THE CRADLE OF THE RACE.

Otago Daily Times, Issue 20330, 11 February 1928, Page 10

THE CRADLE OF THE RACE.

Wondeb is sometimes expressed at the scarcity of fossils, and the doubt on the theory of man's descent has been strengthened in consequence. It is not surprising, however, that missing links are infrequently discovered. It is, after all, by a rare chance that any particular link can be preserved. The remains of the animal or plant must in their nature be preservable. The environment where the animal fell must be such as would prevent complete decomposition. After the lapse of many thousands of years geologists must happen in a big world to delve in exactly the place where such animals fell under conditions favourable to their preservation away back in the dateless past. Moreover, tho search for fossils as data for evolutionary theory is a comparatively recent line of activity, and .everything cannot be found at once. Out of all tho teeming forms of life existing to-day, how many are likely to be found in a state of preservation in, say, a million years' time? Discoveries, however, are continually being made, all of which contribute their quota as evidence, just as discoveries of teeth iu the dried bed of the Vaal River, Transvaal, have this week been regarded as supporting the theory that Southern Africa was the possible cradle of man. The wonder is not that so. few links connecting the higher and lower creatures have been found, but that there are so many. It happens that in some places, as iu the frozen soils of Siberia, the flesh, the skin, the hair, the viscera, and even the contents of the stomach are sometimes preserved in a wonderfully complete condition. Certain parts of extinct species of cuttle-fishes have escaped destruction, and been retainea in rocky formations s for enormous periods of geological time. In tho deeper waters, far removed from the shore, large masses of organic limestones or richly fossiliferous mud are slowly built up, and it is these that tell us so much of the earth's life-story. If the most ancient rocks contain the fewest fossils, it is not necessarily because life flourished with less vigour and in less variety of form in tho earlier epochs, but because the ravages of time have obliterated what otherwise might have remained. Moi-eover, denudation has been at work and swept away great masses of fossiliferous rock and strewn them on the ocean beds, thus putting them largely beyond reach. Of the fossils preserved in the strata, merely an infinitesimal fraction of the whole can have been collected and submitted to scientific inquiry. There are numerous ways in which fossils are preserved. Some are the footprints of animals, the trails or casts of worms, the burrows made in ■ subsequently petrified timber by boring insects, all aiding the scientist to a knowledge, however limited, of the epochs to which they belong. Some remains are mere casts or impressions, like the traces of leaves on the beds of sandstone, or the hollow cavities left when the bones of some extinct animal have been entirely dissolved away. In the majority of instances fossil remains are parts only of the animal to which they belonged. Scales of extinct fossil fishes have their microscopic features preserved in as perfect a condition almost as those taken from their recent representatives. Mammoths are sometimes preserved complete ; so also are flies (in amber) and other minute structures. Needless to say, fossils are of the greatest importance to the geologist, not only because of the information they afford as to the history and development of the animal kingdom in general, but because of the indications they give as to the ages of the beds whence they are derived and as to the conditions under which they were deposited. The discovery even of a few teeth, as in the present instance in South Africa, is of great value to the discerning who know how to read their story, and is to be welcomed as part of the handwriting of Nature in her efforts to give her wonderful message to the world.