Biodiversity - Module 4

Adaptation

A feature of an organism that increases its chance of survival in its environment.

An adaptation may be anatomical, physiological or behavioural.

Belt transect

A line along a sampled area upon which quadrats are placed at intervals to

determine the abundance and distribution of organisms in an ecosystem.

Binomial system

The universal system of naming organisms. It is made up of two parts; the

first gives the genus and the second, the species e.g. Homo sapiens .

Biodiversity

The variety of living organisms in an ecosystem.

Charles Darwin

The scientist who developed the theory of evolution by natural selection.

Classification

The organisation of organisms into groups.

Community

All of the populations of different species living together in a habitat.

Conservation

The maintenance of ecosystems and biodiversity by humans in order to

preserve the Earth’s resources.

Continuous variation

When a characteristic can have any value within a given range e.g.

height, mass, heart rate.

Convention on Biological Diversity (CBD)

A treaty that promotes the sustainable use of

and maintenance of biodiversity. One of three Rio Conventions.

Convention on International Trade in Endangered Species (CITES)

A treaty that

regulates the trade of plants and wild animals across international borders.

Convergent evolution

The process by which unrelated species evolve similar traits due to

exposure to similar environments or selection pressures.

Countryside Stewardship Scheme (CSS)

A scheme in England (1991-2014) that aimed to

provide financial incentives to farmers to enhance and conserve the environment. Replaced

by the Environmental Stewardship Scheme (ESS).

Discontinuous variation

When a characteristic can only take certain values e.g. sex, eye

colour, blood group.

Domain

The highest taxonomic rank. There are three domains; Archaea, Bacteria and

Eukaryota.

Evolution

The gradual change in the allele frequencies within a population over time.

Occurs due to natural selection.

Ex situ conservation

A type of conservation that takes place outside of an organism’s

natural habitat e.g. zoos, botanic gardens, seed banks.

Fossil

The remains of dead organisms found in rocks which are millions of years old.

Fungi

A biological kingdom consisting of mushrooms, yeasts and moulds.

Genetic biodiversity

A measure of the variety of genes that make up a species.

Habitat biodiversity

A measure of the number of different habitats found within an area.

In situ conservation

A type of conservation that takes place within an organism’s natural

habitat e.g. wildlife reserves, marine conservation zones.

Interspecific variation

Differences between members of different species.

Intraspecific variation

Differences between members of the same species.

Keystone species

A species which has an unexpectedly large effect on the environment

and is crucial for the maintenance of biodiversity.

Kick-sampling

A method used to sample organisms living on the bed of a river. It involves

disturbing an area of river bed before placing a net downstream to capture released

organisms.

Kingdom

The second highest taxonomic rank. There are five kingdoms

Protoctista, Fungi, Plantae and Animalia.

Line transect

A line along a sampled area. The species touching the transect at regular

intervals are recorded to determine the abundance and distribution of organisms in an

ecosystem.

Monoculture

The growth of one crop in a given area.

Natural selection

The process by which the frequency of ‘advantageous’ alleles gradually

increases in a population’s gene pool over time.

Non-random sampling

A sampling method in which a sample is not chosen randomly.

Three types; opportunistic, stratified and systematic.

Opportunistic sampling

A type of non-random sampling that involves drawing a sample

from part of the population that is conveniently available.

Phylogenetic tree

A diagram used to show the evolutionary relationships between

organisms.

Phylogeny

The evolutionary relationships between individuals or groups of organisms.

Pitfall trap

A device used to catch small ground surface invertebrates. It consists of a

container buried beneath the ground and a roof structure.

Pooters

A device used in the collection of small insects. It consists of two tubes, one

connecting the holding chamber to a mouthpiece (with a filter) and the other to an inlet tube.

Prokaryotae

A biological kingdom consisting of unicellular prokaryotes (bacteria).

Proportion of polymorphic gene loci

A measure of genetic biodiversity. Calculated using

Protoctista

A biological kingdom consisting of unicellular eukaryotes.

Quadrat

A square grid of known area used in sampling to determine the abundance of

organisms in a habitat. There are two types; point quadrats and frame quadrats.

Random sampling

A sampling technique used to avoid bias e.g. creating a square grid and

generating random coordinates.

Seed bank

A storage of seeds to preserve genetic material.

Selection pressures

Environmental factors that drive evolution by natural selection and

limit population sizes e.g. competition, predation and disease.

Simpson’s Index of Diversity ( D )

A measurement of diversity that considers both species

richness and evenness. Calculated using the formula

Spearman’s rank correlation coefficient

A statistical test used to determine the

relationship between two variables.

Species biodiversity

A measure of species richness and species evenness.

Species evenness

The number of individuals of each species living together in a

community.

Species richness

The number of different species found within an area.

Stratified sampling

A type of non-random sampling in which populations are divided into

strata and a random sample is taken from each, proportional to its size.

Student’s t-test

A statistical test used to analyse whether there is a significant difference

between the means of data values of two populations.

Sweep nets

A funnel-shaped net used to catch insects and other small animals.

Systematic sampling

A type of non-random sampling in which samples are taken from

different regions of a habitat.

Taxon

Each group within a phylogenetic classification system.

Taxonomic hierarchy

The arrangement of organisms into successive levels of

classification known as taxonomic groups.

Three-domain system

A method of classification in which organisms are categorised into

three domains and six kingdoms. Developed by Carl Woese.

Tullgren funnel

A device used to extract living organisms from a soil sample.

Variation

The differences between individuals due to genes, the environment or a

combination of both.