Investigating Variation

Question 1

What is interspecific variation?

Answer 1

Differences between species

Question 2

What is intraspecific variation?

Answer 2

Differences between organisms in a population of one species

Question 3

What do quantitative investigations of variation within a species involve?

Answer 3

• collecting data from random samples
• calculating mean value and the standard deviation
• interpreting mean values and their standard deviations

Question 4

How do you decide whether an outlier is an anomaly or the result of natural variation?

Answer 4

• anomalies should be identified when raw data is collected
• most of the outlier results can be explained as a result of variation if measurements have been made accurately
• unless you are certain that a particular value is a genuine measurement anomaly, you can’t ignore it when you calculate mean and standard deviation
• so, use large number of readings to allow outliers to be identified with greater certainty