“…35 Timby 2000, 244, 297, 307. 36 For discussion of similar issues, and how they might be modelled using meme theory, see Shennan 2002 andBiddulph 2012. This paper concentrates entirely on directly and indirectly biased transmission, assuming that the customers make choices on the basis of the availability and costs of the equipment, and possibly the emulation of higher-status individuals (Shennan 2002, 56-60), rather than expanding into the wider theoretical debate.…”