Vicuñas_pasto

breed [vicuñas vicuña]
vicuñas-own [ age
              energy
]

to setup
  clear-all
  ;grow-grass
  set-default-shape vicuñas "vicuña"
  create-vicuñas number [
    set size 4
    set age 0
    set energy random 20
    setxy random-xcor random-ycor
    ]
  reset-ticks
end 

to go
  if not any? vicuñas [ stop ]
   grow-grass
   ask vicuñas
  [ move
    eat-grass
    reproduce
    death ]
  tick
end 

to grow-grass
  ask patches [
    if pcolor = black [
         if random-float 100 < grass-grow-rate
        [ set pcolor lime + 3 ]
  ] ]
end 

to move
  rt random 50
  lt random 50
  fd 1
  set energy energy - 1
  set age age + 1
end 

to eat-grass
    if pcolor = lime + 3
  [ set pcolor black
    set energy energy + grass-energy ]
end 

to reproduce

  if energy > birth-threshold
    [ set energy energy / 2
      hatch 1 [
        fd 1
        set age 0
        set energy random 20] ]
end 

to death
  if energy < 0 [ die ]
  if age > 50 [die] ;longevidad maxima
end