<Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> <P> Host--parasite coevolution is a special case of coevolution, which is defined as the reciprocal adaptive genetic change of two antagonists (e.g. different species or genes) through reciprocal selective pressures . In the particular case of host--parasite coevolution the antagonists are different species of host and parasite . </P> <P> Hosts and parasites exert reciprocal selective pressures on each other, which may lead to rapid reciprocal adaptation . For organisms with short generation times, host--parasite coevolution can be observed in comparatively small time periods, making it possible to study evolutionary change in real - time under both field and laboratory conditions . These interactions may thus serve as a counter-example to the common notion that evolution can only be detected across extended time . </P>

Can a parasite influence the evolution of its host