Batesian Mimicry 
add that, even as natural selection is supposed to 
have been the cause of conspicuous colouring in 
some organisms, so has it caused others to assume 
intimidating attitudes or emit warning sounds, 
such as a hiss, when attacked. 
We now come to the third great class of 
animal colours—mimetic colours. Mimicry is 
of two kinds, known respectively as Batesian 
and Miillerian mimicry, after their respective 
discoverers. 
It has been found that some apparently 
warningly coloured butterflies and other creatures 
are palatable to insectivorous animals. The 
explanation given of this is that these showy but 
edible butterfles ‘‘ mimic,” that is to say, have the 
appearance of, show a general resemblance to, 
species which are unpalatable. This is known as 
Batesian mimicry. ‘“ Protective mimicry,” writes 
Professor Poulton (Zssays on Evolution, p. 361), 
‘“‘is here defined as an advantageous superficial 
resemblance of a palatable defenceless form to 
another that is specially defended so as to be 
disliked or feared by the majority of enemies 
of the groups to which both mimic and 
model belong—a resemblance which appeals 
to the senses of animal enemies . . . but 
does not extend to deep-seated characters, 
except when the superficial likeness is affected 
thereby.” 
As Wallace has pointed out, five conditions 
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