Question

QUESTION 21

1. An island has recently undergone a protracted period of drought. You are curious about whether the drought has had any effect on the size of animals that inhabit this island. Luckily, before the start of the drought, the body lengths of several individuals of a species of gecko were measured and recorded. You have been allowed to visit this island to conduct your study and manage to catch 10 of the same tagged individuals. You measure the body lengths of each.

   a. Formulate an experimental hypothesis, given the information you have been provided. [2]

   b. What is your null hypothesis? [1]

   c. Fill in the missing information in the table provided. [4]

   t-calc	2.06
   t-critical
   d.f
   p-value
   Confidence %

   d. What is your conclusion regarding both your hypotheses? [4]

   e. What are two methods/ways by which you can strengthen your results/ correlation of data? [4]

Answer 1

a, b. Experimental hypotheses

null hypothesis : Draught has an effect on body size of gecko animals

Alternate hypothesis : drought changes the body size of gecko animals

C. t-critical = 2.262 df= 10-1=9 p= 0.05

Confidence interval = 0.95 or 95%

d. Since t-calc<t-critical at given degrees of freedom Null hypothesis is accepted and alternate hypothesis is rejected. Therefore Draught has not caused any significant change in body size.

e. One way to strengthen the results is to increase the number of animals /measurements (sample size).