One definition of a "market" is people with the same needs who reference each other (i.e. talk to each other). This transmission of information ("word of mouth"

One definition of a "market" is people with the same needs who reference each other (i.e. talk to each other). This transmission of information ("word of mouth") is important for marketung [...though perhaps a bit different today, with referencing internet reviews.] Similarly, the definition of species as individuals that breed with each other has importance for transmission of genes. By this rationale, transitive gene transmission makes ring species a "species". A biologist told me that species are defined, not by theoretical interbreeding, but by actual breeding...so that a single species divided somehow in different environments, is now two species, even when no genetic change has occurred. By this strange extrinsic definition, the human races were different species before global travel... and now are one. And that SV hackers who only breed with other SV hackers, are a different species (and the rise in autistism incidence evidences a genetic effect - in a few million years, interbreeding will be impossible!). Similar for classes, the 1% etc.Though there is crossbreeding in practice, so at most these are ring species.