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Pinnipeds (seals, sea lions, walruses, and their fossil relatives) are one of the most successful mammalian clades to live in the oceans. Despite a well-resolved molecular phylogeny and a global fossil record, a complete understanding of their macroevolutionary dynamics remains hampered by a lack of formal analyses that combine these 2 rich sources of information. We used a meta-analytic approach to infer the most densely sampled pinniped phylogeny to date (36 recent and 93 fossil taxa) and used phylogenetic paleobiological methods to study their diversification dynamics and biogeographic history. Pinnipeds mostly diversified at constant rates. Walruses, however, experienced rapid turnover in which extinction rates ultimately exceeded speciation rates from 12 to 6 Ma, possibly due to changing sea levels and/or competition with otariids (eared seals). Historical biogeographic analyses, including fossil data, allowed us to confidently identify the North Pacific and the North Atlantic (plus or minus Paratethys) as the ancestral ranges of Otarioidea (eared seals + walrus) and crown phocids (earless seals), respectively. Yet, despite the novel addition of stem pan-pinniped taxa, the region of origin for Pan-Pinnipedia remained ambiguous. These results suggest further avenues of study in pinnipeds and provide a framework for investigating other groups with substantial extinct and extant diversity., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Society for the Study of Evolution (SSE).)

Understanding how and why some groups have become more species-rich than others, and how past biogeography may have shaped their current distribution, are questions that evolutionary biologists have long attempted to answer. We investigated diversification patterns and historical biogeography of a hyperdiverse lineage of Lepidoptera, the geometrid moths, by studying its most species-rich tribe Boarmiini, which comprises ca. 200 genera and ca. known 3000 species. We inferred the evolutionary relationships of Boarmiini based on a dataset of 346 taxa, with up to eight genetic markers under a maximum likelihood approach. The monophyly of Boarmiini is strongly supported. However, the phylogenetic position of many taxa does not agree with current taxonomy, although the monophyly of most major genera within the tribe is supported after minor adjustments. Three genera are synonymized, one new combination is proposed, and four species are placed in incertae sedis within Boarmiini. Our results support the idea of a rapid initial diversification of Boarmiini, which also implies that no major taxonomic subdivisions of the group can currently be proposed. A time-calibrated tree and biogeographical analyses suggest that boarmiines appeared in Laurasia ca. 52 Mya, followed by dispersal events throughout the Australasian, African and Neotropical regions. Most of the transcontinental dispersal events occurred in the Eocene, a period of intense geological activity and rapid climate change. Diversification analyses showed a relatively constant diversification rate for all Boarmiini, except in one clade containing the species-rich genus Cleora. The present work represents a substantial contribution towards understanding the evolutionary origin of Boarmiini moths. Our results, inevitably biased by taxon sampling, highlight the difficulties with working on species-rich groups that have not received much attention outside of Europe. Specifically, poor knowledge of the natural history of geometrids (particularly in tropical clades) limits our ability to identify key innovations underlying the diversification of boarmiines., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

The gekkonid genus Cyrtodactylus is a highly diverse group of lizards (280 + species), which covers an expansive geographic range. Although this genus has been the focus of many taxonomic and molecular systematic studies, species on the Southeast Asian island of Borneo have remained understudied, leading to an unclear evolutionary history with cascading effects on taxonomy and biogeographic inferences. We assembled the most comprehensive multilocus Bornean dataset (one mitochondrial and three nuclear loci) that included 129 novel sequences and representatives from each known Cyrtodactylus species on the island to validate taxonomic status, assess species diversity, and elucidate biogeographic patterns. Our results uncovered a high proportion of cryptic diversity and revealed numerous taxonomic complications, especially within the C. consobrinus, C. malayanus, and C. pubisulcus groups. Comparisons of pairwise genetic distances and a preliminary species delimitation analysis using the Automatic Barcode Gap Discovery (ABGD) method demonstrated that some wide-ranging species on Borneo likely comprise multiple distinct and deeply divergent lineages, each with more restricted distributional ranges. We also tested the prevailing biogeographic hypothesis of a single invasion from Borneo into the Philippines. Our analyses revealed that Philippine taxa were not monophyletic, but were likely derived from multiple separate invasions into the geopolitical areas comprising the Philippines. Although our investigation of Bornean Cyrtodactylus is the most comprehensive to-date, it highlights the need for expanded taxonomic sampling and suggests that our knowledge of the evolutionary history, systematics, and biogeography of Bornean Cyrtodactylus is far from complete., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Fissurellidae are marine gastropods with a worldwide distribution and a rich fossil record. We integrate molecular, geographical and fossil data to reconstruct the fissurellid phylogeny, estimate divergence times and investigate historical routes of oceanic dispersal. With five molecular markers for 143 terminals representing 27 genera, we resolve deep nodes and find that many genera (e.g., Emarginula, Diodora, Fissurella) are not monophyletic and need systematic revision. Several genera classified as Emarginulinae are recovered in Zeidorinae. Future work should prioritize emarginuline genera to improve understanding of ancestral traits and the early evolution of fissurellids. Tree calibration with the fossilized birth-death model indicates that crown fissurellids originated around 175 Ma, and generally resulted in younger ages for the earliest nodes than the node dating approach. Model-based biogeographic reconstruction, supported by fossils, infers an Indo-West Pacific origin, with a westward colonization of new oceans via the Tethys Seaway upon the breakup of Pangea. Western Atlantic clades then served as source for dispersal towards other parts of the globe. As the sister group to all other fissurellids, Rimula is ranked in its own subfamily, Rimulinae stat. nov. New synonyms: Hemitominae syn. nov. of Zeidorinae stat. nov.; Cranopsissyn. nov. of Puncturella; Variegemarginulasyn. nov. of Montfortula., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Premise of the Study: A key question in evolutionary biology is why some clades are more successful by being widespread geographically, biome diverse, or species-rich. To extend understanding of how shifts in area, biomes, and pollinators impact diversification in plants, we examined the relationships of these shifts to diversification across the mega-genus Salvia., Methods: A chronogram was developed from a supermatrix of anchored hybrid enrichment genomic data and targeted sequence data for over 500 of the nearly 1000 Salvia species. Ancestral areas and biomes were reconstructed using BioGeoBEARS. Pollinator guilds were scored, ancestral pollinators determined, shifts in pollinator guilds identified, and rates of pollinator switches compared., Key Results: A well-resolved phylogenetic backbone of Salvia and updated subgeneric designations are presented. Salvia originated in Southwest Asia in the Oligocene and subsequently dispersed worldwide. Biome shifts are frequent from a likely ancestral lineage utilizing broadleaf and/or coniferous forests and/or arid shrublands. None of the four species diversification shifts are correlated to shifts in biomes. Shifts in pollination system are not correlated to species diversification shifts, except for one hummingbird shift that precedes a major shift in diversification near the crown of New World subgen. Calosphace. Multiple reversals back to bee pollination occurred within this hummingbird clade., Conclusions: Salvia diversified extensively in different continents, biomes, and with both bee and bird pollinators. The lack of tight correlation of area, biome, and most pollinator shifts to the four documented species diversification shifts points to other important drivers of speciation in Salvia., (© 2019 Botanical Society of America.)

The family Margaritiferidae encompasses 12 valid species, which are distributed widely but disjunctively in the Northern Hemisphere. A lack of a well resolved and temporally calibrated phylogenetic framework of Margaritiferidae has made it difficult to discuss the evolutionary pattern and process. Phylogenetic relationships between five major clades, which were revealed in earlier studies, remain elusive and unresolved. Lamprotula rochechouartii has long been classified within the family Unionidae based on shell morphology, but our preliminary molecular study on this species made us hypothesize that it has an affinity with margaritiferids. Hence, five loci (COI, 16S, 18S, 28S and histone H3) were used to investigate the phylogenetic position of L. rochechouartii and intra-familial relationships within Margaritiferidae using various partitioning strategies. Moreover, two mitochondrial genomes were newly obtained to further resolve and validate the five-clade relationships within Margaritiferidae in a broad view of Unionoida evolution. Both five-gene and mitogenome datasets strongly advocated treating Lamprotula rochechouartii as Margaritifera rochechouartiicomb. nov. Maximum likelihood and Bayesian inference analyses using partitioned five-gene dataset resulted in various topologies, but five well-supported clades were obtained. The most probable cladistic relationships generated by five-gene dataset analyses were identical to subsequent whole mitogenome analyses except the position of M. monodonta. M. rochechouartii and M. laosensis had a well-supported sister relationship and formed a basal clade splitting from the rest of the family. Based on six reliable fossils, crown age of the extant Margaritiferidae was estimated during the Late Cretaceous at 88.3 Ma (95% HPD = 66.2-117.4). But we hypothesized a much earlier origin of this family due to the Permian stem age (mean = 257 Ma, 95% HPD = 230.0-296.0) and a high extinction rate in the whole order. Biogeographic scenarios supported a Laurasian origin of extant Margaritiferidae during the Late Cretaceous, and suggested that Asian margaritiferids may have had two origins, having either Asia (M. rochechouartii, M. laosensis) or North America (M. dahurica, M. laevis, and M. middendorffi) as ancestral. The newly added Margaritiferidae species M. rochechouartii expands our recognized distribution range of modern margaritiferids. Our results indicate that whole mitogenome sequences can be used to reconstruct robust phylogenetic relationships for freshwater mussels, especially with the help of adding M-type mitogenomes., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Despite their complex evolutionary history and the rich fossil record, the higher level phylogeny and historical biogeography of living turtles have not been investigated in a comprehensive and statistical framework. To tackle these issues, we assembled a large molecular dataset, maximizing both taxonomic and gene sampling. As different models provide alternative biogeographical scenarios, we have explicitly tested such hypotheses in order to reconstruct a robust biogeographical history of Testudines. We scanned publicly available databases for nucleotide sequences and composed a dataset comprising 13 loci for 294 living species of Testudines, which accounts for all living genera and 85% of their extant species diversity. Phylogenetic relationships and species divergence times were estimated using a thorough evaluation of fossil information as calibration priors. We then carried out the analysis of historical biogeography of Testudines in a fully statistical framework. Our study recovered the first large-scale phylogeny of turtles with well-supported relationships following the topology proposed by phylogenomic works. Our dating result consistently indicated that the origin of the main clades, Pleurodira and Cryptodira, occurred in the early Jurassic. The phylogenetic and historical biogeographical inferences permitted us to clarify how geological events affected the evolutionary dynamics of crown turtles. For instance, our analyses support the hypothesis that the breakup of Pangaea would have driven the divergence between the cryptodiran and pleurodiran lineages. The reticulated pattern in the ancestral distribution of the cryptodiran lineage suggests a complex biogeographic history for the clade, which was supposedly related to the complex paleogeographic history of Laurasia. On the other hand, the biogeographical history of Pleurodira indicated a tight correlation with the paleogeography of the Gondwanan landmasses., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The harvestmen genus Calicina is represented by 25 short-range endemic species occurring in the western Sierra Nevada, Transverse and Coast Ranges of California. Our principal aim was to reconstruct the temporal and spatial biogeographic history of this arachnid lineage. We inferred a time-calibrated species tree for 21 of 25 described Calicina species using multiple genes and multilocus coalescent-based methods. This species tree was used as a framework for algorithmic biogeographic and divergence time analyses, and a phylogenetic canonical correlation analysis (CCA) was used to examine the relationship between morphological evolution and environmental variables. Species tree and biogeographic analyses indicate that high-elevation Sierran taxa are early-diverging in Calicina, with subsequent biogeographic "criss-crossing" of lineages from the Sierra Nevada to the Coast Ranges, back to the Sierra Nevada, then back to Coast Ranges. In both the Sierra Nevada and Coast Ranges, distantly-related parapatric lineages essentially never occur in sympatry. CCA reveals that in both the Coast Ranges and the Sierra Nevada, distant phylogenetic relatives evolve convergent morphologies. Our evidence shows that Calicina is clearly dispersal-limited, with an ancient biogeographic history that provides unique insight into the complex geologic evolution of California since the mid-Paleogene., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Founder-event speciation, where a rare jump dispersal event founds a new genetically isolated lineage, has long been considered crucial by many historical biogeographers, but its importance is disputed within the vicariance school. Probabilistic modeling of geographic range evolution creates the potential to test different biogeographical models against data using standard statistical model choice procedures, as long as multiple models are available. I re-implement the Dispersal-Extinction-Cladogenesis (DEC) model of LAGRANGE in the R package BioGeoBEARS, and modify it to create a new model, DEC + J, which adds founder-event speciation, the importance of which is governed by a new free parameter, [Formula: see text]. The identifiability of DEC and DEC + J is tested on data sets simulated under a wide range of macroevolutionary models where geography evolves jointly with lineage birth/death events. The results confirm that DEC and DEC + J are identifiable even though these models ignore the fact that molecular phylogenies are missing many cladogenesis and extinction events. The simulations also indicate that DEC will have substantially increased errors in ancestral range estimation and parameter inference when the true model includes + J. DEC and DEC + J are compared on 13 empirical data sets drawn from studies of island clades. Likelihood-ratio tests indicate that all clades reject DEC, and AICc model weights show large to overwhelming support for DEC + J, for the first time verifying the importance of founder-event speciation in island clades via statistical model choice. Under DEC + J, ancestral nodes are usually estimated to have ranges occupying only one island, rather than the widespread ancestors often favored by DEC. These results indicate that the assumptions of historical biogeography models can have large impacts on inference and require testing and comparison with statistical methods., (© The Author(s) 2014. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

During the radiation of a clade, diversification rates can show temporal patterns such as a speedup or slowdown, which might relate to different ecological and evolutionary mechanisms. The temporal dynamics of diversification of whole clades are often visualised as a lineage-through-time (LTT) plot, which traces the number of reconstructed lineages at different time points. However, clades do not radiate evenly across space and may show different temporal dynamics in different regions. As such, a biogeographic approach is required to more completely understand temporal diversification dynamics. Here, I present a tool to extract temporal diversity information across different biogeographic regions from the output of commonly used ancestral range estimation models implemented in the R package BioGeoBEARS. The lineages through space and time (LTST) plot allows for visualisation of diversification dynamics in different regions, formatted in an accessible way which can be used for further quantitative analysis.

Aim: Almost half of the extant species of Crocodylia (nine genera, sensu Benton & Clark) belong to the genus Crocodylus, which originated in the Miocene. Today, this genus has a circumtropical distribution, with representatives found in Asia, Oceania, Africa and the Neotropics. However, its geographical origin and the historical events behind its rapid diversification and global radiation are still debated. Here, we inferred the evolution of a set of life traits that aid in dispersal and how they influenced the biogeography of Crocodylus. Location: Global. Time period: Cretaceous to the present. Major taxa studied: Crocodylidae. Methods: We estimated biogeographical history on a published phylogeny using probabilistic biogeography models. Next, we identified four life traits likely to promote range expansion and used a trait‐based dispersal model jointly to infer evolution of these traits and their influence on the dispersal of crocodilians. Finally, we used diversification analyses to identify shifts in diversification rates. Results: An Asian origin was reconstructed for Crocodylus. Despite the small size of the phylogeny, statistical model comparison reports substantially improved the model fit of trait‐dependent over trait‐independent dispersal models. In individual tests, the four life traits considered (salt tolerance, large size, large clutches and habitat generalism) appear to be correlated statistically with higher dispersal probabilities. However, the traits are likely to be correlated with each other, and we hypothesize that they all reflect the gradual evolution of a range‐expansion phenotype in early Crocodylus that resulted in increased diversification of the clade. Main conclusions: Increased dispersal in the genus Crocodylus was associated with the gradual evolution of a range‐expansion phenotype. Interestingly, the evolution of the range‐expansion phenotype was also associated with the diversification of the genus in a period of global crocodilian extinction, indicating that range expansion might have served as a potential driver of speciation. This suggests that the concept of "spatial sorting", normally applied at the population genetic level at the leading edge of an expanding population, might also act on a macroevolutionary scale. [ABSTRACT FROM AUTHOR]

The Late Jurassic Tendaguru Formation of Tanzania, southeastern Africa, records a rich sauropod fauna, including the diplodocoids Dicraeosaurus and Tornieria, and the brachiosaurid titanosauriform Giraffatitan. However, the taxonomic affinities of other sympatric sauropod taxa are poorly understood. Here, we critically reassess and redescribe these problematic taxa, and present the largest phylogenetic analysis for sauropods (117 taxa scored for 542 characters) to explore their placement in Eusauropoda. Janenschia robusta has played a prominent role in discussions of titanosaur origins, with various authors referring at least some remains to Titanosauria, a clade otherwise known only from the Cretaceous. Redescription of the holotype of Janenschia, and all referable remains, supports its validity and placement as a non-neosauropod eusauropod. It forms a clade with Haestasaurus from the earliest Cretaceous of the UK, and the Middle/Late Jurassic Chinese sauropod Bellusaurus. Phylogenetic analysis and CT scans of the internal pneumatic tissue structure of Australodocus bohetii tentatively support a non-titanosaurian somphospondylan identification, making it the only known pre-Cretaceous representative of that clade. New information on the internal pneumatic tissue structure of the dorsal vertebrae of the enigmatic Tendaguria tanzaniensis, coupled with a full redescription, results in its novel placement as a turiasaur. Tendaguria is the sister taxon of Moabosaurus, from the Early Cretaceous of North America, and is the first turiasaur recognized from Gondwana. A previously referred caudal sequence cannot be assigned to Janenschia and displays several features that indicate a close relationship with Middle–Late Jurassic East Asian mamenchisaurids. It can be diagnosed by six autapomorphies, so we erect the new taxon Wamweracaudia keranjei gen. et sp. nov. The presence of a mamenchisaurid in the Late Jurassic of southern Gondwana indicates an earlier and more widespread diversification of this clade than previously realized, prior to the geographic isolation of East Asia. Our revised phylogenetic dataset sheds light on the evolutionary history of Eusauropoda, including supporting a basal diplodocoid placement for Haplocanthosaurus, and elucidating the interrelationships of rebbachisaurids. The Tendaguru Formation shares representatives of nearly all sauropod lineages with Middle Jurassic–earliest Cretaceous global faunas, but displays a greater range of diversity than any of those faunas considered individually. Biogeographic analysis indicates that the Tendaguru sauropod fauna was assembled as a result of three main phenomena during the late Early and/or Middle Jurassic: (1) invasions from Euramerica (brachiosaurids, turiasaurs); (2) endemism in west Gondwana (dicraeosaurids, diplodocids); and (3) regional extinctions that restricted the ranges of once widespread groups (mamenchisaurids, the Janenschia lineage). Multiple dispersals across the Central Gondwanan Desert are required to explain the distributions of Jurassic sauropods, suggesting that this geographic feature was at most a filter barrier that became easier to cross during the late Middle Jurassic. [ABSTRACT FROM AUTHOR]

Peat mosses (Sphagnum) hold exceptional importance in the control of global carbon fluxes and climate because of the vast stores of carbon bound up in partially decomposed biomass (peat). This study tests the hypothesis that the early diversification of Sphagnum was in the Northern Hemisphere, with subsequent range expansions to tropical latitudes and the Southern Hemisphere. A phylogenetic analysis of 192 accessions representing the moss class Sphagnopsida based on four plastid loci was conducted in conjunction with biogeographic analyses using BioGeoBEARS to investigate the tempo and mode of geographic range evolution. Analyses support the hypothesis that the major intrageneric clades of peat‐forming species accounting for >90% of peat moss diversity originated and diversified at northern latitudes. The genus underwent multiple range expansions into tropical and Southern Hemisphere regions. Range evolution in peat mosses was most common within latitudinal zones, attesting to the relative difficulty of successfully invading new climate zones. Allopolyploidy in Sphagnum (inferred from microsatellite heterozygosity) does not appear to be biased with regard to geographic region nor intrageneric clade. The inference that Sphagnum diversified in cool‐or cold‐climate regions and repeatedly expanded its range into tropical regions makes the genus an excellent model for studying morphological, physiological, and genomic traits associated with adaptation to warming climates. This study tests the hypothesis that Sphagnum (peat mosses) initially diversified at high latitudes of the Northern Hemisphere and later extended their ranges to tropical and Southern Hemisphere regions. The ancestral geographic area for the genus as a whole is ambiguous, but the four major subgenera, comprising some 90% of the generic species diversity, unambiguously originated at high latitudes. Sphagnum provides a model for research on genomic, ecological, and morphological changes associated with adaptation to warm climates from cold or cool climate ancestors. [ABSTRACT FROM AUTHOR]

The Middle to Late Ordovician was a time of profound biotic diversification, paleoecological change, and major climate shifts. Yet studies examining speciation mechanisms and drivers of dispersal are lacking. In this study, we use Bayesian phylogenetics and maximum likelihood analyses in the R package BioGeoBEARS to reanalyze ten published data matrices of brachiopods and trilobites and produce time-calibrated species-level phylogenetic hypotheses with estimated biogeographic histories. Recovered speciation and biogeographic patterns were examined within four time slices to test for changes in speciation type across major tectonic and paleoclimatic events. Statistical model comparison showed that biogeographic models that incorporate long-distance founder-event speciation best fit the data for most clades, which indicates that this speciation type, along with vicariance and traditional dispersal, were important for Paleozoic benthic invertebrates. Speciation by dispersal was common throughout the study interval, but notably elevated during times of climate change. Vicariance events occurred synchronously among brachiopod and trilobite lineages, indicating that tectonic, climate, and ocean processes affected benthic and planktotrophic larvae similarly. Middle Ordovician inter-oceanic dispersal in trilobite lineages was influenced by surface currents along with volcanic island arcs acting as “stepping stones” between areas, indicating most trilobite species may have had a planktic protaspid stage. These factors also influenced brachiopod dispersal across oceanic basins among Laurentia, Avalonia, and Baltica. These results indicate that gyre spin-up and intensification of surface currents were important dispersal mechanisms during this time. Within Laurentia, surface currents, hurricane tracks, and upwelling zones controlled dispersal among basins. Increased speciation during the Middle Ordovician provides support for climatic facilitators for diversification during the Great Ordovician Biodiversification Event. Similarly, increased speciation in Laurentian brachiopod lineages during the Hirnantian indicates that some taxa experienced speciation in relation to major climate changes. Overall, this study demonstrates the substantial power and potential for likelihood-based methods for elucidating biotic patterns during the history of life. [ABSTRACT FROM AUTHOR]

Aim The tomato family Solanaceae is distributed on all major continents except Antarctica and has its centre of diversity in South America. Its worldwide distribution suggests multiple long-distance dispersals within and between the New and Old Worlds. Here, we apply maximum likelihood ( ML) methods and newly developed biogeographical stochastic mapping ( BSM) to infer the ancestral range of the family and to estimate the frequency of dispersal and vicariance events resulting in its present-day distribution. Location Worldwide. Methods Building on a recently inferred megaphylogeny of Solanaceae, we conducted ML model fitting of a range of biogeographical models with the program 'BioGeo BEARS'. We used the parameters from the best fitting model to estimate ancestral range probabilities and conduct stochastic mapping, from which we estimated the number and type of biogeographical events. Results Our best model supported South America as the ancestral area for the Solanaceae and its major clades. The BSM analyses showed that dispersal events, particularly range expansions, are the principal mode by which members of the family have spread beyond South America. Main conclusions For Solanaceae, South America is not only the family's current centre of diversity but also its ancestral range, and dispersal was the principal driver of range evolution. The most common dispersal patterns involved range expansions from South America into North and Central America, while dispersal in the reverse direction was less common. This directionality may be due to the early build-up of species richness in South America, resulting in large pool of potential migrants. These results demonstrate the utility of BSM not only for estimating ancestral ranges but also in inferring the frequency, direction and timing of biogeographical events in a statistically rigorous framework. [ABSTRACT FROM AUTHOR]

Aim: A prevailing hypothesis for how Pacific islands organisms have obtained their extant distributions is that of a stepping-stone model, in which populations originate from Papua New Guinea in the western Pacific and gradually disperse eastward. Here, we test this model using a spatiotemporal framework for Emoia cyanura and E. impar, two species within the Emoia cyanura species group (ECSG; Family: Scincidae). We further assess species limits within the group, utilizing novel coalescent methods. Location: Pacific Islands. Methods: We obtained DNA sequence data from one mitochondrial and three nuclear markers for 117 individuals, representing seven of the nine species within the ECSG. These data were analysed for concordance with the steppingstone model using estimation of population structure, divergence dates, and historical biogeographical range. To assess hypotheses of independent lineages within each widespread species, we also employed the Bayesian Phylogenetics & Phylogeography (BPP) program to define operational taxonomic units in *BEAST. Results: Population structure analyses consistently found individuals from western island groups representing divergent populations, with central and eastern populations demonstrating minimal genetic variation. Phylogenetic hypotheses support a western origin for E. cyanura and E. impar, while biogeographical and divergence time estimations predict a recent and rapid expansion out of the western Pacific. The BPP and *BEAST analyses found evidence for five independent lineages within E. impar and five independent lineages within E. cyanura/E. pseudocyanura. Main conclusions: In contrast to the expectations of a stepping-stone model, E. cyanura and E. impar each exhibit the genetic signature of a rapid radiation during the mid to late Pleistocene, with evidence for newly identified lineages, mainly on western islands. Of these recovered lineages, we propose three to be elevated to species status. These findings expand our understanding of endemic Pacific biota, which are subject to conservation threats from human impacts and climate change. [ABSTRACT FROM AUTHOR]

Aim: Here, I investigate galagid diversification and current distribution in the context of major climatic and geological events in sub-Saharan Africa. Given their widespread distribution and presence in a large range of diverse habitats, galagids represent an excellent group to investigate the role of forest contraction and expansion on biological diversification in sub-Saharan Africa. Location: Sub-Saharan Africa (Afrotropical Region). Methods: I assembled a supermatrix including 53 nuclear loci and three mitochondrial markers for 94% of the galagid species currently recognized. Bayesian and maximum likelihood methods were used to infer phylogenetic relationships and times of divergence within the family. Ancestral ranges were estimated using several methods, including 'BioGeoBEARS' and rasp. Results: Phylogenetic analyses corroborated previous results regarding the evolutionary history of this family: (1) early origin of the family soon after the Eocene-Oligocene boundary; (2) dwarf galagos (Galagoides spp.) represent a polyphyletic group with two well-defined clades, one in central-west Africa and one in the east; and (3) divergences within galagids are relatively old with most genera already present by the Late Miocene. The biogeographical analysis indicates central African origins and subsequent expansion to the east in the Early- Middle Miocene. An expansion to the northern and southern savannas occurred between the Late Pliocene and the Middle Pleistocene. Main conclusions: The results of this study clarify several questions related to the evolutionary history of the Galagidae in the context of sub-Saharan African biogeography. This study suggests that galagid evolution and diversification was affected by three major climatic episodes: (1) the global cooling and forest contraction in the Early Oligocene, (2) the forest expansion and the uplift of the African rifts in the Miocene and (3) the aridification and extension of open woodlands and savannas in the Late Miocene and Plio-Pleistocene. [ABSTRACT FROM AUTHOR]

Aim The respective contribution of vicariance and/or dispersal events to the evolution of clades dwelling in the archipelagic parts of the Oriental and Australian regions remains equivocal. Using a complete, species-level phylogeny of Polyura butterflies that are widespread in the oriental Palaeotropics, we aim to test predictions related to vicariance driven by past abiotic factors in the Indo-Australian archipelago (IAA) (Miocene tectonics and Pleistocene climatic shifts) versus repeated trans-archipelagic dispersal events. Location The Oriental and Australian regions with a focus on the IAA. Methods Bayesian species tree phylogenetic analyses were conducted using a matrix comprising two mitochondrial and two nuclear gene fragments. Bayesian relaxed clocks were used to produce a chronogram, which was used in ancestral area estimations to infer the spatio-temporal evolution of the genus at different geographical scales. Diversification dynamics were investigated using the package Tree Par in R. Results Polyura originated during the mid-Miocene ( c. 13 million years ago). Ancestral area estimations inferred an origin in Indomalaya. Wallacea was colonized out-of-Indomalaya in the P. pyrrhus group, while the P. athamas and P. eudamippus groups diversified in Indomalaya and the east Palaearctic. We inferred three long-distance dispersal (LDD) events. The first one implies out-of-Sunda colonization of the Solomon Islands, which have three extant, endemic species. The second implies a colonization of Vanuatu out-of-Sunda that later served as a stepping stone for the colonization of other Pacific islands (Fiji and New Caledonia). A third permitted the reverse colonization of Wallacea from the Pacific islands. These LDD events were supported by our diversification analyses that suggested no diversification rate shift throughout the evolution of the genus. Main conclusions Our results suggest unusual colonization routes with Pacific islands as a hub for late Miocene reverse colonizations back into the centre of the Indo-Australian archipelago. [ABSTRACT FROM AUTHOR]

• Detected 4 main lineages originated in the Miocene in the African continent. • Saharo-Sindian lineages evolved separately from Palaearctic and Afrotropical Region. • Oriental Region: colonized after dispersal event from the Afrotropical Region. • The genus Hycleus includes also the genera Ceroctis and Paractenodia. • No subgeneric division was found, but some phenetic groups resulted well supported. Hycleus is a hyper-diverse genus of blister beetles including ~500 species widely distributed in the Old World, currently divided into three "sections" and into 45 "phenetic" species groups according to morphological characters. Recently the monophyly of Hycleus was questioned pointing out its paraphyly with respect to the genera Ceroctis and Paractenodia. In this study, we built a time-calibrated phylogenetic tree based on DNA sequence data from mitochondrial and nuclear genes obtained from 125 species, to understand the phylogenetic relationships among the species of this genus, to infer the biogeographic processes behind their diversification, and to assess their taxonomy and classification. Our results identified four main lineages one of which included the species belonging to Ceroctis and Paractenodia ; therefore, both taxa are now referred to Hycleus as new synonyms. The three described sections of Hycleus resulted polyphyletic and are rejected, whereas several species groups represented well supported clades. Hycleus likely originated in Africa during the Early Miocene (~20 Mya), and subsequently spread in Europe and western Asia. Later, in the Late Miocene (~6 Mya) a Saharo-Sindian group branched off from the Palaearctic lineage, whereas the Oriental Region was colonized following a dispersal event through the Arabian Peninsula from the Afrotropical Region (~5 Mya). [ABSTRACT FROM AUTHOR]