Explain considerations in quantitative investigations of variation within a species
● Collect data from random samples→ removes bias
● Use large sample size → representative of whole population
● Ethical sampling→ must not harm organism
● Calculate a mean value of collected data + S.D of mean
● Interpret mean values + their standard deviations
○ S.D shows spread of values about mean → ↑ S.D = ↑ variation
○ S.D overlap, causing values of 2 sets of data to be shared, any difference due to chance / not signif
● Use statistical test → analyse whether there is a sig diff between pops