Abstract
Biodiversity is an incredibly important concept that helps us understand the distribution of life on Earth. Tropical islands are excellent subjects for the study of biodiversity because many of them are considered biodiversity hotspots and their isolation creates a concise area in which to consider fundamental processes of speciation, migration, and extinction. Global comparisons of island systems are not common in the island biogeography literature because of the difficulty associated with gathering and processing the large amount of data needed to make informed conclusions. Here, I present the SSARP R package, which I created to streamline the process of collecting and analyzing global biodiversity data from web databases for the purpose of creating species-area relationships for island-dwelling taxa. Using SSARP, I also determined the impact of non-native species on the species-area relationships of three lizard genera that together inhabit islands across the globe: Anolis, Phelsuma, and Emoia. I created two species-area relationships for each genus, one that included only native species and one that included both native and non-native species, using SSARP and categorized each included occurrence point as native or non-native using the Reptile Database. Non-native species flattened the species-area relationships for Anolis and Phelsuma, but not for Emoia.
Finally, I explored whether the emergence of biodiversity could be predictable using the video game Project Hastur. This video game serves as a perfect testing ground for determining whether the same environmental pressures (in this case, player strategy) lead to predictable evolution as the enemies evolve to combat player strategy. Using a series of experiments with different playing styles and evolutionary treatments, I found that evolution is only predictable in terms of the relative amount of variation produced, but that the details of the varieties that arise differ dramatically even within replicates. These results, along with the varied impact of adding non-native species to species-area relationships, serve as a reminder that the processes contributing to biodiversity are extremely nuanced. Non-native species do not always negatively impact the overall biodiversity of their newfound homes, and the process of evolution is not always predictable even when convergent evolution appears to be the most reasonable expectation.