... in their behaviour must have a genetic/nervous system origin. A good example of how behaviour can be genetic in origin and show that nervous systems can evolve to create different behavioural responses is found in deer. The white tailed deer odocoileus virginianus and the mule deer O. hemionus use different gaits when alarmed. The white deer gallop and the mule deer stott. This alone doesn't confer that the difference is due to their nervous systems but the genetic origin for the behaviour is inferred when a cross between the two species results in a hybrid that bounds when alarmed. In order to attain quantitative data the use of complex nervous systems, such as mammals, is unfeasible. A simpler nervous system is better suited and comparisons can then be extrapolated for the more complex animals. Within the invertebrates the model organism is, as ever, Drosophila. Since its genome has been sequenced ...

See this essay or coursework document in full right now