200 MISCELLANEOUS OBJECTIONS TO THE 



arrange his genealogical tree '^ in such a manner that all 

 the descendants have longer lives than their progenitors! 

 Cannot our critics conceive that a biennial plant or one of 

 the lower animals might range into a cold climate and 

 perish there every winter; and yet, owing to advantages 

 gained through natural selection, survive from year to 

 year by means of its seeds or ova? Mr. E. Ray Lankester 

 has recently discussed this subject, and he concludes, as 

 far as its extreme complexity allows him to form a judg- 

 ment, that longevity is generally related to the standard of 

 each species in the scale of organization, as well as to the 

 amount of expenditure in reproduction and in general 

 activity. And these conditions have, it is probable, been 

 largely determined through natural selection. 



It has been argued that, as none of the animals and 

 plants of Egypt, of which we know anything, have changed 

 during the last three or four thousand years, so probably 

 have none in any part of the world. But, as Mr. G. H. 

 Lewes has remarked, this line of argument proves too 

 much, for the ancient domestic races figured on the 

 Egyptian monuments, or embalmed, are closely similar or 

 even identical with those now living; yet all naturalists 

 admit that such races have been produced through the 

 modification of their original types. The many animals 

 which have remained unchanged since the commencement 

 of the glacial period, would have been an incomparably 

 stronger case, for these have been exposed to great changes 

 of climate and have migrated over great distances; whereas, 

 in Egypt, during the last several thousand years, the con- 

 ditions of life, as far as we know, have remained absolutely 

 uniform. The fact of little or no modification having 

 been effected since the glacial period, would have been of 

 some avail against those who believe in an innate and 

 necessary law of development, but is powerless against the 

 doctrine of natural selection or the survival of the fittest, 

 which implies that when variations or individual differences 

 of a beneficial nature happen to arise, these will be pre- 

 served ; but this will be effected only under certain favor- 

 able circumstances. 



The celebrated palaeontologist, Bronn, at the close of his 

 German translation of this work, asks how, on the prin- 

 ciple of natural selection, can a variety live side by side 



