(“Make your own fruit fly” is one of the workshops we are using in the CPD sessions for Primary School teachers. You can download the workshop handout here)
This simple card game is a good way to illustrate the importance of meiosis in the generation of genetic diversity.
The game is based on the Genetics of fruit flies (Drosophila melanogaster), a widely used model organism in biomedical research. Fruit flies have only four pairs of chromosomes (one pair of sex chromosomes -X and Y-, and three pairs of autosomes -2,3,4). Each card represents a chromosome (paternal chromosomes printed in blue card, maternal chromosomes in lilac or pink card). Chromosomes contain genes which will determine how the flies will look like (phenotype). Each card (chromosome) carries either a normal copy (noted by +) or a mutant copy of a gene (noted by the gene name abbreviation). You can find a copy of the template here
– Each student (or pair/group of students) will receive a randomly chosen set of eight colour coded cards corresponding to the four pairs of fly chromosomes: four blue cards (1-4) and four lilac (or pink) cards (1-4).
– They will be aske to “pair the chromosomes”, setting the maternal and paternal copy of each chromosome side by side.
– The students will then write down the gene combinations in the table provided in the handout.
– Using the tables, the students will figure out how their fly will look like (i.e. White or red eyes, normal size wings/eye, etc). Here is an example for the template press here:
Each student (or group) will then use the information from the table to build a model of the fly using the materials provided (playdough, buttons, etc):
– Compare the external characteristics (phenotype) of the starting flies (parental generation) with the flies built by the students. During meiosis genes get “shuffled” like the cards in our game: the result is different each time, and each combination of genes makes an individual UNIQUE. Point out how many different kinds of flies arise from “shuffling” the genes.
– Why is diversity good for the species? Explain what is the evolutionary advantage of genetic diversity.