EVOLUTION AND MAN S PLACE IN NATURE 



The lower life, being the more abundantly produced 

 is also largely sacrificed for the sake of the higher. 



Domestication of animals has brought to focus 

 varieties of evidence guiding to scientific conclusions. 

 The facts so utilised, being generally familiar, need 

 not have extended reference. Some special line of 

 scientific observation may best servo requirements 

 Let us take the changes occurring in the young stage 

 of some osseous fishes, as those wore traced by Agassiz 

 Iis observations include changes in the structure of 

 ishes, changes in the tail, in development of 

 pigment cells, and transposition of an eye from one 

 side of the head to the other. These are incidents 

 in the adaptation of the young of flat fishes to the 

 modes of life peculiar to the species at a later stage 

 The change of situation of the eye will strikingly 

 illustrate the power of adaptation claimed for all life 

 Young flounders first swim vertically, as most fishes 

 do and only after a time turn over on their side 

 While still in the egg, and for some time after 

 hatching, the eyes of the two sides are placed sym 

 metrically on each side of the longitudinal axis 

 The change of position of one of the eyes, so as to 

 place both on what is to bo the upper side, is effected 

 very early m life, while all the facial bones of the 

 skull are sti 1 cartilagenous. The first change of 

 position of the eye to be transferred is its slight 

 advance towards the snout; this is soon followed &quot;by 

 slight movement of rotation. When the young 



ot y e m , profile&amp;gt; th cye n the biM side 



now slightly above and in advance of that on the 

 coloured side. With increasing age, the eye on the 

 blind side rises h:gher and higher towards the median 



