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The study of islands as model systems has played an important role in the development of evolutionary and ecological theory. The 50th anniversary of MacArthur and Wilson's (December 1963) article, 'An equilibrium theory of insular zoogeography', was a recent milestone for this theme. Since 1963, island systems have provided new insights into the formation of ecological communities. Here, building on such developments, we highlight prospects for research on islands to improve our understanding of the ecology and evolution of communities in general. Throughout, we emphasise how attributes of islands combine to provide unusual research opportunities, the implications of which stretch far beyond islands. Molecular tools and increasing data acquisition now permit reassessment of some fundamental issues that interested MacArthur and Wilson. These include the formation of ecological networks, species abundance distributions, and the contribution of evolution to community assembly. We also extend our prospects to other fields of ecology and evolution -understanding ecosystem functioning, speciation and diversification -frequently employing assets of oceanic islands in inferring the geographic area within which evolution has occurred, and potential barriers to gene flow. Although island-based theory is continually being enriched, incorporating non-equilibrium dynamics is identified as a major challenge for the future.

Habitat loss is a primary threat to biodiversity across the planet, yet contentious debate has ensued on the importance of habitat fragmentation 'per se' (i.e., altered spatial configuration of habitat for a given amount of habitat loss). Based on a review of landscape-scale investigations, Fahrig (2017; Ecological responses to habitat fragmentation per se. Annual Review of Ecology, Evolution, and Systematics 48:1-23) reports that biodiversity responses to habitat fragmentation Highlights  Habitat loss and fragmentation have long been considered to have negative effects on biodiversity, yet recent review by Fahrig (2017) argues that in fact habitat fragmentation has largely positive effects on biodiversity.  We highlight several key shortcomings to the approach taken in Fahrig (2017) that limits conclusions regarding habitat fragmentation effects.  Several sources of counter evidence not considered in Fahrig (2017) illustrate that negative effects of habitat fragmentation are common and that positive effects can be misleading or not of conservation importance.  We provide six key reasons why the conclusions in Fahrig (2017) should not be used in conservation decision-making.

Abstract:Islands acquire species through immigration and speciation. Models