Activity 



Adaptation 



SCIENTIFIC SIDE-LIGHTS 



8 



pended above it and hide it, as would hap- 

 pen to an aeronaut looking down from some 

 height above Vesuvius at the epoch of its 

 eruptions. FLAMMARION Popular Astron- 

 omy, bk. ii, ch. 7, p. 152. (A.) 



37. ACTOR PRACTISES ILLUSION 

 ON AUDIENCE /w Part upon Himself. 

 Among all varieties of this deception [of 

 self], that of the stage is the most com- 

 plete. The actor is a man who has elabo- 

 rately trained himself in the simulation of 

 certain feelings. And when his acting is of 

 the best quality, and the proper bodily atti- 

 tude, gesture, tone of voice, and so on, are hit 

 off, the force of the illusion completely mas- 

 ters us. For the moment we lose sight of the 

 theatrical surroundings, and see the actor as 

 really carried away by the passion which he 

 so closely imitates. Histrionic illusion is as 

 complete as any artistic variety can venture 

 to be. SULLY Illusions, ch. 9, p. 222. (A., 

 1897.) 



38. ACTS, AUTOMATIC, ACCOM- 

 PLISHING A PURPOSE The Decapitated 

 Frog Organism Constituted to Secure Its 

 Own Protection. It is well known that, if 

 the hind-foot of a frog that has had its head 

 cut off be pinched, it is withdrawn from the 

 irritation. The stimulus to the afferent 

 nerve reaches the gray matter of the spinal 

 cord, and sets free a force which excites to 

 action the corresponding motor nerves of 

 the same side. When the foot is pinched more 

 strongly, the force liberated by the stimulus 

 passes across the cord to the motor nerves 

 of the opposite side, and there is a simul- 

 taneous withdrawal of both limbs; and, if 

 the excitation be stronger still, there is a 

 wider irradiation of the effects of the stimu- 

 lus in the gray matter, and a movement of 

 all four limbs follows, the frog jumping 

 away. These movements of the decapitated 

 frog, which it is plain effect the definite pur- 

 pose of getting it out of the way of harm, 

 we believe to be analogous to the violent 

 coughing by which food that has gone the 

 wrong way is expelled from the human 

 larynx, or to the vomiting by which offend- 

 ing matter is ejected from the stomach. In- 

 dependently of consciousness and of will, an 

 organism plainly has the power call it in- 

 telligent or call it what we will of feeling 

 and eschewing what is hurtful to it, as well 

 as of feeling and ensuing what is beneficial 

 to it. MAUDSLEY Body and Mind, lect. 1, 

 p. 15. (A., 1898.) 



39. ADAPTABILITY AMONG ANI- 

 MALS Horse and Ox Follow Man Meet 

 Man's Enemies in Every Clime. This spec- 

 tacle [horses attacked by crocodiles] invol- 

 untarily reminds the contemplative observer 

 of the adaptability granted by an all-provi- 

 dent nature to certain animals and plants. 

 Like the farinaceous fruits of Ceres, the ox 

 and horse have followed man over the whole 

 surface of the earth from the Ganges to 

 the Rio de la Plata, and from the sea-coast 

 of Africa to the mountainous plain of 



Antisana, which lies higher than the Peak 

 of Teneriffe. In the one region the northern 

 birch, in the other the date-palm, protects 

 the wearied ox from the noonday sun. The 

 same species of animal which contends in 

 eastern Europe with bears and wolves is ex- 

 posed, in a different latitude, to the attacks 

 of tigers and crocodiles! HUMBOLDT Views 

 of Nature, p. 17. (Bell, 1896.) 



40. ADAPTABILITY OF BIRDS - Spar- 

 rows Utilize Electric Light. Some birds are 

 influenced by changes in their surroundings, 

 and alter their nesting habits when it 

 proves to their advantage to do so. Chim- 

 ney-swifts, who have exchanged hollow 

 trees, in which they were exposed to their 

 natural enemies, for the comparative safety 

 of chimneys, are good examples. But a 

 far better one is given by that prodigy in 

 feathers, the house-sparrow. Is there any 

 available site in which this thoroughly up- 

 to-date bird will not place its nest? It has 

 taken possession of even the hollow spaces 

 about certain kinds of electric lamps, and 

 has been observed repairing its nest at 

 night by their light! CHAPMAN Bird Life, 

 ch. 5, p. 68. (A., 1900.) 



41. ADAPTABILITY OF THE VERTE- 

 BRATE TYPE Laws of Nature the Expres- 

 sion of a Purpose. Among the many won- 

 ders of nature there is nothing more won- 

 derful than this the adaptability of the 

 one vertebrate type to the infinite variety 

 of life to which it serves as an organ and 

 a home. Its basement has been so laid that 

 every possible change or addition of super- 

 structure could be built upon it. Creatures 

 destined to live on the earth or in the 

 earth, on the sea or in the sea, under every 

 variety of condition of existence, have all 

 been made after that one pattern; and 

 each of them with as close an adaptation 

 to special function as if the pattern had 

 been designed for itself alone. It is true 

 that there are particular parts of it which 

 are of no use to particular animals. But 

 there is no part of it which is not of indis- 

 pensable use to some member of the group; 

 and there is one supreme form in which 

 all its elements receive their highest inter- 

 pretation and fulfilment. It is indeed won- 

 derful to think that the feeble and sprawl- 

 ing paddles on a newt, the ungainly flippers 

 of a seal, and the long leathery wings of a 

 bat, have all the same elements, bone for 

 bone, with that human hand which is the 

 supple instrument of man's contrivance, and 

 is alive even to the finger-tips, with the 

 power of expressing his intellect and his 

 will. Here again the laws of nature are 

 seen to be nothing but combinations of force 

 with a view to purpose : combinations which 

 indicate complete knowledge, not only of 

 what is, but of what is to be, and which 

 foresees the end from the beginning. 

 ARGYLL Reign of Law, ch. 4, p. 123. (Burt.) 



42. ADAPTATION ADMITTED Design 

 Denied Appearance of Purpose Assumed 



