High migration rates shape the postglacial history of amphi‐Atlantic bryophytes

Paleontological evidence and current patterns of angiosperm species richness suggest that European biota experienced more severe bottlenecks than North American ones during the last glacial maximum. How well this pattern fits other plant species is less clear. Bryophytes offer a unique opportunity to contrast the impact of the last glacial maximum in North America and Europe because about 60% of the European bryoflora is shared with North America. Here, we use population genetic analyses based on approximate Bayesian computation on eight amphi‐Atlantic species to test the hypothesis that North American populations were less impacted by the last glacial maximum, exhibiting higher levels of genetic diversity than European ones and ultimately serving as a refugium for the postglacial recolonization of Europe. In contrast with this hypothesis, the best‐fit demographic model involved similar patterns of population size contractions, comparable levels of genetic diversity and balanced migration rates between European and North American populations. Our results thus suggest that bryophytes have experienced comparable demographic glacial histories on both sides of the Atlantic. Although a weak, but significant genetic structure was systematically recovered between European and North American populations, evidence for migration from and towards both continents suggests that amphi‐Atlantic bryophyte population may function as a metapopulation network. Reconstructing the biogeographic history of either North American or European bryophyte populations therefore requires a large, trans‐Atlantic geographic framework.     

Approximate Bayesian analysis of Drosophila melanogaster polymorphism data reveals a recent colonization of Southeast Asia

Southeast Asian populations of the fruit fly Drosophila melanogaster differ from ancestral African and derived European populations by several morphological characteristics. It has been argued that this morphological differentiation could be the result of an early colonization of Southeast Asia that predated the migration of D. melanogaster to Europe after the last glacial period (around 10,000 years ago). To investigate the colonization process of Southeast Asia, we collected nucleotide polymorphism data for more than 200 X-linked fragments and 50 autosomal loci from a population of Malaysia. We analyzed this new single nucleotide polymorphism data set jointly with already existing data from an African and a European population by employing an Approximate Bayesian Computation approach. By contrasting different demographic models of these three populations, we do not find any evidence for an early divergence between the African and the Asian populations. Rather, we show that Asian and European populations of D. melanogaster share a non-African most recent common ancestor that existed about 2,500 years ago.     

Geographic pattern of genetic variation in the fox tapeworm Echinococcus multilocularis

Intraspecific genetic variation of Echinococcus multilocularis, the etiologic agent of human alveolar echinococcosis, has been evaluated among 76 geographic isolates from Europe, Asia and North America by using sequence data of mitochondrial and nuclear DNA. Relatively low genetic variation was found only in the mitochondrial DNA sequence consisting of 3 protein-coding genes. Pairwise divergence among the resultant 18 haplotypes ranged from 0.03 to 1.91%. Phylogenetic trees and parsimony network of these haplotypes depicted a geographic division into European, Asian and North American clades, but 1 haplotype from Inner Mongolia was unrelated to other haplotypes. The coexistence of the Asian and North American haplotypes could be seen, particularly on the St. Lawrence Island in the Bering Sea. These data suggest an evolutionary scenario in which distinct parasite populations derived from glacial refugia have been maintained by indigenous host mammals. The nuclear DNA sequence for the immunodominant B cell epitope region of ezrin/radixin/moesin-like protein (elp) was extremely conservative, indicating that the elp antigen is available for immunodiagnosis in any endemic areas.     

Genetic evidence suggests a widespread distribution of native North American populations of reed canarygrass

Reed canarygrass is an important agricultural crop thought to be native to Europe, Asia, and North America. However, it is one of the worst wetland invaders in North American wetlands. The native North American status has been supported by the circumstantial evidence of early botanical records and the dating and location of herbarium specimens. The lack of empirical evidence has left the North American native status of the species in doubt and prevented comparisons between native North American and Eurasian populations of the species. We utilized genetic markers to compare a wide range of European and Asian collections to DNA extracted from 38 early North American herbarium specimens. The genetic data confirm the presence of a distinct population present throughout North America in the early twentieth century, but not present in Europe or Asia, ranging from Alaska, USA to New Brunswick, Canada. These native North American populations of reed canarygrass are likely present throughout Alaska today, as one specimen was collected as recently as 1996, and may still be present in other regions of North America. Future research can utilize this dataset to determine the origin of present-day invasive populations in North American wetlands.     

Mitochondrial DNA reveals a strong phylogeographic structure in the badger across Eurasia

The badger, Meles meles, is a widely distributed mustelid in Eurasia and shows large geographic variability in morphological characters whose evolutionary significance is unclear and needs to be contrasted with molecular data. We sequenced 512 bp of the mitochondrial DNA control region in 115 Eurasian badgers from 21 countries in order to test for the existence of structuring in their phylogeography, to describe the genetic relationships among their populations across its widespread geographic range, and to infer demographic and biogeographic processes. We found that the Eurasian badger is divided into four groups regarding their mitochondrial DNA: Europe, Southwest Asia, North and East Asia, and Japan. This result suggests that the separation of badgers into phylogeographic groups was influenced by cold Pleistocene glacial stages and permafrost boundaries in Eurasia, and by geographic barriers, such as mountains and deserts. Genetic variation within phylogeographic groups based on distances assuming the Tamura-Nei model with rate heterogeneity and invariable sites (d(T-N) range: 3.3-4.2) was much lower than among them (d(T-N) range: 10.7-38.0), and 80% of the variation could be attributed to differences among regions. Spatial analysis of molecular variance (samova), median-joining network, and Mantel test did not detect genetic structuring within any of the phylogeographic groups with the exception of Europe, where 50% of variation was explained by differences among groups of populations. Our data suggest that the European, Southwest Asian, and North and East Asian badgers evolved separately since the end of Pliocene, at the beginnings of glacial ages, whereas Japanese badgers separated from continental Asian badgers during the middle Pleistocene. Endangered badgers from Crete Island, classified as Meles meles arcalus subspecies, were closely related to badgers from Southwest Asia. We also detected sudden demographic growth in European and Southwest Asian badgers that occurred during the Middle Pleistocene.     

Global historical biogeography of hadrosaurid dinosaurs

Hadrosaurids were the most derived ornithopods and amongst the most diverse herbivore dinosaurs during the Late Cretaceous of Europe, Asia, and the two Americas. Here, their biogeographical history is reconstructed using dispersal‐vicariance analysis (DIVA). The results showed that Hadrosauridae originated in North America and soon after dispersed to Asia no later than the Late Santonian. The most recent common ancestor of Saurolophidae (= Saurolophinae + Lambeosaurinae) is inferred to have been widespread in North America and Asia. The split between saurolophines and lambeosaurines occurred in response to vicariance no later than the Late Santonian: the former clade originated in North America, whereas the latter did so in Asia. Saurolophine biogeographical history included a minimum of five dispersal events followed by vicariance. Four of these dispersals were inferred to have occurred from North America to Asia during the Campanian and Early Maastrichtian, whereas a fifth event represented a southward dispersal from North to South America no later than the Late Campanian. The historical biogeography of lambeosaurines was characterized by an early evolution in Asia, with a Campanian dispersal to the European archipelago followed by vicariance. Reconstruction of the ancestral areas for the deepest nodes uniting the more derived lambeosaurines clades (‘hypacrosaurs’, ‘corythosaurs’, and ‘parasaurolophs’) is ambiguous. The split between North American and Asian clades of ‘hypacrosaurs’ and ‘parasaurolophs’ occurred in response to vicariance during the Campanian. The evolutionary history of North American ‘hypacrosaurs’ and ‘parasaurolophs’ was characterized by duplication events. The latter also characterized the Late Campanian ‘corythosaurs’, which remained restricted to North America. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 503–525.     

Phylogeography of northern Dolly Varden Salvelinus malma (Salmoniformes: Salmonidae) from Asia and North America: An analysis based on the mitochondrial DNA genealogy

Spawning in habitats affected by Pleistocene glacial advances over most of its natural range, northern Dolly Varden Salvelinus malma malma typifies Arctic fauna distributed in northeastern Asia and northwestern North America. We reconstructed a genealogy of mtDNA haplotypes from 27 Alaskan and Asian populations to study the influence of historical events on the phylogeography and contemporary population genetic structure. Analysis of molecular variance partitioned most of the mtDNA variability to the intrapopulation component (72.5%) with much reduced differences between populations (21.1%) and regions (6.4%). Similar patterns of variation apparent from hierarchical diversity and nested clade phylogeographical analysis (NCPA) of mtDNA haplotypes identify weak spatial differentiation and low levels of divergence. These findings suggest (1) that demographic history has been influenced by historical range expansions and recent isolation by distance, (2) that present populations from Asia and North America were colonized from one main Beringian Refugium, and (3) that this taxon’s ancestral population probably experienced a bottleneck in the Beringian Refugium during the late Pleistocene (Wisconsin) glacial period. The genealogical and NCPA analyses, and mismatch distribution of S. m. malma mtDNA haplotypes do not confirm the assumptions about presence of the two refugia on the territories of the Beringian Land, in which allopatric S. m. malma ancestral populations evolved, and independent origin of the Sea of Okhotsk populations.     

Mitochondrial DNA analysis reveals Holarctic homogeneity and a distinct Mediterranean lineage in the Golden eagle (Aquila chrysaetos)

The Golden eagle (Aquila chrysaetos) is among the most widespread of the birds of prey, covering basically the whole Palaearctic from Europe and North Africa through Asia and Japan, to the North American continent. Only few studies have addressed the species’ genetic structure and the consequences of its demographic history so far, and none of them has covered larger areas of the distribution range. Our present study aims at closing this gap. Based on 283 samples (mostly feathers collected in the field or from museum collections) across the species’ distribution, but with a focus on Europe, we uncover the phylogeography of the Golden eagle. Results imply a phylogeographic split between mainly Northern Europe, Continental Asia, Japan and North America on the one hand and Central–Southern Europe on the other. The observed pattern is likely to be caused by the Last Ice Age, when the population survived in two reproductively isolated glacial refugia. Repopulation of Northern Europe occurred from a presumed Asian refugium, whereas the Alpine range was probably repopulated from a refugium in the Mediterranean region. In Eastern Europe, the Mediterranean and Alpine region we find a co‐occurrence of both lineages that heavily influences the local genetic diversity. This pattern is unlike that in most other large raptors in which usually a western and an eastern Eurasian lineage have been recovered.     

Molecular phylogenetic analysis of Grifola frondosa (maitake) reveals a species partition separating eastern North American and Asian isolates

A phylogenetic analysis was performed on 51 isolates of the commercially valuable basidiomycete, Grifola frondosa (maitake), using sequences from the Internal Transcribed Spacers and 5.8S region of the nuclear ribosomal DNA (rDNA) and a portion of the β-tubulin gene. The β-tubulin gene provided more than twice as many variable characters as the ITS/5.8S regions. The isolates analyzed comprised 21 from eastern North America, 27 from Asia, one from Europe, and two of unknown geographic origin, one of which was the major US commercial production strain in use. Grifola sordulenta was used as an outgroup. Combined and separate analysis of both genes showed a partition separating Asian versus eastern North American isolates. Bootstrap analysis showed strong support for these clades in the β-tubulin data alone and in the combined data. The major commercial isolate of unknown geographic origin is apparently of Asian descent based on its grouping within the Asian clade. The single European isolate analyzed was distinct from both the eastern North American and Asian clades. These results indicate strong support for a species partition separating eastern North American and Asian isolates of G. frondosa, despite previous studies indicating no morphological distinction between them.     

Phylogeography of field voles (Microtus agrestis) in Eurasia inferred from mitochondrial DNA sequences

In a distribution-wide phylogeographic survey of the field vole (Microtus agrestis), 75 specimens from 56 localities across Eurasia were examined for DNA sequence variation along the whole 1140 base pair (bp) mitochondrial (mt) cytochrome b gene. The species is subdivided into three main mtDNA phylogeographic groups - western, eastern and southern - with largely allopatric distributions. The western phylogeographical group is found in west and central Europe and spread most probably from a glacial refugium in the Carpathians. The eastern group covers a large range from Lithuania to central Asia, and probably originated from a southeast European source (e.g. the southern Urals or the Caucasus). The southern group occupies an area from Portugal to Hungary, with division into two distinct mtDNA sublineages that presumably derive from separate glacial refugia in the Iberian Peninsula. Molecular clock estimates suggest that the western and eastern field vole populations separated during the last glaciation, whereas the southern population dates back 0.5-0.9 Myr. High levels of mtDNA variation indicate relatively large population sizes and subdivisions within phylogeographic groups during the last glaciation. We report a possible new suture zone in east Europe.     

Effects of Pleistocene climatic fluctuations on the phylogeographic and demographic histories of Pacific herring (Clupea pallasii)

We gathered mitochondrial DNA sequences (557 bp from the control region in 935 specimens and 668 bp of the cytochrome b gene in 139 specimens) of Pacific herring collected from 20 nearshore localities spanning the species' extensive range along the North Pacific coastlines of Asia and North America. Haplotype diversity and nucleotide diversity were high, and three major phylogeographic lineages (sequence divergences ca. 1.5%) were detected. Using a variety of phylogenetic methods, coalescent reasoning, and molecular dating interpreted in conjunction with paleoclimatic and physiographic evidence, we infer that the genetic make-up of extant populations of C. pallasii was shaped by Pleistocene environmental impacts on the historical demography of this species. A deep genealogical split that cleanly distinguishes populations in the western vs. eastern North Pacific probably originated as a vicariant separation associated with a glacial cycle that drove the species southward and isolated two ancestral populations in Asia and North America. Another deep genealogical split may have involved either a vicariant isolation of a third herring lineage (perhaps originally in the Gulf of California) or it may have resulted simply from the long coalescent times that are possible in large populations. Coalescent analyses showed that all the three evolutionary lineages of C. pallasii experienced major expansions in their most recent histories after having remained more stable in the preceding periods. Independent of the molecular calibration chosen, populations of C. pallasii appear to have remained stable or grown throughout the periods that covered at least two major glaciations, and probably more.     

The influence of Pleistocene glacial refugia on tawny owl genetic diversity and phylogeography in western Europe

The glacial refugia hypothesis indicates that during the height of the Pleistocene glaciations the temperate species that are today widespread in western Europe must have survived in small and climatically favourable areas located in the southern peninsulas of Iberia, Italy and Balkans. One such species is the tawny owl, a relatively sedentary, nonmigratory bird presently distributed throughout Europe. It is a tree-nesting species closely associated with deciduous and mixed coniferous woodlands. In this study I used control region mtDNA sequences from 187 individuals distributed among 14 populations to determine whether current genetic patterns in tawny owl populations were consistent with postglacial expansion from peninsular refugia. European, North African and Asian tawny owls were found to represent three distinct lineages, where North Africa is the sister clade to all European owls. Within Europe, I found three well-supported clades that correspond to each of the three allopatric refugia. Expansion patterns indicate that owls from the Balkan refugium repopulated most of northern Europe, while expansion out of Iberia and Italy had only regional effects leading to admixture in France. Estimates of population divergence times between refugia populations are roughly similar, but one order of magnitude smaller between Greece and northern Europe. Based on a wide range of mutation rates and generation times, divergence between refugia appears to date to the Pleistocene.     

Signatures of Demography and Recombination at Coding Genes in Naturally-Distributed Populations of Arabidopsis Lyrata Subsp. Petraea

Demography impacts the observed standing level of genetic diversity present in populations. Distinguishing the relative impacts of demography from selection requires a baseline of expressed gene variation in naturally occurring populations. Six nuclear genes were sequenced to estimate the patterns and levels of genetic diversity in natural Arabidopsis lyrata subsp. petraea populations that differ in demographic histories since the Pleistocene. As expected, northern European populations have genetic signatures of a strong population bottleneck likely due to glaciation during the Pleistocene. Levels of diversity in the northern populations are about half of that in central European populations. Bayesian estimates of historical population size changes indicate that central European populations also have signatures of population size change since the last glacial maxima, suggesting that these populations are not as stable as previously thought. Time since divergence amongst northern European populations is higher than amongst central European populations, suggesting that the northern European populations were established before the Pleistocene and survived glaciation in small separated refugia. Estimates of demography based on expressed genes are complementary to estimates based on microsatellites and transposable elements, elucidating temporal shifts in population dynamics and confirming the importance of marker selection for tests of demography.     

Phylogeography and paleodistribution models of a widespread birch (Betula platyphylla Suk.) across East Asia: Multiple refugia,multidirectional expansion,and heterogeneous genetic pattern

Widespread tree species cover large geographical areas and play important roles in various vegetation types. Understanding how these species responded to historical climatic changes is important for understanding community assembly mechanisms with evolutionary and conservation implications. However, the location of refugial areas and postglacial history of widespread trees in East Asia remain poorly known. We combined microsatellite data (63 populations, 1756 individuals) and ecological niche modeling to examine the range‐wide population diversity, genetic structure, and historical demography of a pioneer tree species, Asian white birch (Betula platyphylla Suk.) across East Asia. We found a north‐to‐south trend of declining genetic diversity and five clusters, corresponding to geographical regions. Different clusters were inferred to have diverged through Pleistocene climatic oscillations and have different expansion routes, leading to genetic admixture in some populations. Ecological niche models indicated that the distribution of B. platyphylla during the last glacial maximum still had a large latitude span with slight shifts toward southeast, and northern populations had more variable distribution ranges than those in the south during later climatic oscillations. Our results reflect the relatively stable distribution through the last glacial–interglacial cycles and recent multidirectional expansion of B. platyphylla, providing new hypotheses for the response pattern of widespread tree species to climate change. The gradual genetic pattern from northeast to southwest and alternative distribution dynamics possibly resulted from environmental differences caused by latitude and topographic heterogeneity.     

Complete taxon sampling of the avian genus Pica (magpies) reveals ancient relictual populations and synchronous Late‐Pleistocene demographic expansion across the Northern Hemisphere

Previous studies have suggested that bird populations in east Asia were less affected by Pleistocene climatic fluctuations than those in Europe and North America. However, this is mainly based on comparisons among species. It would be more relevant to analyse geographical populations of widespread species or species complexes. We analyzed two mitochondrial genes and two nuclear introns for all taxa of Pica to investigate 1) which Earth history factors have shaped the lineage divergence, and 2) whether different geographical populations were differently affected by the Pleistocene climatic changes. Our mitochondrial tree recovered three widespread lineages, 1) in east Asia, 2) across north Eurasia, and 3) in North America, respectively, with three isolated lineages in northwest Africa, Arabia and the Qinghai‐Tibet Plateau, respectively. Divergences among lineages took place 1.4–3.1 million yr ago. The northwest African population was sister to the others, which formed two main clades. In one of these, Arabia was sister to Qinghai‐Tibet, and these formed the sister clade to the east Asia clade. The other main clade comprised the North American and north Eurasian clades. There was no or very slight structure within these six geographical clades, including a lack of differentiation between the two North American species black‐billed magpie P. hudsonia and yellow‐billed magpie P. nutalli. Demographic expansion was recorded in the three most widespread lineages after 0.06 Ma. Asymmetric gene flow was recorded in the north Eurasian clade from southwestern Europe eastward, whereas the east Asian clade was rooted in south central China. Our results indicate that the fragmentation of the six clades of Pica was related to climatic cooling and aridification during periods of the Pliocene–Pleistocene. Populations on both sides of the Eurasian continent were similarly influenced by the Pleistocene climate changes and expanded concomitantly with the expansion of steppes. Based on results we also propose a revised taxonomy recognising seven species of Pica.     

Pleistocene climate changes shaped the divergence and demography of Asian populations of the great tit Parus major: evidence from phylogeographic analysis and ecological niche models

Different scales and frequencies of glaciations developed in Europe and Asia during the Pleistocene. Because species’ responses to climate change are influenced by interactive factors including ecology and local topography, the pattern and tempo of species diversification may vary significantly across regions. The great tit Parus major is a widespread Eurasian passerine with a range that encircles the central Asian desert and high‐altitude areas of the Tibetan Plateau. A number of genetic studies have assessed the effect of paleo‐climate changes on the distribution of the European population. However, none have comprehensively addressed how paleo‐climate change affected the distribution of the great tit in China, an apparent hotspot of P. major subspecific diversity. Here, we describe likely paleo‐climatic effects on P. major populations in China based on a combination of phylogeography and ecological niche models (ENMs). We sequenced three mitochondrial DNA markers from 28 populations (213 individuals), and downloaded 112 sequences from outside its Chinese range. As the first step in clarifying the intra‐specific relationships among haplotypes, we attempted to clarify the divergence and demography of populations in China. Phylogeographic analysis revealed that P. major is comprised of five highly divergent clades with geographic breaks corresponding to steep mountains and dry deserts. A previously undescribed monophyletic clade with high genetic diversity, stable niches and a long and independent evolutionary history was detected in the mountainous areas of southwest China. The estimated times at which these clades diverged was traced back to the Early‐Middle Pleistocene (2.19–0.61 mya). Contrary to the post‐LGM (the Last Glacial Maximum) expansion of European populations, demographic history indicates that Asian populations expanded before the LGM after which they remained relatively stable or grew slowly through the LGM. ENMs support this conclusion and predict a similar distribution in the present and the LGM. Our genetic and ecological results demonstrate that Pleistocene climate changes shaped the divergence and demography of P. major in China.     

Demography and the Age of Rare Variants

Large whole-genome sequencing projects have provided access to much rare variation in human populations, which is highly informative about population structure and recent demography. Here, we show how the age of rare variants can be estimated from patterns of haplotype sharing and how these ages can be related to historical relationships between populations. We investigate the distribution of the age of variants occurring exactly twice ( variants) in a worldwide sample sequenced by the 1000 Genomes Project, revealing enormous variation across populations. The median age of haplotypes carrying variants is 50 to 160 generations across populations within Europe or Asia, and 170 to 320 generations within Africa. Haplotypes shared between continents are much older with median ages for haplotypes shared between Europe and Asia ranging from 320 to 670 generations. The distribution of the ages of haplotypes is informative about their demography, revealing recent bottlenecks, ancient splits, and more modern connections between populations. We see the effect of selection in the observation that functional variants are significantly younger than nonfunctional variants of the same frequency. This approach is relatively insensitive to mutation rate and complements other nonparametric methods for demographic inference.     

Distinct invasion sources of common ragweed <Emphasis Type="Italic">(Ambrosia artemisiifolia)</Emphasis> in Eastern and Western Europe

The common ragweed (Ambrosia artemisiifolia L.; Asteraceae) is a North American native that is invading Eurasia. Besides its economic impact on crop yield, it presents a major health problem because of its highly allergenic pollen. The plant was imported inadvertently to Europe in the eighteenth century and has become invasive in several countries. By analyzing French and North American populations, it was previously shown that French populations were best described as a mixture of native sources and that range expansion in France probably involved sequential bottlenecks. Here, our aim was to determine whether Eastern European populations of A. artemisiifolia originated from the previously established French populations or from independent trans-Atlantic colonization events. We used nuclear microsatellite markers to elucidate the relationships among populations from Eastern and Western Europe in relation to populations from a broad survey across the native North American range. We found that A. artemisiifolia from Eastern Europe did not originate from the earlier established French populations but rather represents multiple independent introductions from other sources, or introductions from a not yet identified highly diverse native population. Eastern European populations show comparable amounts of genetic variability as do previously characterized French and North American populations, but analyses of population structure clearly distinguish the two European groups. This suggests separate introductions in Eastern and Western Europe as well as divergent sources for these two invasions, possibly as a result of distinct rules for trade and exchange for Eastern Europe during most of the twentieth century.     

Demographic Inference Reveals African and European Admixture in the North American Drosophila melanogaster Population

Drosophila melanogaster spread from sub-Saharan Africa to the rest of the world colonizing new environments. Here, we modeled the joint demography of African (Zimbabwe), European (The Netherlands), and North American (North Carolina) populations using an approximate Bayesian computation (ABC) approach. By testing different models (including scenarios with continuous migration), we found that admixture between Africa and Europe most likely generated the North American population, with an estimated proportion of African ancestry of 15%. We also revisited the demography of the ancestral population (Africa) and found—in contrast to previous work—that a bottleneck fits the history of the population of Zimbabwe better than expansion. Finally, we compared the site-frequency spectrum of the ancestral population to analytical predictions under the estimated bottleneck model.     

Molecular phylogeny and historical biogeography of the Holarctic wetland leaf beetle of the genus Plateumaris

Leaf beetles of the genus Plateumaris inhabit wetlands across the temperate zone of the Holarctic region. To explore the phylogeographic relationships among North American, East Asian, and European members of this genus and the origin of the species endemic to Japan, we studied the molecular phylogeny of 20 of the 27 species in this genus using partial sequences of mitochondrial cytochrome oxidase subunit I (COI) and the 16S and nuclear 28S rRNA genes. The molecular phylogeny revealed that three species endemic to Europe are monophyletic and sister to the remaining 11 North American and six Asian species. Within the latter clade, North American and Asian species did not show reciprocal monophyly. Dispersal-vicariance analysis and divergence time estimation revealed that the European and North America-Asian lineages diverged during the Eocene. Moreover, subsequent differentiation occurred repeatedly between North American and Asian species, which was facilitated by three dispersal events from North America to Asia and one in the opposite direction during the late Eocene through the late Miocene. Two Japanese endemics originated from different divergence events; one differentiated from the mainland lineage after differentiation from the North American lineage, whereas the other showed a deep coalescence from the North American lineage with no present-day sister species on the East Asian mainland. This study of extant insects provides molecular phylogenetic evidence for ancient vicariance between Europe and East Asia-North America, and for more recent (but pre-Pleistocene) faunal exchanges between East Asia and North America.