| dc.description.abstract | Examples of mimicry among vertebrates are numerically fewer than examples involving insects. The relatively small number of species of vertebrates, compared with the number of species of insects, probably explains some of the apparent scarcity of mimicry. Possibly more important is a mismatch between the primarily visual sensory world of humans and the predominantly chemosensory, auditory, and tactile worlds of most other vertebrates, which has probably concealed many manifestations of mimicry. Systematic investigation of the information that vertebrates convey through these sensory modalities will probably reveal many additional examples of mimicry. Concrete homotypies-those cases in which the model can be identified as a particular species of animal-are widespread among fishes and amphibians and have been suggested for birds and mammals. Both Batesian and Mullerian protective mimicry systems have been described. Because vertebrates grow during their lifetimes without conspicuous changes in morphology, size limitation is manifested in some mimetic systems. Non-protective mimicry also occurs among vertebrates: mimicry of females is an alternative reproductive strategy for males, and many nest parasites mimic the eggs and young of their hosts. Abstract homotypies-cases in which the model cannot be identified as a particular species or group of species-are characteristic of mimicry of venomous snakes. Large body sizes, ontogenetic change in body size, and potentially lethal deterrents to attack by predators are the special characteristics of venomous snakes as models in mimicry systems. The risk for a dupe that mistakes a venomous snake for its mimic makes mimicry of venomous snakes a high-stakes game. The special characteristics of these mimicry systems (broad generalization of the characteristics of models, mimics that incorporate features of two or more models, and innate avoidance of models by predators) probably reflect that risk for a dupe. As such, these mimicry systems provide a new perspective on the mechanics of mimicry that may have parallels in some examples of mimicry of invertebrates. | en_US |
