36 Palmer, Instinctive Stillness in Birds. [jan' 



of course no danger of that experience being transmitted to future 

 generations, consequently stillness and protective mimicry as we 

 see them exhibited is a record of innumerable successes only. 

 Hence the habit once acquired in a very slight degree has, evidently 

 because of its invariable success, been transmitted in a slowly 

 intensifying degree and as a valuable attribute of nonpredatory 

 forms to the descendants as we know them. Mimicry we may say 

 is the result as well as the cause of the survival of the fittest, the 

 failures having been eliminated. 



Protective mimicry of the kind here considered, in combination 

 with stillness, is an epitome of weakness and, even in this sense, the 

 result as well as the cause. It is absolutely necessary for the pres- 

 ervation of many of the weaker and more defenceless species. 

 It illustrates dread, lack of combativeness and aggressiveness and 

 inability when exposed to danger to do much else of advantage. 

 Mimicking species are usually quite common and, as we often 

 speak of it, tame, and they propagate rapidly. On the other hand 

 their predatory enemies have also advanced in their mimetic 

 tendencies, usually aggressive. 



It may be noted here that the parents in many cases, especially 

 among ground species, successfully attract the attention of the 

 marauder by feigning lameness and then using their power of flight 

 to escape the deluded enemy. In perhaps all cases the warning cry 

 of the parent bird is sufficient to functionize the, until then, latent 

 mimetic propensity to stillness of its young. 



In nonpredatory birds in which no simulative mimicry is evident, 

 or very slight, the first law of preservation is unquestionably flight ; 

 they escape, or endeavor to do so, at the first indication of danger: 

 while in birds whose colors and habits are in any way simulative 

 and therefore entirely or largely protective, the first law of preserva- 

 tion is stillness even when there is great danger of being captured. 



The point that I have here endeavored to emphasize especially 

 is that protective resemblance (environmental mimicry), as to 

 color, markings and shadings, is of little value generally unless it is 

 conbined with one other feature, the dominant factor, stillness. 



