Parasites

I never quite understood how ‘parasitism’ qualified as a subcategory of symbiotic relationships.  “Mutualism’ seems only natural and logical as a type of symbiosis, that is, where both organisms benefit mutually from the relationship; for example, the wildebeest and the oxpecker – the wildebeest gets groomed of insects and the oxpecker bird gets fed.  I suppose ‘commensalism’ can fly under the radar of symbiosis while still being in its territory, that is where one organism benefits and the other is neither harmed nor benefitted; for example, the shark and the remora fish, where the remora fish gets scraps and the shark is left unaffected, though possibly pestered.  However, ‘parasitism’ seems to be an ironic subgroup of symbiosis, and one in which the players do not have equal roles and the scorecards look quite different at the end of the game…think ticks on dogs, cuckoo bird eggs in other birds’ nests, and head lice on heads owned by humans.  One relies on the other for its existence and propagation, without which it would perish; the other has its life, energy and resources sucked down a proverbial drain, and could hardly be nominally vested with title of ‘symbiosis’, except that that word, like an atom, has a positive, a negative and a neutral connotation.  All evil, like all parasites, may not be explicable, but all evil is like a parasite in at least on regard.  Its existence is contingent on something else, and in evil’s case that is goodness, and it is a perversion, distortion and twisting of such; it may not exist alone.  Like a parasite, evil preys and depends on a host.  Thankfully, however, it is also self-limiting in a way.  If one tick were able to suck all the blood from a dog in one setting, either it would burst from over-indulgence, or in an alternate dimension where surface tension physics is governed by a different set of constants, it would be full for quite some time but it would have depleted its available resources within any reasonable distance given that its buffet and long-distance locomotion were one in the same animal – quite literally.