Page:Creation by Evolution (1928).djvu/402

three examples; and even to-day the process is being very rapidly continued by man, who is, often needlessly, exterminating entire species—strange creatures like the great auk, lovely ones like the passenger pigeon or the sea-otter. Extinction is in itself not a good but an evil. It can only be a good on balance, if and when it is necessary that one group or type should perish that another more advanced group should flourish.

Then, as we have seen, specialization, though sometimes we should call it good, is never an unmixed or a balanced good. Not only that, but in some of the examples considered, such as parasitism, the balance is the other way, and what seems good to us is outweighed by what seems clearly evil. If tapeworms could reason and formulate their opinions about the universe, they would have to admit that the general trend of evolution was very different in its direction from that to which they owed their being, and that on the whole the two were opposed. They would, presumably, have to adopt that philosophy or belief which characterized the Manicheans of the early Christian era. Even the products of specialization that to us is clearly on balance good, though limited—such products, for instance, as the birds—would (if they were able to think it all out) think in rather different terms. Their specialization has led to flight, to intense activity, to colour and song unrivalled among the mammals. Well might they pity earthbound, drab-coloured, hairy creatures, and maintain that activity and the conquest of the air were the highest achievements of evolving life. But they would be wrong. It is simply a matter of hard fact, which takes no account of actual human wishes or hypothetical bird wishes, that for some reason (probably their sacrifice of fore-limb for a tool of flight) the birds' brain-development has been restricted, whereas the mammals,