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The Oriental fruit flyBactrocera dorsalis(Hendel), a global pest that can decimate regional fruit industries and elicit international quarantines, has been the subject of considerable taxonomic confusion. Previous phylogenetic work revealed thatB. dorsalisis part of a monophyletic clade containing 12 species. We present restriction site‐associated DNA sequencing (RAD‐seq) genomic data for 2,292 specimens, which unequivocally supports the delimitation of two new species, here described asBactrocera borneoensissp. n.Doorenweerd & San Jose andB. incognitasp. n.Doorenweerd & San Jose. We additionally obtained 1,985 Cytochrome C oxidase I (COI) sequences for a subset of the specimens to see which species can be diagnosed with this mtDNA marker and conclude thatB. dorsalis,B. incognita,B. carambolaeDrew & Hancock,B. raiensisDrew & Hancock,B. occipitalis(Bezzi) andB. kandiensisDrew & Hancock cannot be identified reliably using COI due to introgression—but the newly described speciesB. borneoensiscan be identified using COI. The supposed innocuous speciesB. raiensisdistribution is underestimated in Asia and Africa.Bactrocera kandiensisCOI genotypes occur in African flies, but RAD‐seq data confirm that these areB. dorsaliswith introgressedB. kandiensisCOI. The phylogenomic dataset brings new light to the extent of theB. dorsalis s.l.clade and the morphological and molecular confusion based on COI. This will have ramifications for ecological data—including host and distribution ranges—associated withB. dorsalis s.l.clade species, pest identification protocols and our understanding of the economic importance of the various species in the clade.

 

Abstract Adaptive radiation plays a fundamental role in our understanding of the evolutionary process. However, the concept has provoked strong and differing opinions concerning its definition and nature among researchers studying a wide diversity of systems. Here, we take a broad view of what constitutes an adaptive radiation, and seek to find commonalities among disparate examples, ranging from plants to invertebrate and vertebrate animals, and remote islands to lakes and continents, to better understand processes shared across adaptive radiations. We surveyed many groups to evaluate factors considered important in a large variety of species radiations. In each of these studies, ecological opportunity of some form is identified as a prerequisite for adaptive radiation. However, evolvability, which can be enhanced by hybridization between distantly related species, may play a role in seeding entire radiations. Within radiations, the processes that lead to speciation depend largely on (1) whether the primary drivers of ecological shifts are (a) external to the membership of the radiation itself (mostly divergent or disruptive ecological selection) or (b) due to competition within the radiation membership (interactions among members) subsequent to reproductive isolation in similar environments, and (2) the extent and timing of admixture. These differences translate into different patterns of species accumulation and subsequent patterns of diversity across an adaptive radiation. Adaptive radiations occur in an extraordinary diversity of different ways, and continue to provide rich data for a better understanding of the diversification of life.