Download Name - wwphs

Name:
Period:
Online Lab - Flashy Fish: Sex and the Single Guppy
Purpose: to examine the role of multiple selective pressures on the evolution of guppy populations.

Google “Sex and the Single Guppy” and open the first website. Read the introduction.

Look at the “Guppy Gallery” and click on each of the fish to see more information on them. Look
at the scientific name of each, which tells you the species it is in.
1) Are all of the fish the same or different species?

Quickly click through the tabs on the bottom right of the activity to see information on predators
and the habitat these guppies inhabit.

Click on the “I’m ready to find out” link and read about Endler’s discovery.
2) Was what Endler found out from his guppy research important for evolutionary biology? If so
why?

Click on the numbers next to each pool to see what is in it.

Click on the “what causes guppy color variation?” and read some hypotheses about color
variation and change of abundance over time.

Set up and run one of the possible experiments for TEN generations (this may take a few
minutes). Record the class data in the table below.

Repeat for each scenario, nine total.
Table 1: Class Data for Flashy Fish Online Experiment
10
2
Mostly Bright Rivulus, Acara
10
3
Mostly Bright Rivulus, Acara, Ciclid
10
Mostly Drab (average)
0
4
Mostly Drab
Rivulus
10
5
Mostly Drab
Rivulus, Acara
10
6
Mostly Drab
Rivulus, Acara, Ciclid
10
Even Mix (average)
0
7
Even Mix
Rivulus
10
8
Even Mix
Rivulus, Acara
10
9
Even Mix
Rivulus, Acara, Ciclid
10
Drabbest %
Mostly Bright Rivulus
Drab %
1
Bright %
0
Brightest %
Generations
Predators
Color Types
Mostly Bright (average)
Analysis: Graph your data.
Results/Discussion:
3) Why do some guppies tend to be drabber than others (what is the advantage of being drab)?
4) Why do some guppies tend to be more colorful (what is the advantage of being colorful)?
5) Was the hypothesis that “predators are causing guppy populations to become more drab by
preying on the most brightly colored individuals and eliminating them from the gene pool”
supported by any or all of your data? If so what parts of your data and how did they support the
hypothesis?
6) Was the hypothesis that “guppy populations are evolving to more closely match their
environment” supported by any or all of your data? If so what parts of your data and how did
they support the hypothesis?
7) Was the hypothesis that “guppy populations are evolving to stand out from their environment”
supported by any or all of your data? If so what parts of your data and how did they support the
hypothesis?
8) Was the hypothesis that “female guppies are choosing to mate with the most brightly colored
males, giving those males a higher probability of passing their genes to the next generation”
supported by any or all of your data? If so what parts of your data and how did they support the
hypothesis?
9) Explain the push and pull that the environment (sexual selection and predation) has on
coloration of guppies in Endler’s pools. How did each affect the number of guppies of certain
colors and what was the result of both of them acting at the same time? This should probably
be a long paragraph to two paragraphs done on a separate piece of paper.