Origin, elevation, and evolutionary success of hybrids and polyploids in British Columbia, Canada

Botany ◽  
2013 ◽  
Vol 91 (3) ◽  
pp. 182-188 ◽  
Author(s):  
Jana C. Vamosi ◽  
Jamie R. McEwen
Keyword(s):  
British Columbia ◽  
Evolutionary History ◽  
Elevation Gradient ◽  
Hybrid Origin ◽  
Diploid Hybrid ◽  
Hybrid Species ◽  
Ecological Patterns ◽  
Evolutionary Success ◽  
Richness Patterns ◽  
High Elevations

Although it is well established that many clades have polyploidization in their evolutionary history, the question of whether polyploidization is actually adaptive is far from resolved. It has been hypothesized that the evolutionary advantages of polyploidy are context-dependent, although we have yet to clearly identify the geographical or ecological contexts in which polyploids are more common. One reason why polyploidy may be displaying idiosyncratic ecological patterns is that previous comparative studies have often not separated polyploids into allopolyploids and autopolyploids, and we posit that there may be important differences in the origin and evolutionary success between the two types. Here, we examine the distribution of allopolyploid, autopolyploid, and diploid hybrid species along an elevation gradient from sea level to ∼4500 m within British Columbia, Canada, and find that polyploids (especially those of hybrid origin) are disproportionately present at high elevations. These processes of hybridization and polyploidization may contribute to species richness patterns observed in British Columbia. We discuss whether the associations are more likely to be the result of differential ecological tolerance or differential origination rates of allopolyploids at higher elevations. These findings highlight the importance of studying both hybridization and polyploidy when considering the diversification process in plants.

scholarly journals New glacier evidence for ice-free summits during the life of the Tyrolean Iceman

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Pascal Bohleber ◽  
Margit Schwikowski ◽  
Martin Stocker-Waldhuber ◽  
Ling Fang ◽  
Andrea Fischer
Keyword(s):  
Elevation Gradient ◽  
Ice Age ◽  
Detailed Knowledge ◽  
New Approach ◽  
Radiocarbon Age ◽  
Alpine Glaciers ◽  
The Alps ◽  
Tyrolean Iceman ◽  
High Elevations ◽  
Age Constraints

AbstractDetailed knowledge of Holocene climate and glaciers dynamics is essential for sustainable development in warming mountain regions. Yet information about Holocene glacier coverage in the Alps before the Little Ice Age stems mostly from studying advances of glacier tongues at lower elevations. Here we present a new approach to reconstructing past glacier low stands and ice-free conditions by assessing and dating the oldest ice preserved at high elevations. A previously unexplored ice dome at Weißseespitze summit (3500 m), near where the “Tyrolean Iceman” was found, offers almost ideal conditions for preserving the original ice formed at the site. The glaciological settings and state-of-the-art micro-radiocarbon age constraints indicate that the summit has been glaciated for about 5900 years. In combination with known maximum ages of other high Alpine glaciers, we present evidence for an elevation gradient of neoglaciation onset. It reveals that in the Alps only the highest elevation sites remained ice-covered throughout the Holocene. Just before the life of the Iceman, high Alpine summits were emerging from nearly ice-free conditions, during the start of a Mid-Holocene neoglaciation. We demonstrate that, under specific circumstances, the old ice at the base of high Alpine glaciers is a sensitive archive of glacier change. However, under current melt rates the archive at Weißseespitze and at similar locations will be lost within the next two decades.

scholarly journals Going Coastal: Shared Evolutionary History between Coastal British Columbia and Southeast Alaska Wolves (Canis lupus)

PLoS ONE ◽  
2011 ◽  
Vol 6 (5) ◽  
pp. e19582 ◽  
Author(s):  
Byron V. Weckworth ◽  
Natalie G. Dawson ◽  
Sandra L. Talbot ◽  
Melanie J. Flamme ◽  
Joseph A. Cook
Keyword(s):  
British Columbia ◽  
Canis Lupus ◽  
Evolutionary History ◽  
Southeast Alaska ◽  
Coastal British Columbia

Speciation by hybridization in phasmids and other insects

1990 ◽  
Vol 68 (8) ◽  
pp. 1747-1760 ◽  
Author(s):  
Luciano Bullini ◽  
Giuseppe Nascetti
Keyword(s):  
Hybrid Origin ◽  
Clonal Variation ◽  
Female Reproduction ◽  
Bisexual Species ◽  
Hybrid Species ◽  
Carausius Morosus ◽  
Origin And Evolution ◽  
Parthenogenetic Development ◽  
Hybrid Genome ◽  
Disturbed Habitats

Speciation by hybridization in insects has been recently recognized on the basis of isozyme and chromosome studies showing that several species, either diploid or polyploid, have genomes that combine the genes and chromosome sets of two (or more) bisexual species. Until this evidence became available, thelytokous invertebrates were all considered uniparental derivatives of bisexual species. In this paper, we review examples including the stick insects Bacillus whitei, B. atticus, B. lynceorum, Leptynia hispanica D, Clonopsis gallica, Carausius morosus; the grasshopper Warramaba virgo; some Otiorrhynchus weevils; the planthopper Muellerianella 2-fairmairei–brevipennis; and black flies of the genera Gymnopais and Prosimulium. For several species (e.g., Warramaba virgo and Bacillus whitei), both parental taxa have been recognized, and their hybrid origin has been genetically assessed. In others (e.g., B. atticus), only one of the bisexual parental species has been detected; but their hybrid origin is supported by strong evidence, at both the isozyme and chromosome levels. For other supposed hybrid species (e.g., Clonopsis gallica, Carausius morosus), no bisexual ancestors have been detected, possibly because competition with their hybrid derivatives has made them rare or extinct. Insect hybrid species may differ in their mode of reproduction (apomictic or automictic thelytokous parthenogenesis, gynogenesis), degree of ploidy, and genetic structure (level of heterozygosity, clonal variation). The parallels between insect and vertebrate hybrid species, in which this phenomenon has been recognized and widely studied in the past 50 years, are drawn. The main problems involved in the origin and evolution of hybrid species are discussed, with particular regard to (i) changes in the maturation divisions allowing the transmission of the hybrid genome to the next generation, and (ii) their successful adaptation. The "spontaneous" and "hybrid" theories for the origin of unisexual forms are compared, with regard to hybrid species. An origin of hybrid species from occasional parthenogenetic development of hybrid eggs produced in areas of extensive interspecific hybridization (e.g., disturbed habitats) is suggested. Hybridization would not itself cause changes in the maturation divisions (which are controlled by genes of tychoparthenogenetic eggs) but only favour their selection through heterosis. The role of the so-called "heterotic" advantage (resulting from high levels of heterozygosity) and "demographic" advantage (resulting from all-female reproduction) in the evolutionary success of hybrid species is discussed. It is concluded that habitat disturbance by man is favouring both the onset of hybrid species and their successful spread.

Evolutionary history of Purple cone spruce (Picea purpurea) in the Qinghai-Tibet Plateau: homoploid hybrid origin and Pleistocene expansion

2013 ◽  
Vol 23 (2) ◽  
pp. 343-359 ◽  
Author(s):  
Yongshuai Sun ◽  
Richard J. Abbott ◽  
Lili Li ◽  
Long Li ◽  
Jiabin Zou ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Hybrid Origin ◽  
Tibet Plateau ◽  
History Of ◽  
Homoploid Hybrid ◽  
Qinghai Tibet Plateau

Evolutionary history of threespine sticklebacks (Gasterosteus spp.) in British Columbia: insights from a physiological clock

1995 ◽  
Vol 73 (11) ◽  
pp. 2154-2158 ◽  
Author(s):  
Rees Kassen ◽  
Dolph Schluter ◽  
John Donald McPhail
Keyword(s):  
British Columbia ◽  
Fresh Water ◽  
Evolutionary History ◽  
Egg Size ◽  
Gasterosteus Aculeatus ◽  
Salt Water ◽  
Freshwater Invasion ◽  
Freshwater Population ◽  
Threespine Sticklebacks ◽  
History Of

Geologic and allozyme evidence suggests that threespine sticklebacks (Gasterosteus aculeatus complex) in low-lying southwestern British Columbia lakes were founded during two incursions of marine sticklebacks after the retreat of the Pleistocene glaciers (the double-invasion hypothesis). We used the salinity tolerance of embryos, measured as hatchability in salt water, to establish the relative order of freshwater invasion by marine sticklebacks and to test the double-invasion hypothesis. Limnetics and an anadromous population hatched nearly equivalent numbers of young in salt water as in fresh water, whereas benthics and one solitary freshwater population had low hatchability in salt water. We also found that eggs from freshwater populations were larger than those from marine populations and limnetics had smaller eggs than benthics and the solitary population. These results support the double-invasion hypothesis and suggest a trend of increasing egg size with increasing time spent in fresh water.

Hybrid Origin and Genomic Mosaicism of Dubautia scabra (Hawaiian Silversword Alliance; Asteraceae, Madiinae)

2008 ◽  
Vol 33 (3) ◽  
pp. 589-597 ◽  
Author(s):  
Elizabeth A. Friar ◽  
Linda M. Prince ◽  
Jennifer M. Cruse-Sanders ◽  
Mitchell E. McGlaughlin ◽  
Charles A. Butterworth ◽  
...  
Keyword(s):  
Single Copy ◽  
Nuclear Genes ◽  
Hybrid Origin ◽  
Internal Transcribed Spacer Region ◽  
Hybrid Species ◽  
Cytogenetic Data ◽  
Molecular Phylogenetic ◽  
Distinct Lineage ◽  
Phylogenetic Hypotheses ◽  
Genomic Regions

Incongruence among different estimates of species relationships in plants, from different molecules, cytogenetic data, biogeographic data, morphological/anatomical data or other sources, has been used frequently as an indication of introgression, hybrid species origin, or chloroplast (cp) capture. In plants, these incongruences are most often seen between data derived from the nuclear vs. the cp genomes and the nuclear markers used for comparison usually have been from the nuclear ribosomal (nr) internal transcribed spacer region (ITS). The amount of genomic material shared between introgressing species can be highly variable. In some of these cases, other nuclear genomic regions have moved between species without leaving a signature on the nrITS. An example of well-supported phylogenetic incongruence is the placement of Dubautia scabra (DC.) D. D. Keck in the Hawaiian silversword alliance (HSA); evolutionary hypotheses for D. scabra based on molecular as opposed to cytogenetic data are strongly discordant. In this paper, we test these two conflicting phylogenetic hypotheses regarding the evolutionary relationships of Dubautia scabra using evidence from six low-copy nuclear genes, as well as multiple chloroplast noncoding regions and nrITS. The nrITS region is also examined for the presence of multiple copy types. Incongruence between inferred relationships based on nuclear chromosomal arrangements and molecular phylogenetic data from chloroplast DNA and nrITS is resolved in favor of a hypothesis of ancient hybridization rather than cytogenetic homoplasy involving dysploidy. Most single-copy nuclear genes track histories of D. scabra compatible with cytogenetic data whereas chloroplast and nrITS data track a common, different history that appears to reflect hybridization with a chromosomally distinct lineage that also occurs on Maui Nui and Hawai'i (the Big Island).

scholarly journals Separate F-Type Plasmids Have Shaped the Evolution of the H30 Subclone of Escherichia coli Sequence Type 131

mSphere ◽  
2016 ◽  
Vol 1 (4) ◽  
Author(s):  
Timothy J. Johnson ◽  
Jessica L. Danzeisen ◽  
Bonnie Youmans ◽  
Kyle Case ◽  
Katharine Llop ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Real Time ◽  
Single Molecule ◽  
Convergent Evolution ◽  
Evolutionary History ◽  
Gene Clusters ◽  
Content Type ◽  
E Coli ◽  
History Of ◽  
Evolutionary Success

ABSTRACT A clonal lineage of Escherichia coli known as ST131 has emerged as a dominating strain type causing extraintestinal infections in humans. The evolutionary history of ST131 E. coli is now well understood. However, the role of plasmids in ST131’s evolutionary history is poorly defined. This study utilized real-time, single-molecule sequencing to compare plasmids from various current and historical lineages of ST131. From this work, it was determined that a series of plasmid gains, losses, and recombinational events has led to the currently circulating plasmids of ST131 strains. These plasmids appear to have evolved to acquire similar gene clusters on multiple occasions, suggesting possible plasmid-mediated convergent evolution leading to evolutionary success. These plasmids also appear to be better suited to exist in specific strains of ST131 due to coadaptive mutations. Overall, a series of events has enabled the evolution of ST131 plasmids, possibly contributing to the lineage’s success. The extraintestinal pathogenic Escherichia coli (ExPEC) H30 subclone of sequence type 131 (ST131-H30) has emerged abruptly as a dominant lineage of ExPEC responsible for human disease. The ST131-H30 lineage has been well described phylogenetically, yet its plasmid complement is not fully understood. Here, single-molecule, real-time sequencing was used to generate the complete plasmid sequences of ST131-H30 isolates and those belonging to other ST131 clades. Comparative analyses revealed separate F-type plasmids that have shaped the evolution of the main fluoroquinolone-resistant ST131-H30 clades. Specifically, an F1:A2:B20 plasmid is strongly associated with the H30R/C1 clade, whereas an F2:A1:B− plasmid is associated with the H30Rx/C2 clade. A series of plasmid gene losses, gains, and rearrangements involving IS26 likely led to the current plasmid complements within each ST131-H30 sublineage, which contain several overlapping gene clusters with putative functions in virulence and fitness, suggesting plasmid-mediated convergent evolution. Evidence suggests that the H30Rx/C2-associated F2:A1:B− plasmid type was present in strains ancestral to the acquisition of fluoroquinolone resistance and prior to the introduction of a multidrug resistance-encoding gene cassette harboring bla CTX-M-15. In vitro experiments indicated a host strain-independent low frequency of plasmid transfer, differential levels of plasmid stability even between closely related ST131-H30 strains, and possible epistasis for carriage of these plasmids within the H30R/Rx lineages. IMPORTANCE A clonal lineage of Escherichia coli known as ST131 has emerged as a dominating strain type causing extraintestinal infections in humans. The evolutionary history of ST131 E. coli is now well understood. However, the role of plasmids in ST131’s evolutionary history is poorly defined. This study utilized real-time, single-molecule sequencing to compare plasmids from various current and historical lineages of ST131. From this work, it was determined that a series of plasmid gains, losses, and recombinational events has led to the currently circulating plasmids of ST131 strains. These plasmids appear to have evolved to acquire similar gene clusters on multiple occasions, suggesting possible plasmid-mediated convergent evolution leading to evolutionary success. These plasmids also appear to be better suited to exist in specific strains of ST131 due to coadaptive mutations. Overall, a series of events has enabled the evolution of ST131 plasmids, possibly contributing to the lineage’s success.

scholarly journals Diversification in Monkeyflowers: An Investigation of the Effects of Elevation and Floral Color in the Genus Mimulus

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Ezgi Ogutcen ◽  
Brooklyn Hamper ◽  
Jana C. Vamosi
Keyword(s):  
High Elevation ◽  
Flowering Plant ◽  
Floral Colour ◽  
Transition Rates ◽  
Extinction Rates ◽  
Floral Color ◽  
Speciation Rates ◽  
Evolutionary Success ◽  
Plant Families ◽  
High Elevations

The vast diversity of floral colours in many flowering plant families, paired with the observation of preferences among pollinators, suggests that floral colour may be involved in the process of speciation in flowering plants. While transitions in floral colour have been examined in numerous genera, we have very little information on the consequences of floral colour transitions to the evolutionary success of a clade. Overlaid upon these patterns is the possibility that certain floral colours are more prevalent in certain environments, with the causes of differential diversification being more directly determined by geographical distribution. Here we examine transition rates to anthocyanin + carotenoid rich (red/orange/fuschia) flowers and examine whether red/orange flowers are associated with differences in speciation and/or extinction rates in Mimulus. Because it has been suggested that reddish flowers are more prevalent at high elevation, we also examine the macroevolutionary evidence for this association and determine if there is evidence for differential diversification at high elevations. We find that, while red/orange clades have equivalent speciation rates, the trait state of reddish flowers reverts more rapidly to the nonreddish trait state. Moreover, there is evidence for high speciation rates at high elevation and no evidence for transition rates in floral colour to differ depending on elevation.

scholarly journals Evidence for continual hybridization rather than hybrid speciation betweenLigularia duciformisandL. paradoxa(Asteraceae)

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3884 ◽  
Author(s):  
Rong Zhang ◽  
Xun Gong ◽  
Ryan Folk
Keyword(s):  
Parental Species ◽  
Reproductive Traits ◽  
Issr Markers ◽  
Natural Hybridization ◽  
Hybrid Origin ◽  
Phenotypic Traits ◽  
Hybrid Species ◽  
Network Analyses ◽  
Hybrid Swarms ◽  
Ssr Loci

BackgroundHybrids possess phenotypic traits that are often intermediate between their parental taxa, which commonly serves as evidence of hybridization in morphological analyses. Natural hybridization has been shown to occur frequently inLigularia(Asteraceae). In a previous study,Ligularia×maoniushanensiswas demonstrated as a natural hybrid species betweenL. duciformisandL.paradoxabased on morphological and reproductive traits.MethodsWe used three chloroplast (cpDNA) fragments (psbA-trnH,trnL-rpl32 andtrnQ-5′rps16), the nuclear ribosomal internal transcribed spacer (nrITS), and co-dominant SSR and dominant ISSR markers to study natural hybridization betweenL. duciformisandL. paradoxagrowing sympatrically in two locations. Parental taxa were inferred using network analyses of cpDNA and nrITS haplotypes. Admixture among individuals was examined using the Bayesian clustering programs STRUCTURE and NewHybrids based on the SSR and ISSR data; and potential introgression in the SSR loci was assessed using the INTROGRESS package.ResultsThe putative parental species were clearly distinguished from other sympatricLigulariaspecies by nrITS data, andL.×maoniushanensisindividuals were confirmed to be the hybrid offspring ofL.duciformisandL.paradoxa. Moreover, introgression was detected among several individuals morphologically identified asL.duciformisorL. paradoxa. Analyses of the cpDNA data revealed primarily unidirectional hybridization betweenL. duciformisandL. paradoxa, withL.paradoxaas the maternal parent in Mt. Maoniu, whereas bidirectional but asymmetrical hybridization was inferred to occur in Heihai Lake. The STRUCTURE analyses based on the SSR data detected two distinct clusters among the three taxa. The NewHybrids analyses showed that individuals circumscribed asL.×maoniushanensiswere dominated by early- and later-generation and backcrossing hybrids. The NewHybrids results based on the ISSR data were congruent with SSR results. In addition, introgression was detected in some SSR loci, and heterogeneity among loci was found in terms of detected patterns of introgression.ConclusionsOur data provide strong evidence for hybridization and introgression betweenL.duciformisandL.paradoxa.Ligularia×maoniushanensiswas demonstrated to be of hybrid origin. Since no evident reproductive isolation was found between the two parental species, detected hybrids appear to be part of hybrid swarms resulting from frequent and ongoing gene flow, which might impede the formation of a new hybrid species.

Sign in / Sign up

Export Citation Format

Share Document