Darwin was one of the pioneering naturalists of the 19th century, mentioning invasive species in his writings. In The Origin of Species he described natives ‘conquered’ by introduced species (p. 69) and ‘yielding before advancing legions of plants and animals introduced from Europe’ (p. 164) and referred to ‘intruders’ (pp. 259, 314) having ‘invaded’ (p. 263) territories of other species.

Fifty years of invasion ecology : the legacy of Charles Elton / edited by David M. Richardson (2011)