Fig. 2. Calculated signal-to-noise ratios achieved by different hypothetical L cone tuning (see Materials and methods) for the visual task of detecting flowers amongst their visual backgrounds (largely leaves and bark of vegetation). For both immediate and more general backgrounds the L cone tuning of the honey possum offers higher signal-to-noise ratios than the L cone tunings of other marsupials (e.g. quokka), but the best L cone would have a _max more long-wave than that found in any marsupials.