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1. Dispersal out of Wallacea spurs diversification of Pteropus flying foxes, the world’s largest bats (Mammalia: Chiroptera)

   https://doi.org/10.1111/jbi.13750  

   Tsang, Susan M. ; Wiantoro, Sigit ; Veluz, Maria Josefa ; Sugita, Norimasa ; Nguyen, Y‐Lan ; Simmons, Nancy B. ; Lohman, David J. ( November 2019 , Journal of Biogeography)

   Islands provide opportunities for isolation and speciation. Many landmasses in the Indo‐Australian Archipelago (IAA) are oceanic islands, and founder‐event speciation is expected to be the predominant form of speciation of volant taxa on these islands. We studied the biogeographic history of flying foxes, a group with many endemic species and a predilection for islands, to test this hypothesis and infer the biogeographic origin of the group.

   Australasia, Indo‐Australian Archipelago, Madagascar, Pacific Islands.

   Pteropus(Pteropodidae).

   To infer the biogeographic history ofPteropus, we sequenced up to 6,169 bp of genetic data from 10 markers and reconstructed a multilocus species tree of 34 currently recognizedPteropusspecies and subspecies with threeAcerodonoutgroups usingBEASTand subsequently estimated ancestral areas using models implemented inBioGeoBEARS.

   Species‐level resolution was occasionally low because of slow rates of molecular evolution and/or recent divergences. Older divergences, however, were more strongly supported and allow the evolutionary history of the group to be inferred. The genus diverged in Wallacea from its common ancestor withAcerodon; founder‐event speciation out of Wallacea was a common inference.Pteropusspecies in Micronesia and the western Indian Ocean were also inferred to result from founder‐event speciation.

   Dispersal between regions of the IAA and the islands found therein fostered diversification ofPteropusthroughout the IAA and beyond. Dispersal inPteropusis far higher than in most other volant taxa studied to date, highlighting the importance of inter‐island movement in the biogeographic history of this large clade of large bats.

    

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2. Biogeography of the Caribbean Cyrtognatha spiders

   https://doi.org/10.1038/s41598-018-36590-y  

   Čandek, Klemen ; Agnarsson, Ingi ; Binford, Greta J. ; Kuntner, Matjaž ( January 2019 , Scientific Reports)

   Island systems provide excellent arenas to test evolutionary hypotheses pertaining to gene flow and diversification of dispersal-limited organisms. Here we focus on an orbweaver spider genusCyrtognatha(Tetragnathidae) from the Caribbean, with the aims to reconstruct its evolutionary history, examine its biogeographic history in the archipelago, and to estimate the timing and route of Caribbean colonization. Specifically, we test ifCyrtognathabiogeographic history is consistent with an ancient vicariant scenario (the GAARlandia landbridge hypothesis) or overwater dispersal. We reconstructed a species level phylogeny based on one mitochondrial (COI) and one nuclear (28S) marker. We then used this topology to constrain a time-calibrated mtDNA phylogeny, for subsequent biogeographical analyses in BioGeoBEARS of over 100 originally sampledCyrtognathaindividuals, using models with and without a founder event parameter. Our results suggest a radiation of CaribbeanCyrtognatha, containing 11 to 14 species that are exclusively single island endemics. Although biogeographic reconstructions cannot refute a vicariant origin of the Caribbean clade, possibly an artifact of sparse outgroup availability, they indicate timing of colonization that is much too recent for GAARlandia to have played a role. Instead, an overwater colonization to the Caribbean in mid-Miocene better explains the data. From Hispaniola,Cyrtognathasubsequently dispersed to, and diversified on, the other islands of the Greater, and Lesser Antilles. Within the constraints of our island system and data, a model that omits the founder event parameter from biogeographic analysis is less suitable than the equivalent model with a founder event.

    

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3. Local endemism and within‐island diversification of shrews illustrate the importance of speciation in building Sundaland mammal diversity

   https://doi.org/10.1111/mec.13820  

   Demos, Terrence_C ; Achmadi, Anang_S ; Giarla, Thomas_C ; Handika, Heru ; Maharadatunkamsi ; Rowe, Kevin_C ; Esselstyn, Jacob_A ( September 2016 , Molecular Ecology)

   Island systems are important models for evolutionary biology because they provide convenient, discrete biogeographic units of study. Continental islands with a history of intermittent dry land connections confound the discrete definitions of islands and have led zoologists to predict (i) little differentiation of terrestrial organisms among continental shelf islands and (ii) extinction, rather than speciation, to be the main cause of differences in community composition among islands. However, few continental island systems have been subjected to well‐sampled phylogeographic studies, leaving these biogeographic assumptions of connectivity largely untested. We analysed nine unlinked loci from shrews of the genusCrocidurafrom seven mountains and two lowland localities on the Sundaic continental shelf islands of Sumatra and Java. Coalescent species delimitation strongly supported all currently recognizedCrociduraspecies from Sumatra (six species) and Java (five species), as well as one undescribed species endemic to each island. We find that nearly all species ofCrocidurain the region are endemic to a single island and several of these have their closest relative(s) on the same island. Intra‐island genetic divergence among allopatric, conspecific populations is often substantial, perhaps indicating species‐level diversity remains underestimated. One recent (Pleistocene) speciation event generated two morphologically distinct, syntopic species on Java, further highlighting the prevalence of within‐island diversification. Our results suggest that both between‐ and within‐island speciation processes generated local endemism in Sundaland, supplementing the traditional view that the region's fauna is relictual and primarily governed by extinction.

    

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4. Phylotranscriptomics Shed Light on Intrageneric Relationships and Historical Biogeography of Ceratozamia (Cycadales)

   https://doi.org/10.3390/plants12030478  

   Habib, Sadaf ; Gong, Yiqing ; Dong, Shanshan ; Lindstrom, Anders ; Stevenson, Dennis William ; Wu, Hong ; Zhang, Shouzhou ( February 2023 , Plants)

   Ceratozamia Brongn. is one of the species-rich genera of Cycadales comprising 38 species that are mainly distributed in Mexico, with a few species reported from neighboring regions. Phylogenetic relationships within the genus need detailed investigation based on extensive datasets and reliable systematic approaches. Therefore, we used 30 of the known 38 species to reconstruct the phylogeny based on transcriptome data of 3954 single-copy nuclear genes (SCGs) via coalescent and concatenated approaches and three comparative datasets (nt/nt12/aa). Based on all these methods, Ceratozamia is divided into six phylogenetic subclades within three major clades. There were a few discrepancies regarding phylogenetic position of some species within these subclades. Using these phylogenetic trees, biogeographic history and morphological diversity of the genus are explored. Ceratozamia originated from ancestors in southern Mexico since the mid-Miocene. There is a distinct distribution pattern of species through the Trans-Mexican Volcanic Belt (TMVB), that act as a barrier for the species dispersal at TMVB and its southern and northern part. Limited dispersal events occurred during the late Miocene, and maximum diversification happened during the Pliocene epoch. Our study provides a new insight into phylogenetic relationships, the origin and dispersal routes, and morphological diversity of the genus Ceratozamia. We also explain how past climatic changes affected the diversification of this Mesoamerica-native genus. 

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5. Phylogeny and biogeography of the northern temperate genus Dracocephalum s.l. (Lamiaceae)

   https://doi.org/10.1111/cla.12502  

   Chen, Ya‐Ping ; Turdimatovich, Turginov Orzimat ; Nuraliev, Maxim S. ; Lazarević, Predrag ; Drew, Bryan T. ; Xiang, Chun‐Lei ( March 2022 , Cladistics)

   The northern temperate genusDracocephalumconsists of approximately 70 species mainly distributed in the steppe‐desert biomes of Central and West Asia and the alpine region of the Qinghai‐Tibetan Plateau (QTP). Previous work has shown thatDracocephalumis not monophyletic and might includeHyssopusandLallemantia. This study attempts to clarify the phylogenetic relationships, diversification patterns, and the biogeographical history of the three genera (defined asDracocephalums.l.). Based on a sampling of 66 taxa comprising more than 80% from extant species ofDracocephalums.l., morphological, phylogenetic (maximum parsimony, likelihood, and Bayesian inference based on nuclear ITS and ETS, plastidrpl32‐trnL,trnL‐trnF,ycf1, andycf1‐rps15, and two low‐copy nuclear markersAT3G09060andAT1G09680), molecular dating, diversification, and ancestral range estimation analyses were carried out. Our results demonstrate that bothHyssopusandLallemantiaare embedded withinDracocephalumand nine well‐supported clades can be recognized withinDracocephalums.l. Analyses of divergence times suggest that the genus experienced an early rapid radiation during the middle to late Miocene with major lineages diversifying within a relatively narrow timescale. Ancestral area reconstruction analyses indicate thatDracocephalums.l. originated in Central and West Asia and southern Siberia, and dispersed from Central and West Asia into the QTP and adjacent areas twice independently during the Pliocene. The aridification of the Asian interior possibly promoted the rapid radiation ofDracocephalumwithin this region, and the uplift of the QTP appears to have triggered the dispersal and recent rapid diversification of the genus in the QTP and adjacent regions. Combining molecular phylogenetic and morphological evidence, a revised infrageneric classification ofDracocephalums.l. is proposed, which recognizes nine sections within the genus.

    

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