Social aspects of sport

xiv, 350 p.; 21 cm

Data from: Genomic architecture of ecologically divergent body shape in a pair of sympatric crater lake cichlid fishes

Determining the genetic bases of adaptations and their roles in speciation are prominent issues in evolutionary biology. Cichlid fish species flocks are a prime example of recent rapid radiations often associated with adaptive phenotypic divergence from a common ancestor within a short period of time. In several radiations of freshwater fishes divergence in eco-morphological traits including body shape, color, lips and jaws, are thought to underlie their ecological differentiation, specialization and – ultimately – speciation. The Midas cichlid species complex (Amphilophus spp.) of Nicaragua provides one of the few known examples of sympatric speciation where species have rapidly evolved different but parallel morphologies in young crater lakes. This study identified significant QTL for body shape, using SNPs generated via ddRAD sequencing and geometric morphometric analyses of a cross between two ecologically and morphologically divergent, sympatric cichlid species endemic to crater Lake Apoyo: an elongated limnetic species (A. zaliosus) and a high-bodied benthic species (A. astorquii). A total of 453 genome-wide informative SNPs were identified in 240 F2 hybrids. These markers were used to construct a genetic map in which 25 linkage groups were resolved. Seventy-two segregating SNPs were linked to 11 QTL. By annotating the two most highly supported QTL-linked genomic regions, genes that might contribute to divergence in body shape along the benthic-limnetic axis in Midas cichlid sympatric adaptive radiations were identified. These results suggest that few genomic regions of large effect contribute to early-stage divergence in Midas cichlids

Parallel evolution of Nicaraguan crater lake cichlid fishes via non-parallel routes

Fundamental to understanding how biodiversity arises and adapts is whether evolution is predictable in the face of stochastic genetic and demographic factors. Here we show rapid parallel evolution across two closely related but geographically isolated radiations of Nicaraguan crater lake cichlid fishes. We find significant morphological, ecological and genetic differentiation between ecomorphs in sympatry, reflected primarily in elongated versus high-bodied shape, differential ecological niche use and genetic differentiation. These eco-morphological divergences are significantly parallel across radiations. Based on 442,644 genome-wide single nucleotide polymorphisms, we identify strong support for the monophyly of, and subsequent sympatric divergence within, each radiation. However, the order of speciation differs across radiations; in one lake the limnetic ecomorph diverged first while in the other a benthic ecomorph. Overall our results demonstrate that complex parallel phenotypes can evolve very rapidly and repeatedly in similar environments, probably due to natural selection, yet this evolution can proceed along different evolutionary genetic routes

Sample_Info

Description of the dataset. For each individual (F2 progeny or Parent), the barcode used and the Illumina RAD library are provided

Data from: Genomic architecture of ecologically divergent body shape in a pair of sympatric crater lake cichlid fishes

Determining the genetic bases of adaptations and their roles in speciation are prominent issues in evolutionary biology. Cichlid fish species flocks are a prime example of recent rapid radiations often associated with adaptive phenotypic divergence from a common ancestor within a short period of time. In several radiations of freshwater fishes divergence in eco-morphological traits including body shape, color, lips and jaws, are thought to underlie their ecological differentiation, specialization and – ultimately – speciation. The Midas cichlid species complex (Amphilophus spp.) of Nicaragua provides one of the few known examples of sympatric speciation where species have rapidly evolved different but parallel morphologies in young crater lakes. This study identified significant QTL for body shape, using SNPs generated via ddRAD sequencing and geometric morphometric analyses of a cross between two ecologically and morphologically divergent, sympatric cichlid species endemic to crater Lake Apoyo: an elongated limnetic species (A. zaliosus) and a high-bodied benthic species (A. astorquii). A total of 453 genome-wide informative SNPs were identified in 240 F2 hybrids. These markers were used to construct a genetic map in which 25 linkage groups were resolved. Seventy-two segregating SNPs were linked to 11 QTL. By annotating the two most highly supported QTL-linked genomic regions, genes that might contribute to divergence in body shape along the benthic-limnetic axis in Midas cichlid sympatric adaptive radiations were identified. These results suggest that few genomic regions of large effect contribute to early-stage divergence in Midas cichlids

Genotypes

Genotype information in "loc" format (JoinMap) of the 220 F2 individuals used in the QTL mapping

Raw_Coordinates

Raw x,y coordinates for the landmarks and semilandmarks of the individuals used for QTL mapping. Phenotype missing for specimen 628

Degradation, Harm and Survival in a Women’s Prison:Special Issue on Gendered Violence

The study of parallel evolution facilitates the discovery of common rules of diversification. Here, we examine the repeated evolution of thick lips in Midas cichlid fishes (the Amphilophus citrinellus species complex)—from two Great Lakes and two crater lakes in Nicaragua—to assess whether similar changes in ecology, phenotypic trophic traits and gene expression accompany parallel trait evolution. Using next-generation sequencing technology, we characterize transcriptome-wide differential gene expression in the lips of wild-caught sympatric thick- and thin-lipped cichlids from all four instances of repeated thick-lip evolution. Six genes (apolipoprotein D, myelin-associated glycoprotein precursor, four-and-a-half LIM domain protein 2, calpain-9, GTPase IMAP family member 8-like and one hypothetical protein) are significantly underexpressed in the thick-lipped morph across all four lakes. However, other aspects of lips' gene expression in sympatric morphs differ in a lake-specific pattern, including the magnitude of differentially expressed genes (97-510). Generally, fewer genes are differentially expressed among morphs in the younger crater lakes than in those from the older Great Lakes. Body shape, lower pharyngeal jaw size and shape, and stable isotopes (δ13C and δ15N) differ between all sympatric morphs, with the greatest differentiation in the Great Lake Nicaragua. Some ecological traits evolve in parallel (those related to foraging ecology; e.g. lip size, body and head shape) but others, somewhat surprisingly, do not (those related to diet and food processing; e.g. jaw size and shape, stable isotopes). Taken together, this case of parallelism among thick- and thin-lipped cichlids shows a mosaic pattern of parallel and nonparallel evolution