The copepod family Centropagidae is widely distributed and occurs in marine, estuarine, freshwater, and inland saline settings. Molecular phylogenies based upon the 16S and 28S genes demonstrate a ...complex biogeographic history, involving at least five independent invasions of continental waters from the sea. The first colonization was ancient, likely into part of Gondwanaland, and resulted in an inland radiation in southern genera via both vicariance and subsequent habitat shifting among different types of continental waters. Species occupying saline lakes are nested within freshwater clades, indicating invasion of these habitats via fresh waters rather than directly from the ocean or from epicontinental seas. In contrast with the great southern clade, all of the remaining continental invasions are northern, species poor, and quite recent, perhaps even Pleistocene. Long-lived evolutionary euryhalinity, a high propensity for inland invasion, continental vicariance, and
in situ radiation within single continents have all played major roles in the diversification of the centropagids.
Subtidal research presents numerous challenges that restrict the ability to answer fundamental ecological questions related to reef systems. These challenges are closely associated with traditional ...monitoring methods and include depth restrictions (e.g. safe diving depths for underwater visual census), habitat destruction (e.g. trawling), mortality of target species (e.g. controlled angling and fish traps), and high operating costs (e.g. remotely operated vehicles and large research vessels). Whereas many of these challenges do not apply or are avoidable in the shallow subtidal environment, the difficulties grow as one attempts to sample deeper benthic habitats. This situation has resulted in a paucity of knowledge on the structure and ecology of deep water reef habitats around the coast of South Africa, and in most marine areas around the world. Furthermore, the inability to effectively survey deep water benthic environments has limited the capacity of researchers to investigate connectivity between shallow and deep water habitats in a standardised and comparable fashion.
Subtidal research presents numerous challenges that restrict the ability to answer fundamental ecological questions related to reef systems. These challenges are closely associated with traditional ...monitoring methods and include depth restrictions (e.g. safe diving depths for underwater visual census), habitat destruction (e.g. trawling), mortality of target species (e.g. controlled angling and fish traps), and high operating costs (e.g. remotely operated vehicles and large research vessels). Whereas many of these challenges do not apply or are avoidable in the shallow subtidal environment, the difficulties grow as one attempts to sample deeper benthic habitats. This situation has resulted in a paucity of knowledge on the structure and ecology of deep water reef habitats around the coast of South Africa, and in most marine areas around the world. Furthermore, the inability to effectively survey deep water benthic environments has limited the capacity of researchers to investigate connectivity between shallow and deep water habitats in a standardised and comparable fashion.
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