scholarly journals Diversification of mandarin citrus by hybrid speciation and apomixis

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Guohong Albert Wu ◽  
Chikatoshi Sugimoto ◽  
Hideyasu Kinjo ◽  
Chika Azama ◽  
Fumimasa Mitsube ◽  
...  
Keyword(s):  
Genome Analysis ◽  
East Asian ◽  
Ryukyu Islands ◽  
Hybrid Speciation ◽  
Comparative Genome Analysis ◽  
Hybrid Species ◽  
The Ryukyu Islands ◽  
Homoploid Hybrid ◽  
Rapid Diffusion ◽  
Apomictic Reproduction

AbstractThe origin and dispersal of cultivated and wild mandarin and related citrus are poorly understood. Here, comparative genome analysis of 69 new east Asian genomes and other mainland Asian citrus reveals a previously unrecognized wild sexual species native to the Ryukyu Islands: C. ryukyuensis sp. nov. The taxonomic complexity of east Asian mandarins then collapses to a satisfying simplicity, accounting for tachibana, shiikuwasha, and other traditional Ryukyuan mandarin types as homoploid hybrid species formed by combining C. ryukyuensis with various mainland mandarins. These hybrid species reproduce clonally by apomictic seed, a trait shared with oranges, grapefruits, lemons and many cultivated mandarins. We trace the origin of apomixis alleles in citrus to mangshanyeju wild mandarins, which played a central role in citrus domestication via adaptive wild introgression. Our results provide a coherent biogeographic framework for understanding the diversity and domestication of mandarin-type citrus through speciation, admixture, and rapid diffusion of apomictic reproduction.

The Quasi-War in East Asia: Japan's Expedition to Taiwan and the Ryūkyū Controversy

1983 ◽  
Vol 17 (2) ◽  
pp. 257-281 ◽  
Author(s):  
Edwin Pak-Wah Leung
Keyword(s):  
East Asia ◽  
East Asian ◽  
Ryukyu Islands ◽  
Asian Countries ◽  
Political Status ◽  
The Ryukyu Islands ◽  
Japanese Subjects

AbstractThe 1870s witnessed mounting tension among East Asian countries. In 1874,. Japan sent an expeditionary force to Taiwan to punish the aborigines there who had, in 1871, killed fifty-four shipwrecked Ryūkyūans (Liu-ch'iuans). By doing so, according to many scholars today, Japan was able to claim retroactively that the Ryūkyūan castaways were legally Japanese subjects, thereby ending the Sino-Japanese dispute over the ambiguous political status of the Ryūkyū Islands (the Chūzan Kingdom of Ryūkyū paid tribute to both China and the Satsuma-han of Japan before the 18705).This paper is a reappraisal of this episode of the ‘Quasi-war’ in East Asia. By going into the Chinese, Japanese, Ryūkyūan, and Western sources, it unfolds some unknown events which directly and indirectly led to the Japanese decision to send forces to Taiwan, as well as the Chinese reactions. The conclusion of this paper refutes the customary view which holds that China had in 1874 ‘renounced her claim over Ryūkyū and yielded to the Japanese claim she had earlier disputed.’ As this paper will show, neither Soejima Taneomi nor Ōkubo Toshimichi had succeeded in securing any Chinese endorsement of Japan's sovereign right over Ryūky¯. Nor did the Sino-Japanese Treaty of 1874, concerning the settlement of the Taiwan crisis, legally settle the Ryūkyū problem, since Ryūky¯ was never mentioned in the Treaty. As a result, the issue continued to trouble Peking and Tokyo in the years that immediately followed.

scholarly journals Genetic divergence and the number of hybridizing species affect the path to homoploid hybrid speciation

2018 ◽  
Vol 115 (39) ◽  
pp. 9761-9766 ◽  
Author(s):  
Aaron A. Comeault ◽  
Daniel R. Matute
Keyword(s):  
Genetic Diversity ◽  
Reproductive Isolation ◽  
Genetic Divergence ◽  
Adaptive Systems ◽  
Parental Species ◽  
Hybrid Speciation ◽  
Hybrid Species ◽  
Empirical Question ◽  
Homoploid Hybrid

Hybridization is often maladaptive and in some instances has led to the loss of biodiversity. However, hybridization can also promote speciation, such as during homoploid hybrid speciation, thereby generating biodiversity. Despite examples of homoploid hybrid species, the importance of hybridization as a speciation mechanism is still widely debated, and we lack a general understanding of the conditions most likely to generate homoploid hybrid species. Here we show that the level of genetic divergence between hybridizing species has a large effect on the probability that their hybrids evolve reproductive isolation. We find that populations of hybrids formed by parental species with intermediate levels of divergence were more likely to mate assortatively, and discriminate against their parental species, than those generated from weakly or strongly diverged parental species. Reproductive isolation was also found between hybrid populations, suggesting differential sorting of parental traits across populations. Finally, hybrid populations derived from three species were more likely to evolve reproductive isolation than those derived from two species, supporting arguments that hybridization-supplied genetic diversity can lead to the evolution of novel “adaptive systems” and promote speciation. Our results illustrate when we expect hybridization and admixture to promote hybrid speciation. Whether homoploid hybrid speciation is a common speciation mechanism in general remains an outstanding empirical question.

scholarly journals Hybridization and genome evolution I: The role of contingency during hybrid speciation

2013 ◽  
Vol 59 (5) ◽  
pp. 667-674 ◽  
Author(s):  
Fabrice Eroukhmanoff ◽  
Richard I. Bailey ◽  
Glenn-Peter Sætre
Keyword(s):  
Chromosome Number ◽  
Genome Evolution ◽  
Hybrid Speciation ◽  
Parent Species ◽  
Large Role ◽  
Hybrid Species ◽  
Intragenomic Conflict ◽  
Hybrid Swarms ◽  
Homoploid Hybrid

Abstract Homoploid hybrid speciation (HHS) involves the recombination of two differentiated genomes into a novel, functional one without a change in chromosome number. Theoretically, there are numerous ways for two parental genomes to recombine. Hence, chance may play a large role in the formation of a hybrid species. If these genome combinations can evolve rapidly following hybridization and sympatric situations are numerous, recurrent homoploid hybrid speciation is a possibility. We argue that three different, but not mutually exclusive, types of contingencies could influence this process. First, many of these “hopeful monsters” of recombinant parent genotypes would likely have low fitness. Only specific combinations of parental genomic contributions may produce viable, intra-fertile hybrid species able to accommodate potential constraints arising from intragenomic conflict. Second, ecological conditions (competition, geography of the contact zones or the initial frequency of both parent species) might favor different outcomes ranging from sympatric coexistence to the formation of hybrid swarms and ultimately hybrid speciation. Finally, history may also play an important role in promoting or constraining recurrent HHS if multiple hybridization events occur sequentially and parental divergence or isolation differs along this continuum. We discuss under which conditions HHS may occur multiple times in parallel and to what extent recombination and selection may fuse the parent genomes in the same or different ways. We conclude by examining different approaches that might help to solve this intriguing evolutionary puzzle.

scholarly journals Speciation driven by hybridization and chromosomal plasticity in a wild yeast

2015 ◽  
Author(s):  
Jean-Baptiste Leducq ◽  
Lou Nielly-Thibault ◽  
Guillaume Charron ◽  
Chris Eberlein ◽  
Jukka-Pekka Verta ◽  
...  
Keyword(s):  
Rapid Evolution ◽  
Natural Populations ◽  
Secondary Contact ◽  
Hybrid Speciation ◽  
Hybrid Species ◽  
Chromosome Architecture ◽  
The North ◽  
Wild Yeast ◽  
Homoploid Hybrid ◽  
Powerful Mechanism

Hybridization is recognized as a powerful mechanism of speciation and a driving force in generating biodiversity. However, only few multicellular species, limited to a handful of plants and animals, have been shown to fulfill all the criteria of homoploid hybrid speciation. This lack of evidence could lead to the misconception that speciation by hybridization has a limited role in eukaryotes, particularly in single-celled organisms. Laboratory experiments have revealed that fungi such as budding yeasts can rapidly develop reproductive isolation and novel phenotypes through hybridization, showing that in principle homoploid speciation could occur in nature. Here we report a case of homoploid hybrid speciation in natural populations of the budding yeast Saccharomyces paradoxus inhabiting the North American forests. We show that the rapid evolution of chromosome architecture and an ecological context that led to secondary contact between nascent species drove the formation of an incipient hybrid species with a potentially unique ecological niche.

Founding of the Ming Dynasty and the Rise of the Ryukyu Kingdom

2016 ◽  
Author(s):  
Mamoru Akamine
Keyword(s):  
Ming Dynasty ◽  
East Asian ◽  
Trading Partner ◽  
Ryukyu Islands ◽  
Okinawa Island ◽  
Conventional View ◽  
The Ryukyu Islands ◽  
Tribute System ◽  
And Control ◽  
The Ming Dynasty

With the establishment of the Ming Dynasty, Emperor Hongwu announced a ban on sea travel to try and control wakō pirates. He established a tribute system whereby countries that accepted the Chinese emperor as sovereign could send tribute trade missions to and from China. Because the pirates frequented the Ryukyu Islands, Hongwu had a preference policy toward Ryukyu to obtain their help in controlling wakō pirates. Of the three domains dominating Okinawa Island, Chūzan emerged as China’s main trading partner, and this began the process of unifying the Ryukyu Kingdom. A number of Chinese merchants, traditionally known as “the Thirty-six Families” relocated to Ryukyu to facilitate tribute trade, though the author disputes the conventional view of this as a “gift” from China. By the end of the chapter, Ryukyu is poised to be a key player – a cornerstone – in the East Asian trade sphere.

scholarly journals The genomic and ecological context of hybridization affect the probability that symmetrical incompatibilities drive hybrid speciation

2017 ◽  
Author(s):  
Aaron A. Comeault
Keyword(s):  
Hybrid Zone ◽  
Genetic Architecture ◽  
Theoretical Work ◽  
Hybrid Speciation ◽  
Parent Species ◽  
Ecological Context ◽  
Linear Arrangement ◽  
Hybrid Species ◽  
Homoploid Hybrid ◽  
Linkage Relationships

AbstractDespite examples of homoploid hybrid species, theoretical work describing when, where, and how we expect homoploid hybrid speciation to occur remains relatively rare. Here I explore the probability of homoploid hybrid speciation due to “symmetrical incompatibilities” under different selective and genetic scenarios. Through simulation, I test how genetic architecture and selection acting on traits that do not themselves generate incompatibilities interact to affect the probability that hybrids evolve symmetrical incompatibilities with their parent species. Unsurprisingly, selection against admixture at ‘adaptive’ loci that are linked to loci that generate incompatibilities tends to reduce the probability of evolving symmetrical incompatibilities. By contrast, selection that favors admixed genotypes at adaptive loci can promote the evolution of symmetrical incompatibilities. The magnitude of these outcomes is affected by the strength of selection, aspects of genetic architecture such as linkage relationships and the linear arrangement of loci along a chromosome, and the amount of hybridization following the formation of a hybrid zone. These results highlight how understanding the nature of selection, aspects of the genetics of traits affecting fitness, and the strength of reproductive isolation between hybridizing taxa can all be used to inform when we expect to observe homoploid hybrid speciation due to symmetrical incompatibilities.

scholarly journals The role of parental and hybrid species in multiple introgression events: evidence of homoploid hybrid speciation inCentaurea(Cardueae, Asteraceae)

2014 ◽  
Vol 175 (3) ◽  
pp. 453-467 ◽  
Author(s):  
Giulia Mameli ◽  
Javier López-Alvarado ◽  
Emmanuele Farris ◽  
Alfonso Susanna ◽  
Rossella Filigheddu ◽  
...  
Keyword(s):  
Hybrid Speciation ◽  
Hybrid Species ◽  
Homoploid Hybrid

The Gusuku Period

2016 ◽  
Author(s):  
Mamoru Akamine
Keyword(s):  
East Asia ◽  
Fifteenth Century ◽  
East Asian ◽  
Ryukyu Islands ◽  
High Demand ◽  
The Ryukyu Islands

This chapter looks at the Gusuku period (roughly the fifteenth century), when Ryukyu was divided into two cultural spheres – northern and southern. This period saw the rise of local fiefs, and increased trade between them and others in East Asia (Japan, China, Korea, etc.). The chapter describes how Song China developed an East Asian Trade sphere that encompassed all the surrounding countries, including the various fiefdoms in the Ryukyu Islands. The Ryukyus specialized in sulphur and mother-of-pearl, both in high demand in the region. As Japan ceased trading directly with China, Ryukyu became an important go-between.

scholarly journals Phylogenomic insights into the divergent history and hybridization within the East Asian endemic Abelia (Caprifoliaceae)

2021 ◽  
Author(s):  
Qinghui Sun ◽  
Diego F Morales-Briones ◽  
Hongxin Wang ◽  
Jacob F. Landis ◽  
Jun Wen ◽  
...  
Keyword(s):  
Phylogenetic Relationships ◽  
East Asian ◽  
Network Evolution ◽  
Disjunct Distribution ◽  
Ryukyu Islands ◽  
Last Interglacial ◽  
Niche Modelling ◽  
Range Contraction ◽  
Biogeographic History ◽  
The Ryukyu Islands

Background and Aims Abelia (Caprifoliaceae) is a small genus with five species (including one artificial hybrid). The genus has a disjunct distribution across mainland China, Taiwan and the Ryukyu Islands, providing a model system to explore species dispersal mechanisms of the East Asian flora. However, the current phylogenetic relationships within Abelia remain controversial. Methods In this study, we reconstructed the phylogenetic relationships within Abelia using nuclear loci generated by target enrichment and the cpDNA from genome skimming. Key Results: We found large cytonuclear discordance across the genus. Based on the nuclear and chloroplast phylogenies we proposed to merge A. schumannii into A. macrotera, and A. macrotera var. mairei into A. uniflora. Divergence time estimation, ancestral area reconstruction, and ecological niche modelling (ENM) were used to examine the biogeographic history of Abelia. Our results showed that Abelia originated in Southwest China, and diversification began in the Early Eocene, followed by A. chinensis var. ionandra colonizing Taiwan in the Middle Miocene. The ENM results suggested an expansion of climatically suitable areas during the Last Glacial Maximum and range contraction during the Last Interglacial. Disjunction between the Himalaya-Hengduan Mountain region (HHM) and Taiwan is most likely the consequence of topographic isolation and postglacial contraction. Conclusions Overall, our results supports that postglacial range contraction together with topographic heterogeneity resulted in the Taiwan and China mainland disjunction. Furthermore, when we using genome data to reconstruct the phylogeny of related species, branch evolution and network evolution should be considered, as well as gene flow in historical periods. This research provide new insights for the speciation process and taxonomy of Abelia.

Sign in / Sign up

Export Citation Format

Share Document