Question

A previous group of students wanted to investigate the factors that contribute to female fecundity (total number of eggs a female lays).  They wondered if the female’s body weight might play a role.  The students collected and weighed 15 newly-emerged virgin female bean beetles.  Each female was mated and given plenty of black-eyed peas on which to lay eggs.  Each day the students checked the beans for eggs, counted the number of eggs, and gave the female fresh beans.  When the female died, the students added up the total number of eggs each female laid.

1. What is the independent variable?  What are the potential values for this variable? What is the dependent variable?  What are the potential values for this variable?
2. What are the study subjects?  Be specific!
3. What might be the researchers’ hypothesis?
4. What type of scientific study did the researchers conduct?
5. If this study is an experiment, what are the treatments?  Label the treatments as either experimental or control.
6. What was the sample size of this study?
7. List three potentially confounding variables that were or should have been controlled in this study.

Answer 1

The experiment is a controlled scientific study aiming to study the effect of body weight on the egg-laying capacity in female bean beetles.

1. The study consists of independent and dependent variables.

Independent variables include the selection time of the beetle, mating time, selection black-eyed peas (number, variety, and quality), duration of exposure of the bean to female beetles.  These have a significant impact on the outcome viz., number and quality of the beans reflect on the egg-laying.

Dependent variable: Dependent variables include duration taken to lay eggs, weight, and number of the eggs and viability of the eggs.

2. The subject of the study was the impact of the weight of the female Beatles on their fecundity.

3. Researchers may be hypothesizing that the weight of the female Beatles affects their egg-laying ability.

4. This study falls under the controlled quantitative analysis type of scientific study.

5. The study is not assessing the effect of treatment but controlled qualitative, where it assesses the relationship between the number of an egg laid and body weight.

6. a) Type of the male used in mating.

b) variety of the female used.

c) other variables such as season (month) of the study and lighting and mating conditions.