September 9, 1920] 



NATURE 



63 



Economic and Educational Aspects of Zoology.^ 

 By Prof. J. Stanley Gardiner, M.A., F.R.S. 



GREAT as have been the results in physical sciences 

 applied to industry, the study o< animal life can 

 claim discoveries just as great. Their greatest value, 

 however, lies, not in the production of wealth, but 

 rather in their broad applicability to human life. Man 

 is an animal, and he is subject to the same laws as 

 are other animals. He learns by the experience 

 of his forbears, but he learns also by the con- 

 sideration of other animals in relationship to 

 their fellows and to the world at large. The 

 whole idea of evolution, for instance, is of in- 

 describable value ; it permeates all life to-day ; 

 and yet Charles Darwin, whose researches did 

 more than any others to establish its facts, is too 

 often known to the public only as " the man who said 

 we came from monkeys." 



Whilst, first and foremost, I would base my claim 

 for the study of animal life on this consideration, we 

 cannot neglect the help it has given to the physical 

 welfare of man's body. It is not out of place to direct 

 attention to the manner in which pure zoological 

 science has worked hand-in-hand with the science of 

 medicine. Harvey's exfjerimental discovery of the cir- 

 culation of the blood laid the foundation for that real 

 knowledge of the working of the human body which 

 is at the basis of medicine; our experience of the 

 history of its development gives us good grounds to 

 hope that the work that is now being carried out by 

 numerous researchers under the term "experimental" 

 will ultimately elevate the art of diagnosis into an 

 exact science. Harvey's work, too, mostly on 

 developing chicks, was the starting-point for our linovv- 

 ktdge of human development and growth. Instances 

 in medicine could be multiplied wherein clinical treat- 

 ment has been rendered possible only by laborious re- 

 search into the life-histories of certain parasites prey- 

 ing often on man and other animals alternately. In 

 this connection there seems reason at present for the 

 belief that the great problem of medical science, 

 rancer, will reach its solution from the zoological side. 

 .\ pure zoologist has shown that typical cancer of the 

 stomach of the rat can be produced by a parasitic 

 threadworm (allied to that found in pork. Trichina), 

 this having as a carrying host the .American cock- 

 roach, brought over to the large warehouses of Copen- 

 hagen in sacks of sugar. Our attack on such para- 

 sites is made effecfive only by what ^%'e know of them 

 In lower forms, which we can deal with at will. Mil- 

 lions of the best of our race owe their lives to the 

 l.ibours of forgotten men of science who laid the 

 foundations of our knowledge of the generations of 

 insects and flat-worms, the modes of life of lice and 

 ticks, the physiology of such lowly creatures as 

 \mrrha and Paramecium, and of parasitic disease — 

 mal.nria, Bilharzinsis, t>'phus, trench fever, and 

 dysentery. 



Of immense economic importance in the whole 

 domain of domestic animals and plants was the re- 

 iisroverv earlv in the present rentiirv of the rompletelv 

 ' )rj'otten work of Gregor Mendel on rross-hreeding, 

 in.nde known to fiv nre«ont grnerafion largely bv the 

 I.ibours of a former president of this Association, who, 

 lik/» n true man of science, claims no credit for himself. 

 We see results already in the few years that have 

 elapsed In special breeds of wheat, in which have been 

 '•ombined with exactitude the qualities man desires. 



• From lh« openini iddre^t of ih< Pmiilant of 8«ctian D (Zoology) 

 lalirtred al the Catdilf aK'tinf of the RrilUh Anoctotlwi oa AagllM t^. 



NO. 2654, VOL. 106] 



The results are in the making — and this is true of all 

 things in biology — but can anyone doubt that the 

 breeumg of annnals is becoming an exact science? 

 \Vc have got far, p>erhaps, but we want to get much 

 further in our understanding of the laws governing 

 human lieredity; we have to establish immunity to 

 disease. Without the purely scientific study of chromo- 

 somes (the bodies which carry the physical and mental 

 characteristics of parents to children) we could "have 

 got nowhere, and to reach our goal we must know- 

 more of the various forces which in combination make 

 up what we term life. 



In agricultural sciences we are confronted with pests 

 in halt a dozen different groups of animals. We have 

 often to discover which ot two or more is the 

 diimaging form, and the difficulty is greater where the 

 damage is due to association between plant and 

 animal pests. Insects are, perhaps, the worst 

 otfenders, and our basal knowledge ot them as living 

 organisms — they can do no damage when dead, and 

 perhaps pinned in our showcases — is due to Redi, 

 Swammerdam, and to Reaumur in the middle of the 

 eighteenth century. Our present successful honey 

 production is founded on the curiosity of these men 

 in respect to the origin of life and the generation of 

 insects. The fact that most of the dominant insects 

 have a worm (caterpillar or maggot) stage of growth, 

 often of far longer duration than that of the insects, 

 has made systematic descriptive work on the relation 

 of worm and insect of peculiar importance. I 

 hesitate, however, to refer to catalogues in which 

 perhaps a million different forms of adults and young 

 are described. Nowadays we know, to a large degree, 

 with what pests we deal, and we are seeking remedies. 

 We fumigate and we spray, spending millions of 

 money, but the next remedy is in the use of free- 

 living enemies or parasities to prey on the insect pests. 

 The close correlation of anatomy with function is of 

 use here in that life-histories, whether parasitic, carni 

 vorous, vegetarian, or saprophagous, can be foretold in 

 fly-maggots from the structure of the front part of 

 their gut (pharynx) ; we know whether any maggot is 

 a pest, harmless, or beneficial. 



I will not disappoint those who expiect me to refer 

 more deeply to science in respect to fisheries, but its 

 operations in this field are less known to the public 

 at large. The opening up of our north-western 

 grounds and banks is due to the scientific curiosity of 

 Wyville Thomson and his confreres as to the exist- 

 ence or non-existence of animal life in the deep sea. 

 It was sheer desire for knowledge that attracted a 

 host of in<juirers to investigate the life-history of 

 river-eels. The wonder of a fish living in our shal- 

 lowest pools and travelling two or three thousand 

 miles to breed, very likely on the bottom in 2000 

 fathoms, and subjected to pressures varying from 14 lb. 

 to J tons per square inch, is peculiarly attractive. It 

 shows its results in regular eel-farming, the catching 

 and transplantation of the baby eels out of the Severn 

 into suitable waters which canno't, by the efforts of 

 Nature alone, be sure of their regular supply. Purely 

 scientific observations on the life-histories of flat-fish 

 — these were largely stimulated by the scientific 

 curiosity induced by the views of Lamarck and 

 Darwin as to the causes underlying their anotomicnl 

 development — and on the feeding value and nature 

 of Thisted Bredning and the Dogger Bank, led to the 

 successful experiments on transplantation of young 



