The selective breeding by humans towards a desired trait in a plant,
animal, or other organism which is of value (usually economic) to the humans.
The process operates on the same principles as natural
selection.
A situation in which the best parents in a generation are chosen for
breeding on the basis of their progeny’s performance.
balancing selection
Definition:
A process of natural
selection where heterozygous
individuals are more adaptive, and thus selected for more often, than either
of the two types of homozygous
individuals.
A type of natural
selection which acts upon individual genes
and alleles within
an organism's genome.
Genic selection occurs whenever a gene or allele reproduces at a rate different
from the organism which carries it, for example if an allele is transmitted
to more than 50% of the gametes
of a heterozygous
individual (called "segregation distortion" or "meiotic drive").
A type of natural
selection which acts upon individual organisms
within a population.
An individual organism which has a particular beneficial characteristic
is better able to survive and reproduce than other individuals (which don't
have this beneficial characteristic). Individual selection is the most
common type of natural selection.
insertion sequence selection
Definition:
The selection of cells
within a population which have had a foreign piece of DNA
-- an insertion sequence
-- incorporated into their genomes.
interdemic selection
Definition:
A type of natural
selection which acts upon populations
within a species.
Interdemic selection occurs when populations die out or give rise to new
populations at different rates, depending on whether they have traits that
are beneficial or harmful to the population as a whole. It is also possible
for a trait to be harmful to the individuals within the population which
have it, but be beneficial to the population as a whole; such a trait would
thus be selected for until every individual within the population has the
trait (that is, the trait becomes fixed).
k selection
Definition:
In evolution,
the selection of
traits that aid an organism's competitive capability when the population
is at or near its carrying capacity.
The use of markers
to follow the inheritance of genes,
particularly those genes which cannot be readily identified. Selection
of a marker flanking a gene of interest, allows selection for the presence
(or absence) of a gene in a new progeny.
Placing organisms under conditions where the growth of those with a
particular genotype
will be favored.
species selection
Definition:
A type of natural
selection which acts upon species
within higher taxonomic
groups. Species selection occurs when speciation
and extinction
rates are affected by whether the species has a particular characteristic,
such that the number of species within a higher taxon which have the characteristic
might change depending on how beneficial or harmful it is to a species.
END
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