actinomorphic Having flowers with radial
symmetry.
adaptive radiation The evolutionary process by
which an ancestral species gives rise to an array of
descendant species exhibiting great ecological,
morphological or behavioural diversity.
alien species A foreign (exotic, or non-native)
species moved by humans to a region outside its
natural geographical range or environment.
alleles Two or more forms of a gene occupying
the same locus on a chromosome.
allelopathyA form of interference competition by
means of compounds produced by one species of
plant that reduce the germination, establishment,
growth, survival, or fecundity of another plant species.
allochthonous Having originated outside the
area where it now occurs.
allogamy Fertilization involving pollen and
ovules from: (1) different flowers (whether on the
same plant or not); (2) genetically distinct individu-
als of the same species.
allopatric speciation The differentiation of geo-
graphically isolated populations into distinct species.
allozyme One of several forms of an enzyme
coded for by different alleles at a locus.
anacladogenesis Evolutionary change within a
lineage where the progenitor species survives with
little change alongside the derived species.
anagenesis Evolutionary change within a lineage
where the progenitor species becomes extinct.
anemochory Dispersal by wind.
anemophily Pollination by wind.
area cladogram A cladogram in which the termi-
nal taxa have been replaced by their respective geo-
graphical distributions.
assemblage The set of plant or animal species
found in a specific geographical unit or area.
assembly rules Identified structure in the
composition of a series of islands (or other
operational units), typically determined within eco-
logical guilds. Assembly rules include: (1) compati-
bility rules, (2) incidence rules, and (3) combination
rules.
assortative equilibrium In the context of the
equilibrium theory of island biogeography, the
species number having initially equilibrated, may
increase over time to a new equilibrium value
reflecting the ecological interactions within the
biota.
atoll Coral reefs built around subsiding volca-
noes.
auto-compatibility Plant species that can self-
fertilize (also termed simply ‘compatible’).
autogamy Self-fertilization.
auto-successionThe assemblage of a community
with no obvious environmental change or transition.
bauplan A particular body architectural plan.
benthic Living at, in, or associated with, struc-
tures on the bottom of a body of water.
biodiversity The variability of life from all
sources, including within species, between species,
and of ecosystems.
biodiversity hotspot May mean a geographic
area with high levels of species richness and/or
endemism. Also used to refer to areas that combine
high biodiversity with high threat to that biodiver-
sity (e.g. due to habitat loss).
biogeographical regions, kingdoms, and
provincesMajor biogeographical subdivisions of
the world based largely on shared composition at
the family level
biomassThe total weight of living tissue of organ-
isms accumulated over time, usually expressed as
dry weight of organic matter per unit area.342