Question

In a research experiment, a student is analyzing if a certain native amphipod is eating an invasive aquatic plant. A control sample of of the plant is dried and weighed (grams) before being placed in a container with water from the sampling location. For every control, there is another sample ("treatment") of the plant that is dried and weighed and placed in a container with an amphipod and water from the sampling location, so that there is 1 control for every 1 treatment. There are 9 treatments and 9 controls total and the data is taken over 5 days. The data was recorded in the tables attached. I need help/recommendations for analyzing the data to create graphs and show the growth change and trends.

All mass recorded in grams

11/14

	Treatment	Control
1	0.07	0.05
2	0.22	0.18
3	0.15	0.12
4	0.11	0.11
5	0.16	0.16
6	0.09	0.08
7	0.07	0.06
8	0.10	0.08
9	0.18	0.14

11/15

	Treatment	Control
1	0.06	0.05
2	0.20	0.18
3	0.14	0.11
4	0.09	0.11
5	0.16	0.16
6	0.08	0.10
7	0.05	0.07
8	0.09	0.08
9	0.17	0.14

11/16

	Treatment	Control
1	0.05	0.06
2	0.18	0.18
3	0.12	0.11
4	0.08	0.12
5	0.13	0.16
6	0.07	0.11
7	0.05	0.08
8	0.07	0.08
9	0.16	0.14

11/17

	Treatment	Control
1	0.05	0.06
2	0.13	0.19
3	0.12	0.12
4	0.08	0.11
5	0.12	0.17
6	0.06	0.13
7	0.05	0.09
8	0.07	0.08
9	0.15	0.15

11/18

	Treatment	Control
1	0.05	0.07
2	0.12	0.18
3	0.12	0.12
4	0.07	0.12
5	0.11	0.16
6	0.06	0.13
7	0.03	0.07
8	0.06	0.07
9	0.16	0.15

Notes:

I allowed 2-3 hours “starvation” between swapping the amphipods to treatments. Different amphipods were used after the mass was taken.

The water was temperature regulated and constantly filtered to ensure sufficient oxygen flow.

Answer 1

IT is a good experiment Btw.

So, for representing this data in graph form and than analyziing it would be easier also. But even if without it, if you see the mass of mostly all samples (treatment) is generally decreasing from Day 1(11/14) to Day 5 (11/18). Which means that the amphipod is eating the sample. It is again quit clear when you compare this trend of treatment ones with that of the control ones.

There are 2 ways of presenting this data in form of graphs--

1) Make graphs of each Sample no. And corresponding control. For eg. Graph of Treatment 2 and control 2.

Like I have uploaded here. You can do this for all the 9 samples and see there trends separately and clearly.

From the picture attached you can see...there was a overall positive change in mass of control sample or no -ve change ( generally) whereas loss of mass in treatment samples.

2) Another way is to take average(mean) of all the samples of Treatment and control on Day 1 , Day 2 ,day 3 ,Day 4 and Day 5 and show there trend. In this way you can show overall or total mass decrease of all treatment one's ones and compare with the control ones

Please hit THUMSUP if I could help you analyziing this data. :)