Parasitism

I hope no such planet exists, but consider one where slow, painful death from parasitism is universal. How would we talk about nature on such a planet? What kind of book would Thoreau have written there? ~ Arne Næss

In evolutionary biology, parasitism is a relationship between species, where one organism, the parasite, lives on or in another organism, the host, causing it some harm, and is adapted structurally to this way of life.

Arranged alphabetically by author or source:
A · B · C · D · E · F · G · H · I · J · K · L · M · N · O · P · Q · R · S · T · U · V · W · X · Y · Z · See also · External links

B

• All infections, of whatever type, with no exceptions, are products of parasitic beings; that is, by living organisms that enter in other living organisms, in which they find nourishment, that is, food that suits them, here they hatch, grow and reproduce themselves.
  • Agostino Bassi, quoted in Gasping for Air: How Breathing Is Killing Us and What We Can Do about It (2017) by Kevin Glynn
• [The parasite that causes malaria] edges through the cells of the stomach wall of the mosquito and forms a cyst which grows and eventually bursts to release hundreds of "sporozoites" into the body cavity of the mosquito [...] As far as we can tell, the parasite does not harm the mosquito [...] It has always seemed to me, though, that these growing cysts [...] must at least give the mosquito something corresponding to a stomach-ache.
  • Marston Bates, The Prevalence of People (1955), p. 165

D

• I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidæ with the express intention of their feeding within the living bodies of Caterpillars, or that a cat should play with mice.
  • Charles Darwin, "Letter to Asa Gray", 22 May 1860
• Fell Oestrus buries in her rapid course
  Her countless brood in stag, or bull, or horse;
  Whose hungry larva eats its living way,
  Hatch'd by the warmth, and issues into day.
  • Erasmus Darwin, The Temple of Nature, Canto IV (1803)
• The wing'd Ichneumon for her embryon young
  Gores with sharp horn the caterpillar throng.
  The cruel larva mines its silky course,
  And tears the vitals of its fostering nurse.
  • Erasmus Darwin, The Temple of Nature, Canto IV (1803)

E

• Whoever looks at the insect world, at flies, aphides, gnats and innumerable parasites, and even at the infant mammals, must have remarked the extreme content they take in suction, which constitutes the main business of their life. If we go into a library or newsroom, we see the same function on a higher plane, performed with like ardor, with equal impatience of interruption, indicating the sweetness of the act. In the highest civilization the book is still the highest delight.
  • Ralph Waldo Emerson, Letters and Social Aims (1875), p. 177

M

• Nearly all birds build nests of some kind in which to cradle their eggs and young. The cow-bird and cuckoo (European), however, are exceptions. These birds have the rather human practice of turning their cares and labours over to somebody else. They are loafers and parasites. They lay their eggs secretly in the nests of other birds, where their eggs are hatched and their young cared for by an alien mother. I have seen a mother song-sparrow hustling about among the shrubs and grasses for an hour at a time almost, gathering food for a young cow-bird nearly twice as big as she was, while her foundling sat phlegmatically at the foot of a tree chirping and fluttering its wings, and acting as a thankless and apparently bottomless receptacle for the morsel after morsel laboriously harvested for it by its tireless little foster-mother.
  • J. Howard Moore, The Universal Kinship (1906), pp. 172–173

N

• At least one distinguished ecologist, Ivar Mysterud, and a friend of the reindeer, thinks that even if there were an ecologically very innocent way of heavily reducing the population of a certain parasite that causes extreme pain to the reindeer, or of altering its habits, it should nevertheless not be carried out. The reason: it might disturb a relevant ecosystem. We know too little (the docta ignorantia of a field ecologist!). I agree that there is a presumption against it, but I disagree with his conclusion. The very prolonged, cruel sufferings of the reindeer count more. I am for radically reducing the population of the parasite even if it may be wrong according to L. If an ecosystem is dominated by pain-producing parasites, perhaps we might say its “beauty” diminishes? I am somewhat uncertain about how to interpret the term, and also about the possibility that human beings could preserve or enhance beauty by interfering.
  • Arne Næss, "Should We Try to Relieve Clear Cases of Suffering in Nature?", Pan Ecology, Vol. 6 (1991), p. 130
• I hope no such planet exists, but consider one where slow, painful death from parasitism is universal. How would we talk about nature on such a planet? What kind of book would Thoreau have written there?
  • Arne Næss, "Should We Try to Relieve Clear Cases of Suffering in Nature?", Pan Ecology, Vol. 6 (1991), p. 131
• The parasitology of mammals tells us about parasites that kill or maim in ways that elicit intense alarm, disgust, and great negative feelings in us. Evolution specialists tell us that such parasites are not among the most successful and highly developed ones, which thrive without inflicting intense suffering or death on their hosts.
  • Arne Næss, "Should We Try to Relieve Clear Cases of Suffering in Nature?", Pan Ecology, Vol. 6 (1991), p. 131
• And this is the ultimate lesson that our knowledge of the mode of transmission of typhus has taught us: Man carries on his skin a parasite, the louse. Civilization rids him of it. Should man regress, should he allow himself to resemble a primitive beast, the louse begins to multiply again and treats man as he deserves, as a brute beast. This conclusion would have endeared itself to the warm heart of Alfred Nobel. My contribution to it makes me feel less unworthy of the honour which you have conferred upon me in his name.
  • Charles Nicolle, "Investigations on Typhus", Nobel Lectures, Physiology or Medicine 1922–1941 (1965)

R

• I have failed in finding parasites in mosquitoes fed on malaria patients, but perhaps I am not using the proper kind of mosquito.
  • Ronald Ross, "Letter to his wife" (14 Aug 1897), Memoirs: With a Full Account of the Great Malaria Problem and its Solution (1923), p. 221

S

• After long pondering, I believe that I can define good and evil in terms to which even a biologist of the mechanical school can hardly take exception. At least, I fancy that I can do so for evil.
  The great evil of life is parasitism.
  • Alexander Skutch, "Life's Greatest Evil", The Scientific Monthly, Vol. 66, Iss. 6 (Jun. 1948), p. 514

T

• I can think of a few microorganisms, possibly the tubercle bacillus, the syphilis spirochete, the malarial parasite, and a few others, that have a selective advantage in their ability to infect human beings, but there is nothing to be gained, in an evolutionary sense, by the capacity to cause illness or death. Pathogenicity may be something of a disadvantage for most microbes.
  • Lewis Thomas, Lives of a Cell: Notes of a Biology Watcher (1978), pp. 73–74

W

• The insidious lethality of a parasitic wasp, the cruelty of a cat playing with a mouse – these are, after all, just the tip of the iceberg. To ponder natural selection is to be staggered by the amount of suffering and death that can be the price for a single, slight advance in organic design. And it is to realize, moreover, that the purpose of this "advance" – longer, sharper canine teeth in male chimpanzees, say – is often to make other animals suffer or die more surely. Organic design thrives on pain, and pain thrives on organic design.
  • Robert Wright, The Moral Animal: Why We Are the Way We Are (1994) ISBN 978-0679763994

See also

• Insect suffering
• Predation
• Wild animal suffering