•2 experimental approaches that are useful to biologist in evaluating how
genes and experience interact to shape behaviours:
1.In a deprivation experiment, investigators rear a young animal so that
it is deprived of all experience relevant to the behaviour under study. If it
still exhibits the behaviour, may assume that the behaviour can develop
without opportunities to learn it.
2.In genetic experiments, investigators alter the genomes of organisms
by interbreeding closely related species, by comparing individuals that
differ in only 1 or a few genes or by knocking out or inserting specific
genes to determine how these manipulations affect their behaviour.
Deprivation experiments: E.g. tree squirrel. Experiment showed that hereditary
underlies the food-storing behaviours of the tree squirrel species, but the behaviour
was expressed only when the environment provided conditions that stimulated the
behaviour (the presence of a nut).
Selective Breeding: Is a means of genetic manipulation that has been in use since
plants and animals were 1st domesticated. It has been used extensively to select for
both anatomical traits and behaviour.
Interbreeding: E.g. interbreeding of duck species by Konrad Lorenz. When Lorenz
crossbred duck species the hybrid offspring expressed some elements of each
parent’s courtship display, but in new combination. He also observed that the
hybrids sometimes exhibited display elements that were not in the repertoire of
either parent species, but were characteristic of other species. His hybridization
studies clearly demonstrated that the stereotypic motor patterns f the courtship
displays are inherited. The observation that females are not interested in males
performing hybrid displays is evidence that sexual selection has shaped these
genetically determined behaviours.
Gene knockout experiments: E.g. experiments with house mice. Female mice in
which the fos gene is active gather their pups together, keep them warm and