ARE LONG-DISTANCE DISPERSAL EVENTS IN PLANTS USUALLY CAUSED BY NONSTANDARD MEANS OF DISPERSAL?

Long-distance dispersal might be an important mechanism for the maintenance of aquatic insect populations in heterogeneous landscapes. However, these events can be difficult to measure by direct observation because the techniques can be time-consuming, expensive and technically difficult. When dispersal results in gene flow within and between populations, patterns of variation can be detected by genetic methods. The levels of population genetic structuring and the relationship between gene flow and geographical distance were assessed in the mayfly species Bungona narilla (Harker, 1957) in rainforest streams in south-east Queensland that are separated by lowland habitats. An analysis of molecular variance based on mitochondrial DNA data, using a fragment of the cytochrome oxidase I gene, revealed significant differentiation between regions, suggesting that maternal gene flow was restricted. A nested clade analysis revealed patterns of historical (contiguous) range expansions and recent restricted gene flow along with some long-distance dispersal events. Our analyses have shown that populations of B. narilla are significantly structured throughout the species range in south-east Queensland and that the low elevation habitats separating the northern and southern populations are restricting gene flow to some extent.

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Phylogeny and Biogeography of Acaena (Rosaceae) and its Relatives: Evidence of Multiple Long-Distance Dispersal Events Across the Globe

Systematic Botany ◽

10.1600/036364421x16370109698597 ◽

2021 ◽

Vol 46 (4) ◽

pp. 998-1010

Author(s):

Javier Jauregui-Lazo ◽

Daniel Potter

Keyword(s):

South Africa ◽

New Zealand ◽

Southern Hemisphere ◽

Phylogenetic Analyses ◽

Strong Support ◽

Disjunct Distribution ◽

Long Distance Dispersal ◽

Long Distance ◽

Biogeographic Patterns ◽

Dispersal Events

Abstract— Acaena (Rosaceae) is the most complex and ecologically variable genus in Sanguisorbinae. Although it has been the subject of several taxonomic treatments, the largest phylogenetic analysis to date only sampled a small fraction of the total global diversity (five to seven out of 45 to 50 species). This study included most of the species to elucidate the phylogenetic relationships of Acaena and biogeographic patterns in Sanguisorbinae. Phylogenetic analyses of non-coding nuclear (ITS region) and chloroplast (trnL-F) DNA sequence markers using maximum likelihood and Bayesian analyses suggested that Acaena is a paraphyletic group with species of Margyricarpus and Tetraglochin nested within it. We identified strong support for eight subclades that are geographically or taxonomically structured. Nevertheless, the species-level relationships within subclades are still uncertain, which may be due to rapid diversification and lack of informative characters in the markers used. Sanguisorbinae, a primarily Southern Hemisphere clade, exhibits a classic Gondwana disjunct distribution. This current distribution is explained primarily by eight long-distance dispersal events. Our results suggested that Sanguisorbinae split into Cliffortia and Acaena around 13.6 mya. While Cliffortia diversified in southern South Africa, Acaena experienced several migration events in the Southern Hemisphere. Our estimation of the ancestral range suggested that Acaena likely originated in South Africa, followed by migration and subsequent diversification into southern South America. From there, the genus migrated to New Zealand, throughout the Andes, and to tropical areas in Central America, reaching as far north as California. Chile and New Zealand are the main sources of propagules for dispersal as well as the greatest diversity for the genus. The evolutionary relationships of species in Acaena combine a history of rapid diversifications, long-distance dispersals, and genetic variation within some taxa. Further research should be undertaken to clarify the infraspecific classification of A. magellanica.

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Climate-driven vicariance and long-distance dispersal explain the Rand Flora pattern in the liverwort Exormotheca pustulosa (Marchantiophyta)

Biological Journal of the Linnean Society ◽

10.1093/biolinnean/blaa071 ◽

2020 ◽

Vol 130 (3) ◽

pp. 480-496

Author(s):

Ana Sofia Bartolomeu Rodrigues ◽

Anabela Martins ◽

César Augusto Garcia ◽

Cecília Sérgio ◽

Ron Porley ◽

...

Keyword(s):

Late Miocene ◽

Divergence Time ◽

Western Mediterranean ◽

Cape Verde ◽

Eastern Africa ◽

Disjunct Distribution ◽

Long Distance Dispersal ◽

Long Distance ◽

Divergence Time Estimates ◽

Dispersal Events

Abstract The ‘Rand flora’ is a biogeographical disjunction which refers to plant lineages occurring at the margins of the African continent and neighbouring oceanic archipelagos. Here, we tested whether the phylogeographical pattern of Exormotheca pustulosa Mitt. was the result of vicariance induced by past climatic changes or the outcome of a series of recent long-distance dispersal events. Two chloroplast markers (rps4-trnF region and psbA-trnH spacer) and one nuclear marker (ITS2) were analysed. Phylogenetic and phylogeographical relationships were inferred as well as divergence time estimates and ancestral areas. Exormotheca possibly originated in Eastern Africa during the Late Oligocene/Early Miocene while Exormotheca putulosa diversified during the Late Miocene. Three main E. pustulosa groups were found: the northern Macaronesia/Western Mediterranean, the South Africa/Saint Helena and the Cape Verde groups. The major splits among these groups occurred during the Late Miocene/Pliocene; diversification was recent, dating back to the Pleistocene. Climate-driven vicariance and subsequent long-distance dispersal events may have shaped the current disjunct distribution of E. pustulosa that corresponds to the Rand Flora pattern. Colonization of Macaronesia seems to have occurred twice by two independent lineages. The evolutionary history of E. pustulosa populations of Cape Verde warrants further study.

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Genotypes of Rhizophora Propagules From a Non-mangrove Beach Provide Evidence of Recent Long-Distance Dispersal

Frontiers in Conservation Science ◽

10.3389/fcosc.2021.746461 ◽

2021 ◽

Vol 2 ◽

Author(s):

Magdalene N. Ngeve ◽

Nico Koedam ◽

Ludwig Triest

Keyword(s):

Genetic Research ◽

Relative Difference ◽

Source Population ◽

Long Distance Dispersal ◽

Long Distance ◽

Propagule Dispersal ◽

Adult Trees ◽

Southern Cameroon ◽

Source Populations ◽

Dispersal Events

Dispersal plays a crucial role in the connectivity of established mangrove populations and in species range dynamics. As species ranges shift in response to climate change, range expansions can occur from incremental short-distance dispersal events and from stochastic long-distance dispersal events. Most population genetic research dealt with historically accumulated events though evidence of actual propagule dispersal allows to estimate genotypic features and origin of founders. In this study, we aim to disentangle a contemporary dispersal event. Using microsatellite markers, we genotyped 60 Rhizophora racemosa drift propagules obtained on a bare unforested coastal area in southern Cameroon, estimated their relationship to 109 adult trees from most proximate sites (which were 3–85 km away), and assessed their relative difference with 873 trees of major mangrove areas (> 300 km) along the Cameroonian coastline. Proximate mangrove populations were considered as potential source populations in assignment tests. However, drift propagules could not be assigned to any of the Cameroonian mangrove sites and were genetically isolated from Cameroonian populations. Drift propagules showed higher levels of genetic diversity and private alleles giving a higher relatedness to each other than to any putative source population. Chloroplast sequences were used to confirm the identity of drift propagules as R. racemosa. We postulate that a complex interaction of ocean currents, estuarine geomorphology, and tidal patterns explain drift propagule dispersal to an area. Most likely the investigated cohort of propagules originated from more southern mangrove areas of the West African range beyond the Cameroonian border. This study unraveled the allelic, genetic, and genotypic features of stranded propagules following a stochastic long-distance dispersal. Transboundary dispersal of these propagules highlights the need for intergovernmental efforts in the management of biodiversity.

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Psoroma capense and P. esterhuyseniae (Pannariaceae), two new alpine species from South Africa

The Lichenologist ◽

10.1017/s0024282920000377 ◽

2020 ◽

Vol 52 (5) ◽

pp. 345-352

Author(s):

Arve Elvebakk ◽

Soon Gyu Hong ◽

Chae Haeng Park ◽

Teppo Rämä

Keyword(s):

South Africa ◽

Secondary Compounds ◽

Western Cape ◽

Long Distance Dispersal ◽

Western Cape Province ◽

Long Distance ◽

Closely Related Species ◽

Alpine Species ◽

Recent Collection ◽

Dispersal Events

AbstractThe new species Psoroma capense and P. esterhuyseniae are described from four alpine localities in the Western Cape Province of South Africa and are the only known Psoroma species from Africa. The specimens were all collected from moist sites near watercourses, on cool and mostly south-facing cliffs. Psoroma capense resembles P. tenue in gross morphology but differs in the ascending thallus squamules, lack of secondary compounds and short-ellipsoid to ovoid ascospores. However, a phylogenetic analysis involving the markers ITS, nucLSU, mtSSU and Mcm7, comparing the only recent collection of P. capense with previously published sequences, shows that it belongs to the P. hypnorum lineage, with no known, closely related species. Psoroma esterhuyseniae resembles P. hypnorum but has subglobose to short-ellipsoid ascospores without apical perispore extensions. The two species are thought to have evolved from one or two long-distance dispersal events during the Pleistocene.

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So close and yet so far away: long‐distance dispersal events govern bryophyte metacommunity reassembly

Journal of Ecology ◽

10.1111/1365-2745.12637 ◽

2016 ◽

Vol 104 (6) ◽

pp. 1707-1719 ◽

Cited By ~ 19

Author(s):

Marion Barbé ◽

Nicole J. Fenton ◽

Yves Bergeron

Keyword(s):

Long Distance Dispersal ◽

Long Distance ◽

Dispersal Events

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Identification of group A rotaviruses from Zambian fruit bats provides evidence for long-distance dispersal events in Africa

Infection Genetics and Evolution ◽

10.1016/j.meegid.2018.05.016 ◽

2018 ◽

Vol 63 ◽

pp. 104-109 ◽

Cited By ~ 5

Author(s):

Michihito Sasaki ◽

Masahiro Kajihara ◽

Katendi Changula ◽

Akina Mori-Kajihara ◽

Hirohito Ogawa ◽

...

Keyword(s):

Long Distance Dispersal ◽

Fruit Bats ◽

Long Distance ◽

Group A Rotaviruses ◽

Group A ◽

Dispersal Events

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Global Diversification of Anelosimus Spiders Driven by Long-Distance Overwater Dispersal and Neogene Climate Oscillations

Systematic Biology ◽

10.1093/sysbio/syaa017 ◽

2020 ◽

Vol 69 (6) ◽

pp. 1122-1136 ◽

Cited By ~ 1

Author(s):

Yufa Luo ◽

Seok P Goh ◽

Daiqin Li ◽

Marcelo O Gonzaga ◽

Adalberto J Santos ◽

...

Keyword(s):

South America ◽

Molecular Phylogenetics ◽

Causal Connection ◽

Long Distance Dispersal ◽

Long Distance ◽

Early Diversification ◽

Nucleotide Data ◽

Major Factors ◽

Climatic Cooling ◽

Dispersal Events

Abstract Vicariance and dispersal events, combined with intricate global climatic history, have left an imprint on the spatiotemporal distribution and diversity of many organisms. Anelosimus cobweb spiders (Theridiidae), are organisms ranging in behavior from solitary to highly social, with a cosmopolitan distribution in temperate to tropical areas. Their evolutionary history and the discontinuous distribution of species richness suggest that 1) long-distance overwater dispersal and 2) climate change during the Neogene (23–2.6 Ma), may be major factors in explaining their distribution and diversification. Here, we test these hypotheses, and explicitly test if global Miocene/Pliocene climatic cooling in the last 8 Ma affected Anelosimus radiation in parallel in South America and Madagascar. To do so, we investigate the phylogeny and spatiotemporal biogeography of Anelosimus through a culmination of a 20-year comprehensive global sampling at the species level (69 species, including 84% of the known 75 species worldwide, represented by 268 individuals) using nucleotide data from seven loci (5.5 kb). Our results strongly support the monophyly of Anelosimus with an Oligocene ($\sim $30 Ma) South American origin. Major clades on other continents originate via multiple, long-distance dispersal events, of solitary or subsocial—but not social—lineages, from the Americas. These intercontinental dispersals were to Africa, Madagascar (twice), and SE Asia/Australasia. The early diversification of Anelosimus spiders coincides with a sudden thermal increase in the late Oligocene ($\sim $27–25 Ma), though no causal connection can be made. Our results, however, strongly support the hypothesis that global Neogene climatic cooling in the last 8 Ma drove Anelosimus radiation in parallel in South America and Madagascar, offering a rare empirical evidence for diversification of a socially diverse group driven by an interplay between long-distance dispersal and global Neogene climatic changes. [Cobweb spiders; diversification; global biogeography; long-distance dispersal; molecular phylogenetics; neogene climate changes; sociality; vicariance.]

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