Difference between revisions of "PhET-Simulations-for-Biology/C3/Natural-Selection/English-timed"

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||Observe the labels on the right and Roman numerals on the left of each row.
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||Observe the '''label'''s on the right and Roman numerals on the left of each row.
  
 
Generation '''P''' is shown in row I (one).  
 
Generation '''P''' is shown in row I (one).  
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||Note how the progress bar is full when a new generation begins.  
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||Note how the '''progress bar''' is full when a new generation begins.  
  
 
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||Under '''Selection Factor''', click the '''Food radio button'''.  
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||Under '''Selection Factor''', click the ''''Food' radio button'''.  
  
 
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||05:22
 
||05:22
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||Under '''Add Mutation''', click the '''Long Teeth button'''.  
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||Under '''Add Mutation''', click the '''Long Teeth''' button.  
  
 
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||05:27
 
||05:27
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||A '''text-box''', “'''Mutation coming'''” appears at the bottom of the '''simulation''' panel.  
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||A text-box “'''Mutation coming'''” appears at the bottom of the '''simulation''' panel.  
  
 
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||This indicates a mutation. You can see a picture of long teeth in the text-box.  
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||This indicates a '''mutation'''. You can see a picture of long teeth in the text-box.  
  
 
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||The '''radio buttons''' can now be clicked.  
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||The radio-buttons can now be clicked.  
  
 
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||06:03
 
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||To the left of each row are the pictures of long and short teeth.  
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||To the left of each row, are the pictures of '''long''' and '''short teeth'''.  
  
 
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||06:09
 
||06:09
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||Default selections are dominant mutation for long teeth and recessive for short teeth.  
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||Default selections are '''dominant mutation''' for '''long teeth''' and '''recessive''' for '''short teeth'''.  
  
 
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||06:17
 
||06:17
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||Observe the '''progress bar''' and the graph after the mutation has been added.  
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||Observe the '''progress bar''' and the graph after the '''mutation''' has been added.  
  
 
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||Let us allow the population to grow for another three generations after the mutation.
 
||Let us allow the population to grow for another three generations after the mutation.
  
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Keep clicking on the '''Step button'''.  
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Keep clicking on the '''Step''' button.  
  
 
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||Click on the second '''Zoom Out button''' in the graph until you see the steps.  
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||Click on the second '''Zoom Out''' button in the graph until you see the steps.  
  
 
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||06:47
 
||06:47
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||Observe how differently coloured lines appear in the graph after mutation and food selection.  
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||Observe how differently coloured lines appear in the graph after mutation and '''food''' selection.  
  
 
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||We introduced a dominant mutation for long teeth.  
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||We introduced a dominant mutation for '''long teeth'''.  
  
 
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||07:57
 
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||'''Fur Mutation'''. Set up conditions to study effects of a fur mutation on survival of rabbits.  
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||'''Fur Mutation''': Set up conditions to study effects of a '''fur mutation''' on survival of rabbits.  
  
 
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||08:06
 
||08:06
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||Keep brown fur as the dominant mutation and white fur as the recessive mutation.
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||Keep '''brown fur''' as the '''dominant mutation''' and white fur as the recessive mutation.
  
 
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||08:13
 
||08:13
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||Choose wolves as the selection factor.
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||Choose '''wolves''' as the '''selection factor'''.
  
 
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|| 09:31
 
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||Sometimes a mutation changes the phenotype of all rabbits.
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||Sometimes a mutation changes the '''phenotype''' of all rabbits.
  
 
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||09:53
 
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||'''Tail Mutation'''
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||'''Tail Mutation'''-
  
 
Set up conditions to study effects of a tail mutation on survival of rabbits.  
 
Set up conditions to study effects of a tail mutation on survival of rabbits.  
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|| 10:09
 
|| 10:09
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||Choose wolves as the selection factor.
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||Choose '''wolves''' as the '''selection factor'''.
  
 
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||10:20
 
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||Keep clicking on the '''Step button''' to move the '''simulation''' along faster.  
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||Keep clicking on the '''Step''' button to move the '''simulation''' along faster.  
  
 
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||10:28
 
||10:28
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||Click on the 2nd  '''Zoom Out button'''.  
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||Click on the 2nd  '''Zoom Out''' button.  
  
 
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|| 11:41
 
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||We can now resize the '''Pedigree''' window.
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||We can now '''resize''' the '''Pedigree''' window.
  
 
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|| 12:06
 
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||It shows that that rabbit underwent a mutation so its genotype and phenotype changed.  
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||It shows that that rabbit underwent a mutation; so its '''genotype''' and '''phenotype''' changed.  
  
 
|-
 
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||12:14
 
||12:14
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||'''Pedigree''' analysis allows study of inheritance of genes based on data about phenotypes.  
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||'''Pedigree''' analysis allows study of inheritance of '''gene'''s based on data about phenotypes.  
  
 
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||12:52
 
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||In this '''tutorial''', we have demonstrated how to use the '''Natural Selection PhET simulation'''.  
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||In this tutorial, we have demonstrated how to use the '''Natural Selection PhET simulation'''.  
  
 
|-
 
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||Using this '''simulation''', we looked at a population of rabbits for effects:
 
||Using this '''simulation''', we looked at a population of rabbits for effects:
  
−
Of mutations and selection factors
+
Of mutations and selection factors,
  
−
Of environment
+
Of environment,
  
−
On pedigree
+
On pedigree.
  
 
|-
 
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||13:13
 
||13:13
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||As an '''assignment''', observe the rabbits: For effects of mutations and selection factors in '''Arctic''' environment
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||As an '''assignment'''-
 +
observe the rabbits: for effects of mutations and selection factors in '''Arctic''' environment.
  
 
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|| 13:23
 
|| 13:23
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||After switching mutations from dominant to recessive and ''vice versa''.
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||After switching mutations from '''dominant''' to '''recessive''' and vice versa.
  
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For changes in '''pedigree''' under different conditions
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For changes in '''pedigree''', under different conditions.
  
 
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||The video at the following link summarizes the '''Spoken Tutorial project'''.
 
||The video at the following link summarizes the '''Spoken Tutorial project'''.
  
−
Please download and watch it
+
Please download and watch it.
  
 
|-
 
|-
 
||13:43
 
||13:43
−
||The '''Spoken Tutorial Project '''team conducts workshops using '''spoken tutorials''' and gives certificates on passing online tests.  
+
||The '''Spoken Tutorial Project '''team conducts workshops using '''spoken tutorials''' and gives certificates on passing '''online''' tests.  
  
 
For more details, please write to us.
 
For more details, please write to us.

Latest revision as of 18:42, 10 August 2022

Time Narration
00:01 Welcome to this tutorial on Natural Selection, an interactive PhET simulation.
00:08 In this tutorial, we will demonstrate Natural Selection, an interactive PhET simulation.
00:17 Here, I am using: Ubuntu Linux Operating System version 16.04,
00:26 Java version 1.8.0,
00:30 Firefox Web Browser version 60.0.2.
00:35 Learners should be familiar with biology and ecology.
00:41 Using this simulation, we will look at a population of rabbits for effects:

Of mutations and selection factors,

00:52 Of environment,

On pedigree.

00:55 Let us begin.
00:58 Mutations-

Mutations are alterations in the nucleotide sequence of any genetic element.

They are passed onto offspring.

01:11 Mutations may or may not change the observable traits or phenotype of an organism.
01:18 Inheritance of mutations can be dominant or recessive.
01:25 Use the given link to download the simulation.
01:30 I have already downloaded the Natural Selection simulation to my Downloads folder.
01:37 To open the jar file, open the terminal. At the terminal prompt, type: cd Downloads and press Enter.
01:48 Type: java space hyphen jar space natural-selection_en.jar.

Press Enter.

02:03 File opens in the browser in 'html' format.
02:08 This is the interface for the Natural Selection simulation.
02:13 Observe the rabbit hopping in the simulation panel.

Click the Pause button at the bottom of the interface.

02:22 Now we will explore the interface.
02:25 The interface has Simulation panel;
02:29 On the left side, Add Mutation,

Edit Genes,

02:35 in the middle- Graph,

Time until next generation progress bar,

02:42 Play/Pause button, Step button,
02:46 on the right side, Selection Factor,

Environment,

Chart.

02:54 Clicking on the Reset All button takes you back to the starting point.
02:59 Let us keep the default settings: None for Selection Factor,

Equator for Environment,

Population for Chart.

03:11 Observe the Population versus Time graph.
03:15 It shows the number of rabbits along the y-axis and time on the x-axis.
03:22 Click Play button at the bottom of the interface.
03:26 In the graph, observe how the black line moves to the right.
03:31 Keep clicking on the Step button to move the simulation along faster.
03:37 If there are no rabbits left, you will see a 'Game Over' pop-up box like this.

The text will read “All of the bunnies died!”

03:48 Click on the Play Again button to resume the simulation.
03:53 Click on Add a Friend to add another rabbit to the simulation.
03:58 Click on Pause at the bottom of the interface.
04:03 Generations of Progeny..
04:06 Observe the labels on the right and Roman numerals on the left of each row.

Generation P is shown in row I (one).

04:17 The F1 generation in row II (two) is made up of the progeny or children of generation P.

And so on until row V (five).

04:30 We will allow the population to grow until F3. This would be three steps after the mating pair.
04:41 Click Play at the bottom of the interface.
04:45 Note how the progress bar is full when a new generation begins.
04:52 The progress bar starts moving to the left as a generation starts growing.
04:58 Click Pause button.
05:01 Click the second button at the top left corner of the graph to zoom out.
05:08 You can now see the height of the next step.
05:12 The black line shows the total number of rabbits in the graph.
05:17 Under Selection Factor, click the 'Food' radio button.
05:22 Under Add Mutation, click the Long Teeth button.
05:27 A text-box “Mutation coming” appears at the bottom of the simulation panel.
05:33 Note the yellow triangle with the lightning inside.
05:37 This indicates a mutation. You can see a picture of long teeth in the text-box.
05:45 Under Edit Genes, the rows next to the Teeth label have become active.
05:52 The radio-buttons can now be clicked.
05:56 For each row, two options appear under the Dominant and Recessive columns.
06:03 To the left of each row, are the pictures of long and short teeth.
06:09 Default selections are dominant mutation for long teeth and recessive for short teeth.
06:17 Observe the progress bar and the graph after the mutation has been added.
06:22 Let us allow the population to grow for another three generations after the mutation.

Keep clicking on the Step button.

06:33 The interval between two narrow steps in the graph corresponds to a generation.
06:41 Click on the second Zoom Out button in the graph until you see the steps.
06:47 Observe how differently coloured lines appear in the graph after mutation and food selection.
06:56 Note that the timing of mutations and selection factors will affect population growth.
07:03 The legend below the graph gives the different colours and what they mean.
07:09 We introduced a dominant mutation for long teeth.
07:14 Let us look at the magenta line for long teeth, the olive line for short teeth.
07:23 Initially, the olive line is above the magenta line.

The number of short-toothed rabbits is higher than that of the long-toothed rabbits.

07:36 Later, the magenta line is above the olive line.
07:41 The number of long-toothed rabbits has increased relative to the short-toothed ones.
07:49 This means that long teeth help rabbits survive by eating the available food.
07:57 Fur Mutation: Set up conditions to study effects of a fur mutation on survival of rabbits.
08:06 Keep brown fur as the dominant mutation and white fur as the recessive mutation.
08:13 Choose wolves as the selection factor.
08:17 Allow the population to grow for another 3 generations after the mutation.
08:25 Observe how the wolves move in and out, killing the rabbits.
08:31 Brown rabbits begin to appear after the mutation was introduced.
08:37 Note that we are still looking at effects of the dominant long teeth mutation besides brown fur.
08:46 Compare numbers of rabbits having white and brown fur in the graph and simulation panel.
08:55 Initially, there are more white rabbits than brown rabbits.
09:02 Later, the number of brown rabbits has increased relative to white ones.
09:10 At the equator, with wolves killing the rabbits, brown fur is an advantage for survival.
09:18 This strategy to blend with the environment is called camouflage.
09:24 What can you say about the numbers of long and short-toothed rabbits?
09:31 Sometimes a mutation changes the phenotype of all rabbits.
09:37 If so, the graph will not compare the mutation versus the wild type (unmutated) phenotypes.
09:45 Here, there are more long-toothed rabbits than short-toothed ones.
09:53 Tail Mutation-

Set up conditions to study effects of a tail mutation on survival of rabbits.

10:02 Keep long tail as the dominant mutation and short tail as the recessive mutation.
10:09 Choose wolves as the selection factor.
10:13 Allow the population to grow for another 3 generations after the mutation.
10:20 Keep clicking on the Step button to move the simulation along faster.
10:28 Click on the 2nd Zoom Out button.
10:31 Note the number of rabbits with brown fur, long teeth and short tails.
10:38 It is higher than that of rabbits with white fur, short teeth and long tails.
10:49 Brown fur and short tails help escape from wolves.
10:55 Long teeth help survival by making it easier to eat vegetation.
11:01 Under Chart, click Pedigree.
11:04 Note the text, “Click a Bunny” at the top.
11:08 Let us click on the rabbit at the left bottom corner of the simulation panel.
11:16 Observe how the selected rabbit is framed inside a blue rectangle.
11:22 The pedigree chart appears for the rabbit framed in the blue rectangle.
11:28 Click on the top right button in the Pedigree window.
11:33 The Pedigree window is separated and the Population chart appears behind it.
11:41 We can now resize the Pedigree window.
11:46 Note the color of the previous four generations of rabbits above the selected rabbit.
11:54 Red crosses on the rabbits indicate that they are dead.
11:59 The yellow triangle with the lightning symbol inside indicates a mutation.
12:06 It shows that that rabbit underwent a mutation; so its genotype and phenotype changed.
12:14 Pedigree analysis allows study of inheritance of genes based on data about phenotypes.
12:23 Click repeatedly on the Step button.

Rabbits can be seen all over the continents on the planet Earth.

12:33 Observe the caption, “Bunnies have taken over the world!”
12:38 These are the long-term effects of the simulation under these conditions.
12:44 Do refer to Additional material provided with this tutorial.
12:50 Let us summarize.
12:52 In this tutorial, we have demonstrated how to use the Natural Selection PhET simulation.
13:00 Using this simulation, we looked at a population of rabbits for effects:

Of mutations and selection factors,

Of environment,

On pedigree.

13:13 As an assignment-

observe the rabbits: for effects of mutations and selection factors in Arctic environment.

13:23 After switching mutations from dominant to recessive and vice versa.

For changes in pedigree, under different conditions.

13:34 The video at the following link summarizes the Spoken Tutorial project.

Please download and watch it.

13:43 The Spoken Tutorial Project team conducts workshops using spoken tutorials and gives certificates on passing online tests.

For more details, please write to us.

13:55 Please post your timed queries in this forum.
13:59 This project is partially funded by Pandit Madan Mohan Malaviya National Mission on Teachers and Teaching.
14:08 Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.

More information on this mission is available at this link.

14:21 This is Vidhya Iyer from IIT Bombay, signing off.

Thank you for joining.

Contributors and Content Editors

Nancyvarkey, PoojaMoolya, Sandhya.np14

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