Pokecology: A lesson using Simpson’s Diversity Index
Pokemon is an incredibly expansive world spanning over twenty years and I’ve lost track of how many games (30? 40?) but also one which catches the attention of learners of all ages. With the new games having come out just this November, it seems like a great opportunity to take Pokémon and co-opt it to explore a natural phenomenon. The big question though, is which one? With the games being so incredibly broad there are any number of topics one could explore including everything from geology (don’t tell me that rock types can’t be classed as metamorphic, sedimentary or igneous) to astronomy (there’s got to be something in Sun and Moon). So what do we tackle?
Well...whatever is explored should make use of the game to collect data so participants feel like they are playing but also getting something out of it. The activity should also be something that can be done both within Pokémon and the real world as well as in any Pokémon game. My result? Ecology!
All this activity requires is a Pokémon game-- we used Let’s Go Eevee but any game will work-- something that can be used to record data and a method for calculations (a cell phone, calculator or even laptop will work). And that’s it. You can additionally provide the attached worksheet if desired. With these materials gathered, we move onto a discussion.
Prior to beginning the game, it’s important to establish the goals of collecting as well as the types of ecosystems to be explored and how many Pokémon are going to be sampled. Given the math involved, this is an activity that typically works best with middle schoolers and older, though younger learners might be able to collect data for an older learner or adult to compute. The main tenets of the discussion should be:
Define ecosystem--an area in which the living and non-living things are working together. Living things would include Pokémon and plants whereas non-living things might include water or the sun. This can be tricky in the cave areas because of the rock-types.
Identify the ecosystem to be studied-- there are many types of ecosystems such as aquatic or water based ones and grassland ecosystems. Note: I would avoid the caves because rock-types make it challenging to define living and non-living components.
Identify the boundaries of the ecosystem-- Does a grassland only include a certain number of squares or is it a specific patch of grass? Are you exploring open water or a bounded coast?
Decide on the number of areas to be sampled-- this may be a whole group activity where each learner samples one section or each group may be responsible for multiple sections. A good number for comparison is 3 different examples of one ecosystem to be sampled
Decide on a samplic metric-- are you going to catch all of the Pokémon counted, run into them or observe them by eye? What defines a Pokémon as having been sampled?
Review Relative Abundance (a comparable measure of how rare or common a Pokémon is) and how to calculate it (divide the number of a specific type of Pokémon sampled by the total number of Pokémo of all types sampled)
Review Simpson’s Diversity Index (a measure of diversity or the different number of Pokémon types present. This is a value between 0 and 1 where 1 is very diverse and 0 is not diverse) and how to calculate it:
n = the total number of organisms of a particular species
N = the total number of organisms of all species
This equation means that for each pokémon sampled you count the number encountered and then multiply this number by itself minus 1 and then add this to the same calculated value for each type found. After adding these numbers together, you then divide them by the total number caught times this value minus 1 and subtract the resulting number from one. For example, if you sampled 3 PIdgey and 4 Glooms this value would be calculated by:
1- (3 * (3-1) + 4 * (4-1) / 7 * (7-1) )
Provide learners time to collect data and calculate both relative abundances and Simpson’s Diversity Index for the areas for which they are responsible following the agreed upon sampling rules. If each member is doing one area and comparing, this time could also be used to compare results.
Create a chart comparing calculated relative abundances and Diversity Indexes and discuss results. Some questions to answer might included:
Were any Diversity Index values less than .5 or greater than .5? What might this mean? (areas with a value less than .5 are generally not considered to be very diverse which may be due to a number of reasons including: pollution, human interference, complications due to trainer level (which might result in larger number of low level Pokémon being encountered), or other factors)
Were any areas surprisingly diverse?
Did any areas have the same Diversity Index? What might that mean?
Is there a relationship between relative abundance and Diversity Index? (Areas with Pokémon with high relative abundances might have a lower diversity index and this might imply a lower diversity.)