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At least 55 records · Page 3Linked to original sources
PubMed2002

Revealing the faunal tapestry: co-evolution and historical biogeography of hosts and parasites in marine systems.

Parasites are integral components of marine ecosystems, a general observation accepted by parasitologists, but often considered of trifling significance to the broader community of zoologists. Parasites, however, represent elegant tools to explore the origins, distribution and maintenance of biodiversity. Among these diverse assemblages, host and geographic ranges described by various helminths are structured and historically constrained by genealogical and ecological associations that can be revealed and evaluated using phylogenetic methodologies within the context of frameworks and hypotheses for co-evolution and historical biogeography. Despite over 200 years of sporadic investigations of helminth systematics, knowledge of parasite faunal diversity in chondrichthyan and osteichthyan fishes, seabirds and marine mammals remains to be distilled into a coherent and comprehensive picture that can be assessed using phylogenetic approaches. Phylogenetic studies among complex host-parasite assemblages that encompass varying temporal and geographic scales are the critical context for elucidating biodiversity and faunal structure, and for identifying historical and contemporary determinants of ecological organization and biogeographic patterns across the marine biosphere. Insights from phylogenetic inference indicate (1) the great age of marine parasite faunas; (2) a significant role for colonization in diversification across a taxonomic continuum at deep and relatively recent temporal scales; and (3) a primary role for allopatric speciation. Integration of ecological and phylogenetic knowledge from the study of parasites is synergistic, contributing substantial insights into the history and maintenance of marine systems.

Animals↗
PubMed2004

Molecular phylogeny and biogeography of the widely distributed Amanita species, A. muscaria and A. pantherina.

The molecular phylogeny and biogeography of two widely distributed Amanita species, A. muscaria and A. pantherina, were studied based on specimens from diverse localities. Analyses of both a partial sequence of the ITS region of nuclear DNA and a partial sequence of the beta-tubulin gene were able to resolve specimens of each species. Analyses revealed a greater divergence of the beta-tubulin region than the ITS region. Based on molecular phylogeny of the combination of the ITS and beta-tubulin regions, A. muscaria could be separated into at least three groups (Eurasian, Eurasian subalpine, and North American), and A. pantherina could be separated into at least two groups (North American and Eurasian). We hypothesize that the speciation of A. muscaria occurred in Eurasia with subsequent migration to North America via land bridges. However, it is impossible to determine whether A. pantherina moved from Eurasia to North America or vice versa. For both A. muscaria and A. pantherina, the intracontinental relationships of both Eurasia and North America were closer than the relationships between eastern Asia and eastern North America.

Amanita↗
PubMed2001

Population subdivision in marine environments: the contributions of biogeography, geographical distance and discontinuous habitat to genetic differentiation in a blennioid fish, Axoclinus nigricaudus.

The relative importance of factors that may promote genetic differentiation in marine organisms is largely unknown. Here, contributions to population structure from a biogeographic boundary, geographical distance and the distribution of suitable habitat were investigated in Axoclinus nigricaudus, a small subtidal rock-reef fish, throughout its range in the Gulf of California. A 408-bp fragment of the mitochondrial control region was sequenced from 105 individuals. Variation was significantly partitioned between 28 of 36 possible combinations of population pairs. Phylogenetic analyses, hierarchical analyses of variance and a modified Mantel test substantiated a major break between two putative biogeographic regions. This genetic discontinuity coincides with an abrupt change in ecological characteristics, including temperature and salinity, but does not coincide with known oceanographic circulation patterns or any known historic barriers. There was an overall relationship of increasing genetic distance with increasing geographical distance between population pairs, in a manner consistent with isolation-by-distance. A significant habitat-by-geographical-distance interaction term indicated that, for a given geographical distance, populations separated by discontinuous habitat (sand) are more distinct genetically than are populations separated by continuous habitat (rock). In addition, populations separated by deep open waters were more genetically distinct than populations separated by continuous habitat (rock). These results indicate that levels of genetic differentiation among populations of A. nigricaudus cannot be explained by a single factor, but are due to the combined influences of biogeography, geographical distance and availability of suitable habitat.

Animals↗
PubMed2001

Glacial biogeography of North American coho salmon (Oncorhynchus kisutch).

To study the glacial biogeography of coho we examined 20 microsatellite loci and mitochondrial DNA D-loop sequence in samples from Alaska to California. Microsatellite data divided our samples among five biogeographic regions: (1) Alaska and northern coastal British Columbia; (2) the Queen Charlotte Islands; (3) the mainland coast of British Columbia and northern Washington State; (4) the Thompson River; and (5) Oregon and California. The D-loop sequence data suggested three geographical regions: (1) Oregon and California; (2) the Thompson River; and (3) all the other sites north of the southern ice margin. Microsatellite data revealed no difference in the number of alleles in different regions, but mitochondrial DNA data revealed a cline of decreasing diversity from south to north. We suggest that the two signals presented by these different marker types illuminate two time frames in the history of this species. Endemic microsatellite diversity in Alaska and on the Queen Charlotte Islands provides evidence in favour of Fraser Glaciation refugia in these regions. The loss of mitochondrial variation from south to north suggests that one of the earlier, more extensive, Pleistocene glaciations eliminated coho from its northern range.

Alaska↗
PubMed2004

Geography, biogeography, and why some countries are rich and others are poor.

The most important event in human economic history before the industrial revolution was the Neolithic transition from a nomadic hunter-gatherer lifestyle to sedentary agriculture, beginning approximately 10,000 years ago. The transition made possible the human population explosion, the rise of non-food-producing specialists, and the acceleration of technological progress that led eventually to the industrial revolution. But the transition occurred at different times in different regions of the world, with big consequences for the present-day economic conditions of populations indigenous to each region. In this article, we show that differences in biogeographic initial conditions and in geography largely account for the different timings of the Neolithic transition and, thereby, ultimately help account for the 100-fold differences among the prosperity of nations today. The effects of biogeography and geography on the wealth of nations are partly mediated by the quality of present-day institutions but also are partly independent of institutional quality.

Journal Article↗
PubMed2000

Mitochondrial phylogeny of notothenioids: a molecular approach to Antarctic fish evolution and biogeography.

Antarctic waters represent a unique marine environment delimited by an oceanographic barrier, the Polar Front Zone, and characterized by constant subzero temperatures and presence of sea ice. A group of teleost fish, the Notothenioidei, have adapted to these challenging environmental conditions, undergoing a remarkable diversification. In the present study a total of 798 base pairs, generated from partial sequencing of 16S and 12S mitochondrial ribosomal RNA genes, were examined in 33 notothenioid species representative of all families included in the suborder Notothenioidei. Phylogenetic trees, reconstructed on the basis of sequence data by different methods, indicate that traditional hypotheses on notothenioid systematics and biogeography might be in need of reexamination. Molecular evidence suggests that vicariant speciation could be invoked to explain the early divergence of Eleginops maclovinus, a species previously included in the family Nototheniidae, which is now proposed as the closest sister group to all the rest of notothenioids apart from bovichtids. On the other hand, repeated, independent dispersal through the Polar Front is proposed for the divergence of other subantarctic notothenioid species. Likewise, multiple, independent transitions from benthic to pelagic habit are inferred from molecular data, at variance with the more conservative hypothesis based on cladograms reconstructed from morphological data.

Animals↗
PubMed2004

Biogeography explains cophylogenetic patterns in toucan chewing lice.

Historically, comparisons of host and parasite phylogenies have concentrated on cospeciation. However, many of these comparisons have demonstrated that the phylogenies of hosts and parasites are seldom completely congruent, suggesting that phenomena other than cospeciation play an important role in the evolution of host-parasite assemblages. Other coevolutionary phenomena, such as host switching, parasite duplication (speciation on the host), sorting (extinction), and failure to speciate can also influence host-parasite assemblages. Using mitochondrial and nuclear protein-coding DNA sequences, I reconstructed the phylogeny of ectoparasitic toucan chewing lice in the Austrophilopterus cancellosus subspecies complex and compared this phylogeny with the phylogeny of the hosts, the Ramphastos toucans, to reconstruct the history of coevolutionary events in this host-parasite assemblage. Three salient findings emerged. First, reconstructions of host and louse phylogenies indicate that they do not branch in parallel, and their cophylogenetic history shows little or no significant cospeciation. Second, members of monophyletic Austrophilopterus toucan louse lineages are not necessarily restricted to monophyletic host lineages. Often, closely related lice are found on more distantly related but sympatric toucan hosts. Third, the geographic distribution of the hosts apparently plays a role in the speciation of these lice. These results suggest that for some louse lineages biogeography may be more important than host associations in structuring louse populations and species, particularly when host life history (e.g., hole nesting) or parasite life history (e.g., phoresis) might promote frequent host switching events between syntopic host species. These findings highlight the importance of integrating biogeographic information into cophylogenetic studies.

Animals↗
PubMed2005

Biogeography of luminous marine ostracod driven irreversibly by the Japan current.

The biogeography of the luminous marine ostracod Vargula hilgendorfii, also called "Umihotaru," shows that this organism may have arrived relatively recently on the Japanese islands during the final glacier period approximately 10,000 years ago. Phylogenetic relationships also strongly indicate that the Japan Current drove the Umihotaru ostracod northward. It is evident that the Umihotaru ostracod spread rapidly to the major Japanese islands 3,000 km north, whereas its spread was slow in the southwest of the Japanese islands, covering a distance of 400 km. The meandering of the Japan Current, where it passes by the Tokara Gap at 28 degrees N latitude, may be a barrier to Umihotaru ostracod extension.

Animals↗
PubMed2001

Avian evolution, Gondwana biogeography and the Cretaceous-Tertiary mass extinction event.

The fossil record has been used to support the origin and radiation of modern birds (Neornithes) in Laurasia after the Cretaceous-Tertiary mass extinction event, whereas molecular clocks have suggested a Cretaceous origin for most avian orders. These alternative views of neornithine evolution are examined using an independent set of evidence, namely phylogenetic relationships and historical biogeography. Pylogenetic relationships of basal lineages of neornithines, including ratite birds and their allies (Palaleocognathae), galliforms and anseriforms (Galloanserae), as well as lineages of the more advanced Neoves (Gruiformes, (Capimulgiformes, Passeriformes and others) demonstrate pervasive trans-Antarctic distribution patterns. The temporal history of the neornithines can be inferred from fossil taxa and the ages of vicariance events, and along with their biogeographical patterns, leads to the conclusion that neornithines arose in Gondwana prior to the Cretaceous Tertiary extinction event.

Animals↗
PubMed2002

An analysis of dinosaurian biogeography: evidence for the existence of vicariance and dispersal patterns caused by geological events.

As the supercontinent Pangaea fragmented during the Mesozoic era, dinosaur faunas were divided into isolated populations living on separate continents. It has been predicted, therefore, that dinosaur distributions should display a branching ('vicariance') pattern that corresponds with the sequence and timing of continental break-up. Several recent studies, however, minimize the importance of plate tectonics and instead suggest that dispersal and regional extinction were the main controls on dinosaur biogeography. Here, in order to test the vicariance hypothesis, we apply a cladistic biogeographical method to a large dataset on dinosaur relationships and distributions. We also introduce a methodological refinement termed 'time-slicing', which is shown to be a key step in the detection of ancient biogeographical patterns. These analyses reveal biogeographical patterns that closely correlate with palaeogeography. The results provide the first statistically robust evidence that, from Middle Jurassic to mid-Cretaceous times, tectonic events had a major role in determining where and when particular dinosaur groups flourished. The fact that evolutionary trees for extinct organisms preserve such distribution patterns opens up a new and fruitful direction for palaeobiogeographical research.

Animals↗
PubMed2004

Historical biogeography of two cosmopolitan families of flowering plants: Annonaceae and Rhamnaceae.

Annonaceae are a pantropically distributed family found predominantly in rainforests, so they are megathermal taxa, whereas Rhamnaceae are a cosmopolitan family that tend to be found in xeric regions and may be classified as mesothermal. Phylogenetic analyses of these families are presented based on rbcL and trnL-F plastid DNA sequences. Likelihood ratio tests revealed rate heterogeneity in both phylogenetic trees and they were therefore made ultrametric using non-parametric rate smoothing and penalized likelihood. Divergence times were then estimated using fossil calibration points. The historical biogeography of these families that are species rich in different biomes is discussed and compared with other published reconstructions. Rhamnaceae and most lineages within Annonaceae are too young to have had their distribution patterns influenced by break-up of previously connected Gondwanan landmasses. Contrasts in the degree of geographical structure between these two families may be explained by differences in age and dispersal capability. In both groups, long-distance dispersal appears to have played a more significant role in establishing modern patterns than had previously been assumed. Both families also contain examples of recent diversification of species-rich lineages. An understanding of the processes responsible for shaping the distribution patterns of these families has contributed to our understanding of the historical assembly of the biomes that they occupy.

Annonaceae↗
PubMed2001

Phylogenetic relationships of flaviviruses correlate with their epidemiology, disease association and biogeography.

Phylogenetic analysis of the Flavivirus genus, using either partial sequences of the non-structural 5 gene or the structural envelope gene, revealed an extensive series of clades defined by their epidemiology and disease associations. These phylogenies identified mosquito-borne, tick-borne and no-known-vector (NKV) virus clades, which could be further subdivided into clades defined by their principal vertebrate host. The mosquito-borne flaviviruses revealed two distinct epidemiological groups: (i) the neurotropic viruses, often associated with encephalitic disease in humans or livestock, correlated with the Culex species vector and bird reservoirs and (ii) the non-neurotropic viruses, associated with haemorrhagic disease in humans, correlated with the Aedes species vector and primate hosts. Thus, the tree topology describing the virus-host association may reflect differences in the feeding behaviour between Aedes and Culex mosquitoes. The tick-borne viruses also formed two distinct groups: one group associated with seabirds and the other, the tick-borne encephalitis complex viruses, associated primarily with rodents. The NKV flaviviruses formed three distinct groups: one group, which was closely related to the mosquito-borne viruses, associated with bats; a second group, which was more genetically distant, also associated with bats; and a third group associated with rodents. Each epidemiological group within the phylogenies revealed distinct geographical clusters in either the Old World or the New World, which for mosquito-borne viruses may reflect an Old World origin. The correlation between epidemiology, disease correlation and biogeography begins to define the complex evolutionary relationships between the virus, vector, vertebrate host and ecological niche.

Aedes↗
PubMedDate not supplied

Pattern identification in biogeography.

Identifying common patterns among area cladograms that arise in historical biogeography is an important tool for biogeographical inference. We develop the first rigorous formalization of these pattern-identification problems. We develop metrics to compare area cladograms. We define the maximum agreement area cladogram (MAAC) and we develop efficient algorithms for finding the MAAC of two area cladograms, while showing that it is NP-hard to find the MAAC of several binary area cladograms. We also describe a linear-time algorithm to identify if two area cladograms are identical.

Algorithms↗
PubMed2002

Phylogeny of Acridocarpus-Brachylophon (Malpighiaceae): implications for tertiary tropical floras and Afroasian biogeography.

A major tenet of African Tertiary biogeography posits that lowland rainforest dominated much of Africa in the late Cretaceous and was replaced by xeric vegetation as a response to continental uplift and consequent widespread aridification beginning in the late Paleogene. The aridification of Africa is thought to have been a major factor in the extinction of many African humid-tropical lineages, and in the present-day disparity of species diversity between Africa and other tropical regions. This primarily geologically based model can be tested with independent phylogenetic evidence from widespread African plant groups containing both humid- and xeric-adapted species. We estimated the phylogeny and lineage divergence times within one such angiosperm group, the acridocarpoid clade (Malpighiaceae), with combined ITS, ndhF, and trnL-F data from 15 species that encompass the range of morphological and geographic variation within the group. Dispersal-vicariance analysis and divergence-time estimates suggest that the basal acridocarpoid divergence occurred between African and Southeast Asian lineages approximately 50 million years ago (mya), perhaps after a southward ancestral retreat from high-latitude tropical forests in response to intermittent Eocene cooling. Dispersion of Aeridocarpus from Africa to Madagascar is inferred between approximately 50 and 35 mya, when lowland humid tropical forest was nearly continuous between these landmasses. A single dispersal event within Acridocarpus is inferred from western Africa to eastern Africa between approximately 23 and 17 mya, coincident with the widespread replacement of humid forests by savannas in eastern Africa. Although the spread of xeric environments resulted in the extinction of many African plant groups, our data suggest that for others it provided an opportunity for further diversification.

Africa↗
PubMed2002

The historical biogeography of two Caribbean butterflies (Lepidoptera: Heliconiidae) as inferred from genetic variation at multiple loci.

Mitochondrial DNA and allozyme variation was examined in populations of two Neotropical butterflies, Heliconius charithonia and Dryas iulia. On the mainland, both species showed evidence of considerable gene flow over huge distances. The island populations, however, revealed significant genetic divergence across some, but not all, ocean passages. Despite the phylogenetic relatedness and broadly similar ecologies of these two butterflies, their intraspecific biogeography clearly differed. Phylogenetic analyses of mitochondrial DNA sequences revealed that populations of D. iulia north of St. Vincent are monophyletic and were probably derived from South America. By contrast, the Jamaican subspecies of H. charithonia rendered West Indian H. charithonia polyphyletic with respect to the mainland populations; thus, H. charithonia seems to have colonized the Greater Antilles on at least two separate occasions from Central America. Colonization velocity does not correlate with subsequent levels of gene flow in either species. Even where range expansion seems to have been instantaneous on a geological timescale, significant allele frequency differences at allozyme loci demonstrate that gene flow is severely curtailed across narrow ocean passages. Stochastic extinction, rapid (re)colonization, but low gene flow probably explain why, in the same species, some islands support genetically distinct and nonexpanding populations, while nearby a single lineage is distributed across several islands. Despite the differences, some common biogeographic patterns were evident between these butterflies and other West Indian taxa; such congruence suggests that intraspecific evolution in the West Indies has been somewhat constrained by earth history events, such as changes in sea level.

Animals↗
PubMed2002

Historical biogeography of the livebearing fish genus Poeciliopsis (Poeciliidae: Cyprinodontiformes).

To assess the historical biogeography of freshwater topminnows in the genus Poeciliopsis, we examined sequence variation in two mitochondrial genes, cytochrome b (1140 bp) and NADH subunit 2 (1047 bp). This widespread fish genus is distributed from Arizona to western Colombia, and nearly half of its 21 named species have distributions that border on the geologically active Trans-Mexican Volcanic Belt (TMVB), a region that defines the uplifted plateau (Mesa Central) of Mexico. We used the parametric bootstrap method to test the hypothesis that a single vicariant event associated with the TMVB was responsible for divergence of taxa found to the north and south of this boundary. Because the single-event hypothesis was rejected as highly unlikely, we hypothesize that at least two geological events were responsible for divergence of these species. The first (8-16 million years ago) separated ancestral populations that were distributed across the present TMVB region. A second event (2.8-6.4 million years ago) was associated with northward dispersal and subsequent vicariance of two independent southern lineages across the TMVB. The geological history of this tectonically and volcanically active region is discussed and systematic implications for the genus are outlined.

Animals↗
PubMed2006

Breeding birds on small islands: island biogeography or optimal foraging?

1. We test MacArthur and Wilson's theory about the biogeography of communities on isolated habitat patches using bird breeding records from 16 small islands off the coasts of Britain and Ireland. 2. A traditional examination of patterns of species richness on these islands suggests that area and habitat diversity are important predictors, but that isolation and latitude have a negligible impact in this system. 3. Unlike traditional studies, we directly examine the fundamental processes of colonization and local extinction (cessation of breeding), rather than higher-order phenomena such as species richness. 4. We find that many of MacArthur and Wilson's predictions hold: colonization probability is lower on more isolated islands, and extinction probability is lower on larger islands and those with a greater diversity of habitats. 5. We also find an unexpected pattern: extinction probability is much lower on more isolated islands. This is the strongest relationship in these data, and isolation is the best single predictor of colonization and extinction. 6. Our results show that examination of species richness alone is misleading. Isolation has a strong effect on both of the dynamic processes that underlie richness, and in this system, the reductions in both colonization and extinction probability seen on more distant islands have opposing influences on species richness, and largely cancel each other out. 7. We suggest that an appropriate model for this system might be optimal foraging theory, which predicts that organisms will stay longer in a resource patch if the distance to a neighbouring patch is large. If nest sites and food are the resources in this system, then optimal foraging theory predicts the pattern we observe. 8. We advance the hypothesis that there is a class of spatial systems, defined by their scale and by the taxon under consideration, at which decision-making processes are a key driver of the spatiotemporal dynamics. The appropriate theory for such systems will be a hybrid of concepts from biogeography/metapopulation theory and behavioural ecology.

Animals↗
PubMed2005

Mitochondrial DNA phylogeography of the Mesoamerican spiny-tailed lizards (Ctenosaura quinquecarinata complex): historical biogeography, species status and conservation.

Through the examination of past and present distributions of plants and animals, historical biogeographers have provided many insights on the dynamics of the massive organismal exchange between North and South America. However, relatively few phylogeographic studies have been attempted in the land bridge of Mesoamerica despite its importance to better understand the evolutionary forces influencing this biodiversity 'hotspot'. Here we use mitochondrial DNA sequence data from fresh samples and formalin-fixed museum specimens to investigate the genetic and biogeographic diversity of the threatened Mesoamerican spiny-tailed lizards of the Ctenosaura quinquecarinata complex. Species boundaries and their phylogeographic patterns are examined to better understand their disjunct distribution. Three monophyletic, allopatric lineages are established using mtDNA phylogenetic and nested clade analyses in (i) northern: México, (ii) central: Guatemala, El Salvador and Honduras, and (iii) southern: Nicaragua and Costa Rica. The average sequence divergence observed between lineages varied between 2.0% and 3.7% indicating that they do not represent a very recent split and the patterns of divergence support the recently established nomenclature of C. quinquecarinata, Ctenosaura flavidorsalis and Ctenosaura oaxacana. Considering the geological history of Mesoamerica and the observed phylogeographic patterns of these lizards, major evolutionary episodes of their radiation in Mesoamerica are postulated and are indicative of the regions' geological complexity. The implications of these findings for the historical biogeography, taxonomy and conservation of these lizards are discussed.

Animals↗