Jolene Pappas

# Biodiversity

Updated: Feb 27, 2020

The biodiversity simulation is very simple to use. Each time the user clicks on the "Produce Community" button, a biological community is generated. Up to 11 different species may populate the ecosystem. Some species are more likely to be present and each species has a different range of possible population sizes. Random number generation is used to assign if the species is present for that run and if so, what its population will be.

Teachers can approach using this lab in a variety of ways to practice quantifying biodiversity. Because each run of the simulation is different, students will each get different data. Unlike a real-word scenario, it is relatively easy to identify and count each of the animals in this digital ecosystem. To help students understand the difficulties of collecting real diversity data, a follow up activity could take place in the field once students are familiar with the quantification process the teacher chooses.

There are three provided worksheets that each use a different method of quantifying biodiversity; basic species richness, Margalef's richness index, and Simpson's Diversity Index. Measuring biodiversity can be complex so there are other methods of approaching this as well. Determining richness involves counting the number of different species. Species richness is not the same as diversity, which also accounts more for the population size of each species. While diversity index calculations gives a more complete picture, species richness is a start to understanding the concept of biodiversity, particularly for younger students.

Simpson's is a fairly straightforward approach that generally works for a high school level. The variables used to calculate Simpson's index are the population size of each species and the total number of organisms. More complex methods of estimating biodiversity may take into account additional aspects, such as the roles of species within an ecosystem or even genetic variation within species.

For the provided virtual lab assignments, students compare two communities. In the scenario presented, the two communities exist in different time periods. Depending on the version used, students calculate the richness or diversity index and describe a situation that would lead to any observed changes in the diversity over time. For younger students who may not have the numerical background to fully grasp the quantification, they can still describe general changes in biodiversity between two time periods with counting the different species for a basic representation of species richness.