July, 1929 



EVOLUTION 



Page Five 



into nerve cables that lead out to sense organs, to 

 lower brain centers, to the spinal-cord and the body 

 works. Through the white nerves the brain keeps in 

 touch with outside happenings, gets together its ideas 

 of what to do, and sends out its instructions to the 

 doing organs. 



It looks like a great apparatus, but how can that ap- 

 paratus think? Just watch. 



Build a strong, high, mesh-wire fence. Put a hen on 

 one side, chicken-feed on the other. The hen sees, 

 wants and acts — through eye, white optic-nerve, gray- 

 matter hook-up, white motor-nerve, the muscles that 

 act. But the hen hits the fence, fails. She tries again, 

 the same way, fails again. Her hen brain knows just 

 one way, her limit. So she does not eat. 



Put a dog on one side of the fence, dog-feed on 

 the other. The dog reacts like the hen, bumps into 

 the fence, fails the first time. It tries again, but in 

 difl^erent ways. For its gray-matter has several hook- 

 ups. It tries all ways, one after the other — jumping 

 over, digging under, breaking through, running around 

 the end. At last one way works. The dog eats. The 

 next time it does the right thing sooner. After several 

 times, does it first. The right gray-matter hook-up has 

 become habit. 



Now put a man on one side, his food on the other. 

 He sees, wants, and goes after it. He acts too, but not 

 with his body, not yet. He acts first in imagination. 

 One way after another. For his gray-matter also hooks 



up in several ways. One urges, "climb over," but an 

 idea stops the urge. "Too high." That idea just came 

 in over another hook-up from the eyes. A second cell 

 urges, "dig under," but another idea blocks it, "ground 

 too hard." Urges to break down, reach through, for- 

 get it, are all blocked by obstructing idea^ hook-ups, 

 and none go into action. But one urge, "go around 

 the end," is not blocked. Through eyes, white nerves, 

 gray-matter, comes the information that the fence 

 is short. That goes with the urge, not against it. So 

 the urge goes through, into action, with success. The 

 man eats. He gets results, quickly, easily, without 

 waste of physical action. 



Every nerve message tends to become (reflexly) a 

 nerve urge to act. The hen acted, one way only, was 

 stopped physically. The dog acted, several ways, was 

 stopped physically, except one way. The man acted 

 too, in several ways, but in gray-matter tryouts first. 

 His acts were stopped too, except one, but mentally, 

 not physically. His were stopped by gray-matter 

 "don'ts," by idea hook-ups that obstructed unpromis- 

 ing urges to action. We say he stopped to think. What 

 he did was to act out his urges mentally to see if they 

 would work. Only the workable urges went through 

 into physical action. That way he saved time and 

 effort. We call that adaptive thinking. Simple enough. 

 Just some gray-matter hook-ups. But they made man 

 master. He had more than the beasts. 



The next article will be just "Talk ! Talk ! ! Talk ! ! !" 



The Earliest Bird 



By FREDERIC A. LUCAS 



WHEN we come to the topic of the earliest bird — 

 not the one in the proverb — we are limited to the 

 famous Archaeopteryx from the Solenhofen quarries 

 of Germany, which at present forms the starting point 

 in the history of the feathered tribe. Birdlike, or at 

 least feathered, creatures must have existed before this, 

 as it is improbable that feathers and flight were ac- 

 quired at one bound, and so it may be that some of the 

 three-toed tracks in the Connecticut Valley were really 

 footprints of birds. Not birds as we know them, but 

 still creatures wearing feathers, these being the dis- 

 tinctive badge and livery of the order. No bird is with- 

 out them, no other creatures wear them, so the birds 

 may be exactly defined in just the two words, feathered 

 animals. The exclusive mark of birds is therefore not 

 flight but feathers, though in penguins, the feathers 

 have so changed that their identity is almost lost. 



By putting various facts together we obtain some 

 pretty good ideas regarding the appearance and habits 

 of the first birds. The immediate ancestors of birds, 

 their exact point of departure from other vertebrates, 

 are yet to be discovered ; at one time it was considered 

 that they were the direct descendants of Dinosaurs, 

 or that at least both were derived from the same parent 

 forms, and while that view was almost abandoned, it 



is again being brought forward with much to support 

 it. It has also been thought that birds and those flying 

 reptiles, the pterodactyls, have had a common ancestry, 

 and the possibility of this is still entertained. Be that 

 as it may, it is safe to consider that back in the past, 

 earlier than the Jurassic, were creatures neither bird 

 nor reptile, but possessing rudimentary feathers and 

 having the promise of a wing in the structure of their 

 forelegs, and some time one of these animals may 

 come to light; until then Archaeopteryx remains the 

 earliest known bird. 



In the Jurassic, then, when the Dinosaurs were the 

 lords of the earth and small mammals just beginning 

 to appear, we come upon traces of full-fledged birds. 

 The first intimation of their presence was the imprint 

 of a single feather found in that ancient treasure-house, 

 the Solenhofen quarries ; but as Hercules was revealed 

 by his foot, so the bird was made evident by the 

 feather whose discovery was announced August 15, 

 1861. And a little later, in September of the same 

 year, the bird itself turned up, and in 1877 a second 

 specimen was found, the two representing two species, 

 if not two distinct genera. These were very different 

 from any birds now living — so diflferent, indeed, and 

 bearing such evident traces of their reptilian ancestry, 

 (^Continued on Page 7) 



