Ancestral Range Reconstruction Research Articles

Ancestral range reconstruction of Galliformes: the effects of topology and taxon sampling

AbstractAimWe examined divergence times and biogeography of the avian order Galliformes (which, despite a nearly world‐wide distribution, includes many weak fliers), to test whether current distributions reflect vicariance or long‐distance dispersal. We also tested the impact of taxon sampling and tree topology on our estimates of historical biogeography.LocationWorld‐wide.MethodsWe generated timetrees for all major galliform lineages using several fossil calibrations and a combination of mitochondrial and nuclear data. We compared divergence times and reconstructed ancestral ranges using this timetree and the galliforms from a recent synthetic tree for all birds. Thus, we explored the sensitivity of our conclusions to differences in topology and taxon sampling.ResultsThe results suggest late Cretaceous origins for Megapodiidae and possibly for Cracidae, the earliest diverging families. The other families diversified in the Eocene after the break‐up of Gondwana, contrary to previous suggestions. Both topology and taxon sampling affected the ancestral area estimates, although many nodes were consistent among the approaches.Main conclusionsDivergences of Numididae, Odontophoridae and Phasianidae occurred in Africa, with subsequent dispersal to other continents. Reconstructed ranges for ancestors of the earliest diverging families, Megapodiidae and Cracidae, are less conclusive, but may have involved a South American origin, then dispersal to other continents. Thus, long‐distance dispersal is likely to have been important in galliforms, possibly reflecting more vagile ancestors and repeated range expansions and contractions. There appears to be a trade‐off between the use of trees with rich taxon sampling but limited data, where key taxa can be misplaced, and more robust trees with missing taxa. When biogeographically important taxa are included, complete taxon sampling does not appear necessary for accurate ancestral area reconstruction. Robust trees that include taxa targeted based on their distribution may be the best way to improve our understanding of historical biogeography.

Tales of dracula ants: the evolutionary history of the ant subfamily Amblyoponinae (Hymenoptera: Formicidae)

AbstractThe ants in the subfamily Amblyoponinae are an old, relictual group with an unusual suite of morphological and behavioural features. Adult workers pierce the integument of their larvae to imbibe haemolymph, earning them the vernacular name ‘dracula ants’. We investigate the phylogeny of this group with a data set based on 54 ingroup taxa, 23 outgroups and 11 nuclear gene fragments (7.4 kb). We find that the genus Opamyrma has been misplaced in this subfamily: it is a member of the leptanilline clade and sister to all other extant Leptanillinae. Transfer of Opamyrma to Leptanillinae renders the Amblyoponinae monophyletic. The enigmatic Afrotropical genus Apomyrma is sister to all other amblyoponines, and the latter cleave into two distinct and well‐supported clades, here termed POA and XMMAS. The POA clade, containing Prionopelta, Onychomyrmex and Amblyopone, is well resolved internally, and its structure supports synonymy of the genus Concoctio under Prionopelta (syn.n.). The XMMAS clade comprises two well‐supported groups: (i) a predominantly Neotropical clade, for which we resurrect the genus name Fulakora (stat.r., stat.n.), with junior synonyms Paraprionopelta (syn.n.) and Ericapelta (syn.n.); and (ii) the remaining taxa, or ‘core XMMAS’, which are manifested in our study as a poorly resolved bush of about a dozen lineages, suggesting rapid radiation at the time of their origin. Most of these XMMAS lineages have been assigned to the catch‐all genus Stigmatomma, but the more distinctive elements have been treated as separate genera (Xymmer, Mystrium, Myopopone and Adetomyrma). Resolution of basal relationships in the core XMMAS clade and reconfiguration of ‘Stigmatomma’ to restore monophyly of all named genera will require more extensive genetic data and additional morphological analysis. However, the genus Bannapone can be synonymized under Stigmatomma (syn.n.) because it is embedded within a clade that contains S. denticulatum, the type species of Stigmatomma. Divergence dating analysis indicates that crown Amblyoponinae arose in the mid‐Cretaceous, about 107 Ma (95% highest probability density: 93–121 Ma). The POA and XMMAS clades have estimated crown ages of 47 and 73 Ma, respectively. The initial burst of diversification in the core XMMAS clade occurred in the Late Paleocene/Early Eocene (50–60 Ma). Ancestral range reconstruction suggests that amblyoponines originated in the Afrotropics, and dispersed to the Indo‐Malayan region and to the New World. During none of these dispersal events did the ants break out of their cryptobiotic lifestyle.

Phylogenomics, biogeography and diversification of obligate mealybug-tending ants in the genus Acropyga

Acropyga ants are a widespread clade of small subterranean formicines that live in obligate symbiotic associations with root mealybugs. We generated a data set of 944 loci of ultraconserved elements (UCEs) to reconstruct the phylogeny of 41 representatives of 23 Acropyga species using both concatenation and species-tree approaches. We investigated the biogeographic history of the genus through divergence dating analyses and ancestral range reconstructions. We also explored the evolution of the Acropyga-mealybug mutualism using ancestral state reconstruction methods. We recovered a highly supported species phylogeny for Acropyga with both concatenation and species-tree analyses. The age for crown-group Acropyga is estimated to be around 30Ma. The geographic origin of the genus remains uncertain, although phylogenetic affinities within the subfamily Formicinae point to a Paleotropical ancestor. Two main Acropyga lineages are recovered with mutually exclusive distributions in the Old World and New World. Within the Old World clade, a Palearctic and African lineage is suggested as sister to the remaining species. Ancestral state reconstructions indicate that Old World species have diversified mainly in close association with xenococcines from the genus Eumyrmococcus, although present-day associations also involve other mealybug genera. In contrast, New World Acropyga predominantly evolved with Neochavesia until a recent (10–15Ma) switch to rhizoecid mealybug partners (genus Rhizoecus). The striking mandibular variation in Acropyga evolved most likely from a 5-toothed ancestor. Our results provide an initial evolutionary framework for extended investigations of potential co-evolutionary interactions between these ants and their mealybug partners.

Did a Miocene–Pliocene island isolation sequence structure diversification of funnel web spiders in the Taiwan‐Ryukyu Archipelago?

AbstractAimWe tested the competing hypotheses concerning the relative importance of Pleistocene versus Miocene–Pliocene geological events for the formation of endemism in an Asian archipelago using the Macrothele taiwanensis (Hexathelidae) species group.LocationTaiwan‐Ryukyu Archipelago.MethodsWe estimated phylogenetic trees from cytochrome oxidase I subunit (COI) and 16S rRNA (16S) gene regions and employed Bayesian ancestral range reconstructions to investigate previously debated models of lineage diversification in the Taiwan‐Ryukyu Archipelago. To evaluate alternative geological timeframes for their importance in shaping the genetic structure of funnel web spiders, we used five time calibration schemes to estimate timing of divergence, infer ancestral distributions, and to reconstruct historical demographic changes in each lineage. We tested taxonomic boundaries with two species delimitation procedures.ResultsOur results indicate a north‐to‐south isolation sequence of the M. taiwanensis group: the Amami lineage diverged first, then Yaeyama, and finally the Taiwanese lineages. Divergence time estimation and population demographic change analyses indicate that Pleistocene climate fluctuations minimally impacted the genetic structure of these spiders. Instead, estimated divergence events correspond to Miocene–Pliocene geological events, strongly supporting a much older timeframe for diversification. The results of species delimitation analyses coincide well with morphological differences observed among the island populations, reinforcing inferred species boundaries, and at least three potential cryptic species were statistically detected within Taiwan.Main conclusionsMiocene–Pliocene geological events appear to have contributed disproportionately to diversification in the M. taiwanensis species group. The clear association between geographical area, genetic structure and statistical species delimitation strongly supports an interpretation of allopatric speciation. We advocate comparing our results with those derived from additional study organisms with similar life histories to further explore the Miocene–Pliocene diversification hypothesis.

Phylogeny of Allium L. subgenus Anguinum (G. Don. ex W.D.J. Koch) N. Friesen (Amaryllidaceae)

The disjunct distribution of the subgenus Anguinum of the genus Allium makes it a good candidate to test models of Northern hemisphere biogeography. Here we conduct phylogenetic analysis with the nuclear marker ITS and three different chloroplast markers (rps16 intron, rbcL-atpB spacer, rpl32-trnL spacer). Divergence time estimations (Beast) relying on published ITS substitution rates and ancestral range reconstructions were calculated to elucidate the biogeographical history of the subgenus. Additionally we compiled distribution maps for all species with data taken from the literature, herbariums and data from field observations. The main radiation of the subgenus took place in the last one million years and is still going on. They have their origins in the mid Miocene in East Asia and were highly influenced by the climate fluctuations in the Pliocene/Pleistocene period. Conflicting tree topologies between nuclear and cpDNA markers of Allium tricoccum Solander indicate that the species is of hybridogenous origin. Cloning the ITS sequence revealed the parental copies and confirmed our conclusion. One originated from the Eurasian and the other from the East Asian clade. We were able to show that it reached North America most likely via the Beringia around 2.5mya (95% HPD of 0.35–5.26mya). Our data suggest that Allium victorialis L. is only distributed in mountain pastures in Europe as it forms a well-supported clade in the ITS tree. In the analysis of the molecular markers we found two distinct types of Allium ochotense Prokh. and we suggest splitting the species based on Prokhanov’s (1930) proposal. Taxonomical remarks and an identification key to all species of the subgenus Anguinum is provided.

Land connectivity changes and global cooling shaped the colonization history and diversification of New World quail (Aves: Galliformes: Odontophoridae)

AbstractAimRange disjunctions are frequent in birds, but the relative roles of vicariance and long‐distance dispersal in producing them are debated. Odontophorid quail are widespread in tropical and temperate habitats in the Americas, yet recent phylogenetic studies support the view that they are sister to sub‐Saharan African Ptilopachus rather than the widespread Phasianidae as formerly believed. To understand how this 10,000 km range disjunction arose in relatively non‐vagile birds, we reconstructed colonization history and diversification of odontophorids with respect to hypothesized dry‐land connections between continents (North Atlantic, Beringian, Panamanian) that would have facilitated faunal exchange.LocationAfrica, Nearctic and Neotropics.MethodsWe inferred a fossil‐calibrated odontophorid phylogeny from DNA sequences (three mitochondrial genes and eight nuclear introns) and modelled ancestral ranges with six probabilistic biogeographical models. We used the Akaike information criterion (AIC) to select the best‐fit biogeographical model.ResultsPtilopachus and New World quail shared an Old World ancestor c. 32 Ma. During this period, Beringia connected the Nearctic and Palaearctic, and global temperatures were high, such that presence of temperate organisms at high latitudes and direct dispersal across land connections were feasible. The extant New World quail began diversifying in Central America c. 18 Ma; timing estimates and ancestral range reconstructions support the hypothesis that New World quail colonized and diversified in South America following closure of the Isthmus of Panama.Main conclusionsThe Africa/New World range disjunction between New World quail and Ptilopachus is the result of changes in Earth and climate history, combined with range expansion and diversification in the New World, and range contraction in the Old World. We find no evidence for overwater dispersal in New World quail.

Within-island speciation with an exceptional case of distinct separation between two sibling lizard species divided by a narrow stream

Delimitation of genetic and geographic boundaries between species is a focus of evolutionary biology. In this study, we demonstrated fine-scale differentiation of Takydromus formosanus species complex comprising four insular endemics on Taiwan Island. Phylogeny and ancestral range reconstruction based on mitochondrial DNA sequences of 430 Takydromus lizards (405 lizards of this complex throughout their distribution range, and 25 lizards from 11 other species) indicated that the major branching process occurred within Taiwan, which represented a solid evidence of within-island speciation on this small island. We further demonstrated an exceptional case of a pair of sister species, T. viridipunctatus and T. luyeanus, that were separated by a narrow stream with a width of only 15m. This pattern might be one of the narrowest contact zones ever documented in terrestrial vertebrates. To evaluate the level of genetic introgression between these sister species, a fine-scale collection of another 382 lizards was conducted along a transect line across the stream. A total of 13 microsatellite markers and mtDNA genotyping was used to detect a low proportion of hybrids (5.7–9.9% from STRUCTURE, and 2.3% from DAPC). Our results indicated that the two clades are highly differentiated across this extremely short distance.

A multi-gene dataset reveals a tropical New World origin and Early Miocene diversification of croakers (Perciformes: Sciaenidae)

Widely distributed groups of living animals, such as the predominantly marine fish family Sciaenidae, have always attracted the attention of biogeographers to document the origins and patterns of diversification in time and space. In this study, the historical biogeography of the global Sciaenidae is reconstructed within a molecular phylogenetic framework to investigate their origin and to test the hypotheses explaining the present-day biogeographic patterns. Our data matrix comprises six mitochondrial and nuclear genes in 93 globally sampled sciaenid species from 52 genera. Within the inferred phylogenetic tree of the Sciaenidae, we identify 15 main and well-supported lineages; some of which have not been recognized previously. Reconstruction of habitat preferences shows repeated habitat transitions between marine and euryhaline environments. This implies that sciaenids can easily adapt to some variations in salinity, possibly as the consequence of their nearshore habitats and migratory life history. Conversely, complete marine/euryhaline to freshwater transitions occurred only three times, in South America, North America and South Asia. Ancestral range reconstruction analysis concomitant with fossil evidence indicates that sciaenids first originated and diversified in the tropical America during the Oligocene to Early Miocene before undergoing two range expansions, to Eastern Atlantic and to the Indo-West Pacific where a maximum species richness is observed. The uncommon biogeographic pattern identified is discussed in relation to current knowledge on origin of gradients of marine biodiversity toward the center of origin hypothesis in the Indo-West Pacific.

Recurrent camouflaged invasions and dispersal of an Asian freshwater gastropod in tropical Africa.

BackgroundNon-indigenous taxa currently represent a large fraction of the species and biomass of freshwater ecosystems. The accumulation of invasive taxa in combination with other stressors in these ecosystems may alter the habitats to which native taxa are adapted, which could elicit evolutionary changes in native populations and their ecological interactions. Assessing ecological and evolutionary consequences of invasions simultaneously may therefore be the most effective approach to study taxa with complex invasion histories. Here we apply such an integrated approach to the cerithioid gastropod Melanoides tuberculata, a model system in invasion biology.ResultsMolecular phylogenetics and ancestral range reconstructions allowed us to identify several independent Asian invasions in Lakes Malawi and Tanganyika, the Congo River, Nigeria and Cameroon. Some invasive M. tuberculata populations display much variation in shell morphology, and overlap in morphospace with M. tuberculata populations native to Africa. Experiments confirmed great ecophenotyic plasticity in some invasive populations, which, in combination with the overlap in disparity with native populations, masks invaders and their dispersal through Africa. Finally, the results of geographic modeling indicate that cryptic M. tuberculata invasions occurred primarily in densely populated areas.ConclusionsWe reveal the continental nature of invasions of Asian M. tuberculata to Africa. Several of the affected ecosystems have high endemicity in Cerithioidea: Lake Tanganyika has an unparalleled diversity in freshwater cerithioids (>10 endemic genera) and the Congo Basin and Lake Malawi are home to the two largest endemic species clusters of Melanoides in Africa (~12 and ~8 species, respectively). Cerithioids perform ecologically important functions in the benthic ecosystems of African freshwaters, but invaders and ecosystem change pose risks to their native diversity. We draw suggestions for more effective conservation strategies from our integrated approach.Electronic supplementary materialThe online version of this article (doi:10.1186/s12862-015-0296-2) contains supplementary material, which is available to authorized users.

A likelihood inference of historical biogeography in the world’s most diverse terrestrial vertebrate genus: Diversification of direct-developing frogs (Craugastoridae: Pristimantis) across the Neotropics

The geology of the northern Andean region has driven the evolutionary history of Neotropical fauna through the creation of barriers and connections that have resulted in speciation and dispersal events, respectively. One of the most conspicuous groups of anuran fauna in the Andes and surrounding areas is the direct-developing species of the genus Pristimantis. We investigated the molecular phylogenetic placement of 12 species from the montane Andes of Colombia in a broader geographical context with a new genus-level phylogeny in order to identify the role of Andean orogeny over the last 40million years and the effect of elevational differences in diversification of Pristimantis. We examined the biogeographic history of the genus using ancestral range reconstruction by biogeographic regions and elevational ranges. We recognized the middle elevational band (between 1000 and 3000m) in the Northwestern Andes region of Colombia and Ecuador as a focal point for the origin and radiation of Pristimantis species. Additionally, we found several Andean migrations toward new habitats in Central Andes and Merida Andes for some species groups. We suggest that the paleogeological changes in the Northwestern Andes were the main promoter of speciation in Pristimantis, and may have served as a corridor for the dispersion of lowland species.

On the historical biogeography of global Galliformes: ancestral range and diversification patterns

In this study, the ancestral distributional ranges and the tempo of diversification patterns of global Galliformes were investigated. Different diversification models characterizing possible tempo patterns were fitted and compared onto the phylogenetic tree for the 197 Galliforme species, consisting of a constant-speciation and constant-extinction model (CONSTANT), a decreasing-speciation and constant-extinction model (SPVAR), a constant-speciation and increasing-extinction model (EXVAR) and a decreasing-speciation and increasing-extinction model (BOTHVAR). Ancestral range reconstruction was conducted using the dispersal-extinction-cladogenesis model. A constant-diversification-rate (CONSTANT) model best quantified the historical speciation patterns of this avian assemblage through model selection. Clade age and species richness are significantly and positively correlated. The most recent common ancestor for Galliformes species was originally found in the disjunctive regions between Southeast Asia and North America. High-frequency dispersal events were identified across the whole evolutionary time. The constant diversification rate for global Galliforme species implied that there were no diversification rate-shifting trends for Galliformes species. The present study may contribute to the understanding of the ecology and diversity patterns of Galliformes from the perspective of historical biogeography, although some limitations existed.

Phylogenetic position of the bee genera Ancyla and Tarsalia (Hymenoptera: Apidae): A remarkable base compositional bias and an early Paleogene geodispersal from North America to the Old World

We address the phylogenetic position of the bee genera Tarsalia and Ancyla (currently forming the tribe Ancylaini) on the basis of morphological, molecular and combined data. We assembled a matrix of 309 morphological characters and 5246 aligned nucleotide positions from six nuclear genes (28S, EF-1a, wingless, POL2, LW-Rhodopsin, NAK). In addition to both constituent genera of Ancylaini, we include all three subtribes of the Eucerini as well as a large number of other tribes from the “eucerine line”. The morphological data suggest Ancyla to be sister to Tarsalia+Eucerini and analyses of the entire molecular dataset suggest Tarsalia to be sister to Ancyla+Eucerini. However, analyses of the combined dataset suggests the Ancylaini to be monophyletic. We address possible bias within the molecular data and show that the base composition of two markers (EF-1a and NAK) is significantly heterogeneous among taxa and that this heterogeneity is strong enough to overcome the phylogenetic signal from the other markers. Analyses of a molecular matrix where the heterogeneous partitions have been RY-recoded yield trees that are better resolved and have higher nodal support values than those recovered in analyses of the non-recoded matrix, and strongly suggest the Ancylaini to be a monophyletic sister group to the Eucerini. A dated phylogeny and ancestral range reconstructions suggest that the common ancestor of the Ancylaini reached the Old World from the New World most probably via the Thulean Land Bridge in a time window between 69 and 47mya, a period that includes the Early Eocene Climatic Optimum. No further exchanges between the New World and the Old World are implied by our data until the period between 22mya and 13.9mya. These more recent faunal exchanges probably involved geodispersal over the Bering Land Bridge by less thermophilic lineages.

New insights into tateid gastropods and their radiation on Fiji based on anatomical and molecular methods (Caenogastropoda: Truncatelloidea)

The South Pacific archipelago of Fiji is characterized by a predominantly Indo-Malesian flora and fauna. We provide a first systematic study on Fiji's tateid gastropods – previously classified as Hydrobiidae – describing 18 new species, combining morphological, anatomical, and molecular data. The molecular phylogeny of tateid gastropods based on 16S rRNA and cytochrome c oxidase subunit I (COI) showed that the species from Fiji were closer related to New Zealand than to Australian or New Caledonian taxa, which is rather exceptional. Performing an ancestral range reconstruction we inferred the colonization history across the two main islands. The radiation had its origin in southern Viti Levu, with a subsequent dispersal over the western and central parts of the island. The chronology of the radiation over eastern Viti Levu and Vanua Levu remained unresolved because of incomplete lineage sorting, a phenomenon typical for young radiations. © 2014 The Linnean Society of London

Pleistocene diversification of the Pomacentrus coelestis species complex (Pisces: Pomacentridae): historical biogeography and species boundaries

Pleistocene eustatic changes in sea level are often invoked to explain genetic divergence among marine organisms. However, molecular phylogenies have revealed relatively few examples of speciation events dating to the Pleistocene. We present a species-level hypothesis of the timing of evolution for the Pomacentrus coelestis species complex (Pomacentridae), based on the nuclear S7 intron and the mitochondrial Cytb gene, and reconstruct ancestral range distributions across the timetree. Ancestral range reconstruction suggests the complex originated in the Coral Triangle and East Indian Ocean, with subsequent range expansion outward from this region. We suggest that land barriers to dispersal (e.g., Indo-Pacific barrier) may be responsible for the divergence between Indian (P. alleni, P. similis, P. caeruleopunctatus, and P. caeruleus) and Pacific (P. micronesicus, P. auriventris, and P. coelestis) species groups, and subsequent isolation by Pleistocene sea-level fluctuations in certain areas of the Coral Triangle (glacial refugia) may play an important role in the diversification of this species complex. Additionally, our analyses show cryptic lineages within P. micronesicus and highlight the need for comprehensive sampling within and among species to reveal recent speciation events.

Explicit tests of palaeodrainage connections of southeastern North America and the historical biogeography of Orangethroat Darters (Percidae: Etheostoma:Ceasia)

The alteration in palaeodrainage river connections has shaped patterns of speciation, genetic diversity and the geographical distribution of the species-rich freshwater fauna of North America. The integration of ancestral range reconstruction methods and divergence time estimates provides an opportunity to infer palaeodrainage connectivity and test alternative palaeodrainage hypotheses. Members of the Orangethroat Darter clade, Ceasia, are endemic to southeastern North America and occur north and south of the Pleistocene glacial front, a distributional pattern that makes this clade of closely related species an ideal system to investigate the number and location of glacial refugia and compare alternative hypotheses regarding the proposed evolution of the Teays-Mahomet palaeodrainage. This study utilized time-calibrated mitochondrial and nuclear gene phylogenies and present-day geographical distributions to investigate hypothesized Teays-Mahomet River connections through time using a dispersal-extinction-cladogenesis (DEC) framework. Results of DEC ancestral area reconstructions indicate that the Teays-Mahomet River was a key dispersal route between disjunct highland regions connecting the Mississippi River tributaries to the Old-Ohio Drainage minimally at two separate occasions during the Pleistocene. There was a dynamic interplay between palaeodrainage connections through time and postglacial range expansion from three glacial refugia that shaped the current genetic structure and geographical distributions of the species that comprise Ceasia.

Molecular phylogeny and biogeography of the Hawaiian craneflies Dicranomyia (Diptera: Limoniidae).

The Hawaiian Diptera offer an opportunity to compare patterns of diversification across large and small endemic radiations with varying species richness and levels of single island endemism. The craneflies (Limoniidae: Dicranomyia) represent a small radiation of 13 described species that have diversified within the Hawaiian Islands. We used Bayesian and maximum likelihood approaches to generate a molecular phylogeny of the Hawaiian Dicranomyia using a combination of nuclear and mitochondrial loci, estimated divergence times and reconstructed ancestral ranges. Divergence time estimation and ancestral range reconstruction suggest that the colonization that led to most of the diversity within the craneflies arrived prior to the formation of Kauai and demonstrates that the two major clades within that radiation contrast sharply in their patterns of diversification.

A tale of migrations from east to west: the Irano‐Turanian floristic region as a source of Mediterranean xerophytes

AbstractAimThe Irano‐Turanian (IT) floristic region is characterized by high levels of endemicity. Despite its potential role as a cradle of xerophytic taxa for neighbouring areas, its biogeographical history remains poorly studied. Haplophyllum, a diagnostic element of the IT region, was used as a model to discriminate between alternative biogeographical scenarios for the evolution of the region and, more specifically, to investigate whether it served as a source of xerophytes for the colonization of the Mediterranean Basin.LocationIrano‐Turanian floristic region (Central Asia and West Asiatic areas) and Mediterranean floristic region (western and eastern parts of the Mediterranean Basin).MethodsThree chloroplast DNA regions were sequenced in 77 accessions of Haplophyllum and 37 accessions from other subfamilies of Rutaceae. To elucidate the temporal and spatial evolution of Haplophyllum in the IT and Mediterranean regions, we performed Bayesian molecular dating analyses with four fossil constraints and ancestral range reconstructions, respectively.ResultsOur molecular dating and ancestral area reconstruction analyses suggest that Haplophyllum originated in the Central Asian part of the IT region during the early Eocene and started to diversify in situ during the early Oligocene, soon after the vanishing of the Tethys Ocean. Our results further imply that Haplophyllum later invaded the eastern Mediterranean Basin in the middle‐to‐late Miocene, concomitantly with the Paratethys Salinity Crisis and rapid palaeobiogeographical changes in the proto‐Mediterranean. Finally, Haplophyllum diversified in the western Mediterranean in the early Pliocene at the end of the Messinian Salinity Crisis.Main conclusionsThe IT floristic region can serve as a ‘donor’ of xerophytic taxa to ‘recipient’ neighbouring regions, including the Mediterranean floristic region. The climatic/geological processes during the Miocene–Pliocene, by increasing aridity and topographic heterogeneity, facilitated range shifts and allopatric speciation in the region.

Diversity, relationships, and biogeography of the lambeosaurine dinosaurs from the European Archipelago, with description of the New Aralosaurin Canardia garonnensis.

We provide a thorough re-evaluation of the taxonomic diversity, phylogenetic relationships, and historical biogeography of the lambeosaurine hadrosaurids from the European Archipelago. Previously published occurrences of European Lambeosaurinae are reviewed and new specimens collected from upper Maastrichtian strata of the south-central Pyrenees are described. No support is found for the recognition of European saurolophines in the available hadrosaurid materials recovered so far from this area. A new genus and species of basal lambeosaurine, Canardia garonnensis, is described on the basis of cranial and appendicular elements collected from upper Maastrichtian strata of southern France. C. garonnensis differs from all other hadrosaurids, except Aralosaurus tuberiferus, in having maxilla with prominent subrectangular rostrodorsal flange; it differs from A. tuberiferus in a few maxillary and prefrontal characters. Together with A. tuberiferus, C. garonnensis integrates the newly recognized tribe Aralosaurini. Inference of lambeosaurine interrelationships via maximum parsimony analysis indicates that the other three known European lambeosaurines are representatives of two additional subclades (tribes) of these hadrosaurids: Tsintaosaurini (Pararhabdodon isonensis) and Lambeosaurini (the Arenysaurus ardevoli-Blasisaurus canudoi clade). The tribes Aralosaurini, Tsintaosaurini, Lambeosaurini, and Parasaurolophini are formally defined and diagnosed for the first time. Three event-based quantitative methods of ancestral range reconstruction were implemented to infer the historical biogeography of European lambeosaurines: Dispersal-Vicariance Analysis, Bayesian Binary MCMC, and Dispersal-Extinction-Cladogenesis. The results of these analyses, coupled with the absence of pre-Maastrichtian lambeosaurines in the Mesozoic vertebrate fossil record of Europe, favor the hypothesis that aralosaurins and tsintaosaurins were Asian immigrants that reached the Ibero-Armorican island via dispersal events sometime during the Maastrichtian. Less conclusive is the biogeographical history of European lambeosaurins; several scenarios, occurring sometime during the Maastrichtian, are possible, from vicariance leading to the splitting of Asian or North American from European ranges to a dispersal event from North America to the European Archipelago.

Mitogenomic Evidence for an Indo-West Pacific Origin of the Clupeoidei (Teleostei: Clupeiformes)

The clupeoid fishes are distributed worldwide, with marine, freshwater and euryhaline species living in either tropical or temperate environments. Regional endemism is important at the species and genus levels, and the highest species diversity is found in the tropical marine Indo-West Pacific region. The clupeoid distribution follows two general pattern of species richness, the longitudinal and latitudinal gradients. To test historical hypotheses explaining the formation of these two gradients, we have examined the early biogeography of the Clupeoidei in reconstructing the evolution of their habitat preferences along with their ancestral range distributions on a time-calibrated mitogenomic phylogeny. The phylogenetic results support the distinction of nine main lineages within the Clupeoidei, five of them new. We infer several independent transitions from a marine to freshwater environment and from a tropical to temperate environment that occurred after the initial diversification period of the Clupeoidei. These results combined with our ancestral range reconstruction hypothesis suggest that the probable region of origin and diversification of the Clupeoidei during the Cretaceous period was the tropical marine precursor to the present Indo-West Pacific region. Thus, our study favors the hypotheses of “Region of origin” and “Tropical conservatism” to explain the origins of the longitudinal and latitudinal gradients of clupeoid species richness, respectively. Additional geological and paleontological evidence further define the tropical marine paleo-region of origin as the eastern Tethys Sea region. The Cretaceous fossil record of the Clupeoidei is partially incongruent with the results here as it contains taxa found outside this region. We discuss three possible causes of conflict between our biogeographical hypothesis and the distributions of the Cretaceous clupeoid fossils: regional extinction, incomplete taxonomic sampling and incorrect timescale estimation.

Inferring the biogeographic origins of inter‐continental disjunct endemics using a Bayes‐DIVA approach

AbstractThe arcto‐Tertiary relictual flora is comprised of many genera that occur non‐contiguously in the temperate zones of eastern Asia, Europe, eastern North America, and western North America. Within each distributional area, species are typically endemic and may thus be widely separated from closely related species within the other areas. It is widely accepted that this common pattern of distribution resulted from of the fragmentation of a once more‐continuous arcto‐Tertiary forest. The historical biogeographic events leading to the present‐day disjunction have often been investigated using a phylogenetic approach. Limitations to these previous studies have included phylogenetic uncertainty and uncertainty in ancestral range reconstructions. However, the recently described Bayes‐DIVA method handles both types of uncertainty. Thus, we used Bayes‐DIVA analysis to reconstruct the stem lineage distributions for 185 endemic lineages from 23 disjunct genera representing 17 vascular plant families. In particular, we asked whether endemic lineages within each of the four distributional areas more often evolved from (1) widespread ancestors, (2) ancestors dispersed from other areas, or (3) endemic ancestors. We also considered which of these three biogeographic mechanisms may best explain the origins of arcto‐Tertiary disjunct endemics in the neotropics. Our results show that eastern Asian endemics more often evolved from endemic ancestors compared to endemics in Europe and eastern and western North America. Present‐day endemic lineages in the latter areas more often arose from widespread ancestors. Our results also provide anecdotal evidence for the importance of dispersal in the biogeographic origins of arcto‐Tertiary species endemic in the neotropics.