Established are four microcosms (beakers) to study the simultaneous effects of light and predation on the relative abundance of our ciliate phenotypes. These microcosms will create the following conditions:
1) no predators, no light
2) no predators, with light
3) with predators, no light
4) with predators, with light
The beaker is filled with water. You will inoculate your microcosms by injecting a small volume (1 ml) of a mixed culture of ciliates. Into two of your beakers, you will transfer a single Daphnia. Finally, place your microcosm in the dark or under the full-spectrum light source (depending on which type of microcosm it is to be).
You will then make a wet mount slide to determine the initial relative abundance of each of the ciliate phenotypes in the mixed culture added to your microcosms. Use the microscope and examine several fields of view to determine the relative abundance of each phenotype. Write your observations on the board at the front of the lab. Once everyone has completed this, you will calculate an average initial relative abundance (based on all student observations).