6 APRIL 1956, Page 34

Mendelian Merry-Go-Round

A GUIDE TO EARTH HISTORY. By Richard Carrington. (Chatto and Windus, 21s.) OFFHAND, I can think of no book which covers more detail in less space than this one. It starts with chaos. Before you can say Claudius Ptolemy of Alexandria, the universe has been tied up in a neat cosmic parcel and the author has galloped off on a surveY of the earth extending over three or four thousand million years which is, of course, what he promised to do on the title page. men certainly begin to emerge, shyly, on page 194, but by that time the reader will probably be convinced that Mr. Carrington is mostly concerned about the weird and wonderful organisms, large and small, which moulded us into the Mendelian merry-go-round. It seems that prehistory, like the relationship of less distant incidents, depends entirely on the observer's viewpoint. Chemists and physicists could, no doubt, provide a satisfactory explanation for the whole of creation in terms of a 100-odd elements and the laws of thermodynamics; a really detached earth-historian might regard the totality of life merely as a fanciful kind of rust afflicting the skins of certain lukewarm minor planets. But the author is clearly a biologist by interest, and the greater part of his book relates how one beast followed another up the evolutionary tree. He is also a catastrophist, that is to say, his geological periods are marked violently by evolutionary upheavals, holocausts and the like which bring to mind that awful Walt Disney picture of the last stegosaur, or some such reptile, staggering away from the last dried-up water-hole in the last Mesozoic plain. But surely it took millions of years of Eocene sunlight to warm up the blood of the mammals sufficiently for them to be able to disregard the worst of the weather? I am all for smoothing out the time-scale. And then, again, Mr. Carrington is perhaps over-preoccupied by the neces- sity of getting everything in, particularly in the early chapters, when theory follows theory with an effect as parching as the Greek names of fossils of Devonian fish. Speculation about the

creation of organic life from inorganic `un-life' is doubly pre- carious today when many physicists seem to be of the opinion that the young earth was not subject to the so-called constants of physics. But above all this is a courageous, creditable and clearly written book, which must represent a mountain of labour.

JOHN HILLAI3Y