THE ANIMAL CLIMAX-THE CHORDATES 



355 



achieved from their habit of brachiating, 

 and became the terrestrial forms, including 

 man, of today. However, there is a great 

 deal of doubt by most paleontologists on 

 this matter at the present time. 



Fossil remains of early man have been 

 few and only fragmentary to date, a 

 fact which makes the reconstruction of 

 man's evolution a very difficult one. How- 

 ever, certain important discoveries have 

 been made which give some clue as to his 

 origin. The most primitive skull of a man- 

 ape is that found in South Africa, called 

 Australopithecus, the "southern ape." The 

 several skeletons or parts of skeletons that 

 have been found were in Pleistocene de- 

 posits, the period in which man made his 

 long slow evolution to present-day types. 

 This fossil ape skull shows characteristics 

 of both the great apes of today and of man, 

 which is what would be expected in a "miss- 

 ing link." Its brain case has a capacity of 

 over 700 cc, which exceeds that of the larg- 

 est gorillas today, but is still a long way 

 from that of the next higher fossil man, 

 Pithecanthropus, with a capacity of about 

 900 cc. Its teeth and brain development 

 certainly could have belonged to a form 

 that was heading toward modern man. 



Pithecanthropus has stirred up more con- 

 troversy since its discovery than any other 

 fossil man. This is understandable since its 

 discoverer, Eugene Dubois, a Dutch Army 

 officer, set out to find the missing link be- 

 tween man and the apes, probably because 

 of the intense controversy that had been 

 stirred up by Darwin's Descent of Man, 

 which was at the time in the minds of 

 everyone. It is most remarkable that a man 

 should set out to accomplish such a diffi- 

 cult task and actually carry out his promise. 

 Otliers searched furiously for the next few 

 years, but it was not until 1936 that other 

 similar skeletons were discovered. The orig- 

 inal material, which consisted of a skull 

 cap, three teeth, and a femur bone, was 

 discovered in the banks of the Solo River 

 in Java in 1892. Dubois called these finds 



Pithecanthropus erectus, the "erect man" 

 (Fig. 13-74). His claim was that this was 

 an intermediate form, half ape, half man, 

 which may well have been the case, be- 

 cause other skeletons tend to bear out these 

 assumptions. The man had a very low brow 

 and the size of his brain case was about 900 

 cc, a much greater capacity than that of 

 the great apes though smaller than any 

 modern man ( average about 1500 cc. ) . The 

 tooth pattern is definitely human, and it is 

 interesting to note that the wisdom teeth 

 show no signs of disappearing as is com- 

 mon in modern man. He probably lived in 

 the neighborhood of 500,000 years ago. 



A close relative of Pitheca7ithropus is 

 Sinanthropus, commonly known as the Pe- 

 king man because the remains were found 

 in a cave some 30 miles from Peking, China. 

 These middle Pleistocene deposits stimu- 

 lated Dr. Davidson Black in the 1920's to 

 investigate them for the possibility of hu- 

 man remains. He found first only a tooth 

 here, but during the next decade over 30 

 individuals were unearthed, so that the 

 evidence is very complete concerning this 

 primitive man. In most respects, Sinanthro- 

 pus is very similar to Pithecanthropus, ex- 

 cept for the fact tliat the brain case is 

 somewhat larger on the average (915-1200 

 cc. ) . The lower jaw still maintains a gap for 

 the fitting of the upper canines, a definite 

 simian character. The leg bones indicate an 

 upright posture. He apparently had a cul- 

 ture which was far above anything the apes 

 would be likely to have. He used fire and 

 made stone tools. There is evidence, accord- 

 ing to Romer, that he was cannibalistic, 

 based on the fact that so many skulls are 

 present in the deposits, each one crushed 

 at the base. This might mean that the 

 bodies were eaten and the brain removed 

 for the same purpose, a horrible but prob- 

 ably not uncommon custom for early man. 



The Neanderthal man was the first fossil 

 man discovered ( 1856 ) and many of his 

 remains since have been uncovered, indi- 

 cating that he roamed over parts of Asia, 



