Natural Selection Bean Lab

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					Title: Natural selection Lab                       Name ______________________________________
Problem: To what extent does coloration affect survival rate in white, red, and natural colored beans? To what
extent does a food gathering "adaptation" (spoon, knife, or fork) predict survival of lab participants?
Research: (4 pts) What were Charles Darwin’s ideas about evolution? Look up the 4 basic steps of natural
1. _________________________________ 2. __________________________________________
3. _________________________________ 4. ___________________________________________

Hypotheses: (4 pts) H1: It is hypothesized that the _________bean will survive better than the others
because… ________________________________________________________________
H2: It is hypothesized that the _______adaptation will gather food best because…
Materials: Red, Natural Colored, and White Beans; Plastic knives, forks, and spoons; Dixie cups
Procedure: 1) Find a plot of grass that is approximately 30 ft by 30 ft. The instructor scatters 100 natural
beans, 100 red beans, and 100 white beans randomly over the plot while the students face away from the plot.
2) All students are given either a single plastic knife, fork, or spoon (approximately even numbers to begin
with). The number of students with each type of utensil is entered in data table 2.
3) Students "forage" for beans on the plot and use only their utensil to pick the bean up, stand up, and put it in
the cup (you cannot put beans in the cup except in the standing position).
4) After several minutes, the instructor stops students from foraging. The students count their beans and line
up in the order of the number of beans they have collected.
5) The 5 students with the lowest bean count "die" and hand in their utensil. The 5 top bean collectors have the
privilege of reproducing by coming to the instructor to get another utensil like theirs. They then hand it to one
of the "dead" students who become foragers again with a new utensil. Enter the new count of students with
each tool in data table 2 for "year 2".
6) Count the number of each type of bean that the students gathered and enter them in data table 1 row B. Do
the calculations for row C, D, & E. The instructor should gather the correct number of offspring (row D) to
scatter for the next round.
7) Steps 3 through 6 should be repeated and the numbers calculated to project what the new population would
be for year 3.
8) Graph the data results making a line graph with 3 colors of pencils. Please use a scale that will spread
your graph over 2/3 of the way up the vertical axis and over the x axis.
Answer these questions (21 pts)
1) What was the most successful (survived the best) color of bean? _____________________
2) What was the least successful (died) color of bean?
__________________________________ Why?________________________________________________
3) Give 2 examples of natural populations this may be occurring in for organisms that you have seen in your
yard or on school property. _________________________                _____________________
  Explain why the ones you observed were successful. __________________________________
4) Which of the collecting tools (adaptations) were the most and least successful?
 Most _______________Why? _______________________________________________________
Least _______________ why? _______________________________________________________
5) Give 2 examples of what these "tools" might represent in real predator populations
1. _____________________________________________________________________________
2. _____________________________________________________________________________
6) Was Darwin in error with any of his ideas on how evolution occurs? __________________
Explain. __________________________________________________________________________
7) What affect does coloration and tool type have on survival rates of organisms? _______________


Data charts: (16 pts) ½ pt each

Data table 1             White Beans     Red Beans       Natural Beans
A) population #
                            100              100              100
to begin year 1
B) # found after 5
min of foraging
C) # left in the
field (A-B)
D) # of offspring
E) # of year 2
population (D+C)
G) # found after 5
min of foraging
H) # left in the field
I) # of offspring
J)# of year 3
population (H+I)

Table 2           # Knives         # Forks         # Spoons

  Year 1

  Year 2

  Year 3
Graphs ( 12 pts ) Graph both sets of data 1. Line Graph of Showing the Effects of Coloration on Survival (graph lines A,
E, J) from data table 1. 2. Line Graph Showing the Effects of Tool Type on Survival. Data table 2

Make your graphs on graph paper. Use ½ a sheet for each graph. Spread out the years by a minimum of 5 squares
across. Put the year on the X axis. Population size on the Y. Title your graph and label each axis. Color code and make a
Conclusion: (10 pts) write this on notebook paper and attach!
Write a statement answering the problems. Use actual data to support your statement. Are your hypotheses accepted
or rejected by the data? What would you predict would happen over time to beans growing in this area?

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