turtles-own [ age ]

to setup
  ca
  cct 3 [
    set color pink
    fd 2
  ]
end

to go
  ask turtles [
    wander
    reproduce
    grow-old
  ]
  plot count turtles
  if count turtles = 0
    [ stop ]
end

to grow-old
  set age age + 1
  if (age > 50) [ die ]
end

to wander
  rt random-float 360
  fd 1
end

to reproduce
  if (color = pink and random 5 = 0) [
    hatch 1 [
      if random 10 > 0 [set color blue]              ;9 of 10 hatched turtles are made blue
      set age 0
    ]
  ]
end
@#$#@#$#@
GRAPHICS-WINDOW
318
10
661
374
18
18
9.0
1
10
1
1
1

CC-WINDOW
10
281
306
427
Command Center

BUTTON
27
220
82
253
setup
setup
NIL
1
T
OBSERVER

MONITOR
167
212
269
261
count turtles
count turtles
3
1

BUTTON
86
220
141
253
go
go
T
1
T
OBSERVER

PLOT
10
10
311
195
Population
time
count
0.0
200.0
0.0
50.0
true
false
PENS
"number" 1.0 0 -16776961 true

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WHAT IS IT?
-----------
This code example demonstrates the HATCH command.  

Blue turtles never reproduce.  Pink turtles have a one-in-five chance of reproducing at each time tick.  Each turtle's life lasts 50 ticks.  Nine out of ten baby turtles are blue.

The turtles created by HATCH are exact duplicates of their parents, so it is necessary to reset each new turtle's age to 0 inside the HATCH command.
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default
true
0
Polygon -7566196 true true 150 5 40 250 150 205 260 250

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NetLogo 2.0alpha1
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