Homework 2.docx - BIOL 240W: FUNCTION AND DEVELOPMENT OF...

BIOL 240W: FUNCTION AND DEVELOPMENT OF ORGANISMS
Homework Set #2: Using Bar Graphs to Interpret Data
Spring 2022 Buckley
HW #2: Nature vs. Nurture: Why are Leaves from Northern Red Maples “Toothier” Than Leaves
from Southern Red Maples?
Not all leaves of the red maple ( Acer rubrum ) are the same. The “teeth” along the margins of leaves
growing in northern locations differ in size and number from those of their southern counterparts. Are
these differences due to genetic differences between northern and southern Acer rubrum populations, or
do they arise from environmental differences between northern and southern locations, such as average
temperature, that affect gene expression?
Royer, D.L. et al . (2009) performed an experiment in which seeds of Acer rubrum were collected from
four latitudinally distinct sites: Ontario (Canada), Pennsylvania, South Carolina and Florida. The seeds
from the four sites were then grown in a northern location (Rhode Island) and a southern location
(Florida). After a few years of growth, leaves were harvested from the four sets of plants growing in the
two locations.