Leaf Margin Analysis, Or, Are Leaves Good Predictors of Climate?
Objectives: The purpose of this lab is to: • test models for estimating mean annual temperature (MAT) that are derived from leaf margins • read an analyze a scientific paper • perform chi square tests (2 x 2 contingency table and goodness-of-fit) Introduction: Since plants are stationary they must respond developmentally, and ultimately evolutionarily, to their environment. As a result, it’s not surprising that leaf morphology (shape) has been shown to be related to climate. For example, some the following correlations have been reported (Wiemann et al, 1998): (a) leaf length is directly related to the mean annual temperature (MAT); (b) leaf area is directly correlated to both mean annual precipitation (MAP) and MAT; and (c) leaf width is directly correlated with MAP. Thus, leaves are longer and larger in climates with warmer temperatures and higher rainfall. Another interesting observation that was first reported about 100 year ago is that woody deciduous plants having leaves with too
