Fig. 3. Calculated noise-scaled chromatic distances achieved by different hypothetical L cone tuning (see Materials and methods) for the visual task of discriminating target flowers from non-target flowers. In all illumination conditions, the L cone tuning of the honey possum is more advantageous than the L cone tunings of other marsupials (e.g. quokka), but better still would be L cone tunings more long-wave than those found in any other marsupials.