SCIENCE CONGRESS.

Otago Daily Times, Issue 20320, 31 January 1928, Page 5

SCIENCE CONGRESS.

HUMAN DEVELOPMENT. IMPORTANCE OF MUSCLES. MAN AND THE ANTHROPOID. One of the most interesting addresses delivered at the Science Congress at Hobart i.as that of Professor Colin Mackenzie, director of the National Museum of National Zoology on the importance of zoology to medica 1 science. The problem of human development, he said, had overshadowed all others in biology during the past century, and round the question of human origin a great battle had been waged, in which zoo ogists, physicians, geologists, and theologians had taken part. In the study ot human origin too much attention had been paid in the past to structure, and too little to the function on which structure depended, and of which it was the register. Much consideration had of late been given to the demonstration of prehistoric skulls iu an endeavour to till the gap between the anthropoid and the man to-day. , . . No one would deny that the positive evidence in this direction m\v accumulated was overwhelming, he suit, but just as wo had prehistoric skulls so had we also prehistoric brains, which showed primitive features side by side with the modern characteristics. No country in the world offered such a field—unfortunately fast disappearing—for the study of the human body as Australia. Its lungfish, reptiles, monotremes, and marsupials represented a living embryology different from that of the human body. Not only could structure be studied, but function as well, if, in the study of function and structure, a commencement were made with such a primitive type as_ the lowest mammal, the platypus, an animal corresponding to life on this planet icons ago, in which could be seen tho genesis of the use of limbs not only for propulsion, but for support as well. Little physiological difference was found between the monotreme and man microscopically. The organs of the platypus resembled those ot man. The difference was really, one of posture. The groat advance Irom the reptiles through the mammals up to man was in muscular action, and the advantages, intellectual or otherwise, of the erect posture were actually dependent on this. . Of all mammals, he said, man, the most intellectual, was the most erect. Erect man a lone’possessed the prefrontal brain associated with which was the development of the characteristically human forehead. Li the lowly prehistoric type evidenced by the Column skull, this development was absent. On Die erect posture, human intelligence depended. Actually little of our time was spent in the erect attitude. We spent as much of the (lay as possible sitting or reclining, and when standing we sought relief from the efforts erectness demanded in supporting ourselves by any convenient object. One could not regard the time spent by the human race to-day in the motor car as conducive to muscular impro\ement. In spite of hospitals, drugs, and nreventive measures, it would c cm that ns old diseases disappeared or tended to lose their virulence, new one.-. took their place. As human development had been on physiological and not pathological lines, to obtain a knowledge ot the factors that constituted health, we must know the history of human development, and this could only be obtained by a study of Nature’s own experiments. Only along this line could a problem of coll multiplication such as cancer be attacked. PHYSICAL CULTURE. Professor M’Konzic, in discussing physical culture, said that to develop a sound muscular system we must not only have rational exercise, but rational vest as well. Km h exercises as golfing, tennis, and long walks might, to the city man, engaged in mental activities, act as an irritant, since, more often muscular renose was indicated. The cause of dullness in tho school child might be tho result of faulty seating accommodation. The’ child was compelled to sit erect on a seat without a back, and was forbidden to rest the head on tho hands, with the result that mental effort was expended, not onlv on lessons, but on balance as well. How often was our enjoyment of a play or lecture spodt through a similar cause. Tho laziness of the Aos-tral-’an aboriginal had a physiological basis. ' , Probably, no game in the world, lie said, exercised the erect posture functions more than the Australian game of football. It was founded on physiological lines, and had been no small factor in the physical development of the nation. In the hospitals of the future a primary consideration in treatment should be given to Nature’s methods., An essential in any public hospital was a department of myology, in which scientific examination could be made for muscular defects, and their importance assessed. VETERINARY PROBLEMS. The problem of pleuro-preumonia contagiosa in Australia was the subject of an address before the veterinary section by Dr Max Henry, chief veterinary surgeon, Department of Agriculture, New South Wales. Pleuro-pnoimiouia contagiosa, said Dr Henry, ranked as one of the three great cattle plagues of the world. Australia had been affected for close on CO years. The disease was introduced into Victoria in 1858. and in four years all the mainland States became infected, but Tasmania had always remained free. The most dangerous method of spreading" the disease, Dr Max Henry said, was the splitting up of mobs of store cattle in country saloyards. Diagnosis was difficult in many oases because the symptoms might he so transient. Animals apparently recovered, but were often chronically affected, and became what were known as “ carriers." Many attempts had been made to obtain reliable biological methods of diagnosis. Since many areas of thee continent were now free from Ibe disease there would appear to be ; • . eason why attempts should not he m ■ I ) maintain that freedom. Such an ato... t Was being made on the north coast of Now South Wales. The problems which required solution were the destruction of all affected animals, the maintenance of control in contacts, the elucidation of a roh'nble biological method of diagnosis, and the working out of a more satisfactory method of immunisation. EARTH MOVEMENTS. The movements of the earth’s crust and their effect noon the life of tho globe were referred to by Professor Leo A. Cotton, of the University of Sydney, in bis presidential address before tnc geology and geography section. Movements of the crust, ho said, were but the surface expressions of events which originated in the deeper zones beyond the limits of direct investigation. Therefore, it was necessary to study the interior of the earth in ntheF ways. First in importance wore those studios of earthquake phenomena which constituted tho very modern science of seismology. By the use of delicate instruments it was now possible to study the effects of earthquakes at great distances. , and many earthquakes were of such magnitude that they were recorded by instruments all over tho world. Tho vibrations set up by an earthquake shock were of three kinds. One of those travelled in the earth’s surface crust, while, the other types progressed through the interior of the earth. Each of the three kinds of vibrations had a different velocity; and from the velocities important conclusions could be drawn regarding the ! ' : nd of substances through which they passed. Thus there was a means of probing deeply into tho interior of the earth. There were also other methods based upon astronomical and geodetic observations, which revealed something of the nature of the earth’s interior. Gravitational forces wore a primary cause of earth movcme<jr»., Professor Cotton ’obsc; vcd. They wc.'i the result, also, of radio-active heat iu the outer layers.