Cladistic species definitions can lead to under-representation of biodiversity from adaptive radiations

Evolutionary Journal of the Linnean Society, Год журнала: 2024, Номер 3(1)

Опубликована: Янв. 1, 2024

Abstract Many species are paraphyletic, but current taxonomic practices often do not recognize this, and attempts made to apply a monophyletic concept. While allowing the recognition of ecomorphologically equivalent, or even phenotypically indistinguishable allopatric, taxa as species, this leads combining distinctive local forms (such cave-adapted populations) whole adaptive radiations (often in lakes) with widespread paraphyletic force monophyly. It is suggested that has negative consequences for our documentation understanding biodiversity, well conservation, through issues such lack IUCN red-listing.

Язык: Английский

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Newly discovered cichlid fish biodiversity threatened by hybridization with non‐native species

Molecular Ecology, Год журнала: 2020, Номер 30(4), С. 895 - 911

Опубликована: Окт. 16, 2020

Abstract Invasive freshwater fishes are known to readily hybridize with indigenous congeneric species, driving loss of unique and irreplaceable genetic resources. Here we reveal that newly discovered (2013–2016) evolutionarily significant populations Korogwe tilapia ( Oreochromis korogwe ) from southern Tanzania threatened by hybridization the larger invasive Nile niloticus ). We use a combination morphology, microsatellite allele frequencies whole genome sequences show O. lakes (Nambawala, Rutamba Mitupa) distinct geographically disjunct in northern (Zigi River Mlingano Dam). also provide evidence × hybrids three demonstrate heterogeneity extent admixture across genome. Finally, using least admixed genomic regions estimate most plausibly diverged ~140,000 years ago, suggesting geographical separation groups is not result recent translocation, instead these represent independent units. conclude phenotypically cichlid already an propose resources would benefit conservation interventions.

Язык: Английский

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Mapping epigenetic divergence in the massive radiation of Lake Malawi cichlid fishes

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Окт. 7, 2021

Abstract Epigenetic variation modulates gene expression and can be heritable. However, knowledge of the contribution epigenetic divergence to adaptive diversification in nature remains limited. The massive evolutionary radiation Lake Malawi cichlid fishes displaying extensive phenotypic diversity despite extremely low sequence is an excellent system study epigenomic adaptation. Here, we present a comparative genome-wide methylome transcriptome study, focussing on liver muscle tissues phenotypically divergent species. In both find substantial among Differentially methylated regions (DMR), enriched young transposons, are associated with transcription changes ecologically-relevant genes related energy expenditure lipid metabolism, pointing link between dietary ecology divergence. Unexpectedly, half all species-specific DMRs shared across developmental genes, likely reflecting distinct programmes. Our reveals closely-related represents resource role epigenetics species diversification.

Язык: Английский

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Genetic basis of ecologically relevant body shape variation among four genera of cichlid fishes

Molecular Ecology, Год журнала: 2023, Номер 32(14), С. 3975 - 3988

Опубликована: Май 10, 2023

Abstract Divergence in body shape is one of the most widespread and repeated patterns morphological variation fishes associated with habitat specification swimming mechanics. Such ecological diversification first stage explosive adaptive radiation cichlid East African Rift Lakes. We use two hybrid crosses cichlids ( Metriaclima sp . × Aulonocara sp. Labidochromis Labeotropheus sp., >975 animals total) to determine genetic basis that similar benthic‐pelagic divergence across fishes. Using a series both linear geometric measurements, we identified 34 quantitative trait loci (QTL) underlie various aspects variation. These QTL are spread throughout genome, each explaining 3.2–8.6% phenotypic variation, largely modular. Further, distinct between these Lake Malawi compared previously for such as sticklebacks. find controlled by many genes small effect. In all, convergent phenotypes commonly observed fish clades likely due molecular mechanisms.

Язык: Английский

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A structured coalescent model reveals deep ancestral structure shared by all modern humans

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Март 27, 2024

1 Abstract Understanding the series of admixture events and population size history leading to modern humans is central human evolutionary genetics. Using a coalescence-based hidden Markov model, we present evidence for an extended period structure in all humans, which two ancestral populations that diverged ∼1.5 million years ago came together event ∼300 thousand ago, ratio ∼80:20 percent. Immediately after their divergence, detect strong bottleneck major population. We inferred regions present-day genome derived from each population, finding material minority correlates strongly with distance coding sequence, suggesting it was deleterious against majority background. Moreover, found correlation between ancestry human-Neanderthal or human-Denisovan also those archaic humans.

Язык: Английский

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