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For centuries, biogeographers have examined the factors that produce patterns of biodiversity across regions. The study of islands has proved particularly fruitful and has led to the theory that geographic area and isolation influence species colonization, extinction and speciation such that larger islands have more species and isolated islands have fewer species (that is, positive species-area and negative species-isolation relationships) (1-4). However, experimental tests of this theory have been limited, owing to the difficulty in experimental manipulation of islands at the scales at which speciation and long-distance colonization are relevant (5). Here we have used the human-aided transport of exotic anole lizards among Caribbean islands as such a test at an appropriate scale. In accord with theory, as anole colonizations have increased, islands impoverished in native species have gained the most exotic species, the past influence of speciation on island biogeography has been obscured, and the species-area relationship has strengthened while the species-isolation relationship has weakened. Moreover, anole biogeography increasingly reflects anthropogenic rather than geographic processes. Unlike the island biogeography of the past that was determined by geographic area and isolation, in the Anthropocene--an epoch proposed for the present time interval--island biogeography is dominated by the economic isolation of human populations., The number of species (that is, richness) on islands is theorized to be a function of colonization and in situ speciation that add species, and extinction that subtracts them (1-6). [...]

Charles Darwin's travels on HMS Beagle taught him that islands are an important source of evidence for evolution. Because many islands are young and have relatively few species, evolutionary adaptation and species proliferation are obvious and easy to study. In addition, the geographical isolation of many islands has allowed evolution to take its own course, free of influence from other areas, resulting in unusual faunas and floras, often unlike those found anywhere else. For these reasons, island research provides valuable insights into speciation and adaptive radiation, and into the relative importance of contingency and determinism in evolutionary diversification., When Charles Darwin embarked on his five-year odyssey on HMS Beagle, a Royal Navy surveying ship, he was an inexperienced, 23-year-old gentleman naturalist. He returned as one of the rising [...]

Author(s): Marguerite A. Butler (corresponding author) [1]; Stanley A. Sawyer [2]; Jonathan B. Losos [3, 4] Sexual dimorphism is widespread and substantial throughout the animal world [1, 2]. It is [...]

Author(s): Jonathan B. Losos (corresponding author) [1]; Thomas W. Schoener [2]; David A. Spiller [2] The role of behaviour in evolutionary change has long been debated. On the one hand, [...]

Author(s): Jason J. Kolbe (corresponding author) [1]; Richard E. Glor [1]; Lourdes Rodríguez Schettino [2]; Ada Chamizo Lara [2]; Allan Larson [1]; Jonathan B. Losos [1] A genetic paradox [1, [...]

Author(s): Jonathan B. Losos (corresponding author) [1]; Manuel Leal [2, 7]; Richard E. Glor [1]; Kevin de Queiroz [3]; Paul E. Hertz [4]; Lourdes Rodríguez Schettino [5]; Ada Chamizo Lara [...]

Author(s): Thomas W. Schoener (corresponding author) [1]; David A. Spiller [1]; Jonathan B. Losos [2] There has been considerable research on both top-down effects [1, 2] and on disturbances [3, [...]

Author(s): Jonathan B. Losos [1]; Dolph Schluter [2] Large islands typically have more species than comparable smaller islands. Ecological theories, the most influential being the equilibrium theory of island biogeography [...]

The view that environment has a key impact on the evolution of morphology has been supported by research using populations of the lizard Anolis sagrei. These were introduced onto small islands in the Bahamas from a nearby source. It was found that they quickly differentiated from each other over a period of between 10 and 14 years. It can be ascertained that populations respond quickly to new environmental circumstances. Furthermore, this response has similarities with large-scale patterns seen on macroevolutionary timescales.

The article discusses the study of M. E. Arnegard and colleagues on the evolutionary radiation of elephant fishes in Ivindo basin in Africa and its impact on species diversification. It states that the study undertake the question on the factors that promote diversification. Results revealed that electric-organ discharges (EODs) of the species diverged in early stages of evolutionary radiation. It explains the reasons behind the occurrence of diversification in signal structure.