Clearly in this case the knowledge of the hyberna-ting den is
not merely traditional--that is, handed down from generation to
generation, through the young each year following the adults, and so
forming the habit of repairing at certain seasons to a certain place;
for the young serpent soon abandons its parent to lead an independent
life; and on the approach of cold weather the hybernating den may be a
long distance away, ten or twenty, or even thirty miles from the spot in
which it was born. The annual return to the hybernating den is then a
fixed unalterable instinct, like the autumnal migration of some birds to
a warmer latitude. It is doubtless favourable to the serpents to
hybernate in large numbers massed together; and the habit of resorting
annually to the same spot once formed, we can imagine that the
individuals--perhaps a single couple in the first place--frequenting
some very deep, dry, and well-sheltered cavern, safe from enemies, would
have a great advantage over others of their race; that they would be
stronger and increase more, and spread during the summer months further
and further from the cavern on all sides; and that the further afield
they went the more would the instinct be perfected; since all the young
serpents that did not have the instinct of returning unerringly to the
ancestral refuge, and that, like the outsiders of their race, to put it
in that way, merely crept into the first hole they found on the approach
of the cold season, would be more liable to destruction.
Pages:
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320