Interspecific hybridization can generate functional novelty in cichlid fish

Selz, Oliver M.; Seehausen, Ole

doi:10.1098/rspb.2019.1621

Cited by 54 publications

(69 citation statements)

References 77 publications

(138 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We cannot exclude the scenario that these phenotypes (and possibly others as well) diversified upon secondary contact and as a result of genetic admixture. This scenario was successfully tested to explain the origin of functional novelties in some cichlids 83 , and also the contemporary ecological speciation of threespined stickleback in Lake Constance 84 . The ancient hybridization between divergent lineages of cichlids was also reasonably hypothesized to fuel mega-radiations in African Great Lakes [85][86][87] .…”

Section: Discussionmentioning

confidence: 99%

In the rivers: Multiple adaptive radiations of cyprinid fishes (Labeobarbus) in Ethiopian Highlands

Левин

Simonov

Dgebuadze

et al. 2020

Sci Rep

View full text Add to dashboard Cite

Multiple repeated patterns of adaptive radiation were revealed in cyprinid fish inhabiting the compact geographic region of the ethiopian Highlands. We found four independently evolved radiations in the evolutionary hexaploid (2n = 150) Labeobarbus lineage based on matrilineal relationships of >800 individuals. Each radiation displayed similar patterns of mouth phenotype diversification, and included ecomorphs/species of the generalized, lipped, scraping (one or two), and large-mouthed (one to three) types. All radiations were detected in geographically isolated rivers, and originated from different ancestral populations. This is the first documented case in which numerous parallel radiations of fishes occurred-via different ways-in a riverine environment. Some radiations are very recent and monophyletic, while others are older and include ecomorphs that originated in separate mini flocks and later combined into one. The diversification bursts among Ethiopian Labeobarbus were detected in the mid-upper reaches of rivers (1050-1550 m above sea level), which likely offer ecological opportunities that include diverse habitats yet poor fauna (i.e. lower competition and relaxed selection). this promising example of parallel evolution of adaptive radiation warrants further investigation.In the pioneering work on South African cichlids and catfishes, Joyce et al. 21 and Day et al. 19 suggested that the riverine flocks are remnants of radiations that emerged in a paleolake. This suggestion is corroborated by the finding of the Lake Tanganyika endemics beyond the lake basin 33 . While some riverine radiations clearly have lacustrine origins, it is likely that other riverine radiations originate from sources other than lakes. Hence, we aimed to test whether the same environmental factors that trigger lacustrine radiation can also act in rivers.In general, the main prerequisites for adaptive radiation are: (1) environmental stability for evolutionarily significant periods (starting from thousands of years ago); and (2) physical isolation from the river drainages harboring diverse fish faunas 15,20,31 . The latter serves a dual purpose: first, it provides the ecological opportunities for niche divergence at the initial stages of radiation, and later it prevents the extinction of diverged forms caused by competition with highly specialized species from other systematic groups. These processes can operate in specific and rather rare parts of the riverine network. For example, the segment of the Genale River that harbours the radiating assemblage of distinct forms of the Labeobarbus is situated in the apparently old canyon, isolated by the Baratieri Falls from the lower reaches of the river system and characterized by the depauperate fish fauna 20 .If the fish radiations in rivers are similar to the evolutionary phenomena experienced in lakes, they should display similar evolutionary patterns. It is well known that adaptive radiations are often repeatable in different organisms as exemplified from spiders 34 , fish 35 , and liz...

show abstract

Section: Discussionmentioning

confidence: 99%

In the rivers: Multiple adaptive radiations of cyprinid fishes (Labeobarbus) in Ethiopian Highlands

Левин

Simonov

Dgebuadze

et al. 2020

Sci Rep

View full text Add to dashboard Cite

show abstract

“…Our meta-analysis suggests that mild forms of intrinsic incompatibilities, such as sex ratio distortion, can already be observed among closely related species (figure 2b) and potentially supplement premating barriers. Moreover, a contribution of extrinsic postzygotic isolation is likely [129,148,149]. However, the importance of these different barriers for conferring reproductive isolation can vary along the speciation continuum [163,164].…”

Section: Resultsmentioning

confidence: 99%

Evolutionary dynamics of pre- and postzygotic reproductive isolation in cichlid fishes

Rometsch

Torres‐Dowdall

Meyer

2020

Phil. Trans. R. Soc. B

View full text Add to dashboard Cite

Cichlid fishes are exceptionally species-rich, speciated at explosive rates and, hence, are a model system in speciation research. Yet, their reproductive isolating barriers have, so far, not been comprehensively studied. Here, we review current knowledge on pre- and postzygotic mechanisms in cichlids. While premating isolation is the norm in cichlids, its strength varies across lineages and with the geographical setting. Moreover, manipulations of ambient conditions tended to reduce assortative mating among closely related species, suggesting that premating isolation in cichlids is often fragile and context dependent. The observed lack of complete reproductive isolation is supported by past and present hybridization events that have contributed to diversity by creating novel allelic combinations. On the other hand, our meta-analysis highlights that intrinsic postzygotic isolation might accumulate faster than assumed. Mild forms of genetic incompatibilities, such as sex ratio distortion, can already be observed among closely related species. Therefore, cessation of gene flow by strong reproductive isolation in cichlids requires a combination of premating prezygotic isolation supplemented with intrinsic and extrinsic postzygotic barriers. Further, we suggest crucial next steps to improve our knowledge about reproductive barriers in cichlids to understand the evolutionary dynamics of pre- and postzygotic isolation mechanisms during adaptive radiations. This article is part of the theme issue ‘Towards the completion of speciation: the evolution of reproductive isolation beyond the first barriers'.

show abstract

“…There are multiple challenges in defining species, for example recently, even in defined species, fertile hybrids among plants, birds, fish, and even mammals are not uncommon [76][77][78][79], suggesting reproductive barriers may not always separate species. This may call into question as to what constitutes a species.…”

Section: Challenges and Issuesmentioning

confidence: 99%

Genomic nucleotide-based distance analysis for delimiting old world monkey derived herpes simplex virus species

Kolb

Brandt

2020

BMC Genomics

View full text Add to dashboard Cite

Background: Herpes simplex viruses form a genus within the alphaherpesvirus subfamily, with three identified viral species isolated from Old World monkeys (OWM); Macacine alphaherpesvirus 1 (McHV-1; herpes B), Cercopithecine alphaherpesvirus 2 (SA8), and Papiine alphaherpesvirus 2 (PaHV-2; herpes papio). Herpes B is endemic to macaques, while PaHV-2 and SA8 appear endemic to baboons. All three viruses are genetically and antigenically similar, with SA8 and PaHV-2 thought to be avirulent in humans, while herpes B is a biosafety level 4 pathogen. Recently, nextgeneration sequencing (NGS) has resulted in an increased number of published OWM herpes simplex genomes, allowing an encompassing phylogenetic analysis. Results: In this study, phylogenetic networks, in conjunction with a genome-based genetic distance cutoff method were used to examine 27 OWM monkey herpes simplex isolates. Genome-based genetic distances were calculated, resulting in distances between lion and pig-tailed simplex viruses themselves, and versus herpes B core strains that were higher than those between PaHV-2 and SA8 (approximately 14 and 10% respectively). The species distance cutoff was determined to be 8.94%, with the method recovering separate species status for PaHV-2 and SA8 and showed that lion and pig-tailed simplex viruses (vs core herpes B strains) were well over the distance species cutoff. Conclusions: We propose designating lion and pig-tailed simplex viruses as separate, individual viral species, and that this may be the first identification of viral cryptic species.

show abstract

Interspecific hybridization can generate functional novelty in cichlid fish

Cited by 54 publications

References 77 publications

In the rivers: Multiple adaptive radiations of cyprinid fishes (Labeobarbus) in Ethiopian Highlands

In the rivers: Multiple adaptive radiations of cyprinid fishes (Labeobarbus) in Ethiopian Highlands

Evolutionary dynamics of pre- and postzygotic reproductive isolation in cichlid fishes

Genomic nucleotide-based distance analysis for delimiting old world monkey derived herpes simplex virus species

Contact Info

Product

Resources

About