THE UNIQUENESS OF THE INDIVIDUAL 



special category of '"parentaP death, like that suffered by the 

 male salmon, is left out of count. 



We will skip blindfold over the causal nexus that relates the 

 limitation of growth to the degenerative changes of old age, 

 and ask ourselves if Bidder"'s main thesis, that marine animals 

 do not die natural deaths, is in fact true. It is a 'highly debat- 

 able problem** — that is to say, one with so little evidence to its 

 credit that no debate is in reality worth while. We have, it 

 appears, little to say about the death offish that Ray Lankester 

 did not say in his Prize Essay on longevity some eighty years 

 ago:^ ''they are not known to get feeble as they grow old, and 

 many are known not to get feebler\ ""Real evidence is practically 

 non-existent,"* said Major Flower,^ though he could tell us that 

 'under favourable circumstances some fresh-water fishes may 

 live for half a century\ The fact of the matter is that the energy 

 that might have been devoted to a theoretically straightfor- 

 ward solution of the problem has very often been dissipated in 

 digging up anecdotes about longevity from obsolete works of 

 natural history. Nor has the research been theoretically 

 prudent, for often no distinction has been made (though 

 Lankester insisted on it) between the mean expectation of life 

 and the total life span. It proves that we cannot accept the 

 claims of most of the famous human more-than-centenarians, 

 so what faith are we to have in the pedigrees of tortoises and 

 carp? No one has yet made a systematic study of whether even 

 mammals in their natural habitat do indeed live long enough to 



1 E. Ray Lankester, On Comparative Longevity on Man and the Lower 

 Animals, London, 1870. 



2 See the series of articles in the Proceedings of the Zoological Society 

 (latterly Series A), 1925, 1981, 1935-8. [Flower's last paper, published post- 

 humously, on the alleged longevity of elephants, should on no account be 

 missed: see the Proceedings of the Zoological Society, 117, p. 680, 1947. 

 The old original Jumbo ('Old Jumbo carried generations of London children 

 round the zoo in Regent's Park') died at 24, Alice at 50, and Napoleon's 

 Elephant at about 63. Flower dissects the legends of their longevity with 

 admirable skill.] 



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