Correlation and Causation in Biological Systems with Applications to Asymmetry

 

Owen, R. E.

Tested Studies in Laboratory Teaching, 2010, Volume 31

Abstract

Significant correlations between variables in biological systems often occur. However correlation does not imply direct causation as most associations arise through multiple interactions. Students will be introduced to correlation and be able to calculate simple and partial correlation coefficients. They will understand how to distinguish between conspicuous, directional and fluctuating asymmetry. They will gather data on (1) Fiddler Crabs where they will make hypotheses about the correlation between body size and large and small cheliped size in males, and (2) human total fingerprint ridge counts and use an index based on the correlation coefficient to test for fluctuating asymmetry.

Keywords:  correlation coefficient, asymmetry, bumble bees, human fingerprints, fiddler crabs

University of Delaware (2009)