Bio3520
Chapter 2
Natural Selection
selection
by human breeding programs can result in the evolution of certain traits in
animals
and
plants.
The process of
selection
operates on at least three factors: variation, fitness consequences, and heritability.
of a selectable
trait,
or phenotype, provides the raw material for natural selection to operate.
Differences
in
as a consequence of the phenotype variation result in variable selection.
Most behavioral traits are
inherited
through
and can be measured by
broad-sense
and
narrow-sense
heritability.
Natural selection on
traits such as
strategies
and
activities.
have been shown in
guppies.
Natural selection results in
- traits with the highest relative fitness in a given
environment;
but not all behaviors are
adaptive,
as shown in
parasitism of wood
ducks.
Genetic relatedness is often the
causation in
behavior as exhibited in naked mole
rats.
Genetic relatedness is also important in
, where one animal
aids
another individual against a third party.