Of mice and mammoths: generality and antiquity of the island rule

ABSTRACT Aim We assessed the generality of the island rule in a database comprising 1593 populations of insular mammals (439 species, including 63 species of fossil mammals), and tested whether observed patterns differed among taxonomic and functional groups. Location Islands world-wide. Methods We measured museum specimens (fossil mammals) and reviewed the literature to compile a database of insular animal body size (S i = mean mass of individuals from an insular population divided by that of individuals from an ancestral or mainland population, M). We used linear regressions to investigate the relationship between S i and M, and ANCOVA to compare trends among taxonomic and functional groups. Results S i was significantly and negatively related to the mass of the ancestral or mainland population across all mammals and within all orders of extant mammals analysed, and across palaeo-insular (considered separately) mammals as well. Insular body size was significantly smaller for bats and insectivores than for the other orders studied here, but significantly larger for mammals that utilized aquatic prey than for those restricted to terrestrial prey. Main conclusions The island rule appears to be a pervasive pattern, exhibited by mammals from a broad range of orders, functional groups and time periods. There remains, however, much scatter about the general trend; this residual variation may be highly informative as it appears consistent with differences among species, islands and environmental characteristics hypothesized to influence body size evolution in general. The more pronounced gigantism and dwarfism of palaeo-insular mammals, in particular, is consistent with a hypothesis that emphasizes the importance of ecological interactions (time in isolation from mammalian predators and competitors was 0.1 to > 1.0 Myr for palaeo-insular mammals, but < 0.01 Myr for extant populations of insular mammals). While ecological displacement may be a major force driving diversification in body size in high-diversity biotas, ecological release in species-poor biotas often results in the convergence of insular mammals on the size of intermediate but absent species

Dwarf deer of Crete.

26 pages : illustrations (some color), map ; 26 cm.Age-graded fossils of Pleistocene endemic Cretan deer (Candiacervus spp.) reveal unexpectedly high juvenile mortality similar to that reported for extant mainland ruminants, despite the fact that these deer lived in a predator-free environment and became extinct before any plausible date for human arrival. Age profiles show that deer surviving past the fawn stage were relatively long-lived for ruminants, indicating that high juvenile mortality was not an expression of their living a "fast" life. Although the effects on survivorship of such variables as fatal accidents, starvation, and disease are difficult to gauge in extinct taxa, the presence of extreme morphological variability within nominal species/ecomorphs of Candiacervus is consistent with the view that high juvenile mortality can function as a key innovation permitting rapid adaptation in insular contexts

The species-area relationship: new challenges for an old pattern

The species-area relationship (i.e., the relationship between area and the number of species found in that area) is one of longest and most frequently studied patterns in nature. Yet there remain some important and interesting questions on the nature of this relationship, its causality, quantification and application for both ecologists and conservation biologists.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

What story does geographic separation of insular bats tell? A case study on Sardinian Rhinolophids [Correction]

There is an error in the legend of Figure 3. Please see the correct Figure 3 legend here

The unifying, fundamental principles of biogeography: understanding Island Life

I describe the set of fundamental principles of biogeography that can serve as an integrative, conceptual framework for unifying and advancing our abilities to explain the geography of life – generally.  I assert that patterns of variation of biotas among regions and across geographic gradients result from the very regular patterns of variation in environmental conditions across the geographic template. This happens through the influence of that variation on the fundamental biogeographic processes (immigration, extinction and evolution), the influence of those fundamental processes on each other, and ecological feedback in the form of interspecific interactions, which influence the fundamental capacities of other species to immigrate, survive and evolve.  I then summarize principal patterns and current theory in island biogeography within the context of the fundamental, unifying principles and show how they can inform a more integrative, conceptual framework for explaining a genuinely comprehensive set of ecological and evolutionary phenomena for insular biotas

The unifying, fundamental principles of biogeography: understanding Island Life

I describe the set of fundamental principles of biogeography that can serve as an integrative, conceptual framework for unifying and advancing our abilities to explain the geography of life – generally.  I assert that patterns of variation of biotas among regions and across geographic gradients result from the very regular patterns of variation in environmental conditions across the geographic template. This happens through the influence of that variation on the fundamental biogeographic processes (immigration, extinction and evolution), the influence of those fundamental processes on each other, and ecological feedback in the form of interspecific interactions, which influence the fundamental capacities of other species to immigrate, survive and evolve.  I then summarize principal patterns and current theory in island biogeography within the context of the fundamental, unifying principles and show how they can inform a more integrative, conceptual framework for explaining a genuinely comprehensive set of ecological and evolutionary phenomena for insular biotas