242 



♦ KNOWLEDGE ♦ 



[Seit. 



PROFESSOR BOYD DAWKIXS ON 

 RIVER DRIFT MAN. 



'P HE follow! 

 L address ' 



ling IS an al>stract of Professor Boyd Dawkius's 

 to tlie department of Anthropology, or at 

 least of that portion of it which relates to our Pleistocene 

 ancestor, River Driu Man — a term not meaning, Viy-the- 

 way, as many (we liiul) imagine, a being who passed the 

 principal part of his tiuio in drifting about rivers, but man 

 in that stage of human development whereof the chief 

 evidence we have is found in river drift 



Tlie characteristics of the evolution of living forms may 

 lie summe<l up as follows : — 



I. Eocene — in which the j lacontal mammals now on 

 earth were represented by allied forms belonging to 

 existing orders and families. Li\ing orders and families 

 appear ; lemurs {IcmuriJir) in Europe and North America. 

 Evidence found in fresh-water and marine strata; 

 lignites. 



II. Miocene — in which the alliance between living and 

 placental mammals is more close than before. Living 

 genera appear; apes (gimiada) in Europe and North 

 America. E\-idence — fresh-water and marine strata ; 

 volcanic dihris (Auvergne) ; lignites. 



III. Pliocene — in which living species of placental 

 mammals appear. Living species appear ; apes, gimiadte, 

 in Southern Europe. Evidence found in fresh-water and 

 marine .-.trata ; volcanic debris (Auvergne). 



IV. Pleistocene — in which living species of placental 

 mammals are more abundant than the extinct Man 

 appears ; antlirojiidn . the paheolithic hunter ; living species 

 abundant Evidence — refuse-heaps, contents of caves, 

 river deposits, sub-marine forests, boulder clay, moraines, 

 marine sands, and shingla 



V. — Prehistoric— in which domestic animals and culti- 

 vated fruits appear. Man abundant, domestic animals, 

 cultivated fruits, spinning, weaving, pottery making, 

 mining, commerce; the neolithic, bronze, "and iron 

 stages of culture. Evidence — camps, habitations, tombs, 

 refuse-heaps, surface accumulation, caves, alluvia, peat 

 l>ogs, submarine forests, raised beaches. 



VI. Historic — in which the events are recorded in 

 history. Evidence — documents, refuse heaps, caves, 

 tombs. 



The orders, families, genera, and species in the above 

 summary, when traced forward in time, fall into the shape 

 of a genealogical tree, with its trunk hidden in tlie 

 secondary period, and its branchleta (the living species) 

 passing upwards from the Pliocene, a tree of life, with 

 living mammalia for its fruits and foliage. Were the ex- 

 tinct species taken into account, it would be seen that th(!y 

 fill up the intervals separating one living fonii from another, 

 and that they too grow more and more like the living forms 

 as they approach nearer t(> the present day. It must be 

 rememl^red that in the alx)ve definitions the fossil marsu- 

 pials arc purposely ignored, because they began their 

 specialization in the secondary p«;rio<l, and had arrived in 

 the Eocene at the stage which is marked by the presence 

 of a living genus— the opossum (DvUlphyH). 



It will U^ Mt<-n that our inquiry into the antiquity of 

 man is limiU-d to the last four of the divisions. The most 

 specialis*^ of all animals cannot Ije looked for until the 

 higher mammalia by which he is now surrounded were 

 alive. We cannot imagine him in the Eocene age, at a 

 time when animal life was not sudiciently diflerentiated 

 to pr.««!nt us with any living genera of placental mammals. 

 Nor is there any prol^ability of his having appeared on the 

 earth in the Miocene, because of the absence of higher 



placental mammals belonging to living species. It is most 

 unlikely that man should have belonged to a fauna in 

 which no other living species of mammal was present He 

 belongs to a more advanced stage of evolution than the 

 mid-Miocene of Thenay. I'p to this time the evolution of 

 the animal kingdom had advanced no further than the 

 Siminda- in the direition of man|; and the apes then haunt- 

 ing the forests of Italy, France, and CJermany represent 

 the highest type of those on the earth. 



We may also look at the tjuestion from another point of 

 view. If man were upon the earth in the Miocene age, it 

 is incredible that he should not have become something 

 else in the long lapse of ages, and during the changes in the 

 conditions of life, by which all the Miocene land mammalia 

 have been so profoundly atl'ected, that they have been 

 either exterminated, or have assumed new forms. Nor 

 in the succeeding Pliocene age can wo expect to find man 

 upon the earth, because of the very few living species^ 

 of placental mammals then alive. It is not until we 

 arrive at the succeeding stage, or the Pleistocene, 

 when living species of mammalia begin to abound,, 

 that we meet with indisputable traces of the pre- 

 sence of man on the earth.* The rudely chipped im- 

 plements of the River-drift hunter lie scattered througli 

 the late Pleistocene river deposits in Southern and Eastern 

 England in enormous abundance, and as a rule in associa- 

 tion with the remains of animals of Arctic and of warm 

 habit, as well as some or other of the extinct species of 

 reindeer and hippopotamus along with mammoth and woolly 

 rhinoceros. 



The geographical change in Northern Europe at th') close 

 of the I""orest-bed age was ^ery great The forest of the 

 North Sea sank beneath the waves, and Britain was de- 

 pressed to a depth of no less than 2,300 ft in the Welsh 

 mountains, and was reduced to an archipelago of islands, 

 composed of what are now the higher lands. The area of the 

 Englisli Channel also was depressed, and the " silver streak" 

 was wider than it is now, as is proved by the raised beach 

 at Brighton, at Bracklesham, and elsewhere, which marks 

 the sea-line of the largest island of the Archipelago, the 

 Southern Island, as it may be termed, the northern shores 

 of which extended along a line passing from Bristol to 

 London. The northern shore of the Continent at this time 

 extended eastwards from Abl)eville, north of the Erzgebirge, 

 through Saxony and Poland, into the middle of Russia, 

 Scandinavia Ijeing an island from which the glaciers 

 descended into the sea. This geographical change was 

 accompanied by a corresponding change in climate. 

 Glaciers descended from tlu; higher mountains to the sea 

 level, and icebergs, melting as they passed southwards, 

 deposited thcar burdens of clay, sand, and erratics, which 

 occupy such a wide area in the portions tluai submerged of 

 Britain and the Continent. This depression was followed 

 l>y a re-elevation, Ijy which the British Isles, a part of the 

 Continent, and all the large tract of country within the 

 100-fathom line, again V^ecamc the feeding-grounds of the 

 late Pleistocene mammalia. 



An appeal to the animals associated with the River-drift 

 implements will not help us to lix the exact relation of 

 man to these changes, because they were in Britain before 

 as well as after the submergence, and were living through- 

 out in those parts of Europe which were not submerged. 

 It can only be done in areas where the submergence is 

 clearly defined. At Salisbury, for instance, the River- 



• Tliu I'loiBtocpnc period is the e(|uivalciit of the Qimlomttry ol' 

 tlio French, and tlio I'oHtiiliocene of tho olilcr workR of Lyell, and 

 including all tho phenomena known in liitiliulr« ouUido tho Arctic 

 Circle, wliero ico no longer is to be found, under the nanio of glacial 

 and intcr-glacial. 



