THE DOGMA OF EVOLUTION 



support which is shown by the marvellous protective 

 colouring of animals, and of worms and insects, which 

 counterfeit leaves, twigs, or other organisms. But here 

 again, what is the advantage until the variation has 

 already proceeded so far in mimicry that the owner 

 can elude the keen eyes of its enemies'? 



As a last example consider for a moment the whole 

 subject of the weird, unaccountable habits of in- 

 sects. What knowledge we have is largely due to the 

 fascinating pages of Fabre, whom Darwin calls a 

 wonderful observer. Fabre was an unqualified and 

 bitter opponent of natural selection, and challenged 

 anyone to connect the wealth of habits and instincts 

 which he described with that doctrine. As an example, 

 we may cite the case of the wasp which paralyses 

 large insects with a single stab in a definite spot and 

 attaches an egg at another definite place. The insect in 

 this comatose state is devoured by the larva which be- 

 gins to eat at a certain point and continues in such a 

 direction that no vital nerve centre is severed until 

 the end of the meal. Fabre, by the most thorough and 

 delicate experiments, showed that the sting must be 

 inserted, the egg laid, and the larva work its way ex- 

 actly as invariably occurs. If there is the least devia- 

 tion in any of these three factors the paralysed insect 

 always dies and rots before the larva has finished its 

 meal and is ready to spin its cocoon, and the death of 

 the insect is the death of the larva. It is, as Fabre 

 says, impossible to explain this series of events by any 



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