October 31, 19 12] 



NATURE 



>69 



the duration of the Pleistocene period was not more 

 than 139,000 years. 



The modern heterodox movement, which I have 

 sought to bring before you in the person of M. Rutot, 

 had as its pioneer the late Prof. Prestwich — a geo- 

 logist whose long experience and great knowledge 

 were tempered with a sound and conservative judg- 

 ment. In 1869 he found flints on the uplands of 

 Kent, between the Thames and the Weald, which 

 he recognised as certainly the handiwork of man. 

 Thousands of these eoliths have been collected by Mr. 

 Benjamin Harrison.^ The deposits in which these 

 eoliths are found were assigned by Prof. Prestwich 

 to a Pliocene date. Fifty years ago Sir Charles Lyell 

 expressed the opinion that "signs of man's existence" 

 would be found in the Cromer beds of East Anglia, 

 which mark the commencement of the Pleistocene 

 period in England. Eoliths have been found not 

 only in the Cromer beds, but also in the Pliocene 

 formations of that district — in the Norwich Crags by 

 Mr. Clarke, and under the Red Crag by my friend 

 Mr. Reid Moir. Thus in England heterodox opinion 

 traces man to the commencement of the Pliocene 

 period. I need only add that eoliths, as evidence of 

 man's existence, are rejected by many whose opinion 

 is entitled to our respect. The usually accepted 

 opinion, then, is that man makes his appear- 

 ance in a definitely human form about the com- 

 mencement of the Pleistocene period; there are also 

 those who refer his evolution to a much earlier 

 period of geological history. 



One thing is certain, whatever period is adopted, 

 the time must be long enough to allow mankind to 

 be distributed and differentiated as we now see it in 

 the world of to-day. Modern human races, white and 

 yellow, red, black or brown, although so different on 

 the surface, are yet so similar in their structure and 

 constitution that we must suppose all of them to have 

 arisen from a common stock. Let us look at the 

 problem in a concrete form. I will take as opposite 

 and contrasted types of modern humanity the fair- 

 haired, white-skinned, round-headed European, and 

 the woolly-haired, black-skinned negro jof Central 

 Africa, and set them side by side and study them 

 from a purely zoological point of view. We must 

 admit that both are highly specialised types ; neither 

 represents the ancestral form. Now, in seeking for 

 the ancestral form of our breeds of dogs, of horses, or 

 of cattle, we select one of a generalised and ancient 

 type — such as we conceive might have been modified 

 to produce modern breeds. We must apply the same 

 system to human races. If we search the present 

 world for the type of man who is most likely to serve 

 as a common ancestor for both negro and European 

 we find the nearest approach to the object of our 

 search in the aboriginal Australian. He is an ancient 

 and generalised tvne of humanitv ; he is not the direct 

 ancestor of either negro or European, but he has 

 apparently retained to a greater degree than any other 

 living race the characters of that common stock from 

 which both European and negro arose. 



If, then, we accept the Australian native as the 

 nearest apnroach to the common ancestor of 

 modern mankind — and it must be admitted 

 that it is not a low form of man we are 

 postulating as a common ancestor — can we 

 form any conception of the length of time which 

 would be required to produce the African and the 

 European from this common stock? What do we 

 know of the rate at which mankind evolves? There 

 is the classical instance of Egvnt. During his resi- 

 dence in that countrv Prof. Elliot Smith and his 

 colleagues— Dr. Wood Jones and Dr. Derry — had 



" Atr. Harrison has Informed the lecturer he first found those primitive 



NO. 2244, VOL. go] 



opportunities of examining the remains of Egyptians 

 belonging to every period — from pre-dynastic times 

 to the present day. They had thus facilities for 

 studying the evolution of a people over a period of 

 at least 6000 years — probably longer. They found 

 evidence of an infiltration of foreign blood both from 

 the north and from the south ; they noted minor 

 alterations in the configuration of the head and in 

 the state of the teeth and jaws, but they could not 

 say that the men at the end of that period were in 

 any respect a higher or more specialised tvpe than 

 the inhabitants of the Nile Vallev at the beginning 

 of that period. 



There is no need to go beyond our own country 

 to find evidence that the evolution of man proceeds at 

 a slow rate. We have now material enough to form 

 a fairly accurate conception of the physical condition 

 of the people who lived in Britain these 4000 years 

 past. Were the prehistoric Britons to come amongst 

 us now, dressed in our modern garb, they would pass 

 unnoticed as fellow-citizens. The Neolithic men of 

 France, Switzerland, and Germany were not in any 

 wise a lower race than their successors of to-day. 

 When we pass to examine human remains belonging 

 to more remote periods, we are confirmed in our 

 belief that the evolution of human races is a slow 

 process. In this country there have been found at 

 Galley Hill, at Bury St. Edmunds, and at Ipswich 

 human remains which belong at least to the middle 

 part of the Pleistocene period. These remains indi- 

 cate a kind of man somewhat different from our- 

 selves, but yet of the same type. In size of brain 

 and in complete adaptation to an upright posture, 

 they cannot be described as less highly evolved than 

 we are. 



Such evidence as we have, then, leads us to believe 

 that the evolution of a new and distinct variety of 

 mankind requires an extremelv long period of time. 



If we again ask : How long will it take to evolve 

 the African, on the one hand, and the European, on 

 the other, from a common stock? — Australoid, we 

 suppose, in form — it is very apparent, on our present 

 knowledge, we must make a very considerable allow- 

 ance of time. My own opinion is that the whole 

 length of the Pleistocene — a period, we shall say. of 

 400,000 years — is not more than sufficient. I am thus 

 postulating, in order to explain the differentiation and 

 distribution of modern races, that mankind, at the 

 beginning of the Pleistocene period, had reached a 

 phvsical condition which has its best modern repre- 

 sentation in the aborigines of Australia. 



Is it not possible, however, that the evolution of 

 man's bodv may not be a story of slow, continuous, 

 almost imperceptible change, but one of alternate 

 spurt and quiescence? The human bodv is notori- 

 ouslv the subject of sport, of defects, and malform?- 

 tions. Manv of vou will recall the book which Prof. 

 Bateson published eighteen years ago entitled 

 "Material for the Studv of Variation." The work 

 contained many facts which seemed to indicate that 

 the animal bodv was subject to violent structural 

 changes, and that a new form of being might be 

 produced almost at a bound. We often see men in 

 whom there is an extra vertebra in the loins, an addi- 

 tional rib, or a supernumerary digit, but we now 

 recognise that these marked structural changes are 

 merelv the extreme manifestations of a normal degree 

 of variation of which every man's body is the subject. 

 The bodies of men and anthropoids are notoriouslv 

 liable to anatomical variation, and we are justified 

 for that reason in regarding their bodies as particu- 

 larlv plastic material in the hands of evolution. When, 

 however, we come to examine the anatomical differ- 

 ences which separate one race of men from another, 

 we see that racial characters comprise, not those 



