Wallacean and Melanesian Islands Promote Higher Rates of Diversification within the Global Passerine Radiation Corvides

Systematic Biology, Journal Year: 2022, Volume and Issue: 71(6), P. 1423 - 1439

Published: June 15, 2022

Abstract The complex island archipelagoes of Wallacea and Melanesia have provided empirical data behind integral theories in evolutionary biology, including allopatric speciation biogeography. Yet, questions regarding the relative impact layered biogeographic barriers, such as deep-water trenches isolated systems, on faunal diversification remain underexplored. One barrier is Wallace’s Line, a significant boundary that largely separates Australian Asian biodiversity. To assess roles barriers—specifically systems Line—we investigated tempo mode diverse avian radiation, Corvides (Crows Jays, Birds-of-paradise, Vangas, allies). We combined genus-level set thousands ultraconserved elements (UCEs) species-level, 12-gene Sanger sequence matrix to produce well-resolved supermatrix tree we leveraged explore group’s historical biogeography effects barriers their macroevolutionary dynamics. well resolved differs substantially from what has been used extensively for past comparative analyses within this group. confirmed Corvides, its major constituent clades, arose Australia burst dispersals west across Line occurred after uplift during mid-Miocene. found dispersal was generally rare, though westward were two times more frequent than eastward dispersals. Wallacea’s central position between Sundaland Sahul no doubt acted bridge island-hopping out Australia, colonize rest Earth. In addition, east harbor highest rates net are substantial source colonists continental both sides barrier. Our results support emerging evidence particularly geologically Indo-pacific, drivers species diversification. [Historical biogeography; Melanesia; molecular phylogenetics; state-dependent extinction.]

Language: Английский

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Population genomics of the island thrush elucidates one of earth’s great archipelagic radiations

Evolution Letters, Journal Year: 2023, Volume and Issue: unknown

Published: Jan. 31, 2023

Tropical islands are renowned as natural laboratories for evolutionary study. Lineage radiations across tropical archipelagos ideal systems investigating how colonization, speciation, and extinction processes shape biodiversity patterns. The expansion of the island thrush Indo-Pacific represents one largest yet most perplexing any songbird species. exhibits a complex mosaic pronounced plumage variation its range is arguably world's polytypic bird. It sedentary species largely restricted to mountain forests, it has colonized vast region spanning quarter globe. We conducted comprehensive sampling populations obtained genome-wide SNP data, which we used reconstruct phylogeny, population structure, gene flow, demographic history. evolved from migratory Palearctic ancestors radiated explosively during Pleistocene, with numerous instances flow between populations. Its bewildering masks biogeographically intuitive stepping stone colonization path Philippines through Greater Sundas, Wallacea, New Guinea Polynesia. thrush's success in colonizing mountains can be understood light ancestral mobility adaptation cool climates; however, shifts elevational range, degree apparent dispersal rates eastern part raise further intriguing questions about biology.

Language: Английский

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The dynamics of introgression across an avian radiation

Evolution Letters, Journal Year: 2021, Volume and Issue: 5(6), P. 568 - 581

Published: Sept. 29, 2021

Hybridization and resulting introgression can play both a destructive creative role in the evolution of diversity. Thus, characterizing when where is most likely to occur help us understand causes diversification dynamics. Here, we examine prevalence variation using phylogenomic data from large (1300+ species), geographically widespread avian group, suboscine birds. We first patterns gene tree discordance across geographic distribution entire clade. then evaluate signal subset 206 species triads Patterson's D-statistic test for associations between evolutionary, geographic, environmental variables. find that varies lineages regions. The highest cases close proximity regions with more dynamic climates since Pleistocene. Our results highlight potential datasets examining broad hybridization suggest degree diverging might be predictable based on setting which they occur.

Language: Английский

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Tramps in transition: genetic differentiation between populations of an iconic "supertramp" taxon in the Central Indo-Pacific

Frontiers of Biogeography, Journal Year: 2022, Volume and Issue: 14(2)

Published: Jan. 4, 2022

The island monarch (Monarcha cinerascens) was an original example of the “supertramp strategy”. This involves well-developed dispersal specialisation, enabling a species to colonise remote islands but leaving it competitively inferior. Supertramps are hypothesised be excluded from larger by superior competitors. It is only Melanesian supertramp occur in Wallacea, home also sedentary pale-blue (Hypothymis puella). We interrogate strategy and its biogeographical underpinnings assessing population structure these two monarchs. sampled monarchs collecting DNA morphological data. investigated applying ABGD Bayesian Maximum Likelihood methods their ND2 ND3 genes. constructed linear models investigate relationships between genetic divergence, ability, area, elevation, isolation. Wallacea’s deep waters restrict gene flow even supertramp, as Wallacean likely separate (mean distance: 2.7%). mirrors split Asia’s black-naped azurea). found further within populations. Their divergence related isolation islands, well ability birds. However, independent elevation area. Rather than being r-selected on small, disturbance-prone our results support view that monarch’s lifestyle temporary stage taxon cycle, i.e. supertramps may transition into resident after colonisation. Our suggest more dispersive reach distant promoted or permanent, without selection against per se. helps determine distribution across not necessarily occurring thereafter.

Language: Английский

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Island size shapes genomic diversity in a great speciator (Aves: Zosterops )

Biology Letters, Journal Year: 2025, Volume and Issue: 21(3)

Published: March 1, 2025

Islands have long represented natural laboratories for studying many aspects of ecology and evolutionary biology, from speciation to community assembly. One aspect that has been well documented is the correlation between island size taxonomic diversity, likely due decreased complexity population on small islands. This same logic can apply genetic which should predictably decrease with effective size. The size-diversity received support over years but often focuses single metrics diversity. Here, we use Zosterops white-eyes in Solomon study various related including runs homozygosity fixation transposable elements. We find almost all these strongly correlate size, turn each other. infer independently correlated different variables, demonstrating impacts genomic diversity a variety ways across temporal hierarchical scales.

Language: Английский

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Reconstructing the complex colonisation histories of lizards across Mediterranean archipelagos

Journal of Biogeography, Journal Year: 2023, Volume and Issue: 51(2), P. 157 - 172

Published: Oct. 10, 2023

Abstract Aim The Mediterranean Basin is a global biodiversity hotspot and has one of the longest histories human–biota interactions. Islands host large fraction diversity endemism, but relative importance natural versus human‐mediated colonisation processes in shaping distribution genetic structure island fauna remains poorly understood. Here, we combine population genomics, demographic models palaeoshoreline reconstructions to establish island‐colonisation dynamics wall lizards archipelagos. Location Four archipelagos Italy Croatia. Taxon lizard Podarcis siculus. Methods We used ddRAD sequencing genotype 140 from 23 mainland populations. Analyses admixture site frequency spectra were reconstruct structure, history variation gene flow through time. Genomic results integrated with palaeogeographical compared archaeological evidence human presence on these islands. Results Although many populations this species are assumed be non‐native, find that islands colonised long before any known settlements (230,000–12,000 years ago). This most likely occurred land bridges during glacial marine regression or by over‐sea rafting. On other hand, distant continent often recently, some estimated times match historical records arrival. also determine long‐established generally show lower proximate populations, contrary recently must have experienced higher rates post‐colonisation flow. Main Conclusion Our approach provides us power accurately quantify origin, timing mode colonisation. framework helps clarify biogeographical evolutionary important implications for conservation management biodiversity.

Language: Английский

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Phylogenomics of white-eyes, a ‘great speciator’, reveals Indonesian archipelago as the center of lineage diversity

eLife, Journal Year: 2020, Volume and Issue: 9

Published: Dec. 22, 2020

Archipelagoes serve as important 'natural laboratories' which facilitate the study of island radiations and contribute to understanding evolutionary processes. The white-eye genus Zosterops is a classical example 'great speciator', comprising c. 100 species from across Old World, most them insular. We achieved an extensive geographic DNA sampling by using historical specimens recently collected samples. Using over 700 genome-wide loci in conjunction with coalescent tree methods gene flow detection approaches, we untangled reticulated history Zosterops, comprises three main clades centered Indo-Africa, Asia, Australasia, respectively. Genetic introgression between permeates phylogeny, regardless how distantly related are. Crucially, identified Indonesian archipelago, specifically Borneo, major center diversity only area where all overlap, attesting importance this region.

Language: Английский

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Genomes From Historic DNA Unveil Massive Hidden Extinction and Terminal Endangerment in a Tropical Asian Songbird Radiation

Molecular Biology and Evolution, Journal Year: 2022, Volume and Issue: 39(9)

Published: Sept. 1, 2022

Abstract Quantifying the magnitude of global extinction crisis is important but remains challenging, as many events pass unnoticed owing to our limited taxonomic knowledge world’s organisms. The increasing rarity taxa renders comprehensive sampling difficult, further compounding problem. Vertebrate lineages such birds, which are thought be taxonomically well understood, therefore used indicator groups for mapping and quantifying extinction. To test whether patterns adequately gauged in well-studied groups, we implemented ancient-DNA protocols retrieved whole genomes from historic DNA museum specimens a widely known songbird radiation shamas (genus Copsychus) that assumed least conservation concern. We uncovered cryptic diversity an unexpected degree hidden terminal endangerment. Our analyses reveal >40% phylogenetic this already either extinct wild or nearly so, including two genomically most distinct members group (omissus nigricauda), have so far flown under radar they previously been considered subspecies. Comparing modern samples with those roughly century ago, also found significant decrease genetic concomitant increase homozygosity affecting various taxa, small-island endemics subspecies remain widespread across continental scale. application genomic approaches demonstrates elevated levels allelic loss clade has not listed globally threatened, highlighting importance ongoing reassessments incidence even animal groups. Key words: extinction, introgression, white-rumped shama, conservation.

Language: Английский

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Candidate gene polymorphisms are linked to dispersive and migratory behaviour: Searching for a mechanism behind the “paradox of the great speciators”

Journal of Evolutionary Biology, Journal Year: 2023, Volume and Issue: 36(10), P. 1503 - 1516

Published: Sept. 26, 2023

The "paradox of the great speciators" has puzzled evolutionary biologists for over half a century. A speciator requires excellent dispersal propensity to explain its occurrence on multiple islands, but reduced ability high number subspecies. rapid reduction in is often invoked solve this apparent paradox, proximate mechanism not been identified yet. Here, we explored role six genes linked migration and animal personality differences (CREB1, CLOCK, ADCYAP1, NPAS2, DRD4, SERT) 20 South Pacific populations silvereye (Zosterops lateralis) that range from highly sedentary partially migratory, determine if genetic variation associated with migration. We detected associations three genes: (i) partial migrant population, individuals had longer microsatellite alleles at CLOCK gene compared resident same population; (ii) CREB1 displayed average allele lengths recently colonized island (<200 years), evolutionarily older populations. Bayesian broken stick regression models supported length time since colonization; (iii) like CREB1, DRD4 showed polymorphisms between recent old colonizations larger sample needed confirm. SERT, NPAS2 were variable was propensity. association variants silvereyes provides impetus further exploration mechanisms underlying shifts, prospect resolving long-running paradox through lens.

Language: Английский

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Diversity patterns and speciation processes in a two‐island system with continuous migration

Evolution, Journal Year: 2022, Volume and Issue: 76(10), P. 2260 - 2271

Published: Aug. 29, 2022

Geographic isolation is a central mechanism of speciation, but perfect populations rare. Although speciation can be hindered if gene flow large, intermediate levels migration enhance by introducing genetic novelty in the semi‐isolated or founding small communities migrants. Here, we consider two‐island neutral model with continuous and study diversity patterns as function probability, population size, number genes involved reproductive (dubbed genome size). For genomes, low induce on islands that otherwise would not occur. Diversity, however, drops sharply to single species inhabiting both probability increases. large sympatric occurs even when are strictly isolated. Then richness per island increases migration, total decreases they become cosmopolitan. each there an optimal intensity for size maximizes species. We discuss observed modes induced how increase insular system while promoting asymmetry between hindering endemism.

Language: Английский

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