Continuity of Life 39 



An analogy from recent social history may make this 

 point clear. With the rapid improvement in automobiles 

 during the first quarter of the present century there were 

 produced many models which continued in production but 

 a short time. Many cars were used a comparatively short 

 time and replaced by their owners with supposedly better 

 models. There were thousands and thousands of cars that 

 were discarded while still usable. These gradually found 

 their way to less prosperous parts of the community and 

 many of them ended their existence in regions far removed 

 from the homes of their first owners. If we wanted to as- 

 semble a series of cars to show the progress of the art in the 

 hands of some of our first families, we could not get the needed 

 specimens in the back yards or outhouses of the respective 

 estates. We should have to hunt in remote rural and mountain 

 districts, in out-of-the-way places where alone the decrepit 

 cast-offs would be tolerated, and eventually in dumps and 

 scrap heaps far from the main traveled roads. This would 

 mean a zigzagging exploration, not only in space, but among 

 different social layers of our country. It is in pretty much 

 the same way that we must find representative specimens 

 for any continuous series of the ancestors of living plants 

 or animals. 



With every geological or climatic change the fauna and 

 flora of a given region changed. This does not necessarily 

 mean that all existing life forms were exterminated. It is 

 more likely that they merely migrated. In parts of New 

 England today are colonies of thriving Italians, but no signs 

 of Indians. This does not mean either that all Indians have 

 been exterminated, or that the Italians are descended from 

 the Indians who formerly occupied the same regions. The 

 horses that ran wild over the prairies of the middle west 

 during a part of the last century were not the direct descend- 

 ants of the animals whose fossils have been found in Kansas 

 and Nebraska. The descendants of those fossilized forms had 

 long ago become extinct, and the roaming horses were de- 

 scendants of immigrants from Europe within historic times. 



