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of terms related to the biodiversity



parapatric speciation


in which the new species forms from a population contiguous with the ancestral species' geographic range.


An organism which lives on or in another organism, feeding upon it, usually without killing the host.


An insect parasitic only in its immature stages, killing its host in the process of its development, and free living as an adult.


Field-trained biodiversity collection and inventory specialist recruited from local areas.

participatory rural appraisal (PRA)

Also known as Rapid Rural Appraisal, PRA is a relatively new and different approach for conducting action-oriented research in developing countries. PRAs are used to help involve villagers and local official’s leaders in all stages of development work, from the identification of needs and decision making to the assessment of completed projects. The term can be used to describe any new methodology which makes use of a multidisciplinary team.

passive use value


A disease-causing microorganism; a bacterium, fungus or virus.


- A sequence of reactions undergone in a living organism. - Any means that allows the entry or spread of a pest.


(opp.: benthic) Free-swimming (nektonic) or floating (planktonic) organisms that live exclusively in the water column, not on the bottom.


Any species, strain or biotype of plant, animal or pathogenic agent injurious to plants or other organisms and/or their products.

phenotype (see: genotype)

The observed traits (morphological, physiological, biochemical, behavioral, and other properties) of an organism, resulting from an interaction of its genotype and its environment (in contrast to genotype).


- A hormone-like substance secreted into the environment by certain animals, especially insects. - A volatile hormone or behaviour-modifying agent. Normally used to describe sex attractants - for example bombesin for the moth Bombyx - but includes volatile aggression-stimulating agents (e.g. isoamyl acetate in honey bees).


Chemical reactions in plants and plant-like organisms whereby the sun's energy is absorbed by the green pigment chlorophyll, permitting carbon dioxide and water to be synthesized into carbohydrates accompanied by the release of water and oxygen.

phyletic evolution

Genetic changes that occur within an evolutionary line.


Pertaining to the evolutionary history of a particular group of organisms.


History or evolutionary development of any plant or animal species.


In taxonomy and systematics, the highest level of classification below the kingdom. For instance, Mollusca (slugs, snails, clams, squids, etc.) constitute a phylum.


Chemicals found naturally in plants.


Medicinal products based on standardised active ingredients within a herbal base. This term is sometimes used more broadly to include all plant-based medicines.


Naturally-occurring compounds found in fruits and vegetables, such as beta carotene, capsaicin, and flavonoids.


Planktonic organisms ranging in size from 0.2 to 2.0 micrometers.


(opp. nekton) Floating and drifting organisms that have limited swimming abilities and that are carried largely passively with water currents. These include bacteria (bacterioplankton), plants and plant-like organisms (phytoplankton) and the animals (zooplankton) that eat them.

plant functional attributes

Readily observable features of vegetation that are considered significant for growth, physiology and survival (for example pollination mechanisms, seed dispersal mechanisms, rooting systems).


The span of geological time preceding the Recent epochs, during which the human species evolved. It began 2.5 million years ago and ceased with the end of the last Ice Age 10.000 years ago.


Organisms that float on the sea surface.

pollen culture

A culture of plant cells derived from pollen in a synthetic medium: the progeny generated will have a single set of chromosomes.


The transfer of pollen from an anther to the stigma in angiosperms, or from the microsporangium to the micropyle in gymnosperms. Pollination happens when pollen lands on a female part of a flower such as the stigma of a carpel. Pollination can be caused by pollinators(pollinator) such as butterflies, bees, birds, bats but also by the wind or the water.


A pollinator is an agent, generally an animal (insect, bird, bat, etc.) that carries pollen to the female part of a flower.


Organism containing two or more sets of genes(gene) or chromosomes.


A group of individuals with common ancestry that are much more likely to mate with one another than with individuals from another such group.

population and habitat viability assessment (PHVA)

The theoretical modeling of minimum areas, habitat types and population sizes, to sustain any one or more species. Population size will be determined by the carrying capacity of the habitat.

population viability analysis (PVA)

- The theoretical determination of the minimum viable (in terms of genetic make-up) breeding population for any one species to survive in a given range. - A comprehensive analysis of the many environmental and demographic factors that affect survival of a population, usually small.


A herbicide which acts after the seed has germinated.


The development of germplasm to a state where it is viable for breeder's use. Primarily involves the evaluation of traits from exotic material and their introduction into more cultivated backgrounds.

pre-clinical studies

The various tests conducted in whole animals and other test systems, such as cell cultures, to determine the relative toxicity of a compound to living systems. These are referred to as pre-clinical studies - tests conducted and evaluated prior to the first administration of the compound to humans. Also included in this category are two-year carcinogenicity assays which typically overlap with the chemical testing phase. Pre-clinical tests include: toxicity (how poisonous it is and what side effects might be expected); bioavailability (how effectively it is taken up into the body and delivered to the tissue where it is needed); pharmacokinetics (how it is metabolised, and therefore how long it stays in the body, and whether it has the desired physiological effect).

precautionary principle (= do-no-harm principle) (opp.: wait-and-see principle)

- A proactive method of dealing with the environment (= do-no-harm principle) that places the burden of proof on those whose activities could harm the environment. - If the costs of current activities are uncertain, but are potentially both high and irreversible, the precautionary principle holds that society should take action before the uncertainty is resolved.


A natural enemy that preys and feeds on other animal organisms, more than one of which are killed during its lifetime.

predator control

A predator - prey interaction in which the predator controls the prey population size, that is in which the predator population is the limiting factor for the prey population size.

primary forest

(also: natural forest, opp.: secondary forest) A forest largely undisturbed by human activities.

primary metabolites

Compounds ubiquitous in living organisms and essential for life, such as carbohydrates, the essential amino acids and polymers derived from them.

primary production

Amount of organic material synthesised by organisms from inorganic substrata in a given area in a given period.

primary productivity

The transformation of chemical or solar energy to biomass. Most primary production occurs through photosynthesis, whereby green plants convert solar energy, carbon dioxide, and water to glucose and eventually to plant tissue. In addition, some bacteria(bacterium) in the deep sea can convert chemical energy to biomass through chemosynthesis.

primary value

The value of the system characteristics upon which all ecosystem functions depend.

primitive cultivar

Crop form developed from landrace. Improvement through selection restricted to a few specific characteristics and often more uniform in nature than a landrace.

production environment

All input-output relationships, over time, at a particular location. The relationships will include biological, climatic, economic, social, cultural and political factors, which combine to determine the productive potential of a particular livestock enterprise. - high-input production environment;- medium-input production environment;- low-input production environment.

production function

This describes the outputs that may be obtained from combining different quantities of inputs.

production traits

Characteristics of animals, such as the quantity or quality of the milk, meat, fiber, eggs, draught, etc. they (or their progeny) produce, which contribute directly to the value of the animals for the farmer, and that are identifiable or measurable at the individual level. Production traits of farm animals are generally quantitatively inherited, i.e. they are influenced by many genes(gene) whose expression in a particular animal also reflects environmental influences.

progeny testing

Procedure to establish the genotype of a parent by recording the genetic status of offspring/progeny.

prokaryote (opp.: eukaryote)

An organism having a cell without a distinct nucleus. Bacteria and blue-green algae are prokaryotes.


A dispersal stage of a plant or animal, such as fertilized eggs, larvae, or seeds.

protected area

- A geographically defined and legally established land or water area under either public or private ownership that is designated, regulated and managed to achieve specific conservation objectives. - An area of land and/or sea especially dedicated to the protection and maintenance of biological diversity, and of natural and associated cultural resources, and managed through legal or other effective means.

protein engineering

The generation of proteins(protein) (specifically enzymes) with subtly modified structures, thus conferring new properties such as changed catalytic specificity or thermal stability.


A plant cell from which the cell wall has been removed by mechanical or enzymatic means. Protoplasts can be prepared from primary tissues of most plant organs as well as from cultured plant cells.

provinciality effect

Increased diversity of species because of geographical isolation.

public good

A good which, once provided to one user, must be provided in the same amount to all users due to its non-rival and non-excludable nature.

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