SECRETS OF LIFE.

Poverty Bay Herald, Volume XLVII, Issue 15221, 20 May 1920, Page 6

SECRETS OF LIFE.

-•- | MR. HUXLEY ON HIS CLUES. ; SPEEDING UP MAN. J Julian' Huxley, the young Oxford biologist, whose remarkable experiments with thyroid extract in the direction ofmaking animals grow up or keep young were described recently, states : — j It is an old story now, as old stories go in modern science, that thyroid Extract will cure cretinism and myxedema (the former is a combination of deformity and idiocy, the latter a disease of the thyroid gland), aud anyone can look up the whole medical side of the question in any public library. But the doctors have been content merely to restore normal balance, dosing with thyriod if the patient's thyriod is deficient, operating if it is excessive. It' is tho biologists and chemists who have pushed the matter a step further. Let us take the results in detail : The thyroid gland, among other functions, regulates growth, or, more definitely, metabolism—- i.e., the various chemical processes which underlie and are the necessary foundation of life. When too little is present, the patient is sluggish in mind and body, or even dwarfish and imbecile. Too much, on the other hand, produces neivous excitability, and the patient loses flesh rapidly. Administration of thyroid to the lowest forms of life, which consist of only one cell, and reproduce by dividing into two, may cause them to reproduce half again as quickly as usual, so that, in the same time in which an ordinary animal would have divided into 256 offspring, a thyroid treated one would have produced 4,096, aud so on in geometrical proportion. Administration of thyroid to tadpoles causes them -to transform into the adult long before the proper time. By this means frogs no 'bigger than flies have been produced — something that never i occurs in Nature. Another "new tyne of organisation" can be produced by the reverse operation. If a young tadpole is deprived of its thyroid it will continue to grow, but is unable to transform into a frog. It grows and grows until it becomes 3 or 4 inches long, and may actually produce fertile eggs. Then, a substance knowni as thryoxin has been isolated from the thyriod, and can be actually manufactured from ; in-organic materials in the laboratory. This has been shown to exert a most ' powerful effect on human beings. If one milligram roughly, l-30,000th part of an ounce) is given to an ordinary man, '. his 'basal metabolism goes up two per cent.— in other words, he is, chemically speaking, working l-50th as quickly again as he was before. Future work ; atone will decide all the important points i which obviously are opened up by this ! discovery. i Finally, in frogs, it is definitely known ; that delaying the fertilisation of the eggs, for three to foiir days causes 50 ; per cent, of eggs which normally would have become females, to turn into males. These various pieces of work have been carried out in all parts of the world— for , the most part in England, the United I States, and Germany. It is hoped that our coming experiments will ena-ble us to ; correlate them ; to see, for example, ■ whether immersing developing frog's eggs in substances like thyroxin, which speed up the processes of growth, will change the proportion of the sexes. It cannot be too strongly insisted upon 1 that the phenomena of life are so complicated that no amount of theoretical prediction can take the place of : experiment. By experiment, and by experiment alone, can we hope to pierce further into the secrets of life. If the public wants to know the answers to these and similar questions, they must be prepared to set aside a definite proportion of the country's man-power in the form of research workers, and of its income, in the form of research grants for apparatus and upkeep, in order that the problems may be investigated in the patient and thorough .way which alone can be of permanent value. It is certain that any results obtained on lower animals will have some bearing on man. It may not be possible immediately to apply the results, but wo know enough and to spare to be able to assert definitely that the underlying principles are the same for all. . If we can find out this year how to control growth or sex in frogs it is not rash to prophesy that though the human organism, is much more difficult to deal with, cpving to. its being far more selfregulating, we shall probably be able to control growth and sex in the human race within the present century.