Mullerian evolution

Another method for the evolution of Mullerian mimicry has been suggested. In a sense, a Batesian mimic is pre-adapted for evolution towards Mullerian mimicry. Furthermore, we have seen adjustments in the behavior of predators after being exposed to unpalatable prey They attack more slowly and cautiously, and sometimes taste but fail to maintain the attack (J. Brower, 1958,1960). Mimetic prey is thus not exposed to as severe attack as a non-mimic (until the sham is pierced). It would be more likely to survive and continue its evolution towards Mullerian mimicry if some incipient offensive distastefulness was developed (Huheey, 1961). It has been suggested that this is the only means available for the initiation of Mullerian mimicry in rare species (L. Brower et al., 1970). The conditions favoring the evolution of a Batesian mimic into a Mullerian mimic have been determined from the mathematical model and are not surprising The model must not be overly abundant nor have a strong protective deterrent. In other words, if the Batesian mimicry is weak, it behooves the mimic to evolve its own deterrent (Huheey, 1976). 

---

Traditionally, the concepts of Batesian and Mullerian mimicry have been considered completely distinct. Certainly, this seems true in many of the factors operating and in the predictions that one would make on the basis of Table 10.1. Therefore most students of mimicry have tended to view Batesian and Mullerian mimicry as discrete, isolated compartments. Some have gone so far as to say that mimicry is Batesian mimicry, that Mtillerian mimicry is merely warning coloration, and the two should not even be considered at the same time. As we shall see, this will not be the only time that semantics raises its head. Still, vexing questions continue to be posed. One is the very problem of the evolution of mimicry which, needs be, raises further questions concerning how species cross over the absolute boundaries of crypsis/aposematism or pseud-aposematism/aposematism (see Section 10.7). 

Despite the apparently discrete characters of Batesian and Mullerian mimicry, many authors (Fisher, 1958 Huheey, 1961 Linsley et al., 1961 Eisner et al., 1962 L. Brower and J. Brower, 1964 L. Brower et al., 1970 Pougheta/., 1973 Huheey, 1976 Brandon eta/., 1979 Sbordoni eta/., 1979) have discussed, from either an empirical or theoretical viewpoint, apparent intermediate cases between classical Batesian and Mullerian mimicry or the evolution of Batesian mimicry into Mullerian mimicry, or vice versa. 

Benson, W. W. (1977) On the supposed spectrum between Batesian and Mullerian mimicry. Evolution, 31, 454-5. 

Huheey, J. E. (1961) Studies in warning coloration and mimicry. III. Evolution of Mullerian mimicry. Evolution, 15, 567-8. 

Huheey, J. E. (1980c) Batesian and Mullerian mimicry Semantic and substantive differences of opinion. Evolution, 34, 1212-15. 

Turner, J. R. G. (1976a) Mullerian mimicry classical beanbag evolution and the role of ecological islands in adaptive race formation. In Population Genetics and Ecology (Karlin, S. and Nevo, E., eds) pp. 185-218. Academic Press, New York. 

---