PALEONTOLOGY 



337 



progression from a distinctly ape-Uke animal to a decidedly man-like 

 being. 



Unfortunately there is no evidence that these several forms belong to 

 a genetically- continuous series. They may be related as ancestor and 

 descendant, but that they are so can be stated only as a conjecture. 

 Still more unfortunate is it that Cro-Magnon man appears not to have 

 given rise to the highly developed races of today. The Cro-Magnon race 

 declined being probably represented by few individuals today, and was 

 superseded by immigrants from the east. How the human development 

 proceeded in Asia, if that is where the early development of the races that 

 overran Europe took place, can only be told when fossils of early men 

 are discovered in that continent. Perhaps such discoveries, if they are 



Fig. 232. — Restorations of prehistoric men. Left, Pithecanthropus erectus; middle, 

 Homo neanderihalenais, modeled "on the Chapelle-aux-Saints skull; right, Cro-Magnon man, 

 modeled on type skull of the race. (From original busts by Professor J. H. McGregor.) 



ever made, will make it possible to connect the ancestry of present-day 

 man with some meml^cr of the series described above earlier than the 

 Cro-Magnon race. 



The Natixre of Paleontological Evidence.^ — Fossils, as even the brief 

 account in this chapter will show, constitute some of the very best evi- 

 dence regarding the fact of evolution. In this respect, paleontology 

 differs from most other sources of information concerning evolution in 

 the distant past. When the study of comparative anatomy reveals 

 likenesses in different animals, one can only infer that these likenevsscs 

 are due to inheritance from a common ancestry. When comparative 

 embryology shows similarities in the embryos of two groups of animals, 



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