Ecology Abstract Phillip Tran 10591758 TA Faiza Section 116 The Effect of Number Didinium A proteus on the Population of Paramecium P Caudatum One way we can study ecology is using the top down and bottom up method The top down control is the higher trophic levels on the food chain which is usually controlled by the predators The bottom up control is the lower trophic levels of the food chain which is usually the producers or preys In this experiment we looked at Didinium predator and Paramecium prey For our experiment we wanted to see if the number of Didinium would affect the number of Paramecium but the controlled variable is that in certain trays we have a low population of Didinium and certain trays have a high population Our hypothesis is that the high number of Didinium in a dish the lower the density population of Paramecium Even if there is a difference in population we asked is there a significant difference in the prey density between the low vs high predator population For our method we had different containers for the high vs low predator population and had four dishes with four DidInium and four dishes with two DidInium We added one seed into each dish so there is nutrient for both species and all had similar environments and this experiment ran for a week For our result we concluded that in general the more Didinium in a container the more Paramecium there was In overall aspect there is not a significant difference between the low population vs high population of Didinium Affect of Paramecium on High vs Low Population of Didinium Citations Fronhofer EA Legrand Bottom top down control dispersal major biorxiv Bottom top down control dispersal major 4500 4000 3500 3000 2500 2000 1500 1000 500 0 m u t a d u a C P f o n o ti a u p o P l D up and of across up and of across High Low High and Low Population of A Proteus Figure 1 There is no significant difference in the population of P Caudatum when there is a high vs low population of A Proteus t 11 57 p 0 03 df 21 Series1 organismal groups a coordinated distributed experiment 2017 Nov 2 Banerji A Duncan AB Griffin JS Density and trait mediated effects of a parasite and a predator in a tri tophic food web Shibboleth authentication request 2015 May