1
|
Pfeilsticker TR, Jones RC, Steane DA, Vaillancourt RE, Potts BM. Molecular insights into the dynamics of species invasion by hybridisation in Tasmanian eucalypts. Mol Ecol 2023; 32:2913-2929. [PMID: 36807951 DOI: 10.1111/mec.16892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/26/2022] [Accepted: 01/26/2023] [Indexed: 02/22/2023]
Abstract
In plants where seed dispersal is limited compared with pollen dispersal, hybridisation may enhance gene exchange and species dispersal. We provide genetic evidence of hybridisation contributing to the expansion of the rare Eucalyptus risdonii into the range of the widespread Eucalyptus amygdalina. These closely related tree species are morphologically distinct, and observations suggest that natural hybrids occur along their distribution boundaries and as isolated trees or in small patches within the range of E. amygdalina. Hybrid phenotypes occur outside the range of normal dispersal for E. risdonii seed, yet in some hybrid patches small individuals resembling E. risdonii occur and are hypothesised to be a result of backcrossing. Using 3362 genome-wide SNPs assessed from 97 individuals of E. risdonii and E. amygdalina and 171 hybrid trees, we show that (i) isolated hybrids match the genotypes expected of F1 /F2 hybrids, (ii) there is a continuum in the genetic composition among the isolated hybrid patches from patches dominated by F1 /F2 -like genotypes to those dominated by E. risdonii-backcross genotypes, and (iii) the E. risdonii-like phenotypes in the isolated hybrid patches are most-closely related to proximal larger hybrids. These results suggest that the E. risdonii phenotype has been resurrected in isolated hybrid patches established from pollen dispersal, providing the first steps in its invasion of suitable habitat by long-distance pollen dispersal and complete introgressive displacement of E. amygdalina. Such expansion accords with the population demographics, common garden performance data, and climate modelling which favours E. risdonii and highlights a role of interspecific hybridisation in climate change adaptation and species expansion.
Collapse
Affiliation(s)
- Thais R Pfeilsticker
- School of Natural Sciences and ARC Training Centre for Forest Value, University of Tasmania, Hobart, Tasmania, Australia
| | - Rebecca C Jones
- School of Natural Sciences and ARC Training Centre for Forest Value, University of Tasmania, Hobart, Tasmania, Australia
| | - Dorothy A Steane
- School of Natural Sciences and ARC Training Centre for Forest Value, University of Tasmania, Hobart, Tasmania, Australia
| | - René E Vaillancourt
- School of Natural Sciences and ARC Training Centre for Forest Value, University of Tasmania, Hobart, Tasmania, Australia
| | - Brad M Potts
- School of Natural Sciences and ARC Training Centre for Forest Value, University of Tasmania, Hobart, Tasmania, Australia
| |
Collapse
|
2
|
Multiple Recent Colonizations of the Australian Region by the Chydorus sphaericus Group (Crustacea: Cladocera). WATER 2022. [DOI: 10.3390/w14040594] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Biotic introductions are an ongoing disruption for many ecosystems. For passively dispersed freshwater zooplankton, transcontinental introductions have been common but are poorly studied in the southern hemisphere. Here we assess the hypothesis of recent introduction for populations of the Chydorus sphaericus group (Crustacea: Cladocera) in Australia. We analyzed 254 sequences (63 original sequences) from the cytochrome oxidase I region of mitochondrial DNA of Chydorus sp., which included global representation. Three Australian populations were connected with separate clades in the northern hemisphere, suggesting multiple colonization events for Australia. The timescale of the divergences was consistent with recent (Quaternary) dispersal. As Australian populations are exposed to migrating birds from the northern hemisphere, both avian and anthropogenic sources are candidates for dispersal vectors. We concluded that recent cross-hemisphere dispersal in the Chydorus sphaericus group is more common than previously believed.
Collapse
|
3
|
Li
X, Wei G, El-Kassaby YA, Fang Y. Hybridization and introgression in sympatric and allopatric populations of four oak species. BMC PLANT BIOLOGY 2021; 21:266. [PMID: 34107871 PMCID: PMC8188795 DOI: 10.1186/s12870-021-03007-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 05/05/2021] [Indexed: 05/28/2023]
Abstract
BACKGROUND Hybridization and introgression are vital sources of novel genetic variation driving diversification during reticulated evolution. Quercus is an important model clade, having extraordinary diverse and abundant members in the Northern hemisphere, that are used to studying the introgression of species boundaries and adaptive processes. China is the second-largest distribution center of Quercus, but there are limited studies on introgressive hybridization. RESULTS Here, we screened 17 co-dominant nuclear microsatellite markers to investigate the hybridization and introgression of four oaks (Quercus acutissima, Quercus variabilis, Quercus fabri, and Quercus serrata) in 10 populations. We identified 361 alleles in the four-oak species across 17 loci, and all loci were characterized by high genetic variability (HE = 0.844-0.944) and moderate differentiation (FST = 0.037-0.156) levels. A population differentiation analysis revealed the following: allopatric homologous (FST = 0.064) < sympatric heterogeneous (FST = 0.071) < allopatric heterogeneous (FST = 0.084). A Bayesian admixture analysis determined four types of hybrids (Q. acutissima × Q. variabilis, Q. fabri × Q. serrata, Q. acutissima × Q. fabri, and Q. acutissima × Q. variabilis × Q. fabri) and their asymmetric introgression. Our results revealed that interspecific hybridization is commonly observed within the section Quercus, with members having tendency to hybridize. CONCLUSIONS Our study determined the basic hybridization and introgression states among the studied four oak species and extended our understanding of the evolutionary role of hybridization. The results provide useful theoretical data for formulating conservation strategies.
Collapse
Affiliation(s)
- Xuan Li
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Key Laboratory of State Forestry and Grassland Administration On Subtropical Forest Biodiversity Conservation, Nanjing Forestry University, 159 Longpan Road, Nanjing, 210037 PR China
- Department of Forest and Conservation Sciences Faculty of Forestry, The University of British Columbia, 2424 Main Mall, Vancouver, BC V6T 1Z4 Canada
| | - Gaoming Wei
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Key Laboratory of State Forestry and Grassland Administration On Subtropical Forest Biodiversity Conservation, Nanjing Forestry University, 159 Longpan Road, Nanjing, 210037 PR China
- School of Physics and Electronics Henan University, Jinming Avenue, Jinming District, Kaifeng, 475001 PR China
| | - Yousry A. El-Kassaby
- Department of Forest and Conservation Sciences Faculty of Forestry, The University of British Columbia, 2424 Main Mall, Vancouver, BC V6T 1Z4 Canada
| | - Yanming Fang
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Key Laboratory of State Forestry and Grassland Administration On Subtropical Forest Biodiversity Conservation, Nanjing Forestry University, 159 Longpan Road, Nanjing, 210037 PR China
| |
Collapse
|
4
|
Sillo F, Garbelotto M, Giordano L, Gonthier P. Genic introgression from an invasive exotic fungal forest pathogen increases the establishment potential of a sibling native pathogen. NEOBIOTA 2021. [DOI: 10.3897/neobiota.65.64031] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Significant hybridization between the invasive North American fungal plant pathogen Heterobasidion irregulare and its Eurasian sister species H. annosum is ongoing in Italy. Whole genomes of nine natural hybrids were sequenced, assembled and compared with those of three genotypes each of the two parental species. Genetic relationships among hybrids and their level of admixture were determined. A multi-approach pipeline was used to assign introgressed genomic blocks to each of the two species. Alleles that introgressed from H. irregulare to H. annosum were associated with pathways putatively related to saprobic processes, while alleles that introgressed from the native to the invasive species were mainly linked to gene regulation. There was no overlap of allele categories introgressed in the two directions. Phenotypic experiments documented a fitness increase in H. annosum genotypes characterized by introgression of alleles from the invasive species, supporting the hypothesis that hybridization results in putatively adaptive introgression. Conversely, introgression from the native into the exotic species appeared to be driven by selection on genes favoring genome stability. Since the introgression of specific alleles from the exotic H. irregulare into the native H. annosum increased the invasiveness of the latter species, we propose that two invasions may be co-occurring: the first one by genotypes of the exotic species, and the second one by alleles belonging to the exotic species. Given that H. irregulare represents a threat to European forests, monitoring programs need to track not only exotic genotypes in native forest stands, but also exotic alleles introgressed in native genotypes.
Collapse
|
5
|
McFarlane SE, Senn HV, Smith SL, Pemberton JM. Locus-specific introgression in young hybrid swarms: Drift may dominate selection. Mol Ecol 2021; 30:2104-2115. [PMID: 33638185 DOI: 10.1111/mec.15862] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 02/01/2021] [Accepted: 02/17/2021] [Indexed: 12/17/2022]
Abstract
Closely related species that have previously inhabited geographically separated ranges are hybridizing at an increasing rate due to human disruptions. These human-mediated hybrid zones can be used to study reproductive isolation between species at secondary contact, including examining locus-specific rates of introgression. Introgression is expected to be heterogenous across the genome, reflecting variation in selection. Those loci that introgress especially slowly are good candidates for being involved in reproductive isolation, while those loci that introgress quickly may be involved in adaptive introgression. In the context of conservation, policy makers are especially concerned about introduced alleles moving quickly into the background of a native or endemic species, as these alleles could replace the native alleles in the population, leading to extinction via hybridization. We applied genomic cline analyses to 44,997 SNPs to identify loci introgressing more or less when compared to the genome wide expectation in a human-mediated hybridizing population of red deer and sika in Kintyre Scotland. We found 11.4% of SNPs had cline centres that were significantly different from the genome wide expectation, and 17.6% of all SNPs had excess rates of introgression. Based on simulations, we believe that many of these markers have diverged from the genome-wide average due to drift, rather than because of selection, and we suggest that these simulations can be useful as a null distribution for future studies of genomic clines. Future work on red deer and sika could determine the policy implications of allelic-replacement due to drift rather than selection, and could use replicate, geographically distinct hybrid zones to narrow down those loci that are responding to selection.
Collapse
Affiliation(s)
- S Eryn McFarlane
- School of Biological Sciences, Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK.,Department of Biology, Lund University, Lund, Sweden
| | - Helen V Senn
- School of Biological Sciences, Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK.,WildGenes Laboratory, Royal Zoological Society of Scotland, Edinburgh, UK
| | - Stephanie L Smith
- School of Biological Sciences, Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK.,The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Edinburgh, UK
| | - Josephine M Pemberton
- School of Biological Sciences, Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK
| |
Collapse
|
6
|
Popovic I, Bernatchez L. Uncovering endemism in a lake of invasive species introgression. Mol Ecol 2021; 30:880-883. [PMID: 33449362 DOI: 10.1111/mec.15801] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 01/04/2021] [Indexed: 12/24/2022]
Affiliation(s)
- Iva Popovic
- School of Biological Sciences, University of Queensland, St Lucia, Qld, Australia
| | - Louis Bernatchez
- Institut de Biologie Intégrative et des Systémes (IBIS), Université Laval, Québec, QC, Canada
| |
Collapse
|
7
|
Datta A, Kumschick S, Geerts S, Wilson JRU. Identifying safe cultivars of invasive plants: six questions for risk assessment, management, and communication. NEOBIOTA 2020. [DOI: 10.3897/neobiota.62.51635] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The regulation of biological invasions is often focussed at the species level. However, the risks posed by infra- and inter-specific entities can be significantly different from the risks posed by the corresponding species, to the extent that they should be regulated and managed differently. In particular, many ornamental plants have been the subject of long-term breeding and selection programmes, with an increasing focus on trying to develop cultivars and hybrids that are less invasive. In this paper, we frame the problem of determining the risk of invasion posed by cultivars or hybrids as a set of six questions that map on to the key components of a risk analysis, viz., risk identification, risk assessment, risk management, and risk communication. 1) Has an infra- or inter-specific entity been proposed as “safe to use” despite at least one of the corresponding species being a harmful invasive? 2) What are the trait differences between the proposed safe alternative and its corresponding invasive species? 3) Do the differences in traits translate into a difference in invasion risk that is significant for regulation? 4) Are the differences spatially and temporally stable? 5) Can the entities be distinguished from each other in practice? 6) What are the appropriate ways to communicate the risks and what can be done to manage them? For each question, we use examples to illustrate how they might be addressed focussing on plant cultivars that are purported to be safe due to sterility. We review the biological basis of sterility, methods used to generate sterile cultivars, and the methods available to confirm sterility. It is apparent that separating invasive genetic entities from less invasive, but closely related, genetic entities in a manner appropriate for regulation currently remains unfeasible in many circumstances – it is a difficult, expensive and potentially fruitless endeavour. Nonetheless, we strongly believe that an a priori assumption of risk should be inherited from the constituent taxa and the onus (and cost) of proof should be held by those who wish to benefit from infra- (or inter-) specific genetic entities. The six questions outlined here provide a general, science-based approach to distinguish closely-related taxa based on the invasion risks they pose.
Collapse
|
8
|
Genetic Consequences of Hybridization in Relict Isolated Trees Pinus sylvestris and the Pinus mugo Complex. FORESTS 2020. [DOI: 10.3390/f11101086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Scots pine (Pinus sylvestris L.) and the taxa from the P. mugo complex can hybridize in the contact zones and produce fertile hybrids. A unique example of an early Holocene relict population of P. sylvestris and P. uliginosa (a taxon from the P. mugo complex) growing on the tops of Jurassic sandstone rocks is located in Błędne Skały (Sudetes). Phenotypically, there are trees resembling P. sylvestris, P. uliginosa and intermediate forms between them. We expected that some of P. sylvestris and/or P. uliginosa-like trees could be in fact cryptic hybrids resembling one of the parental phenotypes. To address this question, we examined randomly sampled individuals, using a set of plastid (cpDNA), nuclear (nDNA) and mitochondrial (mtDNA) markers as well as biometric characteristics of needles and cones. The results were compared to the same measurements of allopatric reference populations of the P. sylvestris and the P. mugo complex (Pinus mugo s.s, P. uncinata and P. uliginosa). We detected cpDNA barcodes of the P. mugo complex in most individuals with the P. sylvestris phenotype, while we did not detect cpDNA diagnostic of P. sylvestris within P. uliginosa-like trees. These results indicate the presence of cryptic hybrids of the P. sylvestris phenotype. We found only three typical P. sylvestris individuals that were clustered with the species reference populations based on needle and cone characteristics. Most trees showed intermediate characteristics between P. sylvestris and P. uliginosa-like trees, indicating intensive and probably long-lasting hybridization of the taxa at this area and subsequent gene erosion of parental species.
Collapse
|
9
|
Monitoring of the last stronghold of native pool frogs (Pelophylax lessonae) in Western Europe, with implications for their conservation. EUR J WILDLIFE RES 2020. [DOI: 10.1007/s10344-020-01380-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
10
|
Baird HP, Moon KL, Janion‐Scheepers C, Chown SL. Springtail phylogeography highlights biosecurity risks of repeated invasions and intraregional transfers among remote islands. Evol Appl 2020; 13:960-973. [PMID: 32431746 PMCID: PMC7232766 DOI: 10.1111/eva.12913] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 12/08/2019] [Accepted: 12/13/2019] [Indexed: 12/13/2022] Open
Abstract
Human-mediated transport of species outside their natural range is a rapidly growing threat to biodiversity, particularly for island ecosystems that have evolved in isolation. The genetic structure underpinning island populations will largely determine their response to increased transport and thus help to inform biosecurity management. However, this information is severely lacking for some groups, such as the soil fauna. We therefore analysed the phylogeographic structure of an indigenous and an invasive springtail species (Collembola: Poduromorpha), each distributed across multiple remote sub-Antarctic islands, where human activity is currently intensifying. For both species, we generated a genome-wide SNP data set and additionally analysed all available COI barcodes. Genetic differentiation in the indigenous springtail Tullbergia bisetosa is substantial among (and, to a lesser degree, within) islands, reflecting low dispersal and historic population fragmentation, while COI patterns reveal ancestral signatures of postglacial recolonization. This pronounced geographic structure demonstrates the key role of allopatric divergence in shaping the region's diversity and highlights the vulnerability of indigenous populations to genetic homogenization via human transport. For the invasive species Hypogastrura viatica, nuclear genetic structure is much less apparent, particularly for islands linked by regular shipping, while diverged COI haplotypes indicate multiple independent introductions to each island. Thus, human transport has likely facilitated this species' persistence since its initial colonization, through the ongoing introduction and inter-island spread of genetic variation. These findings highlight the different evolutionary consequences of human transport for indigenous and invasive soil species. Crucially, both outcomes demonstrate the need for improved intraregional biosecurity among remote island systems, where the policy focus to date has been on external introductions.
Collapse
Affiliation(s)
- Helena P. Baird
- School of Biological SciencesMonash UniversityClaytonVictoriaAustralia
| | - Katherine L. Moon
- School of Biological SciencesMonash UniversityClaytonVictoriaAustralia
| | - Charlene Janion‐Scheepers
- Iziko Museums of South AfricaCape TownSouth Africa
- Department of Zoology & EntomologyUniversity of the Free StateBloemfonteinSouth Africa
| | - Steven L. Chown
- School of Biological SciencesMonash UniversityClaytonVictoriaAustralia
| |
Collapse
|
11
|
The effect of phylogeographic history on species boundaries: a comparative framework in Hyla tree frogs. Sci Rep 2020; 10:5502. [PMID: 32218506 PMCID: PMC7099067 DOI: 10.1038/s41598-020-62382-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 03/11/2020] [Indexed: 01/13/2023] Open
Abstract
Because it is indicative of reproductive isolation, the amount of genetic introgression across secondary contact zones is increasingly considered in species delimitation. However, patterns of admixture at range margins can be skewed by the regional dynamics of hybrid zones. In this context, we posit an important role for phylogeographic history: hybrid zones located within glacial refugia (putatively formed during the Late-Pleistocene) should be better defined than those located in post-glacial or introduced ranges (putatively formed during the Holocene and the Anthropocene). We test this hypothesis in a speciation continuum of tree frogs from the Western Palearctic (Hyla), featuring ten identified contacts between species spanning Plio-Pleistocene to Miocene divergences. We review the rich phylogeographic literature of this group and examine the overlooked transition between H. arborea and H. molleri in Western France using a multilocus dataset. Our comparative analysis supports a trend that contacts zones resulting from post-glacial expansions and human translocations feature more extensive introgression than those established within refugial areas. Integrating the biogeographic history of incipient species, i.e. their age since first contact together with their genetic divergence, thus appears timely to draw sound evolutionary and taxonomic inferences from patterns of introgression across hybrid zones.
Collapse
|
12
|
McFarlane SE, Hunter DC, Senn HV, Smith SL, Holland R, Huisman J, Pemberton JM. Increased genetic marker density reveals high levels of admixture between red deer and introduced Japanese sika in Kintyre, Scotland. Evol Appl 2020; 13:432-441. [PMID: 31993087 PMCID: PMC6976951 DOI: 10.1111/eva.12880] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 09/01/2019] [Accepted: 10/10/2019] [Indexed: 12/14/2022] Open
Abstract
Hybridization is a natural process at species range boundaries, but increasing numbers of species are hybridizing due to direct or indirect human activities. In such cases of anthropogenic hybridization, subsequent introgression can threaten the survival of native species. To date, many such systems have been studied with too few genetic markers to assess the level of threat resulting from advanced backcrossing. Here, we use 44,999 single nucleotide polymorphisms (SNPs) and the ADMIXTURE program to study two areas of Scotland where a panel of 22 diagnostic microsatellites previously identified introgression between native red deer (Cervus elaphus) and introduced Japanese sika (Cervus nippon). In Kintyre, we reclassify 26% of deer from the pure species categories to the hybrid category whereas in the NW Highlands we only reclassify 2%. As expected, the reclassified individuals are mostly advanced backcrosses. We also investigate the ability of marker panels selected on different posterior allele frequency criteria to find hybrids assigned by the full marker set and show that in our data, ancestry informative markers (i.e. those that are highly differentiated between the species, but not fixed) are better than diagnostic markers (those markers that are fixed between the species) because they are more evenly distributed in the genome. Diagnostic loci are concentrated on the X chromosome to the detriment of autosomal coverage.
Collapse
Affiliation(s)
- S. Eryn McFarlane
- Institute of Evolutionary BiologySchool of Biological ScienceUniversity of EdinburghEdinburghUK
- Department of BiologyLund UniversityLundSweden
| | - Darren C. Hunter
- Institute of Evolutionary BiologySchool of Biological ScienceUniversity of EdinburghEdinburghUK
- Department of Animal and Plant SciencesUniversity of SheffieldSheffieldUK
| | - Helen V. Senn
- Institute of Evolutionary BiologySchool of Biological ScienceUniversity of EdinburghEdinburghUK
- WildGenes LaboratoryRoyal Zoological Society of ScotlandEdinburghUK
| | - Stephanie L. Smith
- Institute of Evolutionary BiologySchool of Biological ScienceUniversity of EdinburghEdinburghUK
- The Royal (Dick) School of Veterinary StudiesUniversity of EdinburghEaster Bush CampusMidlothian, EdinburghUK
| | - Rebecca Holland
- Institute of Evolutionary BiologySchool of Biological ScienceUniversity of EdinburghEdinburghUK
| | - Jisca Huisman
- Institute of Evolutionary BiologySchool of Biological ScienceUniversity of EdinburghEdinburghUK
| | - Josephine M. Pemberton
- Institute of Evolutionary BiologySchool of Biological ScienceUniversity of EdinburghEdinburghUK
| |
Collapse
|
13
|
Chan WY, Hoffmann AA, Oppen MJH. Hybridization as a conservation management tool. Conserv Lett 2019. [DOI: 10.1111/conl.12652] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Wing Yan Chan
- Australian Institute of Marine Science Townsville Queensland Australia
- School of BioSciencesUniversity of Melbourne Melbourne Victoria Australia
| | - Ary A. Hoffmann
- Bio21 InstituteUniversity of Melbourne Melbourne Victoria Australia
| | - Madeleine J. H. Oppen
- Australian Institute of Marine Science Townsville Queensland Australia
- School of BioSciencesUniversity of Melbourne Melbourne Victoria Australia
| |
Collapse
|
14
|
McFarlane SE, Pemberton JM. Detecting the True Extent of Introgression during Anthropogenic Hybridization. Trends Ecol Evol 2019; 34:315-326. [DOI: 10.1016/j.tree.2018.12.013] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 12/10/2018] [Accepted: 12/18/2018] [Indexed: 10/27/2022]
|
15
|
Huebner DC, Bret‐Harte MS. Microsite conditions in retrogressive thaw slumps may facilitate increased seedling recruitment in the Alaskan Low Arctic. Ecol Evol 2019; 9:1880-1897. [PMID: 30847079 PMCID: PMC6392365 DOI: 10.1002/ece3.4882] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 11/22/2018] [Accepted: 12/07/2018] [Indexed: 11/08/2022] Open
Abstract
In Low Arctic tundra, thermal erosion of ice-rich permafrost soils (thermokarst) has increased in frequency since the 1980s. Retrogressive thaw slumps (RTS) are thermokarst disturbances forming large open depressions on hillslopes through soil wasting and vegetation displacement. Tall (>0.5 m) deciduous shrubs have been observed in RTS a decade after disturbance. RTS may provide conditions suitable for seedling recruitment, which may contribute to Arctic shrub expansion. We quantified in situ seedling abundance, and size and viability of soil seedbanks in greenhouse trials for two RTS chronosequences near lakes on Alaska's North Slope. We hypothesized recent RTS provide microsites for greater recruitment than mature RTS or undisturbed tundra. We also hypothesized soil seedbanks demonstrate quantity-quality trade-offs; younger seedbanks contain smaller numbers of mostly viable seed that decrease in viability as seed accumulates over time. We found five times as many seedlings in younger RTS as in older RTS, including birch and willow, and no seedlings in undisturbed tundra. Higher seedling counts were associated with bare soil, warmer soils, higher soil available nitrogen, and less plant cover. Seedbank viability was unrelated to size. Older seedbanks were larger at one chronosequence, with no difference in percent germination. At the other chronosequence, germination was lower from older seedbanks but seedbank size was not different. Seedbank germination was positively associated with in situ seedling abundance at one RTS chronosequence, suggesting postdisturbance revegetation from seedbanks. Thermal erosion may be important for recruitment in tundra by providing bare microsites that are warmer, more nutrient-rich, and less vegetated than in undisturbed ground. Differences between two chronosequences in seedbank size, viability, and species composition suggest disturbance interacts with local conditions to form seedbanks. RTS may act as seedling nurseries to benefit many Arctic species as climate changes, particularly those that do not produce persistent seed.
Collapse
|
16
|
Di Giambattista L, Fulvo A, Fabiani A, Bonanni J, Carrión JE, Gentile G. Molecular data exclude current hybridization between iguanas Conolophus marthae and C. subcristatus on Wolf Volcano (Galápagos Islands). CONSERV GENET 2018. [DOI: 10.1007/s10592-018-1114-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
17
|
Wu ZY, Liu J, Provan J, Wang H, Chen CJ, Cadotte MW, Luo YH, Amorim BS, Li DZ, Milne RI. Testing Darwin's transoceanic dispersal hypothesis for the inland nettle family (Urticaceae). Ecol Lett 2018; 21:1515-1529. [PMID: 30133154 DOI: 10.1111/ele.13132] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 04/11/2018] [Accepted: 07/05/2018] [Indexed: 12/17/2022]
Abstract
Dispersal is a fundamental ecological process, yet demonstrating the occurrence and importance of long-distance dispersal (LDD) remains difficult, having rarely been examined for widespread, non-coastal plants. To address this issue, we integrated phylogenetic, molecular dating, biogeographical, ecological, seed biology and oceanographic data for the inland Urticaceae. We found that Urticaceae originated in Eurasia c. 69 Ma, followed by ≥ 92 LDD events between landmasses. Under experimental conditions, seeds of many Urticaceae floated for > 220 days, and remained viable after 10 months in seawater, long enough for most detected LDD events, according to oceanographic current modelling. Ecological traits analyses indicated that preferences for disturbed habitats might facilitate LDD. Nearly half of all LDD events involved dioecious taxa, so population establishment in dioecious Urticaceae requires multiple seeds, or occasional selfing. Our work shows that seawater LDD played an important role in shaping the geographical distributions of Urticaceae, providing empirical evidence for Darwin's transoceanic dispersal hypothesis.
Collapse
Affiliation(s)
- Zeng-Yuan Wu
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, 650201, China
| | - Jie Liu
- Key Laboratory for Plant and Biodiversity of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, 650201, China
| | - Jim Provan
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, SY23 3DA, UK
| | - Hong Wang
- Key Laboratory for Plant and Biodiversity of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, 650201, China
| | - Chia-Jui Chen
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Marc W Cadotte
- Department of Biological Sciences, University of Toronto-Scarborough, 1265 Military Trail, Toronto, ON, M1C 1A4, Canada.,Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON, M5S 3B2, Canada
| | - Ya-Huang Luo
- Key Laboratory for Plant and Biodiversity of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, 650201, China
| | - Bruno S Amorim
- Graduate Program in Biotechnology and Natural Resources, School of Health Sciences, State University of Amazonas, CEP, 69065-001, Manaus-AM, Brazil
| | - De-Zhu Li
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, 650201, China.,Key Laboratory for Plant and Biodiversity of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, 650201, China
| | - Richard I Milne
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3JH, UK
| |
Collapse
|
18
|
Essl F, Bacher S, Genovesi P, Hulme PE, Jeschke JM, Katsanevakis S, Kowarik I, Kühn I, Pyšek P, Rabitsch W, Schindler S, van Kleunen M, Vilà M, Wilson JRU, Richardson DM. Which Taxa Are Alien? Criteria, Applications, and Uncertainties. Bioscience 2018. [DOI: 10.1093/biosci/biy057] [Citation(s) in RCA: 99] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Franz Essl
- Division of Conservation Biology, Vegetation and Landscape Ecology at the University of Vienna, in Austria; the Department of Biodiversity and Nature Conservation at Environment Agency Austria, in Vienna; and the Centre for Invasion Biology in the Department of Botany and Zoology at Stellenbosch University, in South Africa
| | - Sven Bacher
- Department of Biology at the University of Fribourg, in Switzerland
| | - Piero Genovesi
- Institute for Environmental Protection and Research (ISPRA) and is the chair of the International Union for Conservation of Nature Species Survival Commission Invasive Species Specialist Group, in Rome, Italy
| | - Philip E Hulme
- Bio-Protection Research Centre at Lincoln University, in Christchurch, New Zealand
| | - Jonathan M Jeschke
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB); Freie Universität Berlin; and the Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), in Berlin, Germany
| | - Stelios Katsanevakis
- Department of Marine Sciences at the University of the Aegean, in Mytilene, Greece
| | - Ingo Kowarik
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB) and is chair of ecosystem science/plant ecology at Technische Universität Berlin, in Germany
| | - Ingolf Kühn
- Helmholtz Centre for Environmental Research–UFZ in the Department of Community Ecology, in Halle, Germany; the Geobotany and Botanical Garden at Martin Luther University Halle-Wittenberg, in Halle, Germany; and the German Centre for Integrative Biodiversity Research (iDiv), in Leipzig, Germany
| | - Petr Pyšek
- Institute of Botany and the Department of Invasion Ecology at The Czech Academy of Sciences, in Průhonice, Czech Republic, and with the Department of Ecology at Charles University, in Prague, Czech Republic
| | - Wolfgang Rabitsch
- Department of Biodiversity and Nature Conservation at Environment Agency Austria, in Vienna
| | - Stefan Schindler
- Department of Biodiversity and Nature Conservation at Environment Agency Austria, in Vienna
| | - Mark van Kleunen
- Department of Biology at the University of Konstanz, in Germany, and with the Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation at Taizhou University, in China
| | - Montserrat Vilà
- Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas (EBD-CSIC), in Sevilla, Spain
| | - John R U Wilson
- Centre for Invasion Biology in the Department of Botany and Zoology at Stellenbosch University, in South Africa
- South African National Biodiversity Institute at the Kirstenbosch Research Centre, Cape Town, South Africa
| | - David M Richardson
- Centre for Invasion Biology in the Department of Botany and Zoology at Stellenbosch University, in South Africa
| |
Collapse
|
19
|
Saarman NP, Kober KM, Simison WB, Pogson GH. Sequence-Based Analysis of Thermal Adaptation and Protein Energy Landscapes in an Invasive Blue Mussel (Mytilus galloprovincialis). Genome Biol Evol 2018; 9:2739-2751. [PMID: 28985307 PMCID: PMC5647807 DOI: 10.1093/gbe/evx190] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2017] [Indexed: 12/12/2022] Open
Abstract
Adaptive responses to thermal stress in poikilotherms plays an important role in determining competitive ability and species distributions. Amino acid substitutions that affect protein stability and modify the thermal optima of orthologous proteins may be particularly important in this context. Here, we examine a set of 2,770 protein-coding genes to determine if proteins in a highly invasive heat tolerant blue mussel (Mytilus galloprovincialis) contain signals of adaptive increases in protein stability relative to orthologs in a more cold tolerant M. trossulus. Such thermal adaptations might help to explain, mechanistically, the success with which the invasive marine mussel M. galloprovincialis has displaced native species in contact zones in the eastern (California) and western (Japan) Pacific. We tested for stabilizing amino acid substitutions in warm tolerant M. galloprovincialis relative to cold tolerant M. trossulus with a generalized linear model that compares in silico estimates of recent changes in protein stability among closely related congeners. Fixed substitutions in M. galloprovincialis were 3,180.0 calories per mol per substitution more stabilizing at genes with both elevated dN/dS ratios and transcriptional responses to heat stress, and 705.8 calories per mol per substitution more stabilizing across all 2,770 loci investigated. Amino acid substitutions concentrated in a small number of genes were more stabilizing in M. galloprovincialis compared with cold tolerant M. trossulus. We also tested for, but did not find, enrichment of a priori GO terms in genes with elevated dN/dS ratios in M. galloprovincialis. This might indicate that selection for thermodynamic stability is generic across all lineages, and suggests that the high change in estimated protein stability that we observed in M. galloprovincialis is driven by selection for extra stabilizing substitutions, rather than by higher incidence of selection in a greater number of genes in this lineage. Nonetheless, our finding of more stabilizing amino acid changes in the warm adapted lineage is important because it suggests that adaption for thermal stability has contributed to M. galloprovincialis’ superior tolerance to heat stress, and that pairing tests for positive selection and tests for transcriptional response to heat stress can identify candidates of protein stability adaptation.
Collapse
Affiliation(s)
- Norah P Saarman
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz.,Department of Ecology and Evolutionary Biology, Yale University
| | - Kord M Kober
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz.,Department of Physiological Nursing, University of California, San Francisco.,Institute for Computational Health Sciences, University of California, San Francisco
| | - W Brian Simison
- Center for Comparative Genomics, California Academy of Sciences, San Francisco, California
| | - Grant H Pogson
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz
| |
Collapse
|
20
|
Wielstra B, Burke T, Butlin RK, Schaap O, Shaffer HB, Vrieling K, Arntzen JW. Efficient screening for ‘genetic pollution’ in an anthropogenic crested newt hybrid zone. CONSERV GENET RESOUR 2016. [DOI: 10.1007/s12686-016-0582-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
21
|
McTaggart AR, van der Nest MA, Steenkamp ET, Roux J, Slippers B, Shuey LS, Wingfield MJ, Drenth A. Fungal Genomics Challenges the Dogma of Name-Based Biosecurity. PLoS Pathog 2016; 12:e1005475. [PMID: 27149511 PMCID: PMC4858198 DOI: 10.1371/journal.ppat.1005475] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Alistair R. McTaggart
- Department of Microbiology and Plant Pathology, Tree Protection Co-operative Programme (TPCP), Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, Gauteng, South Africa
- * E-mail:
| | - Magriet A. van der Nest
- Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, Gauteng, South Africa
| | - Emma T. Steenkamp
- Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, Gauteng, South Africa
| | - Jolanda Roux
- Department of Plant Sciences, Tree Protection Co-operative Programme (TPCP), Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, Gauteng, South Africa
| | - Bernard Slippers
- Department of Microbiology and Plant Pathology, Tree Protection Co-operative Programme (TPCP), Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, Gauteng, South Africa
| | - Louise S. Shuey
- Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, Gauteng, South Africa
| | - Michael J. Wingfield
- Department of Microbiology and Plant Pathology, Tree Protection Co-operative Programme (TPCP), Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, Gauteng, South Africa
| | - André Drenth
- Queensland Alliance for Agriculture and Food Innovation (QAAFI), University of Queensland, Brisbane, Queensland, Australia
| |
Collapse
|
22
|
Moody ML, Palomino N, Weyl PSR, Coetzee JA, Newman RM, Harms NE, Liu X, Thum RA. Unraveling the biogeographic origins of the Eurasian watermilfoil (Myriophyllum spicatum) invasion in North America. AMERICAN JOURNAL OF BOTANY 2016; 103:709-718. [PMID: 27033316 DOI: 10.3732/ajb.1500476] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 02/17/2016] [Indexed: 06/05/2023]
Abstract
PREMISE OF THE STUDY Using phylogeographic analyses to determine the geographic origins of biological invaders is important for identifying environmental adaptations and genetic composition in their native range as well as biocontrol agents among indigenous herbivores. Eurasian watermilfoil (Myriophyllum spicatum) and its hybrid with northern watermilfoil (M. sibiricum) are found throughout the contiguous United States and southern Canada, forming one of the most economically costly aquatic plant invasions in North America, yet the geographic origin of the invasion remains unknown. The objectives of our study included determining the geographic origin of Eurasian watermilfoil in North America as well as the maternal lineage of the hybrids. METHODS DNA sequence data from a cpDNA intron and the nrDNA ITS region were compiled for accessions from 110 populations of Eurasian watermilfoil and hybrids from North America and the native range (including Europe, Asia, and Africa). Datasets were analyzed using statistical parsimony and Bayesian phylogenetics to assess the geographic origin of the invasion. KEY RESULTS The two Eurasian watermilfoil cpDNA haplotypes in North America are also found from China and Korea, but not elsewhere in the native range. These haplotypes did not overlap and were limited in native geographic range. The ovule parent for hybrids can come from either parental lineage, and multiple haplotypes from both parental species were found. CONCLUSIONS The geographic origin of this prolific aquatic plant invasion of North America is in Asia. This provides critical information to better understand the invasion pathway and inform management into the future.
Collapse
Affiliation(s)
- Michael L Moody
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas, USA
| | - Nayell Palomino
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas, USA
| | - Philip S R Weyl
- Department of Zoology and Entomology, Rhodes University, Grahamstown, 6140, South Africa
| | - Julie A Coetzee
- Department of Zoology and Entomology, Rhodes University, Grahamstown, 6140, South Africa
| | - Raymond M Newman
- Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota, St. Paul, Minnesota, USA
| | - Nathan E Harms
- U.S. Army Engineer Research and Development Center, Environmental Laboratory, 3909 Halls Ferry Rd., Vicksburg, Mississippi, USA
| | - Xing Liu
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan, Hubei, China
| | - Ryan A Thum
- Department of Plant Sciences & Plant Pathology, Montana State University, Bozeman, Montana, USA
| |
Collapse
|
23
|
Crooks JA. Lag times and exotic species: The ecology and management of biological invasions in slow-motion1. ECOSCIENCE 2016. [DOI: 10.2980/i1195-6860-12-3-316.1] [Citation(s) in RCA: 471] [Impact Index Per Article: 58.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
24
|
Hamilton JA, Miller JM. Adaptive introgression as a resource for management and genetic conservation in a changing climate. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2016; 30:33-41. [PMID: 26096581 DOI: 10.1111/cobi.12574] [Citation(s) in RCA: 179] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 06/15/2015] [Accepted: 06/17/2015] [Indexed: 05/22/2023]
Abstract
Current rates of climate change require organisms to respond through migration, phenotypic plasticity, or genetic changes via adaptation. We focused on questions regarding species' and populations' ability to respond to climate change through adaptation. Specifically, the role adaptive introgression, movement of genetic material from the genome of 1 species into the genome of another through repeated interbreeding, may play in increasing species' ability to respond to a changing climate. Such interspecific gene flow may mediate extinction risk or consequences of limited adaptive potential that result from standing genetic variation and mutation alone, enabling a quicker demographic recovery in response to changing environments. Despite the near dismissal of the potential benefits of hybridization by conservation practitioners, we examined a number of case studies across different taxa that suggest gene flow between sympatric or parapatric sister species or within species that exhibit strong ecotypic differentiation may represent an underutilized management option to conserve evolutionary potential in a changing environment. This will be particularly true where advanced-generation hybrids exhibit adaptive traits outside the parental phenotypic range, a phenomenon known as transgressive segregation. The ideas presented in this essay are meant to provoke discussion regarding how we maintain evolutionary potential, the conservation value of natural hybrid zones, and consideration of their important role in adaptation to climate.
Collapse
Affiliation(s)
- Jill A Hamilton
- Department of Evolution and Ecology, University of California, Davis, CA, 95616, U.S.A..
- Department of Biological Sciences, North Dakota State University, Fargo, ND, 58102, U.S.A..
| | - Joshua M Miller
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, T6G 2E9, Canada
| |
Collapse
|
25
|
Saarman NP, Pogson GH. Introgression between invasive and native blue mussels (genusMytilus) in the central California hybrid zone. Mol Ecol 2015; 24:4723-38. [DOI: 10.1111/mec.13340] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 07/28/2015] [Accepted: 07/29/2015] [Indexed: 01/05/2023]
Affiliation(s)
- Norah P. Saarman
- Department of Ecology and Evolutionary Biology; Yale University; PO Box 208106 New Haven CT 06520-8106 USA
| | - Grant H. Pogson
- Department of Ecology and Evolutionary Biology; UC Santa Cruz; Santa Cruz CA 95064 USA
| |
Collapse
|
26
|
Wilmshurst JM, McGlone MS, Turney CSM. Long-term ecology resolves the timing, region of origin and process of establishment for a disputed alien tree. AOB PLANTS 2015; 7:plv104. [PMID: 26311733 PMCID: PMC4612295 DOI: 10.1093/aobpla/plv104] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Accepted: 07/22/2015] [Indexed: 05/28/2023]
Abstract
Alien plants are a pervasive environmental problem, particularly on islands where they can rapidly transform unique indigenous ecosystems. However, often it is difficult to confidently determine whether a species is native or alien, especially if establishment occurred before historical records. This can present a management challenge: for example, should such taxa be eradicated or left alone until their region of origin and status are clarified? Here we show how combining palaeoecological and historical records can help resolve such dilemmas, using the tree daisy Olearia lyallii on the remote New Zealand subantarctic Auckland Islands as a case study. The status of this tree as native or introduced has remained uncertain for the 175 years since it was first discovered on the Auckland Islands, and its appropriate management is debated. Elsewhere, O. lyallii has a highly restricted distribution on small sea bird-rich islands within a 2° latitudinal band south of mainland New Zealand. Analysis of palaeoecological and historical records from the Auckland Islands suggest that O. lyallii established there c. 1807 when these islands were first exploited by European sealers. Establishment was facilitated by anthropogenic burning and clearing and its subsequent spread has been slow, limited in distribution and probably human-assisted. Olearia lyallii has succeeded mostly in highly disturbed sites which are also nutrient enriched from nesting sea birds, seals and sea spray. This marine subsidy has fuelled the rapid growth of O. lyallii and allowed this tree to be competitive against the maritime communities it has replaced. Although endemic to the New Zealand region, our evidence suggests that O. lyallii is alien to the Auckland Islands. Although such 'native' aliens can pose unique management challenges on islands, in this instance we suggest that ongoing monitoring with no control is an appropriate management action, as O. lyallii appears to pose minimal risk to ecological integrity.
Collapse
Affiliation(s)
- Janet M Wilmshurst
- Landcare Research, PO Box 69040, Lincoln 7640, New Zealand School of Environment, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Matt S McGlone
- Landcare Research, PO Box 69040, Lincoln 7640, New Zealand
| | - Chris S M Turney
- School of Biological, Earth and Environmental Sciences, University of New South Wales, NSW 2052, Australia
| |
Collapse
|
27
|
Ramírez-Valiente JA, Robledo-Arnuncio JJ. Adaptive consequences of human-mediated introgression for indigenous tree species: the case of a relict Pinus pinaster population. TREE PHYSIOLOGY 2014; 34:1376-1387. [PMID: 25466514 DOI: 10.1093/treephys/tpu097] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Human-induced gene movement via afforestation and restoration programs is a widespread phenomenon throughout the world. However, its effects on the genetic composition of native populations have received relatively little attention, particularly in forest trees. Here, we examine to what extent gene flow from allochthonous plantations of Pinus pinaster Aiton impacts offspring performance in a neighboring relict natural population and discuss the potential consequences for the long-term genetic composition of the latter. Specifically, we conducted a greenhouse experiment involving two contrasting watering treatments to test for differences in a set of functional traits and mortality rates between P. pinaster progenies from three different parental origins: (i) local native parents, (ii) exotic parents and (iii) intercrosses between local mothers and exotic fathers (intraspecific hybrids). Our results showed differences among crosses in cumulative mortality over time: seedlings of exotic parents exhibited the lowest mortality rates and seedlings of local origin the highest, while intraspecific hybrids exhibited an intermediate response. Linear regressions showed that seedlings with higher water-use efficiency (WUE, δ(13)C) were more likely to survive under drought stress, consistent with previous findings suggesting that WUE has an important role under dry conditions in this species. However, differences in mortality among crosses were only partially explained by WUE. Other non-measured traits and factors such as inbreeding depression in the relict population are more likely to explain the lower performance of native progenies. Overall, our results indicated that intraspecific hybrids and exotic individuals are more likely to survive under stressful conditions than local native individuals, at least during the first year of development. Since summer drought is the most important demographic and selective filter affecting tree establishment in Mediterranean ecosystems, a potential early selective advantage of exotic and hybrid genotypes would enhance initial steps of introgression of non-native genes into the study relict population of P. pinaster.
Collapse
Affiliation(s)
- José Alberto Ramírez-Valiente
- Department of Forest Ecology and Genetics, INIA-CIFOR, Carretera de La Coruña km 7.5, E-28040 Madrid, Spain Present address: Department of Ecology, Evolution and Behavior, University of Minnesota, 1987 Upper Buford Circle, Saint Paul, MN 55108, USA
| | - Juan José Robledo-Arnuncio
- Department of Forest Ecology and Genetics, INIA-CIFOR, Carretera de La Coruña km 7.5, E-28040 Madrid, Spain
| |
Collapse
|
28
|
Rieux A, Soubeyrand S, Bonnot F, Klein EK, Ngando JE, Mehl A, Ravigne V, Carlier J, de Lapeyre de Bellaire L. Long-distance wind-dispersal of spores in a fungal plant pathogen: estimation of anisotropic dispersal kernels from an extensive field experiment. PLoS One 2014; 9:e103225. [PMID: 25116080 PMCID: PMC4130500 DOI: 10.1371/journal.pone.0103225] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 06/30/2014] [Indexed: 11/19/2022] Open
Abstract
Given its biological significance, determining the dispersal kernel (i.e., the distribution of dispersal distances) of spore-producing pathogens is essential. Here, we report two field experiments designed to measure disease gradients caused by sexually- and asexually-produced spores of the wind-dispersed banana plant fungus Mycosphaerella fijiensis. Gradients were measured during a single generation and over 272 traps installed up to 1000 m along eight directions radiating from a traceable source of inoculum composed of fungicide-resistant strains. We adjusted several kernels differing in the shape of their tail and tested for two types of anisotropy. Contrasting dispersal kernels were observed between the two types of spores. For sexual spores (ascospores), we characterized both a steep gradient in the first few metres in all directions and rare long-distance dispersal (LDD) events up to 1000 m from the source in two directions. A heavy-tailed kernel best fitted the disease gradient. Although ascospores distributed evenly in all directions, average dispersal distance was greater in two different directions without obvious correlation with wind patterns. For asexual spores (conidia), few dispersal events occurred outside of the source plot. A gradient up to 12.5 m from the source was observed in one direction only. Accordingly, a thin-tailed kernel best fitted the disease gradient, and anisotropy in both density and distance was correlated with averaged daily wind gust. We discuss the validity of our results as well as their implications in terms of disease diffusion and management strategy.
Collapse
Affiliation(s)
| | - Samuel Soubeyrand
- INRA, UR546 Biostatistics and Spatial Processes (BioSP), Avignon, France
| | | | - Etienne K. Klein
- INRA, UR546 Biostatistics and Spatial Processes (BioSP), Avignon, France
| | - Josue E. Ngando
- Centre Africain de Recherches sur Bananiers et Plantains (CARBAP) – Njombe, Cameroon
| | | | | | | | | |
Collapse
|
29
|
Roe AD, MacQuarrie CJK, Gros-Louis MC, Simpson JD, Lamarche J, Beardmore T, Thompson SL, Tanguay P, Isabel N. Fitness dynamics within a poplar hybrid zone: II. Impact of exotic sex on native poplars in an urban jungle. Ecol Evol 2014; 4:1876-89. [PMID: 24963382 PMCID: PMC4063481 DOI: 10.1002/ece3.1028] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 12/20/2013] [Accepted: 12/31/2013] [Indexed: 01/11/2023] Open
Abstract
Trees bearing novel or exotic gene components are poised to contribute to the bioeconomy for a variety of purposes such as bioenergy production, phytoremediation, and carbon sequestration within the forestry sector, but sustainable release of trees with novel traits in large-scale plantations requires the quantification of risks posed to native tree populations. Over the last century, exotic hybrid poplars produced through artificial crosses were planted throughout eastern Canada as ornamentals or windbreaks and these exotics provide a proxy by which to examine the fitness of exotic poplar traits within the natural environment to assess risk of exotic gene escape, establishment, and spread into native gene pools. We assessed postzygotic fitness traits of native and exotic poplars within a naturally regenerated stand in eastern Canada (Quebec City, QC). Pure natives (P. balsamifera and P. deltoides spp. deltoides), native hybrids (P. deltoides × P. balsamifera), and exotic hybrids (trees bearing Populus nigra and P. maximowiczii genetic components) were screened for reproductive biomass, yield, seed germination, and fungal disease susceptibility. Exotic hybrids expressed fitness traits intermediate to pure species and were not significantly different from native hybrids. They formed fully viable seed and backcrossed predominantly with P. balsamifera. These data show that exotic hybrids were not unfit and were capable of establishing and competing within the native stand. Future research will seek to examine the impact of exotic gene regions on associated biotic communities to fully quantify the risk exotic poplars pose to native poplar forests.
Collapse
Affiliation(s)
- Amanda D Roe
- Natural Resources Canada, Canadian Forest ServiceQuébec, Québec, Canada
- Natural Resources Canada, Canadian Forest ServiceSault Ste. Marie, Ontario, Canada
| | - Chris JK MacQuarrie
- Natural Resources Canada, Canadian Forest ServiceSault Ste. Marie, Ontario, Canada
| | | | - J Dale Simpson
- Natural Resources Canada, Canadian Forest ServiceFredericton, New-Brunswick, Canada
| | - Josyanne Lamarche
- Natural Resources Canada, Canadian Forest ServiceSault Ste. Marie, Ontario, Canada
| | - Tannis Beardmore
- Natural Resources Canada, Canadian Forest ServiceFredericton, New-Brunswick, Canada
| | - Stacey L Thompson
- Natural Resources Canada, Canadian Forest ServiceQuébec, Québec, Canada
- Umeå University, Department of Ecology and Environmental Science, Umeå Plant Science CentreUmeå, Sweden
| | - Philippe Tanguay
- Natural Resources Canada, Canadian Forest ServiceQuébec, Québec, Canada
| | - Nathalie Isabel
- Natural Resources Canada, Canadian Forest ServiceQuébec, Québec, Canada
| |
Collapse
|
30
|
Zenni RD, Bailey JK, Simberloff D. Rapid evolution and range expansion of an invasive plant are driven by provenance-environment interactions. Ecol Lett 2014; 17:727-35. [DOI: 10.1111/ele.12278] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 03/13/2014] [Accepted: 03/17/2014] [Indexed: 01/11/2023]
Affiliation(s)
- Rafael D. Zenni
- Department of Ecology & Evolutionary Biology; The University of Tennessee; 569 Dabney Hall Knoxville TN 37996 USA
| | - Joseph K. Bailey
- Department of Ecology & Evolutionary Biology; The University of Tennessee; 569 Dabney Hall Knoxville TN 37996 USA
| | - Daniel Simberloff
- Department of Ecology & Evolutionary Biology; The University of Tennessee; 569 Dabney Hall Knoxville TN 37996 USA
| |
Collapse
|
31
|
Wilson JRU, Caplat P, Dickie IA, Hui C, Maxwell BD, Nuñez MA, Pauchard A, Rejmánek M, Richardson DM, Robertson MP, Spear D, Webber BL, van Wilgen BW, Zenni RD. A standardized set of metrics to assess and monitor tree invasions. Biol Invasions 2013. [DOI: 10.1007/s10530-013-0605-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
32
|
Schmiedel D, Huth F, Wagner S. Using data from seed-dispersal modelling to manage invasive tree species: the example of Fraxinus pennsylvanica Marshall in Europe. ENVIRONMENTAL MANAGEMENT 2013; 52:851-60. [PMID: 23974901 DOI: 10.1007/s00267-013-0135-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 07/19/2013] [Indexed: 05/15/2023]
Abstract
Management strategies to control invasive species need information about dispersal distances to predict establishment potential. Fraxinus pennsylvanica is a North American anemochorous tree species that is invasive in many Central European floodplain forests. To predict seed-dispersal potential, the stochastic model WaldStat was used, which enables different options for directionality (isotropic and anisotropic) to be simulated. In this article, we (1) show empirical results of fructification and seed dispersal for this tree species. The model predicts approximately 250,000 seeds for one F. pennsylvanica tree. These results were used to (2) calculate species-specific dispersal distances and effects of wind direction. To consider the influence of wind on dispersal potential of the tree species, long-distance dispersal (LDD [95th percentile dispersal distance]) was calculated. Mean dispersal distances varied between 47 and 66 m. LDD values modelled along the main wind direction ranged from 60 to 150 m. Seed production, dispersal distance, and direction data were (3) incorporated into theoretical management scenarios for forest ecosystems. Finally (4), we discuss management options and the practical relevance of model scenarios in relation to the accuracy of spatial dispersal predictions. Further analyses should be focused on possible, well-adapted management concepts at stand level that could restrict the potential spread of invasive species.
Collapse
Affiliation(s)
- Doreen Schmiedel
- Technische Universität Dresden-Institute for General Ecology and Environmental Protection, Pienner Straße 7, 01737, Tharandt, Germany,
| | | | | |
Collapse
|
33
|
Pyšek P, Hulme PE, Meyerson LA, Smith GF, Boatwright JS, Crouch NR, Figueiredo E, Foxcroft LC, Jarošík V, Richardson DM, Suda J, Wilson JRU. Hitting the right target: taxonomic challenges for, and of, plant invasions. AOB PLANTS 2013; 5:plt042. [PMCID: PMC4455668 DOI: 10.1093/aobpla/plt042] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 09/10/2013] [Indexed: 05/25/2023]
Abstract
Taxonomic resources are essential for the effective management of invasive plants because biosecurity strategies, legislation dealing with invasive species, quarantine, weed surveillance and monitoring all depend on accurate and rapid identification of non-native taxa, and incorrect identifications can impede ecological studies. On the other hand, biological invasions have provided important tests of basic theories about species concepts. Modern taxonomy therefore needs to integrate both classical and new concepts and approaches to improve the accuracy of species identification and further refine taxonomic classification at the level of populations and genotypes in the field and laboratory. This paper explores how a lack of taxonomic expertise, and by implication a dearth of taxonomic products such as identification tools, has hindered progress in understanding and managing biological invasions. It also explores how the taxonomic endeavour could benefit from studies of invasive species. We review the literature on the current situation in taxonomy with a focus on the challenges of identifying alien plant species and explore how this has affected the study of biological invasions. Biosecurity strategies, legislation dealing with invasive species, quarantine, weed surveillance and monitoring all depend on accurate and rapid identification of non-native taxa. However, such identification can be challenging because the taxonomic skill base in most countries is diffuse and lacks critical mass. Taxonomic resources are essential for the effective management of invasive plants and incorrect identifications can impede ecological studies. On the other hand, biological invasions have provided important tests of basic theories about species concepts. Better integration of classical alpha taxonomy and modern genetic taxonomic approaches will improve the accuracy of species identification and further refine taxonomic classification at the level of populations and genotypes in the field and laboratory. Modern taxonomy therefore needs to integrate both classical and new concepts and approaches. In particular, differing points of view between the proponents of morphological and molecular approaches should be negotiated because a narrow taxonomic perspective is harmful; the rigour of taxonomic decision-making clearly increases if insights from a variety of different complementary disciplines are combined and confronted. Taxonomy plays a critical role in the study of plant invasions and in turn benefits from the insights gained from these studies.
Collapse
Affiliation(s)
- Petr Pyšek
- Institute of Botany, Department of Invasion Ecology, Academy of Sciences of the Czech Republic, CZ-252 43 Průhonice, Czech Republic
- Department of Ecology, Faculty of Science, Charles University in Prague, Viničná 7, CZ-128 44 Prague, Czech Republic
| | - Philip E. Hulme
- The Bio-Protection Research Centre, Lincoln University, PO Box 84, Canterbury, New Zealand
| | - Laura A. Meyerson
- Department of Natural Resources Science, University of Rhode Island, 1 Greenhouse Road, Kingston, RI 02881, USA
| | - Gideon F. Smith
- South African National Biodiversity Institute, Biosystematics Research and Biodiversity Collections Division, Private Bag X101, Pretoria 0001, South Africa
- H. G. W. J. Schweickerdt Herbarium, Department of Plant Science, University of Pretoria, Pretoria 0002, South Africa
- Centre for Functional Ecology, Departamento de Ciências da Vida, Universidade de Coimbra, 3001-455 Coimbra, Portugal
| | - James S. Boatwright
- Department of Biodiversity and Conservation Biology, University of the Western Cape, Private Bag X17, Belville 7535, Cape Town, South Africa
| | - Neil R. Crouch
- Ethnobotany Unit, South African National Biodiversity Institute, PO Box 52099, 4007 Berea Road, Durban, South Africa
- School of Chemistry, University of KwaZulu-Natal, Durban 4041, South Africa
| | - Estrela Figueiredo
- Centre for Functional Ecology, Departamento de Ciências da Vida, Universidade de Coimbra, 3001-455 Coimbra, Portugal
- Department of Botany, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031, South Africa
| | - Llewellyn C. Foxcroft
- Conservation Services, South African National Parks, Skukuza 1350, South Africa
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland 7602, South Africa
| | - Vojtěch Jarošík
- Institute of Botany, Department of Invasion Ecology, Academy of Sciences of the Czech Republic, CZ-252 43 Průhonice, Czech Republic
- Department of Ecology, Faculty of Science, Charles University in Prague, Viničná 7, CZ-128 44 Prague, Czech Republic
| | - David M. Richardson
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland 7602, South Africa
| | - Jan Suda
- Department of Botany, Faculty of Science, Charles University in Prague, Benátská 2, CZ-128 01 Prague, Czech Republic
- Institute of Botany, Laboratory of Flow Cytometry, Academy of Sciences of the Czech Republic, CZ-252 43 Průhonice, Czech Republic
| | - John R. U. Wilson
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland 7602, South Africa
- South African National Biodiversity Institute, Kirstenbosch Research Centre, Invasive Species Programme, Claremont 7735, South Africa
| |
Collapse
|
34
|
Gaskin JF, Schwarzländer M, Kinter CL, Smith JF, Novak SJ. Propagule pressure, genetic structure, and geographic origins of Chondrilla juncea (Asteraceae): an apomictic invader on three continents. AMERICAN JOURNAL OF BOTANY 2013; 100:1871-82. [PMID: 24018855 DOI: 10.3732/ajb.1200621] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
PREMISE OF THE STUDY Assessing propagule pressure and geographic origins of invasive species provides insight into the invasion process. Rush skeletonweed (Chondrilla juncea; Asteraceae) is an apomictic, perennial plant that is invasive in Australia, South America (Argentina), and North America (Canada and the United States). This study comprehensively compares propagule pressure and geographic structure of genotypes to improve our understanding of a clonal invasion and enhance management strategies. • METHODS We analyzed 1056 native range plants from Eurasia and 1156 plants from three invaded continents using amplified fragment length polymorphism (AFLP) techniques. We used measures of diversity (Simpson's D) and evenness (E), analysis of molecular variance, and Mantel tests to compare invasions, and genotype similarity to determine origins of invasive genotypes. • KEY RESULTS We found 682 unique genotypes in the native range, but only 13 in the invaded regions. Each invaded region contained distinct AFLP genotypes, suggesting independent introduction events, probably with different geographic origins. Relatively low propagule pressure was associated with each introduction around the globe, but levels of among-population variation differed. We found exact AFLP genotype matches between the native and invaded ranges for five of the 13 invasive genotypes. • CONCLUSIONS Invasion dynamics can vary across invaded ranges within a species. Intensive sampling for molecular analyses can provide insight for understanding intraspecific invasion dynamics, which can hold significance for the management of plant species, especially by finding origins and distributions of invasive genotypes for classical biological control efforts.
Collapse
Affiliation(s)
- John F Gaskin
- USDA Agricultural Research Service, Northern Plains Agricultural Research Laboratory, 1500 N. Central Ave., Sidney, Montana 59270, USA
| | | | | | | | | |
Collapse
|
35
|
Genetic exchange between two freshwater apple snails, Pomacea canaliculata and Pomacea maculata invading East and Southeast Asia. Biol Invasions 2013. [DOI: 10.1007/s10530-013-0431-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
36
|
JAY FLORA, MANEL STÉPHANIE, ALVAREZ NADIR, DURAND ERICY, THUILLER WILFRIED, HOLDEREGGER ROLF, TABERLET PIERRE, FRANÇOIS OLIVIER. Forecasting changes in population genetic structure of alpine plants in response to global warming. Mol Ecol 2012; 21:2354-68. [DOI: 10.1111/j.1365-294x.2012.05541.x] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
37
|
VALTUEÑA FRANCISCOJ, PRESTON CHRISD, KADEREIT JOACHIMW. Evolutionary significance of the invasion of introduced populations into the native range of Meconopsis cambrica. Mol Ecol 2011; 20:4318-31. [DOI: 10.1111/j.1365-294x.2011.05273.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
38
|
Coghlan ML, White NE, Parkinson L, Haile J, Spencer PBS, Bunce M. Egg forensics: an appraisal of DNA sequencing to assist in species identification of illegally smuggled eggs. Forensic Sci Int Genet 2011; 6:268-73. [PMID: 21741338 PMCID: PMC7102845 DOI: 10.1016/j.fsigen.2011.06.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 05/12/2011] [Accepted: 06/13/2011] [Indexed: 10/29/2022]
Abstract
Psittaciformes (parrots and cockatoos) are charismatic birds, their plumage and capacity for learning make them highly sought after pets. The illegal trade in parrots and cockatoos poses a serious threat to the viability of native populations; in addition, species transported to non-endemic areas may potentially vector disease and genetically 'pollute' local native avifauna. To reduce the logistical difficulties associated with trafficking live birds, smugglers often transport eggs. This creates a problem for authorities in elucidating accurate species identification without the laborious task of incubation and hand rearing until a morphological identification can be made. Here, we use 99 avian eggs seized from carriers coming into and within Australia, as a result of suspected illegal trade. We investigate and evaluate the use of mitochondrial DNA (mtDNA) to accurately identify eggs to family, genus or species level. However, Identification of a species based on percentage mtDNA similarities is difficult without good representations of the inter- and intra-levels of species variation. Based on the available reference database, we were able to identify 52% of the eggs to species level. Of those, 10 species from eight genera were detected, all of which belong to the parrot (Psittacidae) and cockatoo (Cacatuidae) families. Of the remaining 48%, a further 36% of eggs were identified to genus level, and 12% identified to family level using our assignment criteria. Clearly the lack of validated DNA reference sequences is hindering our ability to accurately assign a species identity, and accordingly, we advocate that more attention needs to be paid to establishing validated, multi locus mtDNA reference databases for exotic birds that can both assist in genetic identifications and withstand legal scrutiny.
Collapse
Affiliation(s)
- Megan L Coghlan
- Australian Wildlife Forensic Services and Ancient DNA Laboratory, School of Biological Sciences and Biotechnology, Murdoch University, South St, Murdoch, WA 6150, Australia
| | | | | | | | | | | |
Collapse
|
39
|
Jürgens AH, Seitz B, Kowarik I. Genetic differentiation of three endangered wild roses in northeastern Germany: Rosa inodora Fries, Rosa sherardii Davies and Rosa subcollina (H. Christ) Keller. PLANT BIOLOGY (STUTTGART, GERMANY) 2011; 13:524-33. [PMID: 21489104 DOI: 10.1111/j.1438-8677.2010.00406.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Because of increased interest in the use of local provenances for restoration or landscaping projects, information about the genetic differentiation of plant species is required to delineate provenances for seed collection. To obtain information about population distinctiveness of endangered Rosa species occurring in Brandenburg (northeast Germany), we investigated the genetic differentiation of Rosa inodora, R. sherardii and R. subcollina using RAPD markers. All three species were uncommon in our study region. Φ-statistics, estimated by amova, revealed a low interpopulation differentiation for R. inodora (Φ(PT) = 0.19, P < 0.0001) and higher values for R. sherardii and R. subcollina (Φ(PT) = 0.29 and 0.30, P < 0.0001). UPGMA dendrograms and NMDS showed clear spatial differentiation for all species and a correlation between geographic and genetic distances. Due to predominantly high values of genetic differentiation and spatial patterns of ordination, we suggest small provenance regions for endangered Rosa species for seed collection.
Collapse
Affiliation(s)
- A H Jürgens
- Department of Ecology, Technische Universität Berlin, Berlin, Germany
| | | | | |
Collapse
|
40
|
Crispo E, Moore JS, Lee-Yaw JA, Gray SM, Haller BC. Broken barriers: human-induced changes to gene flow and introgression in animals: an examination of the ways in which humans increase genetic exchange among populations and species and the consequences for biodiversity. Bioessays 2011; 33:508-18. [PMID: 21523794 DOI: 10.1002/bies.201000154] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We identify two processes by which humans increase genetic exchange among groups of individuals: by affecting the distribution of groups and dispersal patterns across a landscape, and by affecting interbreeding among sympatric or parapatric groups. Each of these processes might then have two different effects on biodiversity: changes in the number of taxa through merging or splitting of groups, and the extinction/extirpation of taxa through effects on fitness. We review the various ways in which humans are affecting genetic exchange, and highlight the difficulties in predicting the impacts on biodiversity. Gene flow and hybridization are crucially important evolutionary forces influencing biodiversity. Humans alter natural patterns of genetic exchange in myriad ways, and these anthropogenic effects are likely to influence the genetic integrity of populations and species. We argue that taking a gene-centric view towards conservation will help resolve issues pertaining to conservation and management. Editor's suggested further reading in BioEssays A systemic view of biodiversity and its conservation: Processes, interrelationships, and human culture Abstract.
Collapse
Affiliation(s)
- Erika Crispo
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada.
| | | | | | | | | |
Collapse
|
41
|
Affiliation(s)
- Howard M Huynh
- Department of Biology, Acadia University, Wolfville, Nova Scotia, Canada.
| |
Collapse
|
42
|
BRYJA J, SMITH C, KONEČNÝ A, REICHARD M. Range‐wide population genetic structure of the European bitterling (
Rhodeus amarus
) based on microsatellite and mitochondrial DNA analysis. Mol Ecol 2010; 19:4708-22. [DOI: 10.1111/j.1365-294x.2010.04844.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- J. BRYJA
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, 603 65 Brno, Czech Republic
| | - C. SMITH
- School of Biology, University of St Andrews, St Andrews, Fife KY16 8LB, UK
| | - A. KONEČNÝ
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, 603 65 Brno, Czech Republic
| | - M. REICHARD
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, 603 65 Brno, Czech Republic
- School of Biology, University of St Andrews, St Andrews, Fife KY16 8LB, UK
| |
Collapse
|
43
|
Salvini D, Bruschi P, Fineschi S, Grossoni P, Kjaer ED, Vendramin GG. Natural hybridisation between Quercus petraea (Matt.) Liebl. and Quercus pubescens Willd. within an Italian stand as revealed by microsatellite fingerprinting. PLANT BIOLOGY (STUTTGART, GERMANY) 2009; 11:758-765. [PMID: 19689784 DOI: 10.1111/j.1438-8677.2008.00158.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Interspecific gene flow is frequently reported in the genus Quercus. However, interfertile oak species often seem to remain distinct, even within areas of sympatry. This study employed molecular markers to verify, at a fine scale, the presence of interspecific gene flow in a natural population of Quercus petraea and Quercus pubescens. Within a delimited area of 6 ha, all adult trees belonging to the studied oak complex and seeds from a subsample of such trees were collected and analysed using molecular microsatellite markers. A low interspecific genetic differentiation and a high level of interspecific genetic admixture suggested past hybridisation. Paternity inference of seeds allowed the estimation of pollination frequencies from the three groups of pollen donors (Q. petraea, Q. pubescens, intermediate). We also assayed pollen viability and germinability of each species group. We observed natural hybridisation between Q. petraea and Q. pubescens, with a predominant component in the direction Q. petraea --> Q. pubescens: Q. pubescens displayed a higher level of heterospecific pollination by Q. petraea (25.8%) and intermediate morphotypes (14.7%), compared to Q. petraea acting as pollen receptor (with less than 5% heterospecific pollinations). Intermediate 'mother trees' were pollinated in similar proportions by Q. petraea (23.1%), Q. pubescens (37.8%) and intermediate morphotypes (39.1%). The asymmetrical introgression observed for the studied generation may be caused, among other factors, by the relative abundance of trees from each species group in the studied area.
Collapse
Affiliation(s)
- D Salvini
- Istituto per la Protezione delle Piante, Consiglio Nazionale delle Ricerche, Sesto Fiorentino, Firenze, Italy
| | | | | | | | | | | |
Collapse
|
44
|
Gaskin JF, Wheeler GS, Purcell MF, Taylor GS. Molecular evidence of hybridization in Florida's sheoak (Casuarina spp.) invasion. Mol Ecol 2009; 18:3216-26. [PMID: 19627489 DOI: 10.1111/j.1365-294x.2009.04282.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The presence of hybrids in plant invasions can indicate a potential for rapid adaptation and an added level of complexity in management of the invasion. Three Casuarina tree species, Casuarina glauca, Casuarina cunninghamiana and Casuarina equisetifolia, native to Australia, are naturalized in Florida, USA. Many Florida Casuarina trees are considered unidentifiable, presumably due to interspecific hybridization. We collected tissue from over 500 trees from Australia and Florida and genotyped these using amplified fragment length polymorphisms. Our goal was to determine the exact identity of the Florida species, including any putative hybrid combinations. In Australia, we found high assignment values to the three parental species, and no evidence of hybridization. In Florida, we found many trees with strong assignment to any one of the three species, as well as 49 trees with assignment values intermediate to C. glauca and C. equisetifolia, suggesting hybridization between these species. One population of 10 trees had assignment values intermediate to C. cunninghamiana and C. glauca, suggesting additional hybridization. For 69 of these putative hybrid and parental types, we sequenced a low-copy intron of nuclear G3pdh, and these sequences indicated that some Florida trees contain heterozygotic combinations of C. glauca and C. equisetifolia haplotypes. The presence of novel hybrids in the Florida invasion may enhance evolution of invasive traits in these species. Novel Casuarina hybrids in Florida have no coevolutionary history with any insects or diseases, which may be problematic for biological control efforts.
Collapse
Affiliation(s)
- John F Gaskin
- USDA Agricultural Research Service, Northern Plains Agricultural Research Laboratory, Sidney, MT 59270, USA.
| | | | | | | |
Collapse
|
45
|
|
46
|
Aikio S, Valosaari KR, Ranta E, Kaitala V, Lundberg P. Invasion under a trade-off between density dependence and maximum growth rate. POPUL ECOL 2008. [DOI: 10.1007/s10144-008-0085-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
47
|
Fitzpatrick BM, Shaffer HB. Introduction history and habitat variation explain the landscape genetics of hybrid tiger salamanders. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2007; 17:598-608. [PMID: 17489263 DOI: 10.1890/06-0369] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Genetic introgression from introduced species into native populations is a growing challenge for biological conservation, and one that raises unique practical and ethical issues. Here, we describe the extent of introgression between native California tiger salamanders (Ambystoma californiense) and introduced barred tiger salamanders (A. tigrinum mavortium) relative to habitat, distance from introduction sites, and watershed boundaries. We used ancestry informative markers (AIMs) to characterize the degree of introgression at 85 sites within the range of A. californiense. Eight unlinked markers showed concordant patterns, indicating that different chromosomal segments are introgressing at similar rates. The current distribution of introduced alleles is largely contained in the Salinas Valley, California. Within it, the distribution of nonnative alleles was best explained at a broad geographic scale by the history of introductions, with limited introgression beyond 12 km from multiple independent release sites. The spatial transition from highly admixed to nearly pure native populations was abrupt, suggesting either cryptic barriers to dispersal or locally rapid displacement of natives by an advancing hybrid swarm. At a more ecological level, highly modified perennial breeding ponds had higher introduced allele frequencies than more natural seasonal ponds, suggesting greater invasion success in perennial breeding ponds. Management favoring natural habitat characteristics may substantially decrease the rate of spread of introduced alleles.
Collapse
Affiliation(s)
- Benjamin M Fitzpatrick
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville 37996, USA.
| | | |
Collapse
|
48
|
KOEHLER-SANTOS PATRÍCIA, LORENZ-LEMKE ALINEP, MUSCHNER VALÉRIAC, BONATTO SANDROL, SALZANO FRANCISCOM, FREITAS LORETAB. Molecular genetic variation in Passiflora alata (Passifloraceae), an invasive species in southern Brazil. Biol J Linn Soc Lond 2006. [DOI: 10.1111/j.1095-8312.2006.00647.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
49
|
Schwartz MW, Hoeksema JD, Gehring CA, Johnson NC, Klironomos JN, Abbott LK, Pringle A. The promise and the potential consequences of the global transport of mycorrhizal fungal inoculum. Ecol Lett 2006; 9:501-15. [PMID: 16643296 DOI: 10.1111/j.1461-0248.2006.00910.x] [Citation(s) in RCA: 131] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Advances in ecology during the past decade have led to a much more detailed understanding of the potential negative consequences of species' introductions. Moreover, recent studies of mycorrhizal symbionts have led to an increased knowledge of the potential utility of fungal inoculations in agricultural, horticultural and ecological management. The intentional movement of mycorrhizal fungal species is growing, but the concomitant potential for negative ecological consequences of invasions by mycorrhizal fungi is poorly understood. We assess the degree to which introductions of mycorrhizal fungi may lead to unintended negative, and potentially costly, consequences. Our purpose is to make recommendations regarding appropriate management guidelines and highlight top priority research needs. Given the difficulty in discerning invasive species problems associated with mycorrhizal inoculations, we recommend the following. First, careful assessment documenting the need for inoculation, and the likelihood of success, should be conducted prior to inoculation because inoculations are not universally beneficial. Second, invasive species problems are costly and often impossible to control by the time they are recognized. We recommend using local inoculum sources whenever possible. Third, non-sterile cultures of inoculum can result in the movement of saprobes and pathogens as well as mutualists. We recommend using material that has been produced through sterile culture when local inoculum is not available. Finally, life-history characteristics of inoculated fungi may provide general guidelines relative to the likelihood of establishment and spread. We recommend that, when using non-local fungi, managers choose fungal taxa that carry life-history traits that may minimize the likelihood of deleterious invasive species problems. Additional research is needed on the potential of mycorrhizal fungi to spread to non-target areas and cause ecological damage.
Collapse
Affiliation(s)
- Mark W Schwartz
- Department of Environmental Science & Policy, University of California, Davis, CA, USA.
| | | | | | | | | | | | | |
Collapse
|
50
|
|