BuyFindarrow_forward

Biology: The Unity and Diversity o...

15th Edition
STARR
ISBN: 9781337670319

Solutions

Chapter
Section
BuyFindarrow_forward

Biology: The Unity and Diversity o...

15th Edition
STARR
ISBN: 9781337670319

Textbook Problem

Peacock Butterfly Predator Defenses The photographs below represent the experimental and control groups used in the peacock butterfly experiment discussed in Section 1.6. See if you can identify the experimental groups and match them up with the relevant control group(s). Hint: Identify which variable is being tested in each group (each variable has a control).

images

A Wing spots painted out

images

B Wing spots visible; wings silenced

images

C Wing spots painted out; wings silenced

images

D Wings painted but spots visible

images

E Wings cut but not silenced

images

F Wings painted, spots visible; wings cut, not silenced

Peacock butterfly experiment

images

A With wings folded, a peacock butterfly resembles a dead leaf, so it is appropriately camouflaged from predatory birds.

images

B When a predatory bird approaches, a butterfly flicks its wings open and closed, revealing brilliant spots and producing hissing and clicking sounds.

images

C Researchers tested whether the wing-flicking and sound-making behaviors of peacock butterflies affected predation by blue tits (a type of songbird).

Experimental Treatment Number of Butterflies Eaten
Wing spots concealed 5 of 10 (50%)
Wings silenced 0 of 8 (0%)
Wing spots painted out and wings silenced 8 of 10 (80%)
No treatment 0 of 9 (0%)

*Proceedings of the Royal Society of London, Series B (2005) 272: 1203–1207.

D The researchers painted out the spots of some butterflies, cut the soundmaking part of the wings on others, and did both to a third group; then exposed each butterfly to a hungry blue tit for 30 minutes. Results support only the hypothesis that peacock butterfly spots deter predatory birds.

FIGURE 1.12 Testing the defensive value of two peacock butterfly behaviors.

Summary Introduction

To match: The experimental groups with their relevant control groups.

Answer

Correct answer:

Experimental

group

Control

group

AD
BE
CF
Explanation

The peacock butterfly predator defense experiment is a controlled experiment because it has both experimental and control groups.

The following are the groups that were studied:

Group A: Wing spots painted out

Group B: Wing spots visible and wings silenced

Group C: Wing spots painted out and wings silenced

Group D: Wings painted but spots visible

Group E: Wings cut but not silenced.

Group F: Wings painted, spots visible, wings cut, and not silenced

  • Group A is an experimental group that has the wings painted, and nothing is mentioned about the noise produced by the wing. Group D has the wings painted, but the spots are visible, and nothing is mentioned about the noise produced by the wing. The wing is the independent variable, and the noise is the dependent variable. Therefore, Group D is the control group for experimental Group A.
  • Group B is an experimental group that has the wing spots visible, but the noise produced by the wing is silenced. Group E has the wings cut, and the noise produced by the wing is silenced. The wing is the dependent variable, and the noise from the wing is the independent variable. Therefore, Group E is the control group for experimental Group B.
  • Group C is an experimental group that has the wing painted, but the spots are visible, and the wings are silenced. Group F has the wings painted, spots visible, and cut, and the noise produced by the wing is not silenced. The wing spot is the dependent variable, and the noise from the wing is the independent variable. Therefore, Group F is the control group for experimental Group C.

Give your grades a boost

Find quality solutions to thousands of textbooks. All for just $9.99/month

Get As ASAP

Find all the answers to your study problems with bartleby.
Textbook solutions plus Q&A. Get As ASAP arrow_forward