﻿ADAPTIVENESS 
  AND 
  PURPOSIVENESS 
  321 
  

  

  Of 
  great 
  interest 
  are 
  the 
  co-ordinating 
  functional 
  adjust- 
  

   ments 
  which 
  secure 
  smooth 
  working. 
  A 
  fine 
  example 
  is 
  the 
  

   heat-regulating 
  arrangement 
  or 
  thermotaxis 
  of 
  birds 
  and 
  

   mammals, 
  which 
  adjusts 
  the 
  production 
  of 
  animal 
  heat 
  so 
  

   as 
  to 
  meet 
  the 
  loss. 
  Superimposed 
  on 
  this, 
  as 
  it 
  were, 
  are 
  

   the 
  special 
  adjustments 
  which 
  bring 
  about 
  winter-sleep 
  in 
  

   hibernating 
  mammals. 
  And 
  there 
  is 
  no 
  internal 
  regulation 
  

   more 
  worthy 
  of 
  our 
  admiration 
  than 
  the 
  manner 
  in 
  which 
  

   the 
  mother-mammal 
  is 
  functionally 
  prepared 
  for 
  the 
  ante- 
  

   natal 
  development 
  of 
  the 
  offspring 
  and 
  its 
  nurture 
  after 
  birth. 
  

   The 
  adaptive 
  regulatory 
  role 
  of 
  the 
  internal 
  secretions 
  is 
  

   one 
  of 
  the 
  most 
  fascinating 
  chapters 
  in 
  modern 
  physiology. 
  

  

  Inexhaustible, 
  again, 
  are 
  the 
  illustrations 
  of 
  the 
  manner 
  

   in 
  which 
  living 
  creatures 
  are 
  adapted 
  to 
  the 
  particular 
  con- 
  

   ditions 
  of 
  their 
  life. 
  The 
  mole, 
  living 
  underground, 
  is 
  

   adapted 
  in 
  its 
  short 
  vertical 
  fur 
  and 
  in 
  the 
  absence 
  of 
  an 
  

   ear-trumpet 
  to 
  the 
  reduction 
  of 
  friction 
  in 
  burrowing; 
  its 
  

   hand 
  has 
  become 
  an 
  extraordinary 
  shovel 
  and 
  its 
  shoulder- 
  

   girdle 
  and 
  associated 
  musculature 
  are 
  powerfully 
  developed; 
  

   the 
  minute, 
  imperfectly 
  developed 
  eye 
  is 
  good 
  enough 
  for 
  

   what 
  is 
  required 
  of 
  it, 
  and 
  it 
  is 
  hidden 
  by 
  hair 
  so 
  that 
  it 
  

   does 
  not 
  get 
  rubbed 
  and 
  become 
  a 
  source 
  of 
  weakness; 
  and 
  

   so 
  the 
  zoologist 
  goes 
  on. 
  

  

  We 
  may 
  also 
  refer 
  to 
  the 
  theoretically 
  very 
  interesting 
  

   inter-organismal 
  adaptations. 
  These 
  may 
  be 
  between 
  or- 
  

   ganisms 
  of 
  the 
  same 
  kind, 
  between 
  parent 
  and 
  offspring, 
  

   between 
  male 
  and 
  female. 
  Even 
  the 
  male 
  parent 
  may 
  be 
  

   adapted 
  to 
  the 
  offspring 
  as 
  we 
  see 
  in 
  the 
  pouch 
  of 
  the 
  

   sea-horse, 
  and 
  in 
  the 
  still 
  more 
  striking 
  case 
  of 
  the 
  ISTew 
  

   Guinea 
  fresh-water 
  fish 
  called 
  Kurtus, 
  where 
  a 
  hooked 
  bony 
  

   process 
  grows 
  from 
  the 
  top 
  of 
  the 
  male's 
  head 
  at 
  the 
  breed- 
  

   ing 
  season 
  and 
  serves 
  for 
  the 
  suspension 
  of 
  the 
  bunch 
  of 
  

  

  