Re: What is the difference between an 'invasive' and an 'evasive' species?

Dear Jeff,

as a plant ecologist, I’ve learned a lot about invasive species over the years, but I’d never come across the phrase “evasive species” until I got your query. When I enter those words in google, though, I get upwards of 1400 hits. Many of them may have to do with a a Hawaiian band, but many others deal with “evasive species management” or “evasive species eradication.” From a quick, semi-random sampling of these latter articles, many seem to be free-association rants of dubious quality, or messages from homeowners’ associations. When I enter the words “evasive species” in scholarly search services (Biosis Previews, Web of Science, Google Scholar), the only papers that appear have to do with prey evasiveness (e.g., Iyer & Rao 1996, Hancox & Allen 1991).

I think this is a simple case of misuse of vocabulary. Since the two words are so similar, it’s easy to see how they could get confused, but the meanings are quite different. Invasive refers to something that has a tendency to spread and take over, while evasive refers to something that has a tendency to escape, hide, or avoid pursuit. “Evasive species,” though, is a neologism that deserves to be weeded out wherever it appears!

Saludos --Susan

Literature cited

Iyer, N. & T. Rao. 1996. Responses of the predatory rotifer Asplanchna intermedia to prey species differing in vulnerability: laboratory and field studies Freshwater Biology 36 (3) , 521–533.

Hancox, A.P. & J.A. Allen. 1991. A simulation of evasive mimicry in the wild. Journal of Zoology 223(1), 9-13.