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At least 37 records · Page 2Linked to original sources
PubMed2001

Phylogeny and biogeography of the flowering plant genus Styrax (Styracaceae) based on chloroplast DNA restriction sites and DNA sequences of the internal transcribed spacer region.

Phylogenetic relationships within the flowering plant genus Styrax were investigated with DNA sequence data from the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (nrDNA) and with chloroplast DNA restriction site data from the genes trnK, rpoC1, and rpoC2. The data sets from each genome were analyzed separately and in combination with parsimony methods. The results strongly support the monophyly of each of the four series of the genus but provide little phylogenetic resolution among them. Reticulate evolution may at least partly explain discordance between the molecular phylogenetic estimates and a prior morphological estimate within series Cyrta. The historical biogeography of the genus was inferred with unweighted parsimony character optimization of trees recovered from a combined ITS and morphological data set, after a series of combinability tests for data set congruence was conducted. The results are consistent with the fossil record in supporting a Eurasian origin of Styrax. The nested phylogenetic position of the South American members of the genus within those from southern North America and Eurasia suggests that the boreotropics hypothesis best explains the amphi-Pacific tropical disjunct distribution occurring within section Valvatae. The pattern of relationship recovered among the species of section Styrax ((western North America + western Eurasia) (eastern North America + eastern Eurasia)) is rare among north-temperate Tertiary forest relicts. The monophyly of the group of species from western North America and western Eurasia provides qualified support for the Madrean-Tethyan hypothesis, which posits a Tertiary floristic connection among the semiarid regions in which these taxa occur. A single vicariance event between eastern Asia and eastern North America accounts for the pattern of relationship among intercontinental disjuncts in series Cyrta.

Binding Sites↗
PubMed2001

Molecular phylogeny and biogeography of West Indian toads (Anura: Bufonidae).

Toads of the Bufo peltocephalus Group (Anura: Bufonidae) occur throughout the Greater Antilles (Cuba to the Virgin Islands), a geographic region of relatively high endemicity. Previous morphological and immunological studies suggested that the West Indian toads are a monophyletic lineage derived from Neotropical Bufo but were unable to clarify relationships within the group. We examined the evolutionary relationships and biogeography of this group of frogs by collecting approximately 2 kb of mitochondrial DNA sequence data from eight West Indian species and selected non-West Indian species from the New World and the Old World. Our analyses support the monophyly of native West Indian toads and a New World origin for the group. Relationships among the West Indian species are less certain, but a Cuban lineage is defined in most analyses.

Animals↗
PubMed2006

Where did the chili get its spice? Biogeography of capsaicinoid production in ancestral wild chili species.

The biogeography of pungency in three species of wild chili in the chaco and surrounding highland habitats of southeastern Bolivia is described. We report that Capsicum chacoense, C. baccatum, and C. eximium are polymorphic for production of capsaicin and its analogs, such that completely pungent and completely nonpungent individuals co-occur in some populations. In C. chacoense, the density of plants and the proportion of pungent plants increased with elevation. Above 900 m, all individuals in all populations except two were pungent; nonpungent individuals in at least one of the two polymorphic populations were likely a result of spreading by humans. The occurrence of pungent and nonpungent individuals in three species of ancestral Capsicum and the geographic variation of pungency within species suggest that production of capsaicin and its analogs entails both costs and benefits, which shift from one locality to another. Determining the selection pressures behind such shifts is necessary to understand the evolution of pungency in chilies.

Capsaicin↗
PubMed2005

Island biogeography and landscape structure: integrating ecological concepts in a landscape perspective of anthropogenic impacts in temporary wetlands.

Although our understanding of environmental risk assessment in temporary wetlands has been improved by the use of multi-species toxicity testing, we still know little of how landscape variables mediate the strength of, and recovery from, anthropogenic stress in such ecosystems. To bridge this research gap, we provide a theoretical framework of the response of temporary wetlands to anthropogenic disturbance along a habitat-isolation continuum based on island biogeography theory, landscape ecology and dispersal and colonization strategies of temporary wetland organisms.

Animals↗
PubMed2004

The resurrection of oceanic dispersal in historical biogeography.

Geographical distributions of terrestrial or freshwater taxa that are broken up by oceans can be explained by either oceanic dispersal or vicariance in the form of fragmentation of a previously contiguous landmass. The validation of plate-tectonics theory provided a global vicariance mechanism and, along with cladistic arguments for the primacy of vicariance, helped create a view of oceanic dispersal as a rare phenomenon and an explanation of last resort. Here, I describe recent work that suggests that the importance of oceanic dispersal has been strongly underestimated. In particular, molecular dating of lineage divergences favors oceanic dispersal over tectonic vicariance as an explanation for disjunct distributions in a wide variety of taxa, from frogs to beetles to baobab trees. Other evidence, such as substantial gene flow among island populations of Anolis lizards, also indicates unexpectedly high frequencies of oceanic dispersal. The resurrection of oceanic dispersal is the most striking aspect of a major shift in historical biogeography toward a more even balance between vicariance and dispersal explanations. This new view implies that biotas are more dynamic and have more recent origins than had been thought previously. A high frequency of dispersal also suggests that a fundamental methodological assumption of many biogeographical studies--that vicariance is a priori a more probable explanation than dispersal--needs to be re-evaluated and perhaps discarded.

Journal Article↗
PubMed2004

Molecular phylogeny and biogeography of the endemic Hawaiian Succineidae (Gastropoda: Pulmonata).

The endemic Hawaiian Succineidae represent an important component of the exceptionally diverse land snail fauna of the Hawaiian Islands, yet they remain largely unstudied. We employed 663-bp fragments of the cytochrome oxidase I (COI) mitochondrial gene to investigate the evolution and biogeography of 13 Hawaiian succineid land snail species, six succineid species from other Pacific islands and Japan, and various outgroup taxa. Results suggest that: (1) species from the island of Hawaii are paraphyletic with species from Tahiti, and this clade may have had a Japanese (or eastern Asian) origin; (2) species from five of the remaining main Hawaiian islands form a monophyletic group, and the progression rule, which states that species from older islands are basal to those from younger islands, is partially supported; no geographic origin could be inferred for this clade; (3) succineids from Samoa are basal to all other succineids sampled (maximum likelihood) or unresolved with respect to the other succineid clades (maximum parsimony); (4) the genera Succinea and Catinella are polyphyletic. These results, while preliminary, represent the first attempt to reconstruct the phylogenetic pattern for this important component of the endemic Hawaiian fauna.

Animals↗
PubMed2004

Widespread polyphyly among Alopiinae snail genera: when phylogeny mirrors biogeography more closely than morphology.

Consider a group of species that is evenly divided by an easily identifiable complex morphological character. Most biologists would assume that this character should provide better phylogenetic information than, say, the spatial distribution of these species over a fairly continuous 500-km radius area. Paradoxically, this is not the case among terrestrial snail genera in the clausiliid subfamily Alopiinae. Phylogenetic analysis using the nuclear markers ITS1/ITS2 and mitochondrial markers COI/12S reveals widespread homoplasy in the clausilial apparatus (a complex aperture-closing mechanism), and concomitant extensive polyphyly among Carinigera, Isabellaria, and Sericata. In contrast, phylogenetic relationships as revealed by molecular data are closely congruent with biogeography at a relatively small scale. A combination of extremely low vagility and extremely high morphological convergence has conspired to produce this unexpected result. Implications as to the function of the clausilial apparatus are discussed.

Animals↗
PubMed2004

Historical biogeography of Mediterranean trout.

Complete sequencing of the mitochondrial control region was used to describe phylogenetic relationships of brown trout populations (Salmo trutta) in the Mediterranean river basins of Iberia and to review the historical biogeography of trout from the Mediterranean regions. Phylogenetic relationships among trout lineages suggested that the Danubian one is the most ancestral, in accordance with the eastern origin of most of the European freshwater fish species. Nested-clade and mismatch analyses suggested that the present distribution of haplotypes of the Adriatic and Mediterranean lineages resulted from population expansions originated, respectively, from central and western Europe, which favoured extensive secondary contacts between lineages. Reduced diversity detected within 50% of the analysed populations and large intrabasin differentiation indicated restricted gene flow in post-glacial periods.

Animals↗
PubMed2005

Biogeography and divergence times in the mulberry family (Moraceae).

The biogeographical history of the mulberry family (Moraceae) was investigated using phylogenetic inferences from nuclear and chloroplast DNA, molecular dating with multiple fossil calibrations, and independent geological evidence. The Moraceae are centered in the tropics which has invited the hypothesis that the family has Gondwanan origins and extant distribution is the result of vicariance due to the break-up of Gondwana. However, the cosmopolitan distribution of Moraceae suggests a more complicated biogeographical history. The timing and location of Moraceae diversification also bears on the origin of the fig pollination mutualism, a model for the study of coevolution and specialization. Recent molecular dating of pollinating fig wasps suggested that an ancient Gondwanan origin coupled with vicariance and dispersal could account for the present day distribution of the mutualism. Here, we provide the first assessment of this hypothesis based on dating of figs and their relatives. Minimum age estimates suggest that the Moraceae had diversified by at least the mid-Cretaceous and major clades including the figs may have radiated during the Tertiary after the break-up of Gondwanaland. Molecular evidence together with Eurasian fossils suggest that the early diversification of Moraceae in Eurasia and subsequent migration into the southern hemisphere is at least as plausible as the Gondwanan hypothesis. These findings invite a reevaluation of the biogeography of fig pollination and highlight the need for incorporating multiple sources of evidence in biogeographical reconstructions.

Cell Nucleus↗
PubMed2006

Molecular systematics of Hispaniolan pupfishes (Cyprinodontidae: Cyprinodon): implications for the biogeography of insular Caribbean fishes.

We used sequence variation in the mtDNA control-region and ND2 and cyt b genes to assess the systematics and biogeography of the five species of pupfish (Cyprinodon) on Hispaniola. These include four endemics, the relatively large-bodied Cyprinodon bondi, Cyprinodon nichollsi, and Cyprinodon sp., each from a separate lake in southwestern Hispaniola, and Cyprinodon higuey from a coastal lake in eastern Hispaniola. The fifth species consists of coastal populations referable to Cyprinodon variegatus riverendi. The results indicate that Hispaniola has been invaded by at least two forms, first by a late Pliocene progenitor of Cyprinodon variegatus ovinus and the large-bodied Hispaniolan species, and, more recently, by one or more ancestral forms allied with Cyprinodon variegatus variegatus and C. v. riverendi. Levels of divergence indicate that large expanses of open sea have not acted as long-term barriers to inter-island dispersal of cyprinodontiform fishes. This study, together with the molecular systematics of other insular Caribbean fishes, indicates that most insular groups originated from late Neogene dispersal from the mainland. The patterns of mtDNA variation in Cyprinodon showed little congruence with the species/subspecies taxonomy.

Animals↗
PubMed2006

Molecular phylogeny and biogeography of Picea (Pinaceae): implications for phylogeographical studies using cytoplasmic haplotypes.

The center of diversity is not necessarily the place of origin, as has been established by many plant molecular phylogenies. Picea is a complicated but very important genus in coniferous forests of the Northern Hemisphere, with a high species diversity in Asia. Its phylogeny and biogeography were investigated here using sequence analysis of the paternally inherited chloroplast trnC-trnD and trnT-trnF regions and the maternally inherited mitochondrial nad5 intron 1. We found that the North American P. breweriana and P. sitchensis were basal to the other spruces that were further divided into three clades in the cpDNA phylogeny, and that the New World species harbored four of five mitotypes detected, including two ancestral ones and three endemics. These results, combined with biogeographic analyses using DIVA and MacClade and fossil evidence, suggest that Picea originated in North America, and that its present distribution could stem from two times of dispersal from North America to Asia by the Beringian land bridge, and then from Asia to Europe. Most of the northeastern Asian species and the European P. abies could arise from a recent radiation given the very low interspecific genetic differentiation and pure mitotype of them. Considering that the ancestral mtDNA polymorphism can be preserved in many descendant species, even distantly related ones, we suggest that more species, at least the closely related ones, should be sampled in the phylogeographical study using cytoplasmic haplotypes if possible. In addition, we also discussed the evolution and phylogenetic utility of morphological characters in Picea.

Base Sequence↗
PubMed2006

Molecular phylogenetic analysis of Commiphora (Burseraceae) yields insight on the evolution and historical biogeography of an "impossible" genus.

Expansion of the arid zone of sub-Saharan tropical Africa during the Miocene is posited as a significant contributing factor in the evolution of contemporary African flora. Nevertheless, few molecular phylogenetic studies have tested this hypothesis using reconstructed historical biogeographies of plants within this zone. Here, we present a molecular phylogeny of Commiphora, a predominantly tropical African, arid-adapted tree genus, in order to test the monophyly of its taxonomic sections and identify clades that will help direct future study of this species-rich and geographically widespread taxon. We then use multiple fossil calibrations of Commiphora phylogeny to determine the timing of well-supported diversification events within the genus and interpret these age estimates to determine the relative contribution of vicariance and dispersal in the expansion of Commiphora's geographic range. We find that Commiphora is sister to Vietnamese Bursera tonkinensis and that its crown group radiation corresponds with the onset of the Miocene.

Africa↗
PubMed2006

Phylogeographic structure and historical demography of the western diamondback rattlesnake (Crotalus atrox): A perspective on North American desert biogeography.

The western diamondback rattlesnake (Crotalus atrox) is a prominent member of North American desert and semi-arid ecosystems, and its importance extends from its impact on the region's ecology and imagery, to its medical relevance as a large deadly venomous snake. We used mtDNA sequences to identify population genetic structure and historical demographic patterns across the range of this species, and relate these to broader patterns of historical biogeography of desert and semi-arid regions of the southwestern USA and adjacent Mexico. We inferred a Late Pliocene divergence between peninsular and continental lineages of Crotalus, followed by an Early Mid Pleistocene divergence across the continental divide within C. atrox. Within desert regions (Sonoran and Chihuahuan Deserts, Southern Plains, and Tamaulipan Plain) we observed population structure indicating isolation of populations in multiple Pleistocene refugia on either side of the continental divide, which we attempt to identify. Evidence of post-glacial population growth and range expansion was inferred, particularly in populations east of the continental divide. We observed clear evidence of (probably recent) gene flow across the continental divide and secondary contact of haplotype lineages. This recent gene flow appears to be particularly strong in the West-to-East direction. Our results also suggest that Crotalus tortugensis (Tortuga Island rattlesnake) and a population of 'C. atrox' inhabiting Santa Cruz Island (in the Gulf of California) previously suggested to be an unnamed species, are in fact deeply phylogenetically nested within continental lineages of C. atrox. Accordingly, we suggest C. tortugensis and 'C. atrox' from Santa Cruz Island be placed in the synonymy of C. atrox.

Animals↗
PubMed2006

Molecular phylogeny and biogeography of an ancient Holarctic lineage of mygalomorph spiders (Araneae: Antrodiaetidae: Antrodiaetus).

The mygalomorph spider genera Antrodiaetus and Atypoides (Antrodiaetidae) belong to an ancient lineage that has persisted since at least the Cretaceous. These spiders display a classic disjunct Holarctic distribution with species in the eastern Palaearctic plus the western and eastern Nearctic. Prior phylogenetic analyses of this group have been proposed on the basis of morphology, but lack strong support and independent corroboration. Here we present the first phylogenetic analysis of species-level relationships based on molecular data obtained from the mitochondrial (cytochrome c oxidase subunit I) and nuclear (18S and 28S rRNA) genomes. Analyses corroborate earlier findings that Atypoides forms a paraphyletic grade with respect to Antrodiaetus, and consequently, that genus is formally synonymized under Antrodiaetus. In addition, our results support the relatively early divergence of Antrodiaetus roretzi. Antrodiaetus pacificus is "paraphyletic" with respect to the A. lincolnianus group and is likely an assemblage of numerous species. The final topology based on a combined molecular dataset, in conjunction with two different molecular dating techniques (penalized likelihood plus a Bayesian approach) and ancestral distribution reconstructions, was used to infer the historical biogeography of these spiders. Trans-Beringian and trans-Atlantic routes appear to account for the present-day distribution of Antrodiaetus in Japan and North America. Future studies on Antrodiaetus phylogeny will be used to address questions regarding morphological stasis and the evolution of quantitative morphological characters.

Animals↗
PubMed2002

Ecology and biogeography of marine parasites.

A review is given of (mainly recent) work on the biodiversity, ecology, biogeography and practical importance of marine parasites. Problems in estimating species numbers have been thoroughly discussed for free-living species, and the main points of these discussions are reviewed here. Even rough estimates of the richness of most parasite groups in the oceans are premature for the following reasons: species numbers of host groups, in particular in the deep sea and the meiofauna, are not known; most host groups have been examined only insufficiently for parasites or not at all; even in some of the best known groups, latitudinal, longitudinal and depth gradients in species richness are only poorly understood or not known at all; effects of hosts on parasite morphology and geographical variation have been studied only in a few cases; there are few studies using techniques of molecular biology to distinguish sibling species. Estimates of species richness in the best known groups, trematodes, monogeneans and copepods of marine fishes, are given. Parasites are found in almost all taxa of eukaryotes, but most parasitic species are concentrated in a few taxa. Important aspects of the ecology of marine parasites are discussed. It is emphasized that host specificity and host ranges should be distinguished, and an index that permits calculation of host specificity is discussed. The same index can be applied to measure site specificity. Central problems in ecology are the importance of interspecific competition and whether equilibrium or non-equilibrium conditions prevail. Marine parasites are among the few groups of organisms that have been extensively examined in this regard. A holistic approach, i.e. application of many methods, has unambiguously shown that metazoan ecto- (and probably endo-) parasites of marine fish live in largely non-saturated niche space under non-equilibrium conditions, i.e. they live in assemblages rather than in communities structured by competition. Nestedness occurs in such assemblages, but it can be explained by characteristics of the species themselves. There is little agreement on which other factors are involved in "structuring" parasite assemblages. Few studies on metapopulations of marine parasites have been made. A new approach, that of fuzzy chaos modelling, is discussed. It is likely that marine parasites are commonly found in metapopulations consisting of many subpopulations, and they are ideally suited to test the predictions of fuzzy chaos. Some recent studies on functional ecology and morphology--especially with regard to host, site and mate finding--are discussed, and attention is drawn to the amazing variety of sensory receptors in some marine parasites. Effects of parasites on hosts, and some studies on the evolution and speciation of marine parasites are discussed as well. A detailed overview of biogeographical studies is given, with respect to latitudinal gradients in species diversity, reproductive strategies and host ranges/specificity. Studies of marine parasites have contributed significantly to giving a non-equilibrium explanation for latitudinal diversity gradients. Recent studies on longitudinal and depth gradients are discussed, as well as parasites in brackish water, parasites as indicators of zoogeographical regions and barriers, and parasites as biological tags. The practical importance of marine parasites in mariculture, as monitors of pollution, agents of human disease, the use of parasites for controlling introduced marine pests, and some related aspects, are also discussed.

Animals↗
PubMed2002

Phylogeny and biogeography of Triatominae (Hemiptera: Reduviidae): molecular evidence of a New World origin of the Asiatic clade.

The most representative sample of molecular data, especially 16S and 12S rDNAs, is used to study the phylogeny and evolution of 57 species of three tribes, Rhodniini, Linshcosteini, and Triatomini, of the subfamily Triatominae. For the first time both New World and Old World species are brought together in a single phylogenetic analysis. Maximum-parsimony and distance estimation place both the Asiatic representatives, Linshcosteus and Triatoma rubrofasciata, as sister groups. The Linshcosteus-T. rubrofasciata clade nests firmly within Triatomini, in most analyses branching as a basalmost lineage, thus supporting a monophyletic origin of Triatominae. A paraphyly of "Triatoma" with respect to Linshcosteus, Dipetalogaster, Eratyrus, and Panstrongylus and the paraphyly of "Rhodnius" with respect to Psammolestes is observed in most of the analyses. Reinterpretation of triatomine biogeography points to the origin of Triatominae in northern areas of South America, in Central America, or in the southern region of North America. A few taxonomic changes are proposed: (1) reinclusion of Linshcosteus in Triatomini, (2) inclusion of Psammolestes in Rhodnius, (3) elevation of the "T. flavida complex" to the full genus Nesotriatoma (including N. flavida, N. bruneri, and N. obscura), (4) inclusion of the "T. spinolai complex" in Mepraia (including M. spinolai, M. gajardoi, M. eratyrusiformis, and M. breyeri), and (5) inclusion of "T." dimidiata in Meccus (M. dimidiatus).

Americas↗
PubMed2003

Biogeography of Japanese wood-feeding cockroaches genus Salganea and Panesthia (Blaberidae: Panesthiinae).

We investigated mitochondrial COII gene sequences of Japanese wood-feeding cockroaches (Salganea spp. and Panesthia angustipennis) in detail to investigate their biogeography. The transition (TI) numbers between each genus north and south of the Tokara Strait, which is a border of the Oriental and the Palaearctic faunal regions, were almost same, but the transversion (TV) numbers were much lower in Panesthia compared with Salganea. These tendencies suggest that multiple substitutions of TIs occurred between certain pairs of Salganea taxa and that the genera must have entered to the north of the Tokara Strait at different times. Phylogenetic relationships and estimated divergence times using TVs divergences suggest that Salganea species and Panesthia taxa north and south of the Tokara Strait were diverged from each other during the latter half of the Miocene and from the late Pliocene to the early Pleistocene, respectively. These two periods are nearly consistent with the two land expanding times in the Ryukyu Islands supported by the recent palaeogeographical hypotheses.

Animals↗
PubMed2004

Molecular phylogeny and biogeography of the Korean woodroaches Cryptocercus spp.

Phylogenetic relationships and biogeography of Northeast Asian Cryptocercus were inferred based on the DNA sequences of mitochondrial COII and 16S rRNA genes and nuclear 18S rRNA gene. The results suggest that two clades exist in Korean populations. The southwestern population (Cryptocercus from Jiri-san) was more closely related to the populations from Northeast China and eastern Russia than to all the other Korean Cryptocercus. According to molecular-based estimated divergence times, the divergence event occurred between Cryptocercus in Jiri-san, Northeast China and eastern Russia and those in the remaining South Korea during the Miocene (7.5-17.4Myr ago), and then the divergence event between Cryptocercus in Jiri-san and those in Northeast China and eastern Russia occurred 0.8-1.9Myr ago. In the Korean Peninsula, Jiri-san is located in the most southwestern region among the high mountains surveyed. The location is the farthest from Northeast China and eastern Russia among sampling localities in South Korea. Thus, it was unexpected that the southwestern populations are more closely related to those from Northeast China and eastern Russia rather than to the other Korean Cryptocercus. Based on Korean topography and estimated divergence times, possible scenarios are proposed for the current geographical distribution of Korean Cryptocercus.

Animals↗