Discuss Lamarck’s and Darwin’s theories of evolution

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Larmarck’s  theory  states  that  when  the  environment  demands  the  need  or  use  of  a  particular structure  in  the  body;  the  body  develops  it  in  response;  for  example  giraffes  used  to  have  short necks;  when  all  the  grass  was  exhausted,  they  started  stretching  their  necks  in  search  of  leaves on  trees;  therefore  they  developed  long  necks;  which  then  were  inherited  by  their  offspring; however,  when  a  structure  is  not  continually  used,  it  reduces  in  size  and  becomes dysfunctional;  this  theory  fails  to  explain  how  acquired  characteristics  become  inherited; Darwin’s  theory  suggests  that  in  nature  there  occur  struggle  for  existence;  only  those individuals  with  the  desired  adaptations  survive;  those  poorly  adapted  fail  to  compete;  and become  extinct;  there  also  occurs  variation  in  nature;  where  organisms  with  desired  adaptations pass  on  their  characteristics  to  offspring    during  reproduction;  those  poorly  adapted  fail  to reach  maturity;  and  do  not  reproduce;  therefore,  nature  selects  for  individuals  best  suited  to  an environment;  and  against  those  poorly  adapted  (natural  selection);  as  there  occurs  survival  of the  fittest;
  Max.  20  mks 

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