Here is what students in Biology 221a at UWO get:
Parasitism is a relationship between two organisms, the larger of which
is physiologically dependent on the smaller; where the incidence and
prevalence of parasites in the host population is non-random; where the
reproductive potential is higher in the parasite; and where the parasite
has the potential to cause harm to the host.
I ripped this off from somewhere, can't remember where, but it is the
basis for an entire lecture on each aspect of the definition. The last
part of the definition may be relevant to previous discussion in this
list.
Mike Clarke
