Experimental studies of mimicry in some North American butterflies

Offered caged birds unpalatable model butterflies followed by palatable mimics, and separately offered mimics to birds with no prior experience of the model, recording whether birds rejected mimics they had never tasted.

Studied in

Danaus plexippus, Limenitis archippus, Aves

Sample size

caged birds offered models and mimics in sequence

Birds that had experienced the unpalatable model subsequently rejected the palatable mimic on sight, while birds without that experience ate it readily.

• Caged birds under laboratory conditions, with prey presented rather than found.
• The monarch–viceroy pairing itself was later reinterpreted, since viceroys proved to be unpalatable in their own right in at least some populations, which makes that particular pair Müllerian rather than Batesian.

• Warning coloration

  A warning colour is not a property of the animal wearing it. It works because predators learn, remember and generalise — and a signal nothing has learned about offers no protection at all.