﻿CAMOUFLAGE 
  — 
  FRIEDMANN 
  271 
  

  

  have 
  testified 
  to 
  the 
  fact 
  that 
  the 
  wing 
  tilting 
  is 
  not 
  a 
  casual 
  or 
  acci- 
  

   dental 
  reaction, 
  but 
  is 
  definitely 
  correlated 
  with 
  the 
  direction 
  of 
  sun- 
  

   light 
  and 
  also 
  to 
  the 
  approach 
  of 
  enemies. 
  Another 
  group, 
  without 
  

   the 
  wing-tilting 
  habit, 
  always 
  seem 
  to 
  orient 
  the 
  body 
  with 
  respect 
  to 
  

   the 
  direction 
  of 
  sunlight 
  when 
  alighting 
  on 
  any 
  object 
  so 
  that 
  the 
  

   shadow 
  cast 
  by 
  the 
  wings 
  (which 
  are 
  the 
  largest 
  part 
  of 
  the 
  creature) 
  

   is 
  reduced 
  to 
  a 
  thin, 
  inconspicuous 
  line 
  instead 
  of 
  a 
  sizable 
  dark 
  area. 
  

   In 
  animals 
  with 
  dorsoventrally 
  flattened 
  or 
  depressed 
  body 
  form, 
  

   shadows 
  are 
  often 
  reduced 
  by 
  the 
  animal's 
  squatting 
  closely 
  against 
  

   the 
  ground 
  or 
  branch 
  or 
  whatever 
  the 
  creature 
  is 
  resting 
  on, 
  but 
  in 
  

   many 
  cases 
  there 
  are 
  structural 
  features 
  which, 
  whatever 
  their 
  other 
  

   functions 
  may 
  or 
  may 
  not 
  be, 
  do 
  serve 
  to 
  reduce 
  shadow 
  by 
  covering 
  

   it 
  from 
  sight. 
  Many 
  reptiles 
  and 
  amphibians, 
  such 
  as 
  the 
  horned 
  toad, 
  

   have 
  lateral 
  finlike 
  flanges 
  on 
  the 
  tail 
  which 
  not 
  only 
  help 
  to 
  cover 
  

   the 
  shadow 
  that 
  would 
  otherwise 
  be 
  visible, 
  but 
  by 
  their 
  gradual 
  slope 
  

   from 
  the 
  top 
  of 
  the 
  tail 
  to 
  the 
  substratum 
  throw 
  little 
  if 
  any 
  shadow 
  

   beyond 
  themselves. 
  These 
  flanges 
  make 
  for 
  unbroken 
  continuity 
  be- 
  

   tween 
  the 
  more 
  substantial 
  part 
  of 
  the 
  animal 
  and 
  its 
  immediate 
  

   surroundings. 
  The 
  sides 
  of 
  the 
  body 
  are 
  flattened 
  out 
  into 
  longitudinal 
  

   flanges. 
  As 
  we 
  have 
  already 
  noted 
  in 
  discussing 
  constructive 
  shading, 
  

   the 
  effect 
  of 
  false 
  shadows, 
  such 
  as 
  those 
  of 
  the 
  leaf 
  vein 
  ridges, 
  may 
  

   be 
  brought 
  about 
  by 
  pattern 
  in 
  some 
  creatures, 
  such 
  as 
  certain 
  

   caterpillars. 
  

  

  DISAPPEARING 
  COLORATION 
  

  

  All 
  the 
  items 
  examined 
  so 
  far 
  have 
  to 
  do 
  with 
  animals 
  that 
  are 
  more 
  

   or 
  less 
  stationary. 
  There 
  are 
  also 
  a 
  great 
  many 
  animals 
  that 
  show 
  

   bright 
  patches 
  or 
  patterns 
  when 
  in 
  motion 
  but 
  suddenly 
  conceal 
  them 
  

   when 
  alighting. 
  From 
  the 
  standpoint 
  of 
  the 
  pursuer 
  it 
  is 
  very 
  con- 
  

   fusing 
  to 
  be 
  chasing 
  something 
  with 
  a 
  bright, 
  vivid 
  telltale 
  mark 
  and 
  

   then 
  find 
  it 
  suddenly 
  vanishing. 
  It 
  often 
  results 
  in 
  the 
  pursuer 
  racing 
  

   on 
  beyond 
  the 
  hiding 
  prey 
  and 
  thereby 
  losing 
  all 
  chance 
  of 
  obtaining 
  

   it. 
  Color 
  patterns 
  of 
  this 
  disappearing 
  type 
  are 
  of 
  two 
  main 
  kinds, 
  

   the 
  one 
  depending 
  on 
  the 
  distinctive 
  pattern 
  being 
  actually 
  covered 
  

   when 
  at 
  rest, 
  the 
  other 
  depending 
  on 
  differential 
  orientation 
  to 
  light. 
  

   In 
  the 
  first 
  type 
  the 
  cases 
  may 
  be 
  very 
  simple, 
  involving 
  merely 
  the 
  

   disappearance 
  of 
  the 
  bright 
  color 
  area, 
  or 
  they 
  may 
  involve 
  elaborate 
  

   protective 
  color 
  resemblance 
  to 
  the 
  substratum 
  on 
  the 
  part 
  of 
  the 
  

   covering 
  portions 
  of 
  the 
  body. 
  As 
  may 
  be 
  expected, 
  the 
  second 
  is 
  far 
  

   more 
  effective 
  as 
  concealment 
  than 
  the 
  first, 
  but 
  in 
  both 
  the 
  element 
  

   of 
  confusing 
  surprise 
  is 
  equally 
  present. 
  An 
  example 
  of 
  simple 
  dis- 
  

   appearing 
  coloration 
  is 
  the 
  common 
  North 
  American 
  woodpecker, 
  

   the 
  flicker 
  (Colaptes 
  auratus). 
  In 
  flight 
  this 
  bird 
  shows 
  a 
  large 
  con- 
  

   spicuous 
  white 
  patch 
  on 
  the 
  rump, 
  and 
  bright 
  golden 
  yellow 
  under- 
  

   sides 
  on 
  the 
  wings 
  and 
  tail. 
  On 
  alighting 
  these 
  parts 
  are 
  immediately 
  

  

  