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Rationale and Overview Islands are some of the most beautiful and human-visited ecosystems on the planet. Unfortunately, they are also among the most fragile and endangered, being particularly vulnerable to the impacts of habitat loss, fragmentation, and invasive species. Ecologically, islands have been the inspiration for many novel theories within ecology, and many of these ideas are unique to island ecosystems – such as island biogeography and the taxon cycle. These ideas are typically covered only briefly during introductory ecology courses, and merely as exceptions to more general theories. The goal of the proposed course is to better clarify the historical, current, and future biodiversity impacts as well as the manner in which these fragile and isolated ecosystems are formed. Understanding how the biological diversity of these ecosystems are formed is essential to those who are interested in conserving biodiversity. Misunderstanding how biological diversity is produced and constructed could have serious ecological, legal and ethical consequences if it leads to wrong conservation decisions. All ecosystems are formed as an interaction between geologically ancient historical and more recent ecological forces. Historical biogeographical explanations for the current distribution and abundance of island ecosystems include geographic proximity to mainland ecosystems, order of formation of an island chain, and proximity to jet streams. During this short section, we will also touch on species definitions, speciation, and extinction. Historical biogeography will therefore be introduced primarily as a preliminary mode of inquiry, and one that should be explored before proceeding to the more proximate ecological explanations. The bulk of the course will be focused on the ecological theories and explanations for island biodiversity, including populational changes after a dispersal event, adaptive radiation, the taxon cycle, the equilibrium theory of island biogeography, and metapopulation dynamics among others. Ecological ideas will be discussed that are germane to island ecosystems, although previous knowledge of mainland ecology will be helpful. As such, students would benefit by taking an introductory ecology course before taking the proposed course. These theoretical approaches will be applied to real-world conservation issues during the last two weeks of the course. We will focus on the two human-caused impacts that are responsible for most extinction and habitat alteration: habitat fragmentation and invasive species. Together, these two factors have changed nearly all inhabited islands from their original state. Students will work to create realistic solutions to problems facing an island ecosystem of their choice during this module. |