College Lesson Plans
The goal of this lesson is to answer the question: Are pikas living at low elevations genetically different than those at high elevations? Students investigate this question in two ways, both commonly used by modern population geneticists. First, students investigate general gene flow in these populations by looking at the proportion of individuals that are heterozygous in a population. Second, they will look at single nucleotide polymorphism (SNP) data to identify DNA regions (loci) that may be undergoing natural selection and will use their creativity to guess possible functions of these genes. Finally, students will develop methods for testing their gene’s function and consider the ability of low elevation pikas to survive in the future.
This activity is based on research to determine if demographic parameters were influencing the genetic diversity of walleye populations. Walleye are nocturnal top predators in many North America lakes. They are also highly sought after sport fish so they are closely monitored and heavily stocked. With this in mind, the researchers gathered genetic data from walleye populations with varying demographic characteristics and stocking intensities. The objective was to identify possible correlations between demographic factors, such as population size and sex ratios, with genetic diversity. The genetic diversity data will be given to you since such analysis is outside the scope of this exercise. We will focus on population level heterozygosity (HE) and allelic richness (AR; basically the number of alleles occurring per locus in each population). But you will have to calculate several demographic variables. Next, you’ll assess the influence of stocking on genetic diversity in two ways. First you’ll take a qualitative approach and see if genetic diversity different between three classes of lakes. You’ll do a few summary statistics and make a table and bar graph of your results. Next, we’ll take a more quantitative approach and look at the correlation between stocking intensity and genetic diversity. Finally, you’ll produce a brief write-up interpreting your results and referencing your figures.
Dr. Smith’s burying beetle research has targeted three different sites in the East River Valley: Kettle Ponds, Maxfield Meadow, and Bellview. These sites occur along an altitudinal gradient; as the elevation increases, environmental variables are expected to change in a predictable manner. In this assignment, students will investigate how these changes affect organisms.
Dr. Smith uses ecological census techniques to estimate the size of rodent and beetle populations at her study sites. She sets baited traps, and then captures, marks (hair dye for rodents, pin prick for beetles), and releases organisms. By recording the proportion of marked to unmarked individuals in each sample, Dr. Smith can estimate total population size. In this assignment students will learn more about the mark-recapture method, and how to calculate population estimates using mathematical equations. This new information will help students investigate how populations change over time.
The Sun provides the Earth with an incredible amount of energy. Primary producers convert the light energy into chemical energy, and in this usable form it transfers through entire ecosystems. However, a significant amount of energy is lost at each transfer. In this assignment students will measure the efficiency of energy transfers between rodents and beetles, and investigate how organisms obtain and use matter and energy to live and grow.