44 EDWARD A. WILSON. 
of the mountain in beaten tracks. One cannot but marvel at the persistence with 
which these little birds, using their feet, bills, and flippers, laboriously climb to the 
summit of such rugged slopes. Why, one wonders, should they ever set themselves 
such an infinite amount of unnecessary labour when there is ample room for them to 
nest and rear their young on the flat moraines below ? 
The observations made on this rookery at Cape Adare by the zoologists of the 
Southern Cross’ Expedition show that but two journeys could be made to the summit 
during the twenty-four hours ; and this is no isolated example, for on other rookeries 
there were nests to be found fully as high and even farther from the shore. 
To return now to the actual feeding of the chickens. They have a method 
which is altogether entertaining, a method which exemplifies in a direct and indisputable 
manner the far-reaching law of the survival of the fittest. One may stand in the noisy 
crowd of penguins at Cape Crozier and watch the law in being from its many-sided 
aspects ; the cruelty, the pathos, the humour, and yet the admirable perfection of the 
whole system being irresistibly brought home to the observer. 
The sooty-grey young ones in the third week of January were almost as big as 
their parents, and quite as active. Of these young birds there were literally thousands, 
and all were hungry, many very hungry. Moreover, each individual chicken acted 
upon the supposition that every old bird as it came up from the shore was full of 
shrimps. On this assumption the old bird had no choice but to run the gauntlet. 
Chased incontinently up and down the rookery by the importunate infants, the fond 
parent ran hither and thither with a keen eye open for the chicken it once had called 
its own (fig. 38, p. 52). Driven at last to bay, it could only turn to swear and silence 
its persecuting followers for the moment with a vicious peck, but the moment its 
search again commenced it would be caught up and followed and worried in precisely 
the same way by a fresh relay of young ones, all belonging to someone else. 
As we stood there and watched this race for food we were gradually possessed 
with the idea that the chicks looked upon each adult coming up full-bellied from the 
shore, as not a parent only, but a food supply. The parents were labouring under a 
totally different idea, and intended either to find their own infants and feed them, or 
else to assimilate their already partially digested catch themselves. The more robust 
of the young thus worried an adult until, because of his importunity, he was fed. But 
with the less robust a much more pathetic ending was the rule. A chick that had 
fallen behind in this literal race for life, starving and weak, and getting daily weaker 
because it could not run fast enough to insist on being fed, again and again ran off 
pursuing with the rest. Again and again it stumbled and fell, persistently whining 
out its hunger ina shrill and melancholy pipe, till at last the race was given up. 
Forced thus by sheer exhaustion to stop and rest, it had no chance of getting food. 
Each hurrying parent with its little following of hungry chicks, intent on one thing 
only, rushed quickly by, and the starveling dropped behind to gather strength for one 
more effort. Again it fails, a robuster bird has forced the pace, and again success is 
