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Marine provinces, founded on contrasting floras or faunas, have been recognized for more than 150 years but were not consistently defined by endemism until 1974. At that time, provinces were based on at least a 10% endemism and nested within biogeographic regions that covered large geographic areas with contrasting biotic characteristics. Over time, some minor adjustments were made but the overall arrangement remained essentially unaltered. In many provinces, data on endemism were still not available, or were available only for the most widely studied vertebrates (fishes), a problem that is ongoing. In this report we propose a realignment for three reasons. First, recent works have provided new information to modify or redefine the various divisions and to describe new ones, including the Mid‐Atlantic Ridge, Southern Ocean, Tropical East Pacific and Northeast Pacific. Second, phylogeographic studies have demonstrated genetic subdivisions within and between species that generally corroborated provinces based on taxonomic partitions, with a notable exception at the Indian–Pacific oceanic boundary. Third, the original separation of the warm‐temperate provinces from the adjoining tropical ones has distracted from their close phylogenetic relationships. Here we propose uniting warm‐temperate and tropical regions into a single warm region within each ocean basin, while still recognizing provinces within the warm‐temperate and tropical zones. These biogeographic subdivisions are based primarily on fish distribution but utilize other marine groups for comparison. They are intended to demonstrate the evolutionary relationships of the living marine biota, and to serve as a framework for the establishment of smaller ecological units in a conservation context.

Aim To present an up to date account of the Mesozoic history of India and its relationship to the other Gondwana continents and to Eurasia.Location Continents surrounding the Western Indian Ocean.Methods Utilization of recent evidence of continental relationships based upon research in stratigraphy, palaeomagnetism, palaeontology, and contemporary biotas. ResultsThe physical data revealed a sequence of events as India moved northward: (1) India-Madagascar rifted from east Africa 158-160 Ma (million years ago), (2) India-Madagascar from Antarctica c. 130 Ma, (3) India-Seychelles from Madagascar 84-96 Ma, (4) India from Seychelles 65 Ma, (5) India began collision with Eurasia 55-65 Ma and (6) final suturing took place c. 42-55 Ma. However, data from fossil and contemporary faunas indicate that, throughout the late Cretaceous, India maintained exchanges with adjacent lands. There is an absence in the fossil record of peculiar animals and plants that should have evolved, had India undergone an extended period of isolation just before its contact with Eurasia.Main conclusions The depiction of India in late Cretaceous as an isolated continent is in error. Most global palaeomaps, including the most recent one, show India, as it moves northward, following a track far out in the Indian Ocean. But the evidence now indicates that India's journey into northern latitudes cannot have taken place under such isolated circumstances. Although real breaks among the lands were indicated by the physical data, faunal links were maintained by vagile animals that were able to surmount minor marine barriers. India, during its northward journey, remained close to Africa and Madagascar even as it began to contact Eurasia.

Understanding how geography, oceanography, and climate have ultimately shaped marine biodiversity requires aligning the distributions of genetic diversity across multiple taxa. Here, we examine phylogeographic partitions in the sea against a backdrop of biogeographic provinces defined by taxonomy, endemism, and species composition. The taxonomic identities used to define biogeographic provinces are routinely accompanied by diagnostic genetic differences between sister species, indicating interspecific concordance between biogeography and phylogeography. In cases where individual species are distributed across two or more biogeographic provinces, shifts in genotype frequencies often align with biogeographic boundaries, providing intraspecific concordance between biogeography and phylogeography. Here, we provide examples of comparative phylogeography from (i) tropical seas that host the highest marine biodiversity, (ii) temperate seas with high productivity but volatile coastlines, (iii) migratory marine fauna, and (iv) plankton that are the most abundant eukaryotes on earth. Tropical and temperate zones both show impacts of glacial cycles, the former primarily through changing sea levels, and the latter through coastal habitat disruption. The general concordance between biogeography and phylogeography indicates that the population-level genetic divergences observed between provinces are a starting point for macroevolutionary divergences between species. However, isolation between provinces does not account for all marine biodiversity; the remainder arises through alternative pathways, such as ecological speciation and parapatric (semiisolated) divergences within provinces and biodiversity hotspots.biogeography | coral reefs | evolution | marine biodiversity | speciation P hylogeography has roots in biogeography, wherein geographic provinces are identified by concordant shifts in species composition. If the partitions defined by taxonomy are regarded as first-order approximations of evolutionary genetic separations, then continuity between biogeography and phylogeography is apparent. Marine biogeography, the study of species' distributions and evolutionary processes in the sea, began in the mid19th century based on taxonomic distinctions. Dana (1) divided the surface waters of the world into several temperature zones based on the distributions of corals and crustaceans. Woodward (2) identified a series of marine provinces based on the distributions of mollusks. Forbes (3) made three enduring observations: (i) each biogeographic province is a center of origin for new species, (ii) these new species tend to migrate outward from the center of origin, and (iii) provinces, like species, must be traced back to their historical origins to be understood. These three fundamental contributions appeared in the same decade in which Darwin and Wallace (4) and Darwin (5) identified geography and natural selection as agents of evolutionary change.It is remarkable that five essential publications in the 1850s (1-5) set the stage ...

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