Goldfish breeding-Artificial selection

1 collaborator

lin xiang (Author)

WHAT IS IT?

Have fun with breeding goldfish !!!!

This model helps students observing the phenomenon of variation. Students can breed a pair of goldfish. They will see some offspring's color always slightly different from their parents. This model also demonstrates artificial selection. Students can breed the fish to test how selection pressure affects fish color evolution over time.

HOW TO USE IT?

First, push "start a fish tank" to begin. The number attached to each fish indicate its color. e.g., 21-29 are different shades of orange, 11-19 are different shades of red. The fish color may be as dark as black when the number gets close to an integer multiple of 10, such as 10,20,30.
Press "Go! Fish Go!" to let fish swim around. You may choose fish to breed at this time. You only select one fish with your desired color, and then the simulation will pair a fish with the same color to produce offspring fish. In this model, each pair of fish reproduce 30 offspring fish whose colors are determined by their parent color with some variation-either lighter or darker.
You may press "stop! Let me pick fish" to stop fish swimming so you can pick fish easily.

HOW IT WORKS?

In this model, each pair of fish reproduce 30 offspring fish whose colors are determined by their parent color number, with some variation-either lighter or darker.

CREDITS AND REFERENCES

This module is created by Dr. Lin Xiang at Weber State University. If you mention this model in a publication, we ask that you include the citations below.

Xiang, L. (2017). Artificial Selection-Fish Tank. Zoology Department, Weber State University, Ogden, UT.

Comments and Questions

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Click to Run Model

globals [x y fish-color name]

breed [fish a-fish]
breed [weeds weed]
breed [pebbles pebble]
breed [foods food]

to-report min-color
  report (round min [color] of fish) - 0.5
end 

to-report max-color
  report (round max [color] of fish) + 0.5
end 

to-report generation
  report ticks / 25000
end 

to setup
  ca

ask patches [set pcolor 87.5]
ask patches with [pycor = min-pycor] [set pcolor 35]


  create-fish 30                                                                              ;set fish
  [set color 24 + random-float 3
    set heading 90
    ifelse heading >= 0 or heading <= 180 [set shape "fish-ll"][set shape "fish-rr"]
    set size 5
    set label round color

   setposition
  ]


create-weeds 1 + random 2                                                                      ;set aquatic plants
[set color green
  set size 10 + random 3
  set shape "weed"
  setxy random-xcor min-pycor + 6 + random 2]


create-pebbles 300                                                                              ;set pebbles
[set size 1 + random-float 1.5
  set color 34 + random 5
  set shape "pebble"
  setxy random-xcor min-pycor + random-float 1.5]


  reset-ticks
end 

to setposition
  ifelse turtles-here != nobody [setxy random-xcor random-ycor][setposition]
end 

to go
  tick
every 0.1 [
swim
fish-grow
death
reproduce
pick-a-fish
do-plot]
end 

to swim
     ask fish [
    rt random-float 45
    lt random-float 45
     if [pycor] of patch-ahead 1 < min-pycor + 3 [set heading random 90]                          ;move up if get to the bottom
     if [pycor] of patch-ahead 1 > max-pycor - 3 [set heading 90 + random 90]                     ; move down if get to the surface
    ifelse heading >= 0 and heading <= 180 [set shape "fish-ll"][set shape "fish-rr"]               ; set fish side aligned with heading
    fd 0.3
     ]
end 

to set-shape
  ask turtles
  [ifelse heading >= 0 or heading <= 180 [set shape "fish 9"][set shape "fish 8"]]
end 

to death
  ask fish [if count fish >= 30 [if random 100 < 1 [die]]]
end 

to reproduce
  ask fish with [size = 5] [if count fish < 30 [hatch 1 [set color (color - 1 + random-float 2) round-color set size 0.5 set label round color setxy random-xcor min-pycor + 3 + random 2]]]
end 

to fish-grow
  ask fish [if size < 5 [set size size + 0.2]]
end 

to round-color
  if round color = 9 or round color = 10 [set color 12]
    if round color = 19 or round color = 20 [set color item random 2 [ 18 22]]
    if round color = 29 or round color = 30 [set color item random 2 [ 28 32]]
   if round color = 39 or round color = 40 [set color item random 2 [ 38 42]]
   if round color = 49 or round color = 50 [set color 48]
end 

to pick-a-fish

 clear-output
    if mouse-inside? [
    if mouse-down? [
      set x round mouse-xcor set y round mouse-ycor
      ask fish with-min [distancexy x y] [set fish-color color]
      ask fish [die]

      create-fish 1                                                                              ;set a new fish like the picked one
       [set color fish-color
        set heading 90
        ifelse heading >= 0 or heading <= 180 [set shape "fish-ll"][set shape "fish-rr"]
        set size 5
        set label round color
     setxy  -5  5
       ]

       create-fish 1                                                                              ;set second new fish like the picked one
       [set color fish-color
        set heading -90
        ifelse heading >= 0 or heading <= 180 [set shape "fish-ll"][set shape "fish-rr"]
        set size 5
        set label round color

     setxy  5  5
       ]
      ;stop
    ]]
end 

to pick-a-fish-1

 clear-output
    if mouse-inside? [
    if mouse-down? [
      set x round mouse-xcor set y round mouse-ycor
      ask fish with-min [distancexy x y] [set fish-color color]
      ask fish [die]

       create-fish 1                                                                              ;set a new fish like the picked one
       [set color fish-color
        set heading 90
        ifelse heading >= 0 or heading <= 180 [set shape "fish-ll"][set shape "fish-rr"]
        set size 5
        set label round color
     setxy  -5  5
       ]

       create-fish 1                                                                              ;set second new fish like the picked one
       [set color fish-color
        set heading -90
        ifelse heading >= 0 or heading <= 180 [set shape "fish-ll"][set shape "fish-rr"]
        set size 5
        set label round color
     setxy  5  5
       ]
      stop
    ]]
end 

to do-plot
 ;set-current-plot "Average Size of Pumpkins"
 ;plot mean [size] of pumpkins

 set-current-plot "Distribution of Fish Color"
 set-plot-x-range 10 50
 histogram [color] of fish
end

There are 2 versions of this model.

		Uploaded by	When	Description	Download
		lin xiang	over 4 years ago	adjust the interface	Download this version
		lin xiang	almost 5 years ago	Initial upload	Download this version

Attached files

File	Type	Description	Last updated
Goldfish breeding-Artificial selection.png	preview	Preview for 'Goldfish breeding-Artificial selection'	almost 5 years ago, by lin xiang	Download

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