Biodiversity publications archive

Australia's biodiversity: an overview of selected significant components

Biodiversity series, Paper no. 2
Biodiversity Unit
Department of the Environment, Sport and Territories
, 1994

Glossary

Words typed in bold in the explanatory text are also explained in the glossary.

adaptive radiation
The evolution from one ancestral form of a range of distinct but related species occupying a variety of different types of available habitats and ecological niches. (See also explosive radiation)
allopatric
(Of two or more closely related species, or populations within the same species) existing in geographical isolation from each other (cf sympatric-existing together in the same or overlapping areas).
amphipod
Crustacean of the order Amphipoda (including shrimps and sand hoppers).
angiosperm
Flowering plant-i.e. any plant in which seeds are borne enclosed in an ovary. (See also gymnosperm)
anostracan
Crustacean of the suborder Anostraca (the fairy or brine shrimps).
Antarctic Convergence
The zone, roughly midway between the Antarctic coast and the other southern continental landmasses, in which the very cold waters of the Antarctic zone mix with the cold waters of the sub-Antarctic zone.
basal
(Of a taxonomic group) thought to be closely related to an ancestral form from which modern highly evolved groups have arisen.
benthic
Relating to organisms living on or in the bed of a sea or lake.
bony fishes
Fishes of the class Osteichthyes, which have bony skeletons.
buthid
Scorpions of the family Buthidae.
canopy
The cover produced by the leaves and branches of woody plants, particularly trees, forming the uppermost light-restricting area in a plant community.
cay
A small, flat island composed of a bank of sand overlying a coral reef, just above high tide level.
chironomid
Fly of the family Chironomidae (midges).
choanichthyid
Fish of the group closely related to the basic stock from which amphibians arose. The group includes the present-day lungfish and coelacanths.
cladoceran
Crustacean of the order Cladocera (water fleas).
co-evolution
The evolution of phylogenetically unrelated organisms that has taken place together because of a special ecological association between them.
community
A group of organisms inhabiting a common environment and interacting with one another (through food and other (ecological/biotic) relationships) as a self-contained unit, relatively independent of adjacent communities.
conchostracan
Crustacean of the suborder Conchostraca (clam shrimps).
conilurine rodents
Rodents of the tribe Conilurini, including rabbit rats, hopping mice, plains rats and stick-nest rats.
convergent evolution (convergence)
The independent development of similarities of form between groups of organisms that are not closely related, usually as a result of adaptation to similar environments or life cycles. For example, echidnas, porcupines and hedgehogs (each belonging to a different order of mammals) have independently evolved protective coverings of spines on their bodies. (See also divergence)
copepod
Crustacean of the subclass Copepoda. Copepods are an important constituent of both marine and freshwater plankton.
coppice
Shoots or shooting developing from dormant buds in the trunk or major branches of a tree.
crustose coralline
A group of very abundant algae, the plant
algae
bodies of which are entirely calcified, and which as a group, are essential to the structure and thus survival of coral reefs.
cyanobacterium (or blue-green alga)
Organism belonging to the phylum Cyanophyta. Like bacteria, cyanobacteria are unicellular and lack a distinct cell nucleus, but differ in being able to photosynthesise.
cycad
Member of the order Cycadales, tropical and subtropical palm-like gymnosperms, of ancient lineage.
detritus
Any organic debris.
diplodactyline geckos
Geckos of the tribe Diplodactylini (genera Diplodactylus, Rhynchoedura, Strophurus and Crenadactylus), which is one of two tribes of the subfamily Diplodactylinae.
disjunct distribution
Having a broken distribution, where two or more species of a genus occur in geographical isolation from one another (sometimes even on different continents).
divergence
Evolution of different species from a common ancestral form. (See also convergent evolution, adaptive radiation)
echinoderm
Organism of the phylum Echinodermata, which includes starfish, brittle stars, feather stars, sea urchins, sea cucumbers and sea lilies.
ecological niche
The environmental and biological conditions, locations and functions within which an individual, population or species is able to exist in an ecosystem.
ecosystem
A dynamic complex of plant, animal, fungal and microorganism communities and associated non-living environment, interacting as an ecological unit.
endemic
Restricted to a specified region or locality.
epiphyte
(Normally) a plant growing on, but not parasitic on, another plant. Also used loosely for plants such as many orchids, which grow on vertical rock faces, and marine animals which grow on marine plants.
eurytopic
Of a species: tolerant of a wide range of ecological conditions.
explosive radiation
Diversification or adaptive radiation of a group-e.g. the diversification of the mammals at the beginning of the Cainozoic Era (about 65 million years ago).
fen
A plant community on wet, low-lying peat.
filamentous seaweed
Seaweed in which the cells are organised in thread-like rows.
galls
Abnormal growths of plant tissue produced in response to irritation or attack by insects, mites, eel worms, fungi or microorganisms.
gastropod
Mollusc of the class Gastropoda (snails, slugs, univalve shellfish and sea slugs).
gymnosperm
A plant in which the seeds are borne uncovered on the surface of modified leaves (which often take the form of cones). (See also angiosperm)
heath
A lowland shrub community on sandy soil or shallow peat.
herbfield
A plant community dominated by non-woody vascular plants whose above-ground parts do not persist beyond the end of the growing season.
hydrobiid snail
Gastropod of the family Hydrobiidae.
insectivore
Insect-eating organism.
interglacial period
A period of comparatively warm climate between two glacial stages, especially of the Pleistocene epoch.
isopod
Crustacean of the order Isopoda, which includes woodlice and pill bugs. They are characterised by seven equal pairs of legs.
lerp
Scales formed as protective coverings on eucalypts by some bugs of the subfamily Spondyliaspidinae (family Psyllidae). Lerps can take various shapes and are formed largely from honeydew.
macroalga
Alga visible to the naked eye.
macrophyte
Plants, including algae, which are visible to the naked eye.
malacostracan
Crustacean of the group Malacostraca, (including crabs, lobsters, crayfish and shrimps).
mallee
Growth habit in which several woody stems arise separately from a lignotuber. The term is generally applied to shrubby eucalypts. It can also refer to the ecosystems, characteristic of inland Australia, dominated by such eucalypts.
megafauna
Large animals, particularly those now extinct.
megascolecid
Earthworms of the family Megascolecidae.
microbiotheriids
Ancient marsupials of the family Microbiotheriidae, from which the modern Australian marsupials arose.
mollusc
Member of the phylum Mollusca, including snails, bivalves, squids and octopuses
monotreme
Any mammal of the order Monotremata (platypuses and echidnas). (See also placental)
monotypic
(Of a taxon ) containing only one subordinate taxon (e.g. a genus with only one species).
morphology
(The study of) the shape, form or structure of an organism.
nectivore
Animal that feeds on nectar.
notostracan
Crustacean of the order Notostraca (shield shrimps).
oniscoid
Crustacean of the suborder Oniscoidea (order Isopoda)
onychophoran
Animal of the phylum Onychophora (velvet worms).
orthopteran
Insect of the order Orthoptera (grasshoppers, locusts, katydids and crickets).
osmoregulation
The control of osmotic potential in organisms, in order to achieve a correct water balance. Osmotic potential is a measure of the tendency of a solution to withdraw water from pure water across a permeable membrane (such as a cell wall) by osmosis.
ostracod
Crustacean of the order Ostracoda, the seed or shell shrimps.
palaeoaustral
Relating to faunal and floral groups peculiar to the (high latitude) shores of Gondwana during the Cretaceous period.
penaeid prawns
Crustaceans of the family Penaeidae, including king prawns.
phenotypically
Of or relating to the total observable characteristics of an organism (its phenotype), which result from the interaction between its genetic make-up (genotype) and its environment.
phylogenetic
Pertaining to the evolutionary history of a particular group of organisms.
phyllode
A leaf in which the blade is greatly reduced or absent, and the stalk, or petiole, is generally flattened, and performs the functions of the whole leaf.
phytophagous
Feeding on plants.
placental
Mammals having a well-developed placenta and bearing fully-formed young (i.e. the majority of living mammals).
planigale
Small carnivorous marsupials of the subfamily Planigalinae (family Dasyuridae). All belong to the genus Planigale.
plate tectonics
The scientific concept that the surface of the Earth consists of a number of crustal plates (tectonic plates) which move around driven by convection currents in the molten mantle beneath.
proteaceous
Of or relating to plants of the mainly southern hemisphere family Proteaceae. Among the more familiar are the waratahs, banksias, grevilleas and hakeas.
proteoid roots
Clumps of short, usually short-lived roots common in proteaceous species, believed to be formed with the assistance of soil bacteria. Having a larger absorptive surface than normal roots, they are very efficient at absorbing moisture and nutrients and appear to be an adaptation to nutrient-deficient soils.
ratite birds
Flightless birds lacking a keel on the breastbone for the attachment of flight muscles; they include ostriches, emus, cassowaries, rheas and kiwis.
recruitment
Successful incorporation of offspring into a population.
refuges
are areas where wildlife can find sanctuaries for breeding and feeding.
relict
A surviving individual, population, community or species that is characteristic of an earlier period in evolutionary history.
rotifer
Animal of the phylum Rotifera.
saprophage
Organism that feeds on dead or decaying matter.
sclerophylly
(In plants) the possession of leaves (or stems if leafless) that are tough, hard, and usually fibrous with a thick cuticle (waxy coating), sometimes accompanied by small plant size.
scorpionid
Scorpions of the family Scorpionidae.
senesce
To grow old (especially with respect to trees and shrubs). Senescence is accompanied by a gradual slowing down of metabolism and breakdown of tissue.
speciation
The process by which new species are formed, involving genetic isolation of populations and adaptation.
species richness
The number of species in a defined area.
speciose
Consisting of numerous species.
stenopelmatid
Insect of the family Stenopelmatidae, which includes king crickets.
steppe grassland
Grassland dominated by short grasses, as compared to prairie grassland, which is dominated by long grasses.
stomata
(Singular: stoma) The pores in the epidermis of a leaf allowing gas exchange between the tissues and the atmosphere.
subendemic
Almost entirely endemic.
syncarid
Crustacean of the largely freshwater superorder Syncarida.
taxon
The named classification unit to which individuals, or sets of species, are assigned, such as species, genus, order, etc.
tectonic plate
See plate tectonics.
Tethyan
Of or relating to the Tethys Sea, the large tropical ocean that partly divided Pangaea in Jurassic to Cretacean times.
trichopteran
Insect of the order Trichoptera (caddis flies).
trophic interactions
Interactions involving the transfer of nutrients and energy, particularly feeding interactions between different organisms within a community.
vascular plants
Plants of the phylum Tracheophyta. They include all angiosperms, gymnosperms and pteridophytes (ferns and their allies)-i.e. all large land plants.
zooplankton
The part of plankton made up of animal life (cf. phytoplankton, which is the part of plankton made up of plant life).