Activity 2.3 Island Biogeography Simulation Report

 1.0 Introduction

In the biography article, it starts off explaining exactly what biodiversity is. Biogeography is the variety of species and ecosystems in a time or space (2017). This article also suggests development of species over a span of time. “Ecological biogeography refers to the study of the contributing factors for the global distribution of plant and animal species.” is a quote from the bio dictionary. Points out the smaller factors in ecological studies. Some of these factors we explored and our experiments such as size, distance, mortality, and migration rates. In these trials, I got to either confirm or understand better which of these factors changed the data. 

2.0 Data Collection and Analysis

When I first started running the simulation, there were no changes made to the islands. This was to set up some sort of control or comparison to set up a norm. Since there was no manipulation of the second trial, the data show a baseline to compare to. The average of both are exactly the same straight across. I have 9.5 for the mean total of species. I almost wish it would’ve put the island Origen in the mid region, rather than starting it at the largest setting. 

The point of manipulating these islands was to discover which aspects had an effect on the populations. There were two identical Islands to start off with, then manipulated the distance of island 2 to see if it had an effect on the population. I move my island #2 100 KM further away putting it at 110 KM away from the mainland.The data confirms distance does not have a strong connection to populations.The data does not show the species having any advantages over the other based on distance from the mainland.

 In another trial the change was size. island 2 size to 64km making island 2 192 km smaller than island 1. island one as a control and changing island two’s size. Since island one was at the largest possible setting island to was shrunk limiting the number of species. The total of both of the island one’s  trails were 34 and 31. Island two’s totals were both 3. There was a very obvious effect species differentiation when testing size. 

 Then in the third set of trials islands, one and two, we’re both changed in size and distance from the mainland. To see if distance or size, would balance out the results. Island number one was set to a distance of 210 km and size of 256km. Island number two was set at a distance of 70 km and size of 192 km. They did not balance each other out, but wanted to be sure through this trail. The distance did not have a significant effect on the species. The totals of the bigger island still did better than the smaller island even with distant changes. Looking off of the totals of the islands the bigger island still did better than the smaller island even with distant changes.

Then moving onto the last set of trials ran showing how mortality and migration rates affect the number of species. The current number of species never surpassed 10 in the trails even when the migration rate was higher. I wish I would have seen a bigger difference between mortality rates as well as migration rates. While island number two was slightly smaller. The immigration rate increased, but the numbers did not increase in my trials. I almost wish the numbers were reset instead of bringing the same measurements from the fourth set of trials. 

3.0 Discussion

The data relating to distance I found no definitive influence on my trial islands. I was curious if this was due to the species I was studying being airborne.  In the article area and distance there species are snakes(2019). I am intrigued to say the species being airborne had no effect on whether distance had an effect on the data. This other article mentions snakes, and I would assume other ways of migrating and other species. Soon into reading the article, their studies also found smaller square footage had lower diversity in species. I had concluded in my less invasive study distance did not have a strong control over species variation if any, and this article concludes with the results “Distance itself was not important in explaining species richness variation” which I find comforting, knowing I did my experiment correctly (2019). A certain area of land can only accommodate a certain amount of life. The mortality rate on the last trial was combated by the migration rate in my trials. I like to think some of the factors of the mortality rate would, sadly, be caused by humans. I found another article  pertaining to the growth and mortality of diversity. Effects of diversity in 2018 starts to give me examples of why the mortality rate may go up or down, such as droughts. Overall the most interesting out of the trails was the distance. If I were to hypothesize, if the distance away from the mainland would affect the species number I would assume it would. But after seeing the trials, I know that distance has no effect. 

4.0 References

Biologydictionary.net Editors. "Biogeography." Biology Dictionary, Biologydictionary.net, 05 May. 2017, https://biologydictionary.net/biogeography/.

Hutchison, C., Gravel, D., Guichard, F., & Potvin, C. (2018, October 18). Effect of diversity on growth, mortality, and loss of resilience to extreme climate events in a tropical planted forest experiment. Scientific reports. Retrieved February 13, 2023, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6193960/

Portillo, J. T. da M., Ouchi-Melo, L. S., Crivellari, L. B., de Oliveira, T. A. L., Sawaya, R. J., & Duarte, L. da S. (2019, March 14). Area and distance from mainland affect in different ways richness and phylogenetic diversity of snakes in Atlantic Forest Coastal Islands. Ecology and evolution. Retrieved February 13, 2023, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6468059/