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Barnacles lack thumbs

Posted by Anekeia on 03 Feb 2016 at 15:41 GMT

Hitchhiking entails several requirements. First, a knowledge of occupying a place, and that there are other places to occupy. Second, the desire to occupy another place, or at least to vacate the one presently occupied. Third, knowledge of a means or mode of transport between such places. Fourth, knowledge of a way to exploit that means or mode of transportation. No one has demonstrated that barnacles have any of these characteristics, therefore they are not hitchhikers, literally, metaphorically or even by defensible analogy. A similar case can be made for "invading." Barnacles cannot hitchhike or invade, because they can neither intend nor carry out such complex, cooperative behavior, either as individuals or as species. Furthermore, as a consequence, they can "succeed" at neither. In summary, the teleological premises of this study are unsupportable, leaving its conclusions unsupported. While it is clear that the distribution of the species in question has broadened and the number of individuals extant at a given moment has almost doubtless increased, characterizing it as "successful invasion" via "hitchhiking" provides an anthropomorphic narrative, but not an explanation.

No competing interests declared.