I think the "relatively" may refer to evolutionary timescales, in which case - maybe. It would surprise me, though, especially given that psychoactive drug use

I think the "relatively" may refer to evolutionary timescales, in which case - maybe. It would surprise me, though, especially given that psychoactive drug use has been observed in the animal kingdom (source: wikipedia - what else?). Certainly on any shorter timescale, alcohol etc. use isn't even close to a new thing.