umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Colonization of the Tibetan Plateau by the homoploid hybrid pine Pinus densata
Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China. (Graduate School, Chinese Academy of Sciences, Beijing 100049, China)
(State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China)
Show others and affiliations
2011 (English)In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 20, no 18, 3796-3811 p.Article in journal (Refereed) Published
Abstract [en]

Pinus densata is an intriguingly successful homoploid hybrid species that occupies vast areas of the southeastern Tibetan Plateau in which neither of its parental species are present, but the colonization processes involved are poorly understood. To shed light on how this species colonized and became established on the plateau, we surveyed paternally inherited chloroplast (cp) and maternally inherited mitochondrial (mt) DNA variation within and among 54 populations of P. densata and its putative parental species throughout their respective ranges. Strong spatial genetic structure of both cp and mtDNA were detected in P. densata populations. Mitotypes specific to P. densata were likely generated by complex recombination events. A putative ancestral hybrid zone in the northeastern periphery of P. densata was identified, and we propose that the species then colonized the plateau by migrating westwards. Along the colonization route, consecutive bottlenecks and surfing of rare alleles caused a significant reduction in genetic diversity and strong population differentiation. The direction and intensity of introgression from parental species varied among geographic regions. In western parts of its range, the species seems to have been isolated from seed and pollen flow from its parent species for a long time. The observed spatial distribution of genetic diversity in P. densata also appears to reflect the persistence of this species on the plateau during the last glaciation. Our results indicate that both ancient and contemporary population dynamics have contributed to the spatial distribution of genetic diversity in P. densata, which accordingly reflects its evolutionary history.

Place, publisher, year, edition, pages
Leicester: Blackwell Scientific Publications , 2011. Vol. 20, no 18, 3796-3811 p.
Keyword [en]
bottleneck, colonization history, hybrid speciation, mtDNA recombination, population structure
National Category
Biological Sciences
Identifiers
URN: urn:nbn:se:umu:diva-47950DOI: 10.1111/j.1365-294X.2011.05157.xPubMedID: 21689188OAI: oai:DiVA.org:umu-47950DiVA: diva2:445618
Available from: 2011-10-04 Created: 2011-10-04 Last updated: 2017-12-08Bibliographically approved
In thesis
1. Hybridization and Evolution in the Genus Pinus
Open this publication in new window or tab >>Hybridization and Evolution in the Genus Pinus
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Gene flow and hybridization are pervasive in nature, and can lead to different evolutionary outcomes. They can either accelerate divergence and promote speciation or reverse differentiation. The process of divergence and speciation are strongly influenced by both neutral and selective forces. Disentangling the interplay between these processes in natural systems is important for understanding the general importance of interspecific gene flow in generating novel biodiversity in plants. This thesis first examines the importance of introgressive hybridization in the evolution of the genus Pinus as a whole, and then focusing on specific pine species, investigates the role of geographical, environmental and demographical factors in driving divergence and adaptation.

By examining the distribution of cytoplasmic DNA variation across the wide biogeographic range of the genus Pinus, I revealed historical introgression and mtDNA capture events in several groups of different pine species. This finding suggests that introgressive hybridization was common during past species’ range contractions and expansions and thus has played an important role in the evolution of the genus. To understand the cause and process of hybrid speciation, I focused on the significant case of hybrid speciation in Pinus densata. I established the hybridization, colonization and differentiation processes that defined the origin of this species. I found P. densata originated via multiple hybridization events in the late Miocene. The direction and intensity of introgression with two parental species varied among geographic regions of this species. During the colonization on Tibetan Plateau from the ancestral hybrid zone, consecutive bottlenecks and surfing of rare alleles caused a significant reduction in genetic diversity and strong population differentiation. Divergence within P. densata started from the late Pliocene onwards, induced by regional topographic changes and Pleistocene glaciations. To address the role of neutral and selective forces on genetic divergence, I examined the association of ecological and geographical distance with genetic distance in Pinus yunnanensis populations. I found both neutral and selective forces have contributed to population structure and differentiation in P. yunnanensis, but their relative contributions varied across the complex landscape. Finally, I evaluated genetic diversity in the Vietnamese endemic Pinus krempfii. I found extremely low genetic diversity in this species, which is explained by a small ancestral population, short-term population expansion and recent population decline and habitat fragmentation.

These findings highlight the role of hybridization in generating novel genetic diversity and the different mechanisms driving divergence and adaptation in the genus Pinus

Place, publisher, year, edition, pages
Umeå: Umeå Universitet, 2013. 49 p.
Keyword
Adaptation, biogeography, coalescent simulation, cytoplasmic genome, demographic history, genetic diversity, hybridization, migration, Pinus, population structure, selection, speciation
National Category
Evolutionary Biology
Research subject
evolutionär genetik
Identifiers
urn:nbn:se:umu:diva-80998 (URN)978-91-7459-702-8 (ISBN)
Public defence
2013-10-25, KBC-huset, KB3B1, Stora Hörsalen, Umeå Universitet, Umeå, 13:00 (English)
Opponent
Supervisors
Available from: 2013-10-04 Created: 2013-09-30 Last updated: 2013-09-30Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Authority records BETA

Wang, BaoshengWang, Xiao-Ru

Search in DiVA

By author/editor
Wang, BaoshengWang, Xiao-Ru
By organisation
Department of Ecology and Environmental Sciences
In the same journal
Molecular Ecology
Biological Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 266 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf