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by man. The owl will lodge in the church steeple. Groundbuilding birds like the black-throated bunting will sometimes build in trees if their earlier nests have been destroyed. Birds and animals which are hunted become very wary but ducks and geese quickly discover a pond where shooting is prohibited and gather there in great numbers. The multitudes of ducks and coot which assemble in the autumn on Lake Washington in the very heart of Oakland, California, have made themselves a scenic asset to the city. In parts of Africa the buffalo seems to feed only at night because of constant hunting.

RHYTHM IN NATURE

There is a rhythmic character in nature which has impressed all careful observers. The rotation of the earth producing day and night, the revolution about the sun, the ebb and flow of the tides, the waves of sound, light, electricity, illustrate this in the material world. Birth, youth, maturity, old age and death reveal it in the organic world. The alternating periods of rest and activity, the pulsations of the heart, the inhalation and expiration of the breath reveal it in the activities of organisms.

We may see this rhythm in some of the phosphorescent organisms of the ocean.

It might be supposed at first that these phosphorescent organisms are not observed to emit light during the day because of the pressure of sunlight, and that if taken into a dark room they would be found to phosphoresce just as brilliantly as at night. Such is, however, not the case, not a spark can be elicited from them even by vigorous shaking, so long as there is daylight in the outer world. But as one stands by and watches in the dark room as twilight is falling outside, although the organisms have been exposed to light all day, one observes the little lamps light up and flash out one by one like coruscating diamonds in the darkness till the whole fish is studded with flashing and disappearing light, a glorious sight in the darkness and stillness. Regularly

...

every evening the lights come out, and as regularly every morning they are extinguished, although all the intervening time the tiny living creatures have been kept in darkness.22

REFERENCES

1. B. MOORE, Origin and Nature of Life.

2. R. S. LULL, The Ways of Life, pp. 20-21.

3. Ibid., p. 11.

4. Ibid., p. 12.

5. Ibid.

6. B. MOORE, op. cit., p. 105.

7. L. J. HENDERSON, Fitness of the Environment, p. 219. 8. Α. ΚΕΙΤΗ, The Engines of the Human Body, p. 143.

9. Ibid., p. 282.

10. Ibid., p. 298.

II.

M. R. THORPE, Organic Adaptation to Environment, pp. 4-5

12. J. HANN, Handbook of Climatology, p. 58.

13. H. F. OSBORN, The Age of Mammals, p. 508.

14. Ibid., p. 508.

15. C. H. MERRIAM, "Life Zones and Crop Zones." U. S. Biological Survey, Bulletin No. 10 (1898), pp. 54-55

16. V. E. SHELFORD, Animal Communities, p. 82.

17. W. BEEBE, The Arcturus Adventure (New York, 1927).

Contains a fascinating account of stratification of life in the ocean.

18. J. HANN, op. cit., p. 38.

19. V. E. SHELFORD, op. cit., p. 31.

20. K. SEMPER, Animal Life, p. 176.

21. V. E. SHELFORD, op. cit., p. 29.

22. B. MOORE, op. cit., pp. 250-251.

CHAPTER III

HUMAN GEOGRAPHY

For I have learned

To look on nature, not as in the hour

Of thoughtless youth; but hearing oftentimes
The still, sad music of humanity,
Nor harsh nor grating, though of ample power
To chasten and subdue. And I have felt
A presence that disturbs me with the joy
Of elevated thoughts; a sense sublime
Of something far more deeply interfused
Whose dwelling is in the light of setting suns,
And the round oceans and the living air,
And the blue sky, and in the mind of man:
A motion and a spirit, that impels
All thinking things, all objects of all thoughts
And rolls through all things.

-WORDSWORTH

Man, like the other animals, is affected by the forces of nature which have just been discussed, and survives only as he develops or maintains the necessary adaptation. Lightning, flood and tornado do not spare him. He must breathe air and not carbon monoxide; must eat bread and not strychnine; must drink water and not ammonia, if he would live. In two respects only does he display any marked differences from the higher brutes about him. He has a better mental equipment and a naked body. While both of these features worry man a good deal, the former has enabled him to survive and the latter has been a big factor in the death rate of other organisms. It is man's power of adapting himself to all sorts of conditions and of modifying his habits to meet various changes which has given him a wider distribution on earth than other species save those which he takes with him, by design or accident, and for whose needs he provides. Where others fail he can find food and shelter even if he has to develop commerce to supplement local resources.

MAN'S ADAPTATION TO ENVIRONMENT

Moreover, this wide distribution is not a recent event. In all our "discoveries" of new lands like America plenty of "natives" are found and their traditions often assert a local origin with no hint of wide migrations from older homes. Easter Island is remote enough from other places but the great statues there bear silent witness to earlier inhabitants. Cain, reputed to be the son of the first man in one of our oldest accounts, goes to a new home and marries "one of the daughters of the land." We do not know where man originated and most of our stories of early migrations are legends rather than history. Tradition aside, the little evidence we have points to Asia as the original home site of man and as the center of mammalian distribution as well. Even to-day one-half of the human race lives in southwestern 'Asia. At some date, long prior to our records, man started to roam and made his way to all corners of the earth. Moreover, every group we know is far from being primitive save as compared with more advanced peoples. All understand the art of fire-making, have cooked food and wear more or less clothing. All have tools and weapons. Assuming that the genuine primitive man had neither fur nor clothing it would seem that he must have lived in the warmer regions where the supply of heat as well as food was fairly constant throughout the year. This statement suggests an important fact which must always be kept in mind; that is, that there is a correlation between man's abode and his mental and social development. Wherever man is found there is evidence that he has learned how to live under the conditions that obtain.

The fact is simple but it makes difficult a clear understanding of certain phenomena.

Race and Climate

Taking man as we know him to-day, there is little correlation apparent between his physical traits and the particular environment in which he lives. There is no important difference in the amount or the distribution of the hair of the body as between the dwellers in the tropics and the polar regions. No race has enough to be of great protection against the cold. In general the Europeans have heavy beards as compared with the Negroes, and this might be cited as an indication of climatic adaptation. The evidence is scanty. No such contrast is found between European and Negro women. The American Indians and the Asiatics are as poorly equipped as the Negroes. The inhabitants of the tropics are as likely to be fat as are the Eskimos. It has been claimed that the wider and more open nostrils of the Negro would make it difficult if not impossible for him to survive in the colder regions but many Negroes are living and prospering in New England and Canada and a Negro was with Peary on his dash to the north pole. Every one knows that there are many racial differences, but the attempt to correlate them with racial residence has failed. There is a considerable body of evidence as to the skin color of different racial groups, but the importance thereof is in dispute.

There exists, however, a widespread belief that the Negro is adapted to the tropics as no white man can be. This belief has arisen largely as a result of the effort of the white man to live in the tropics and deserves, therefore, special attention. It is to be noted that as one goes from the equator to either pole he does not pass from a zone of black folks into zones progressively lighter. To be sure, the inhabitants of south Europe are darker than the races further north, but the Swedes are markedly lighter than the Lapps of the arctics.

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