Regional divergence in balanced polymorphism
Next, we tested for evidence of adaptive divergence of warning
coloration among populations for H. doris . For this, we tested
the prediction that divergence in red color morphs between Panama and
French Guiana H. doris populations resulted in greater predation
on non-native red morphs at each locality.
Of the two red morphs with differing hindwing rays corresponding to
Central America or South America, we expected predation rates to show
signs of differential avoidance based on frequency of a given signal in
each region. Specifically, we predicted that local phenotypes would be
significantly avoided relative to the exotic phenotypes. For this test
we used FT tests to detect differences in attacks on native, non-native
reds, and controls. In French Guiana, we found significant differences
in attacks on red morphs at coastal and inland sites. At coastal sites
we found significantly greater attacks on the non-native red morph than
native reds and controls, as would be expected since the local predators
would have been naive to this red warning wing pattern (n=560; p
< 0.0365; Figure 3). However, at the inland sites the
non-native morphs were not attacked significantly more than the
controls. Rather, we found that the native reds were attacked
significantly less at inland sites (n=584; p< 0.023; Figure
3). Interestingly, this finding fits the expectations of pFDS, as red
co-mimics are known to be at higher frequencies at inland than coastal
sites in French Guiana. In Panama, we found no evidence of differences
in attacks on native reds, non-native reds or controls.