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comparison, and it is on general grounds likely that a type that 

 began many millions of years ago may attain to greater perfection 

 than is shown by one of modern origin. No doubt an animal of 

 ancient origin may remain unprogressive if the conditions of its life 

 are unstimulating ; no doubt the higher animal starts on the should- 

 ers of its predecessors; but it seems good sense to expect, on the 

 whole, greater finish and harmony in races that have been subjected 

 for untold ages to severe winnowing. If we take imperfection to 

 mean lack of harmony in the internal working of the body, and 

 lack of fitness in reactions to the environment, what evidence is 

 there of this in the everyday life of animals? In a system where the 

 fit has always survived — fit even to dunghill conditions — can there 

 be much in the way of unfitness ? This is a question which has been 

 recentl}^ discussed by Prof. W. E. Ritter, in his interesting book. 



Fig. 192. 



Skull of Babirussa, showing the exaggerated growth of the tusks- 

 and lower canines. From a specimen. 



-the upper 



Animal and Human Conduct; and, taking a particular kind of mis- 

 adaptation, we wish to direct attention to some of his evidence that 

 animals often do themselves much injury. We do not believe it. 



During heavy rain in some American cities earthworms come to 

 the surface of the side-walks and are trampled on in thousands. 

 Various reasons have been given for this behaviour — e.g. that the 

 earthworms don't like to be drowned, but in any case the facts show 

 that an ancient type of action may persist in conditions where it is 

 disastrously inappropriate. But it does not seem to us to be a very 

 serious indictment of Nature's regime to say that the enregistration 

 and entailment of reactions that are usually profitable may lead to 

 fatality in such artificial circumstances as the city of Washington 

 affords. 



Vernon Kellogg gave some years ago a vivid description of the 

 terrific holocaust of mayflies around the arc-lamps at Lucerne. 

 These ephemeral insects have a sub-aquatic larval life of two or 

 three years, and an adult reproductive aerial life rarely exceeding 



