entomophily Pollination by insects.
equilibrium A condition of balance between
opposing forces, such as between rates of immigra-
tion and extinction.
establishment The successful start or founding of
a population.
eustatic sea level changes Sea-level changes orig-
inated by the changing volume of water in the sea.
explosive radiation Evolutionary process result-
ing in an exceptional number of new monophyletic
species, e.g. the Hawaiian drosophilid flies or Lake
Malawi’s cichlid fishes.
extinction The loss of all populations of a species
from an island, or the global loss of a species.
extinction debt The anticipated eventual species
loss from an area of fragmented habitat following
fragmentation.
extirpation The loss of a local (insular) popula-
tion, not implying global loss of the species.
faunal drift The random sampling of species
reaching an ‘empty’ habitat, and thus providing a
novel (disharmonic) biotic environment in which
selection drives divergence into a variety of new
niches.
fitness The number of offspring an individual
produces over its lifetime.
founder effect Genetic loss that occurs when a
newly isolated population is founded, by a small
number of colonists.
founder event The colonization of an island by
the first representatives of a species.
frugivory Action of those animals feeding on fruits.
geitonogamy Pollen transfer occurring among
different flowers of the same individual.
gene flow The movement of alleles within a
population or between populations caused by the
dispersal of gametes or offspring.
generalist species A species that uses a relatively
large proportion, or in extreme cases all, of the
available resource types.
genetic drift Changes in gene frequency within a
population caused solely by chance without any
influence of natural selection.
Ghyben–Herzberg lens Rainwater accumulation
that floats on the denser salt or brackish water that
permeates the base of an island.
gigantism The tendency for some isolated
populations to undergo significant increases in
body size in comparison to their conspecifics on the
mainland.
Gondwanaland The southern super-continent,
which split apart from Pangaea (the last unique
land mass) some 160 Ma. It was composed of the
areas known today as South America, Africa,
Antarctica, Australia, India, Madagascar, New
Zealand, and New Caledonia.
guild A group of species exploiting the same class
of resources in a similar way.
guyot A type of seamount with a flat top,
formed by accretions of carbonate sediments on the
summit of a subsiding volcano.
habitat fragmentation Anthropogenic process by
which a large, continuous habitat is diminished in
area and divided into numerous isolated habitat
fragments.
habitat island Discrete patch of a particular
habitat type surrounded by a matrix of strongly
contrasting habitat(s).
halophytes Salt-tolerant plant species, commonly
found in salt marsh, drylands, and saline lake
environments.
hermaphrodites Individuals having both male
and female reproductive structures.
herpetofauna Amphibian and reptile fauna.
heterozygote An individual organism that pos-
sesses different alleles at a locus.
hybridization The production of offspring by
parents of two different species, populations, or
genotypes.
hyperdynamism An increase in the frequency
and/or amplitude of population, community, and
landscape dynamics in fragmented habitats.
hydrochory Dispersal by water.
Holocene The latest epoch, commencing about
11 500 years ago, at the end of the Pleistocene.
homozygote An individual organism that has the
same allele at each of its copies of a gene locus.
immigration In island ecology, refers to the
process of arrival of a propagule on an island not
occupied by that species (may be distinguished
from ‘supplementary immigration’—subsequent
reinforcements).GLOSSARY 345