammerstone: A rock used as a percussor to detach flakes from an objective piece. These usually show signs of impact damage such as crushed edges.

hamstrings: A group of muscles including biceps femoris, semimembranosus, and semitendinosus, extending from the ischial tuberosity to the back of the femur and top of the tibia, mainly acting to flex the hip joint.

hand axe: A teardrop or pear shaped, bifacially flaked stone implement.

haploid: Having only a single set of chromosomes, half the number in a normal somatic cell. Gametes are normally haploid.

haplotype (N): Sets of genes at more that one locus.

hard hammer: A hammerstone made of hard rock.

Hardy-Weinberg law (Hardy-Weinberg equilibrium, Hardy-Weinberg law of genetic equilibrium): A extension of Mendel’s laws of inheritance that describes the expected relationship between gene frequencies in natural populations and the frequencies of individuals of various genotypes in the same populations.

harlequin chromosomes: 5-bromodeoxyuridine (5-BUdR), a thymidine analog, is incorporated into DNA during replication. When both DNA strands contain 5-BUdR, the chromatid stains less intensely than when only one DNA strand contains the analog. When cells are grown in the presence of 5-BUdR for two replication cycles, the two sister chromatids stained differentially are called harlequin chromosomes.

hearth: A circle of stones enclosing a camp fire that focuses, contains, and sustains its heat.

helix-destabilizing proteins: See single-strand DNA-binding (SSB) proteins.

hemisphere: One of the two sides of the cerebrum.

hemizygous: The condition of X-linked genes in males. Males that have an X-chromosome with an allele for a particular gene but do not have another allele of that gene in the gene complement are hemizygous.

herbivore (herbivorous): Plant-eater.

hereditary traint: A characteristic under control of the genes that is transmitted from one generation to another.

heritability: A measure of the extent to which a feature is inherited; that proportion of variation of a trait in a population that is due to the variation of genotypes.

hermaphroditic: For animals (e.g., nematode), the species in which each individual has both testes and ovaries; in plants, the species that have both stamens and pistils on the same flower.

herniate: Protrude from an abnormal opening.

Hertzian cone: The cone formed as a result of conchoidal fracture in brittle solids.

hetero-: Different.

heterochromatin: Chromatin that remains condensed throughout the cell cycle and is generally inactive.

heterochrony: Evolutionary changes caused by variation in the relative time of appearance and rate of development of features.

heterodontic: Teeth of the same type (for instance incisors, premolars, etc.) that differ in size or form.

heterogametic sex: The sex that has sex chromosomes of different types (e.g., XY) and therefore produces two kinds of gametes with respect to the sex chromosomes.

heterogenous nuclear RNA (hnRNA): The RNA molecules of various sizes that exist in a large population in the nucleus. Some of the RNA molecules are precursors to mature mRNAs.

heterokaryon: A cell or collection of cells (as in a mycelium) possessing genetically different nuclei (regardless of their number) in a common cytoplasm.

heteromorphic: The occurrence of two different alleles at a particular locus.

heteroplasmy: Extranuclear inheritence, usually in reference to the inheritence of mtDNA from the father.

heterosis: The phenomenon in which the heterozygous genotypes with respect to one or more characters are superior in comparison with the corresponding homozygous genotypes in terms of growth, survival, phenotypic expression, and fertility.

heterozygosity: The proportion of individuals heterozygous at a locus; the state of being heterozygous. See also heterozygous.

heterozygote: A form of a polymorphism controlled by different alleles at a locus.

heterozygote advantage: See overdominance.

heterozygous: A term describing a diploid organism having different alleles of one or more genes and therefore producing gametes of different genotypes.

Hfr (high-frequency recombination): A male cell in E. coli with the F factor integrated into the bacterial chromosome. When the F factor promotes conjunction with a female (F-) cell, bacterial genes are transferred to the female cell with high frequency.

higher primate: Anthropoid.

highly repetitive sequence: A DNA sequence that is repeated between 105 and 107 times in the genome.

hinge fracture: The scar left by a previously removed flake detached by hinge termination.

hinge termination: The distal end of a flake that is rounded or blunted.

histone: One of a class of basic proteins that are complexed with DNA in chromosomes and that play a major role in determining the structure of eukaryotic nuclear chromosomes.

hoards: Deliberately buried groups of valuables or prized possessions, often in times of conflict or war, and which, for one reason or another, have not been reclaimed.

holism: Theoretical approach which, when applied ot human societies, sees changes as the product of large-scale environmental, economic, and social forces with the assumption that what individual humans wish, desire, believe, or will is not a significant factor.

home base: A particular place where individuals can expect to meet each other and engage in social and other activities.

homeobox: A 180-bp consenus sequence found in the protein-coding sequences of genes that regulate development.

homeodomain: The 60-amino-acid part of proteins that corresponds to the homeobox sequence of genes. All homeodomain-containing proteins appear to be located in the nucleus.

homeostasis: A term used in systems thinking to describe the action of negative feedback processes in maintaining the system at a constant equilibrium state.

homeotic mutations: Mutations that alter the identity of particular segments, transforming them into copies of other segments.

home range: The area within which a group of primates usually moves over the course of their yearly cycle.

hominid: Extant humans and their unique ancestors and collateral relatives, extending back in time until the split with the line leading to chimpanzees (the closest living human relative).

hominoid: Member of Hominoidea, the superfamily including humans and apes and their unique ancestors.

homo-: Same.

homodontic: Teeth of the same type with similar anatomy.

homogametic sex: The gender in the species, most often the female, that produces only the X sex chromosomes.

homolog: Each individual member of a pair of homologous chromosomes.

homologous chromosomes: The members of a chromosome pair that are identical in the arrangement of genes they contain and in their visible structure.

homologue: A homologous structure.

homology: A feature in two or more species that is the same because of descent, it evolved from the same feature in the last common ancestor of the species.

homoplasy (parallelism): The separate appearance of a feature with the same character state in two or more species that developed independently from a different character state of the feature in the last common ancestor.

homozygosity: The occurence of two identical alleles at a locus.

homozygote: A festure controlled by a locus at which the two alleles are the same.

homozygous: A term describing a diploid organism having the same alleles at one or more genes and therefore producing gametes of identical genotypes.

homozygous dominant: A diploid organism that has the same dominant allele for a given gene locus on both members of a homologous pair of chromosomes.

homozygous recessive: A diploid organism that has the same recessive allele for a given gene locus on both members of a homologous pair of chromosomes.

honing facet: A worn surface with a sharp edge on the front or back of a tooth that sildes against a similar facet on the opposing tooth in the opposite jaw, producing a scissors-like cutting action.

horizon: A particular stratigraphic level or time interval, definable geologically or by the fauna or artifacts in it.

human genome project: A project to obtain the sequence of the complete 3 billion (3 x 109) nucleotide pairs of the human genome, and to map all of the estimated 50,000 to 100,000 human genes.

Humerofemoral Index: Ratio of the length of the humerus divided by the length of the femur X 100.

humerus: Long bone of the upper arm.

hunter-gatherers: Populations that live by hunting (and often scavenging dead) animals, gathering plant foods, insects and other small and relatively sedentary animals, and sharing the fruits of these planned economic activities.

hybrid dysgenesis: The appearance of a series of defects, including mutataions, chromosomal aberrations, and sterility, when certain strains of Drosophila melanogaster are crossed.

hyoid: Small U-shaped bone of the throat supporting the vocal chords, and the site of the muscle attachments functioning in the control of fine movements of the lower jaw.

hypersensitive sites (hypersensitive regions): Sites in the regions of DNA around transcriptionally active genes that are highly sensitive to digestion by DNase I.

hypervitaminosis: A condition resulting from a dietary excess of the vitamin concerned.

hypoplasia: Interrupted enamel formation, leaving transverse lines, pits, or grooves visible on the enamel surface.

hypothetico-deductive method: Research method involving making observations, forming hypotheses to explain the observations, making experimental predictions based on the hypotheses, and, finally, testing the predictions. The last step produces new observations and so a cycle is set up leading to a refinement of the hypotheses and perhaps eventually to the establishment of a law or an accepted principle.

hypsodont: Having teeth with tall crowns, as in horses or Gigantopithecus.

Bibliography

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.