Hence it
will cause him no surprise that there should be geese and
frigate-birds with webbed feet, either living on the dry land or most
rarely alighting on the water; that there should be long-toed
corncrakes living in meadows instead of in swamps; that there should
be woodpeckers where not a tree grows; that there should be diving
thrushes, and petrels with the habits of auks.
ORGANS OF EXTREME PERFECTION AND COMPLICATION.
To suppose that the eye, with all its inimitable contrivances for
adjusting the focus to different distances, for admitting different
amounts of light, and for the correction of spherical and chromatic
aberration, could have been formed by natural selection, seems, I
freely confess, absurd in the highest possible degree. Yet reason
tells me, that if numerous gradations from a perfect and complex eye
to one very imperfect and simple, each grade being useful to its
possessor, can be shown to exist; if further, the eye does vary ever
so slightly, and the variations be inherited, which is certainly the
case; and if any variation or modification in the organ be ever useful
to an animal under changing conditions of life, then the difficulty of
believing that a perfect and complex eye could be formed by natural
selection, though insuperable by our imagination, can hardly be
considered real. How a nerve comes to be sensitive to light, hardly
concerns us more than how life itself first originated; but I may
remark that several facts make me suspect that any sensitive nerve may
be rendered sensitive to light, and likewise to those coarser
vibrations of the air which produce sound.
Pages:
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233