Discussion
Why Results May Still be Insignificant
The results show a significant p-value (0.13), this means that C.tuberculatus is more likely to leave an area of low algae growth than to stay there. Though the results were found to have a significant p-value (0.13), on a larger scale the same experiment may be insignificant.
The sample size of four tide pools over the span of three days is too short a study for results to be declared significant. In addition the chiton photo counting method is high in human error, leaving further doubt in the significance of the results.
A better experimental design would have at least n=30 tide pools. Chitons would be tagged with b-tags and monitored on a daily basis over a period of three years. (Three years is thought to be the average life span for C.tuberculatus . (Glenn) Though Crozier insists that life span is much longer.) The study would also confirm the location of each chiton home site prior to beginning the experiment.
Analysis in the Context of Significant Results
C.tuberculatus home sites are generally dark crevices in-between rocks or submerged tide pools along rocky coasts. (Glenn) It has been found that C.tuberculatus is photonegative in younger stages and slightly photonegative in older stages. (Glenn) Chitons photo negativity contributes to their choice in home site terrain (Crozier).
Photo negativity appears to account for a significant portion of home site choice.(Crozier) Observational evidence suggests (Factors) other factors/dynamics are significant in determining the home site and areas in which C.tuberculatus frequents.
The natural homochromatic coloration (rock like color) of C.tuberculatus and their calcium carbonate shells ability to sustain algae growth may lead to the assertion that C.tuberculatus are naturally adept in living in both areas of high algae growth and low algae growth. (Crozier) As they are able to blend into either terrain.
The data showed that higher numbers of C.tuberculatus were present in tide pools with high algae growth and stayed in those pools. However it is important to note that three C.tuberculatus out of nine stayed in areas of low algae growth. Essentially 1/3 of the C.tuberculatus counted in the two low algae tide pools stayed in the pool. This data is a curiosity, as it leads to the question, "why does one C.tuberculatus choose to stay in a low algae pool while another C.tuberculatus chooses a high algae pool?". Though this study showed there to be a correlation between C.tuberculatus living in areas of high algae growth vs. low algae growth, it has not explained why they choose to live in one over another.
The researcher feels one reason that C.tuberculatus chooses areas of high algae growth over low would be its closer to its food source. Despite C.tuberculatus leaving their home site to graze at night, from an evolutionary stand point, it would be favorable to stay as close to a food source as possible.
In short the data was found to be significant, and C.tuberculatus tends to stay in areas of high algae growth over low. The significance of the data leads to other questions, such as, "What is the impetus behind C.tuberculatus choice to stay in a low or high algae pool?" and "What is the physiological processes that enables C.tuberculatus to sense if they are in an area of preference?".
Further questions
The following are a list of questions that arose from this experiment:
The results were significant but why, did some chiton stay in the non-algae tide pools over the algae filled tide pools, three were found to have stayed over a three day period? what is the impetus behind this decision? What other factors contribute to tide pools staying in one area over another?
Chitons have been around since the Cambrian era, yet scientist say they have evolved little since then, is this a true assertion? If so what evidence is given to prove this assertion? Fossils? genetic analysis?