THE OLDEST FORMS OF ANIMAL LIFE

Press, Volume LXXII, Issue 21940, 14 November 1936, Page 13

THE OLDEST FORMS OF ANIMAL LIFE

Memoir on Fossils of the Late PreCambrian (Newer Proterozoic), from the Adelaide Series, South Australia. By Sir T. Wv Edgeworth David and Dr. K., J. Tillyard. Angus and Robertson Ltd. 123 pp. (7/6.) [Reviewed by Dr, R. S. ALLAN.! The oldest, well-preserved fossils have been found in many parts of the world in strata referred to by geologists as the Cambrian System. This is the oldest subdivision, of the Palaeozoic Era—the time of ancient life. Cambrian fossils,. t{ie hard parts of organisms which lived some t. 00,000,000 years ago, are found in great variety; and the types known, representative of all the primary divisions of the invertebrates, have already at this early date attained a surprising degree of specialisation. This abundance of Cambrian life implies a long antecedent eyoluti on of which no trace remains in the rocks. Apart from the claims advanced in the book under v review geologists have searched in. vain for traces of animal life in the vast thicknesses of rocks which were formed during the immensities of time called collectively pre-Cam-brian. • In 1928 Sir Edgeworth David astonished His colleagues by an-, nouricing his discovery of fossils from certain pre-Cambrian rocks in South' Australia, His subsequent investigation of these remarkable Relics “is a record of unwearying patience and unflagging energy and enthusiasm, combined with that keen insight which was one of his chief characteristics,” and tVas continued to his death, so universally lamented by all who knew him, in 1034. In 1931 he invited and secured the co-operation of "Dr, R. J, Tillyard, a man whose scientific worth is well known in this Dominion, and with the aid of a grant from the Royal Society of London they quarried for and obtained more specimens of fossils. Now, in 1936, comes a memoir embodying the results of the joint labours of both men, each preeminent in his chosen sphere. Sir Edgeworth regarded his discovery as his greatest contribution to geological science. He was convinced that his specimens represented “beyond all doubt definite remains of animal fossils.”' On reading this book one is amazed by the evidence of untiring energy, by the unquenchable enthusiasm and the patience and perseverance of Sir . Edgeworth David; one is also impressed by the clear statements and arguments of the junior author. But a doubt .remains; have these workers, in entering a field not quite their own, been “carried away by the glamour of the research”? Have they really lifted “the veil that for ages has hidden pre-Cambrian life”? t It is too soon to say. This work, one gathers, deals with but a few of the fossils discovered* Those that are described are poorly preserved. The authors claim .to have found animals that lived 200,000,000 years before the Cambrian Period; these include giant worms and Arthropods of great size. Dr. Tillyard describes and. illustrates a form which he suggests represents the sole known representative of a new subdivision of animals. This, form, named Protadelaidea, belongs to the phylum Arthropoda which includes Crustacea, insects, and the important fossil groups, the trilo,bites, and the - The hew form dad not give rise to any of these groups, l?ut had a common ancestor with them in early preCambrian time.

This memoir is, bound to a stir in the scientific world. It will be read, one fears, with a mixture of amazement and scepticism. All who knew and loved Sir Edgeworth will hope that future research will vindicate his claims and establish beyond doubt "some vision of this early world, a vision, of course, very imperfect, but never? theless full of the glamour of fresh truth revealed.”