BOOK REVIEW The Brain fr om Ape to Man , a Cont ribut ion differentiation in its central nervous system, is to the Study of the Evo lut ion and Dev el op - more like man than any of the other Simians. men t of the Human Brai n . By Frederick Tilney, The actual interrelationship between man and ph .d ., m.d . With Chapters on the Reconstruction the great apes seems more likely to be based of the Gray Matter in the Primate Brain Stem, by upon derivation from some common or gen- Henry AIsop Riley, a .m., m.d . Foreword by Henry eralized stock which held in it the potentiality Fairfield Osborn, sc .d ., ll .d . Two volumes, New York, Paul B. Hoeber, Inc., 1928. to specialize along the anthropoid line in one direction, and through certain subhuman stages This is not a suitable medium in which to to man in another. Thus man, modern or pale- review the scientific study of the anatomy and olithic, cannot trace a direct line of descent to physiology of the brain which forms the bulk one or the other of the living anthropoid apes. of the two large volumes of Dr. Tilney’s great Of the genera of the Simiidae, the orang-outang work. Suffice it to say that the microscopic is placed by Tilney lowest in the scale, the and gross structures of the brain are studied chimpanzee next above, and the gorilla next to in the most minute detail and illustrated in the man, basing his opinion chiefly on the morpho- large number of accurate and artistic plates logical consideration of the brain structure. and figures. The work, however, contains certain Tilney gives interesting summaries of the studies features which render it of the greatest impor- made by various observers on the habits and tance to the medical historian, the student of mentality of the orang-outang, chimpanzee paleontology and all those who are interested in and gorilla. Professor Robert M. Yerkes studied the history of the origin and development of the psychology and habits of the orang-outang; the human race. The recent interest in paleo- Professor Kohler those of the chimpanzee and pathology will cause many to read with eager- Miss Cunningham observed the gorilla John ness the pages in which Tilney summarizes Daniel i, and is now studying John Daniel n. man’s rise from the most remote ages to his Probably twenty-five million years ago two present status. The attempts by certain igno- great branches of the suborder Hominidae rant fanatics to control scientific thought and parted company in the progress of their develop- discussion on the subject of evolution render ment. The first branch gave rise to the anthro- all the more necessary an intelligent knowledge poid apes in the family Simiidae, including the of it, and of the enormous amount of research orang-outang, chimpanzee and gorilla (and two work which in the last few decades has so extinct forms Dryopithecus and Paleopithecus). wonderfully elucidated points which were here- The second branch gave rise to the human tofore obscure. The present review is only family, in all its varieties of races. There are concerned with that part of Dr. Tilney’s book at least four prehistoric, now extinct, races of which deals with the problem of man’s origin man. Not one of these races can be considered and development and no attempt will be made the direct ancestor of living man any more to consider the portion devoted to anatomy than the existing genera of great apes. and physiology. The first of these extinct prehistoric races There has been much divergence of opinion was (i) Pithecanthropus erectus, remains of as to which of the three chief representatives of which, found in Java by Eugen Dubois, have so the family of the Simiidae approaches most many simian and human qualities that he nearly in its characteristics to man. Sir Richard represents a transitional stage in human evolu- Owen assigned to the orang-outang this distinc- tion. Pithecanthropus erectus had a head and tion, while others prefer the chimpanzee. face not unlike an ape, but a brain considerably Tilney states that the gorilla, because of the larger than any known simian. He walked erect and employed his hands in the use of weapons If the Australian or some other primitive and certain crude implements. His superiority race was the common ancestor of all the varied over his contemporary animals was maintained modern human race, it certainly required a with difficulty by means of his dawning ingenu- long period of evolution to produce such diver- ity and because of his slightly superior intelli- gent descendants. Sir Arthur Keith believes it gence. His brain, though larger than that of required as long a period as the entire Pleisto- any of the other apes, was much below the cene, placing Pithecanthropus even further volume of the average human brain. He had back than is usually thought. acquired some forms of speech and he lived in Tilney passes from this phase of man’s primitive communities. history to the consideration of the beginnings (2) Early in the Pre-Paleolithic Period but of the human race as far as they can be traced much later than Pithecanthropus erectus, the in cultural remains and it is this part of his remains of another extinct race of man have monumental work which is of the greatest been found, Paleoanthropus heidelbergensis. interest to those who are interested in the His antiquity is variously estimated at 350,000 history of the development of knowledge and to 450,000 years. The Heidelberg man made use culture. Beginning as a Nomadic hunter, but of crude implements of wood and stone. This little in development above the wild animals race probably became extinct within the course among whom he lived, man developed crude of 100,000 years. Because of the simian affinities mechanical appliances which enabled him to in his jaw and teeth the Heidelberg man is gain a greater supremacy in the chase. He also excluded from the direct ancestral line of man. learned to provide for his needs by cultivation Although the race of Heidelberg men became of the soil, adapting utensils for this purpose. extinct, before doing so they gave rise to His progress through the ages is marked by the another race called Homo neanderthalensis, or improvement which is shown in the implements Homo primigenus, which gave a decided which are found as landmarks of the state in impetus to the process of human evolution. which he lived when using them. The Neanderthal man has left many implements Pithecanthropus erectus lived during the which indicate that he had made marked First Glacial Period, a million years ago, and advances over his predecessors. Again, however, we know nothing positive concerning his the skull of the Neanderthal man was too ape- cultural development as we have no certain like to permit us to regard him as an ancestor of remains to show it; though some think that the modern man although his brain and the general “eoliths” found at Piltdown, Sussex, are stone structure of his body show an approach towards implements which were used by him. that of Homo sapiens. In part contemporary In the next age, the Paleolithic Period, we with both Pithecanthropus erectus and Homo find definite remains of tools or weapons which heidelbergensis a third race of man, Eoanthropus our ancient representatives constructed. Of Dawsoni, the Piltdown man, appeared in the the earliest part of the Lower Paleolithic Lower Paleolithic Period, who approaches Period, the Pre-Chellean, (beginning some the modern man more nearly than any of the 700,000 years ago) we have remains of stone others. Though some authorities regard the implements, knives, borers or drills and ham- Piltdown man as the direct ancestor of Homo mers. Except for these stone utensils there is sapiens, others regard him as belonging to nothing to indicate that he had risen much another altogether independent race. above the level of the beasts that he hunted. Thus prehistoric evidence of a common pro- Such was the status of the Heidelberg man, genitive stock for the present human race is and the Piltdown man. They were followed altogether lacking. Of all living races of man- in the next, the Chellean Period by the Neander- kind Sir Arthur Keith believes the aborigines thal man, whose implements show considerable of Australia alone have the intermediate and improvement in their construction. He made a generalized characteristics requisite for such cutting tool of flint, with the sharp edge of an ancestral form, capable of producing descend- which he cut wood, and he made arrowheads ants so diverse as the typical African and the and spearheads of flint. About 150,000 years northwestern European. ago the Neanderthal man advanced a great step when during the Mousterian Period he there are so many remains in their caves in became a cave dweller, and as such developed the south of France, is of great interest. The the conception of property holding. For some most usual supposition is that the drawings unexplained reason the Neanderthal race disap- and carvings were used as instruments of magic peared some time towards the end of the Lower to aid in the procurement of food, or in protec- Paleolithic Period. It was replaced by the tion against wild beasts, just as the Australian Cro-Magnon, a much more highly developed or African native at the present day makes race, one which we are not ashamed to claim images or draws pictures of the fish or animal as a member of the species Homo sapiens.