BioConcepts

invasioninvasion (fr.); Invasion (ger.)

• 1) A harmful incursion of a disease. (OED 1989)
  category disease

  1665

  The fore-runners […] of the Cold fit of an Ague, the first Invasion of that Disease having been preceded by the like Distempers.

  Boyle, R. (1665). Occasional Reflections upon Several Subjects: Q6v.
  

• 2) The spreading of pathogenic microorganisms or malignant cells that are already in the body to new sites. (OED 1989)
  category disease

  1891

  Invasion […] the process by which a particular organ or part becomes affected with disease or parasites existing elsewhere in the organism.

  Foster, F.P. (1891). An Illustrated Encyclopaedic Medical Dictionary, vol. 3: 2011.
  

  1892

  The invasion of the blood which occurs in anthrax and in various forms of septicæmia in the lower animals, induced by subcutaneous inoculation with pure cultures of certain pathogenic bacteria, does not generally immediately follow the inoculation.

  Sternberg, G.M. (1892). A Manual of Bacteriology: 221.
  

• 3) The spread of a plant or animal population into an area formerly free of the species concerned. (OED 1989)
  category biogeography

  1839

  [A]n invasion on so grand a scale of one plant [Cynara cardunculus] over the aborigines.

  Darwin, C. (1839). Narrative of the Surveying Voyages of His Majesty’s Ships Adventure and Beagle between the years 1826 and 1836: 138.

  1853

  »l’invasion en Angleterre d’une espèce américaine, l’Anacharis Alsinastrum

  Anonymus (1853). [Rec. Marshall, W. (1852). The New Water Weed, Anacharis Alsinastrum]. Archives des sciences physiques et naturelles 24, 196-197: 196; cf. Anonymus (1853). Alarming invasion. Chambers’s Edinburgh Journal 19, 372-373.

  1855

  l’invasion moderne d’autres espèces en Italie

  de Candolle, A. (1855). Géographie botanique raisonnée, vol. 2: 626; cf. 680; 708; 722; 760; 1062; 1120.

  1864

  the invasion of territory

  Spencer, H. (1864). The Principles of Biology, vol. 1: 315.

  1882

  Pflanzen-Invasion

  Goeze, E. (1882). Pflanzengeographie für Gärtner und Freunde des Gartenbaues: 109.

  1905

  By invasion is understood the movement of plants from an area of a certain character into one of a different character, and their colonization in the latter.

  Clements, F.E. (1905). Research Methods in Ecology: 210.
  

  1958

  We have to accept the proposition that invasions of animals and plants and their parasites—and our parasites—will continue.

  Elton, C. (1958). Ecology of Invasions: 111.