February i6, 191 i] 



NATURE 



509 



We first have to examine the theory itself thoroughly, and 

 llvn draw the conclusions. 



Now, when Prof. Keith states that Klaatsch speaks 

 about a descent of man via the gorilla or via the orang, 

 this is wrong, as I hope to have made clear by the quota- 

 tions of Klaatsch *s paper. But when Prof. Keith speaks 

 about " convergence phenomena," to which has to be 

 ascribed a great deal, he no doubt touches the point most 

 exposed to criticism. It is, indeed, very difficult to believe 

 in two races, so much one like the other as man is to 

 man, and yet so unlike in some minute morphological 

 detail, as Aurignac is to Neanderthal, without supposing 

 that they once were very much more unlike, and that they 

 afterwards got more alike again by convergence. But this 

 difficulty of Klaatsch 's theory must never make us forget 

 the facts. The problem is this. There are two distinct 

 ** races " each possessing distinct morphological characters, 

 the one resembling the orang in these characters, the other 

 the gorilla. How can these differences and likenesses be 

 explained? It is certainly a very difficult problem, but a 

 verj- interesting one too, that is well worthy to receive 

 serious consideration. In any case, we must be grateful 

 to Klaatsch for having directed attention to this fact, and 

 for offering us an explanation — even if the latter should be 

 only a preliminary one. Gerh.\rdt v. Bonin. 



Breslau, January 28. 



While admiring the manner in which Herr Bonin 

 states the case for his Professor, I do not think he has 

 produced any evidence that requires me to alter my state- 

 ment that Prof. Klaatsch 's latest theory of the origin of 

 human races is founded on a " flimsy " basis. To under- 

 stand the nature of Prof. Klaatsch 's " pan-anthropoid " 

 theory of the origin of human races, it is necessary to 

 know the circumstances which led him to formulate it. 

 He found that the recently discovered Quaternary in- 

 dividual, which he has dignified with the name of Homo 

 aurignacensis hauseri — quite a modern type of man — 

 followed closely in point of time the individual he described 

 in 1908 as H. moustieriensis hauseri — a man of the 

 Neanderthal type. To account for the manner in which 

 these two quickly succeeding types differ, Prof. Klaatsch 

 propounded the " theon,- " that the Aurignac man is de- 

 scended from the orang stock, while the Neanderthal has 

 arisen in the gorilla line of descent. Now the characters 

 which separate those two types are exactly of the same 

 nature and of the same degree as separate a blood-horse 

 from a Shire stallion. Ever}' one of the points cited to 

 differentiate these two types of men are dependent on the 

 degree of muscular development. Bones, especially limb 

 bones, react sensitively to the muscles which move them ; 

 muscular impressions and processes for the insertion of 

 muscles vary from individual to individual, and from their 

 nature are most untrustworthy for the purpose of tracing 

 affinities. 



There is thus, in my opinion, no need to have recourse 

 to such a theory as Prof. Klaatsch has formulated to 

 explain the contrasted characters of the Aurignac and 

 Neanderthal types of men ; the problem is of the same 

 nature as meets us when we seek to explain contrasted 

 breeds among dogs and horses. Further, from a study of 

 acromegaly, that most interesting disease of growth which 

 I have had opportunities of examining of late, it is quite 

 aj^arent that an alteration in the action of the glands of 

 internal secretion — especially of the pituitary — will change 

 in the course of a few years a man of the Aurignac type 

 into one of the Neanderthal type — not an exact replica, but 



Bnear enough to leave no doubt that the characters of acro- 

 DMgalics and of Neanderthal men are of the same nature. 

 "~ Prof. Klaatsch also realised that if his theory were 

 applicable to two races of men, it should hold true for 

 all. Hence his suggestion that some may have arisen 

 from the chimpanzee and some from the gibbon. His 

 theory — a " pan-anthropoid " theory — of the origin of 

 human races is designed to account for the various features 

 which characterise and differentiate human races. 



To those acquainted with the great mass of evidence 

 which has accumulated in recent years relating to the 

 structure, development, and habits of living and extinct 

 anthropoids, Prof. Klaatsch 's theory must appear 

 alt<^ether untenable. From 1890 to 1900 I devoted myself 

 to an investigation of the Higher Primates, making com- 

 NO. 2155, VOL. 85] 



plete dissections of more than eighty animals, and 

 collected all descriptions which had been published at the 

 close of that period, with the intention of tracing, from 

 the mass of facts thus collected, the evolutionary history, 

 not only of man, but of each of the anthropoids. -\n 

 extensive analysis was made of the structural characters 

 of each of these animal forms. Characters are found in 

 them which also occur in lemurs, in South American 

 monkeys, in old-world monkeys. Some characters are 

 common to all the members of the Higher Primates 

 (man, gorilla, chimpanzee, orang, and gibbon) ; others 

 which are common to the Giant Primates (man, 

 gorilla, chimpanzee, and orang) ; others which are found 

 only in man, the gorilla, and chimpanzee ; and then a 

 considerable number which are peculiar to each member, 

 and may be regarded as late acquisitions. 



The characters I relied on were not such as Prof. 

 Klaatsch has used — the highly variable muscular impres- 

 sions on bones — they were points such as, I believe, most 

 anatomists would regard as of morphological worth. 

 Publication of my results was suspended owing to several 

 circumstances ; and I do not regret the fact, because since 

 then much additional evidence has been discovered, such 

 as the affinities shown by blood tests and by susceptibility 

 to disease, and much of an anatomical and physiological 

 nature, which I hope to gather and systematise. Mean- 

 time, I merely state briefly the results reached more than 

 ten years ago. Whatever theory is propounded of the 

 origin of the several members of the Higher Primates 

 must account for their structural and functional characters. 

 It is certain that Prof. Klaatsch 's theor>' is altogether 

 inapplicable for their explanation. 



Table giving an Analysis of the Structural Characters 

 of the Higher Primates. 



1065 1004 9S0 949 1C02 



The manner in which I seek to explain the distribution 

 of these characters is the following. The giblxKi is re- 

 garded as the representative of the basal stock of the 

 Higher Primates, and this Hjlobatian stock is looked 

 uport as an offshoot of a basal stock (late Eocene prob- 

 ably), which also gave rise to the Old and New World 

 monkeys. The distribution of characters of these groups 

 is thus explained in the modern representatives of the 

 Higher Primates. The evolution of the Hylobatian form 

 marks the first and most important stage in that process 

 which led to man's upright posture. The body of the 

 gibbon shows all the adaptations for an upright posture 

 (perhaps downright would be a better term) in which the 

 weight is more suspended from the arms than supported 

 by the legs. 



The next stage in the evolution of the Higher Primates 

 is clearly the appearance of a form which, compared to 

 all that had gone before, may be regarded as a " giant " 

 stock. There can be no doubt the Giant Primates (man, 

 gorilla, chimpanzee, and orang) arose from the Hylobatian 

 stock, and that Dryopithecus (a Miocene form) is a very 

 good example of an early Giant Primate. The first stage 

 in the evolution of the Higher Primates is the acquisition 

 of a new posture, the second the acquisition of a new 

 stature. The orang does not possess a number of 

 characters which are held in common by man, the gorilla, 

 and chimpanzee, and I therefore suppose that the orang 



