EVOLUTION OF INSTINCTIVE BEHAVIOUR 113 
congenital variation, we do not know. The intelligence 
which is said to have enabled the martin of the past to adopt 
this method of nidification is still operative. The nestlings 
brought up under the eaves would have opportunities for 
acquiring experience which might lead them to build under 
similar circumstances. Nest and eaves would be associated in 
the conscious situation. Nor would the effects of natural 
selection be necessarily excluded. One may suppose that in 
the open country, far from rock-shelters, those martins in 
which there was a congenital tendency to build in house- 
shelters would bring up their broods and transmit this 
tendency ; while those in which it was absent would either go 
elsewhere or fail to bring up broods at all. In the absence 
of fuller knowledge as to the truly instinctive nature of the 
behaviour, and as to its mode of genesis, we are in large 
degree at the mercy of conjecture. But in any case the in- 
cidence of elimination is not necessarily excluded, and there 
are, therefore, no grounds for denying that natural selection 
has been a co-operating factor in the evolution of the instinc- 
tive behaviour, if such it be. 
It is well known that the lapwing will apparently simulate 
the actions of a wounded bird, with the object, as it seems, of 
drawing intruders away from her nest. And such tactics are 
not restricted to this bird, nor even to one or two species. 
They are common, no doubt with diversities of detail, to such 
different birds as grouse, pigeons, plovers, rails, avocets, ducks, 
pipits, buntings, and warblers. Granting that the behaviour 
is truly instinctive, it forms a very pretty subject for trans- 
missionists and their critics to quarrel over. “If we seek, as 
an-example,” the transmissionist may exclaim, “an instinct 
which bears the marks of its intelligent, and therefore acquired 
origin, this of feigning wounded provides all that we can 
possibly demand.” “What mode of instinctive behaviour,” the 
selectionist may ask, ‘can be adduced which is more obviously 
useful to the species? Is not this just the kind of procedure 
which natural selection, if it be a factor at all, must fix upon 
and perpetuate through the elimination of failures? Those 
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