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Darrin Hulsey C, Zheng J, Holzman R, Alfaro ME, Olave M, Meyer A. Phylogenomics of a putatively convergent novelty: did hypertrophied lips evolve once or repeatedly in Lake Malawi cichlid fishes? BMC Evol Biol 2018; 18:179. [PMID: 30486792 PMCID: PMC6263179 DOI: 10.1186/s12862-018-1296-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 11/16/2018] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Phylogenies provide critical information about convergence during adaptive radiation. To test whether there have been multiple origins of a distinctive trophic phenotype in one of the most rapidly radiating groups known, we used ultra-conserved elements (UCEs) to examine the evolutionary affinities of Lake Malawi cichlids lineages exhibiting greatly hypertrophied lips. RESULTS The hypertrophied lip cichlids Cheilochromis euchilus, Eclectochromis ornatus, Placidochromis "Mbenji fatlip", and Placidochromis milomo are all nested within the non-mbuna clade of Malawi cichlids based on both concatenated sequence and single nucleotide polymorphism (SNP) inferred phylogenies. Lichnochromis acuticeps that exhibits slightly hypertrophied lips also appears to have evolutionary affinities to this group. However, Chilotilapia rhoadesii that lacks hypertrophied lips was recovered as nested within the species Cheilochromis euchilus. Species tree reconstructions and analyses of introgression provided largely ambiguous patterns of Malawi cichlid evolution. CONCLUSIONS Contrary to mitochondrial DNA phylogenies, bifurcating trees based on our 1024 UCE loci supported close affinities of Lake Malawi lineages with hypertrophied lips. However, incomplete lineage sorting in Malawi tends to render these inferences more tenuous. Phylogenomic analyses will continue to provide powerful inferences about whether phenotypic novelties arose once or multiple times during adaptive radiation.
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Affiliation(s)
- C. Darrin Hulsey
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Jimmy Zheng
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, CA USA
| | - Roi Holzman
- Department of Zoology, Tel Aviv University and the Inter-University Institute for Marine Sciences in Eilat, 88103 Eilat, Israel
| | - Michael E. Alfaro
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, CA USA
| | - Melisa Olave
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Axel Meyer
- Department of Biology, University of Konstanz, Konstanz, Germany
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Bbole I, Zhao JL, Tang SJ, Katongo C. Mitochondrial genome annotation and phylogenetic placement of Oreochromis andersonii and O. macrochir among the cichlids of southern Africa. PLoS One 2018; 13:e0203095. [PMID: 30481181 PMCID: PMC6258479 DOI: 10.1371/journal.pone.0203095] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Accepted: 11/12/2018] [Indexed: 11/18/2022] Open
Abstract
Genetic characterization of southern African cichlids has not received much attention. Here, we describe the mitogenome sequences and phylogenetic positioning of Oreochromis andersonii and O. macrochir among the African cichlids. The complete mitochondrial DNA sequences were determined for O. andersonii and O. macrochir, two important aquaculture and fisheries species endemic to southern Africa. The complete mitogenome sequence lengths were 16642 bp and 16644 bp for O. andersonii and O. macrochir respectively. The general structural organization follows that of other teleost species with 13 protein-coding genes, 2 rRNAs, 22 tRNAs and a non-coding control region. Phylogenetic placement of the two species among other African cichlids was performed using Maximum Likelihood (ML) and Bayesian Markov-Chain-Monte-Carlo (MCMC). The consensus trees confirmed the relative positions of the two cichlid species with O. andersonii being very closely related to O. mossambicus and O. macrochir showing a close relation to both species. Among the 13 mitochondrial DNA protein coding genes ND6 may have evolved more rapidly and COIII was the most conserved. There are signs that ND6 may have been subjected to positive selection in order for these cichlid lineages to diversify and adapt to new environments. More work is needed to characterize the southern Africa cichlids as they are important species for capture fisheries, aquaculture development and understanding biogeographic history of African cichlids. Bio-conservation of some endangered cichlids is also essential due to the threat by invasive species.
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Affiliation(s)
- Ian Bbole
- Department of Fisheries, Mansa, Zambia
- Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai Ocean University, Shanghai, China
| | - Jin-Liang Zhao
- Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai Ocean University, Shanghai, China
- Centre for Research on Environmental Ecology and Fish Nutrition (CREEFN), Ministry of Agriculture, Shanghai Ocean University, Shanghai, China
- National Demonstration Centre for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Shou-Jie Tang
- Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai Ocean University, Shanghai, China
| | - Cyprian Katongo
- Biological Sciences Department, University of Zambia, Lusaka, Zambia
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Hulsey CD, Zheng J, Faircloth BC, Meyer A, Alfaro ME. Phylogenomic analysis of Lake Malawi cichlid fishes: Further evidence that the three-stage model of diversification does not fit. Mol Phylogenet Evol 2017; 114:40-48. [DOI: 10.1016/j.ympev.2017.05.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 05/14/2017] [Accepted: 05/30/2017] [Indexed: 01/05/2023]
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Holzman R, Hulsey CD. Mechanical Transgressive Segregation and the Rapid Origin of Trophic Novelty. Sci Rep 2017; 7:40306. [PMID: 28079133 PMCID: PMC5228120 DOI: 10.1038/srep40306] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 12/05/2016] [Indexed: 01/09/2023] Open
Abstract
Hybrid phenotypes are often intermediate between those of parental species. However, hybridization can generate novel phenotypes when traits are complex. For instance, even when the morphologies of individual musculo-skeletal components do not segregate outside the parental range in hybrid offspring, complex functional systems can exhibit emergent phenotypes whose mechanics exceed the parental values. To determine if transgression in mechanics could facilitate divergence during an adaptive radiation, we examined three functional systems in the trophic apparatus of Lake Malawi cichlid fishes. We conducted a simulation study of hybridization between species pairs whose morphology for three functional systems was empirically measured, to determine how the evolutionary divergence of parental species influences the frequency that hybridization could produce mechanics that transgress the parental range. Our simulations suggest that the complex mechanical systems of the cichlid trophic apparatus commonly exhibit greater transgression between more recently diverged cichlid species. Because (1) all three mechanical systems produce hybrids with transgressive mechanics in Lake Malawi cichlids, (2) hybridization is common, and (3) single hybrid crosses often recapitulate a substantial diversity of mechanics, we conclude that mechanical transgressive segregation could play an important role in the rapid accumulation of phenotypic variation in adaptive radiations.
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Affiliation(s)
- Roi Holzman
- Department of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
- The Inter-University Institute for Marine Sciences, POB 469, Eilat 88103, Israel
| | - C. Darrin Hulsey
- Department of Biological Sciences, University of Konstanz, Konstanz, 78457, Germany
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Hulsey CD, Bell KL, García-de-León FJ, Nice CC, Meyer A. Do relaxed selection and habitat temperature facilitate biased mitogenomic introgression in a narrowly endemic fish? Ecol Evol 2016; 6:3684-3698. [PMID: 27186367 PMCID: PMC4853310 DOI: 10.1002/ece3.2121] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/14/2016] [Accepted: 03/21/2016] [Indexed: 12/19/2022] Open
Abstract
Introgression might be exceptionally common during the evolution of narrowly endemic species. For instance, in the springs of the small and isolated Cuatro Ciénegas Valley, the mitogenome of the cichlid fish Herichthys cyanoguttatus could be rapidly introgressing into populations of the trophically polymorphic H. minckleyi. We used a combination of genetic and environmental data to examine the factors associated with this mitochondrial introgression. A reduced representation library of over 6220 single nucleotide polymorphisms (SNPs) from the nuclear genome showed that mitochondrial introgression into H. minckleyi is biased relative to the amount of nuclear introgression. SNP assignment probabilities also indicated that cichlids with more hybrid ancestry are not more commonly female providing no support for asymmetric backcrossing or hybrid‐induced sex‐ratio distortion in generating the bias in mitochondrial introgression. Smaller effective population size in H. minckleyi inferred from the SNPs coupled with sequences of all 13 mitochondrial proteins suggests that relaxed selection on the mitogenome could be facilitating the introgression of “H. cyanoguttatus” haplotypes. Additionally, we showed that springs with colder temperatures had greater amounts of mitochondrial introgression from H. cyanoguttatus. Relaxed selection in H. minckleyi coupled with temperature‐related molecular adaptation could be facilitating mitogenomic introgression into H. minckleyi.
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Affiliation(s)
| | - Katherine L Bell
- Department of Biology Texas State University, San Marcos 601 University Drive 78666 San Marcos Texas
| | - Francisco J García-de-León
- Laboratorio de Genética para la Conservación Centro de Investigaciones Biológicas del Noroeste PO Box 128 La Paz B.C.S. Mexico
| | - Chris C Nice
- Department of Biology Texas State University, San Marcos 601 University Drive 78666 San Marcos Texas
| | - Axel Meyer
- Department of Biology University of Konstanz Universitätstraße 10 78457 Konstanz Germany
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Genner MJ, Ngatunga BP, Mzighani S, Smith A, Turner GF. Geographical ancestry of Lake Malawi's cichlid fish diversity. Biol Lett 2016; 11:20150232. [PMID: 26063752 DOI: 10.1098/rsbl.2015.0232] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The Lake Malawi haplochromine cichlid flock is one of the largest vertebrate adaptive radiations. The geographical source of the radiation has been assumed to be rivers to the south and east of Lake Malawi, where extant representatives of the flock are now present. Here, we provide mitochondrial DNA evidence suggesting the sister taxon to the Lake Malawi radiation is within the Great Ruaha river in Tanzania, north of Lake Malawi. Estimates of the time of divergence between the Lake Malawi flock and this riverine sister taxon range from 2.13 to 6.76 Ma, prior to origins of the current radiation 1.20-4.06 Ma. These results are congruent with evaluations of 2-3.75 Ma fossil material that suggest past faunal connections between Lake Malawi and the Ruaha. We propose that ancestors of the Malawi radiation became isolated within the catchment during Pliocene rifting that formed both Lake Malawi and the Kipengere/Livingstone mountain range, before colonizing rivers to the south and east of the lake region and radiating within the lake basin. Identification of this sister taxon allows tests of whether standing genetic diversity has predisposed Lake Malawi cichlids to rapid speciation and adaptive radiation.
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Affiliation(s)
- Martin J Genner
- School of Biological Sciences, University of Bristol, Life Sciences Building, Bristol BS81TQ, UK
| | - Benjamin P Ngatunga
- Tanzania Fisheries Research Institute (TAFIRI), PO Box 9750, Dar-es-Salaam, Tanzania
| | - Semvua Mzighani
- Tanzania Fisheries Research Institute (TAFIRI), PO Box 9750, Dar-es-Salaam, Tanzania
| | - Alan Smith
- School of Biological, Biomedical and Environmental Science, University of Hull, Hull HU67RX, UK
| | - George F Turner
- School of Biological Sciences, Bangor University, Bangor, Gwynedd LL572UW, UK
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Yuan XL, Zhang ZF, Liu XM, Du YM, Zhang P, Hou XD. Mitochondrial genome analysis of Mylochromis lateristriga. MITOCHONDRIAL DNA PART B-RESOURCES 2016; 1:43-44. [PMID: 33473401 PMCID: PMC7799834 DOI: 10.1080/23802359.2015.1137814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Mylochromis lateristriga is a species of cichlid endemic and prefers sheltered bays or vegetated substrates. In this study, the mitochondrial genome of M. lateristriga was completed using PCR and Sanger sequencing method. The genome is a circular molecule with the length of 16 576 bp and contains 13 protein-coding genes (PCGs), 22 transfer tRNA genes and two ribosomal RNA genes. Except COX1 gene, the other protein-coding genes are started with ATG. The average A + T content is 54.1%. Gene overlaps have been found at four junctions and have involved a total of 26 bp. Compared with other cichlid species, the genome exhibits high similarity in both the genome size and the genome structure. ML phylogenetic analysis was implemented with other 20 related species to verity the genetic relationship of M. lateristriga.
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Affiliation(s)
- Xiao-Long Yuan
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Zhong-Feng Zhang
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Xin-Min Liu
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Yong-Mei Du
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Peng Zhang
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Xiao-Dong Hou
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao, China
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Machado DJ, Lyra ML, Grant T. Mitogenome assembly from genomic multiplex libraries: comparison of strategies and novel mitogenomes for five species of frogs. Mol Ecol Resour 2015; 16:686-93. [PMID: 26607054 DOI: 10.1111/1755-0998.12492] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 11/09/2015] [Accepted: 11/17/2015] [Indexed: 11/27/2022]
Abstract
Next-generation sequencing continues to revolutionize biodiversity studies by generating unprecedented amounts of DNA sequence data for comparative genomic analysis. However, these data are produced as millions or billions of short reads of variable quality that cannot be directly applied in comparative analyses, creating a demand for methods to facilitate assembly. We optimized an in silico strategy to efficiently reconstruct high-quality mitochondrial genomes directly from genomic reads. We tested this strategy using sequences from five species of frogs: Hylodes meridionalis (Hylodidae), Hyloxalus yasuni (Dendrobatidae), Pristimantis fenestratus (Craugastoridae), and Melanophryniscus simplex and Rhinella sp. (Bufonidae). These are the first mitogenomes published for these species, the genera Hylodes, Hyloxalus, Pristimantis, Melanophryniscus and Rhinella, and the families Craugastoridae and Hylodidae. Sequences were generated using only half of one lane of a standard Illumina HiqSeq 2000 flow cell, resulting in fewer than eight million reads. We analysed the reads of Hylodes meridionalis using three different assembly strategies: (1) reference-based (using bowtie2); (2) de novo (using abyss, soapdenovo2 and velvet); and (3) baiting and iterative mapping (using mira and mitobim). Mitogenomes were assembled exclusively with strategy 3, which we employed to assemble the remaining mitogenomes. Annotations were performed with mitos and confirmed by comparison with published amphibian mitochondria. In most cases, we recovered all 13 coding genes, 22 tRNAs, and two ribosomal subunit genes, with minor gene rearrangements. Our results show that few raw reads can be sufficient to generate high-quality scaffolds, making any Illumina machine run using genomic multiplex libraries a potential source of data for organelle assemblies as by-catch.
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Affiliation(s)
- D J Machado
- Department of Zoology, Institute of Biosciences, University of São Paulo, R. do Matão 101, São Paulo, SP, CEP 05508-090, Brazil
| | - M L Lyra
- Department of Zoology, Institute of Biosciences, São Paulo State University, Campus Rio Claro, Av. 24-A 1515, Rio Claro, SP, CEP 13506-900, Brazil
| | - T Grant
- Department of Zoology, Institute of Biosciences, University of São Paulo, R. do Matão 101, São Paulo, SP, CEP 05508-090, Brazil
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Mu XD, Liu C, Wang XJ, Liu Y, Hu YC, Luo JR. Complete mitochondrial genome of Zebra tilapia, Tilapia buttikoferi. Mitochondrial DNA A DNA Mapp Seq Anal 2014; 27:44-5. [PMID: 24438265 DOI: 10.3109/19401736.2013.869687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We determined the complete mitochondrial genome of Tilapia buttikoferi, which was 16,577 bp in length with an A + T content of 53.0%, containing 13 protein-coding genes, 2 rRNAs, 22 tRNAs and a complete control region. The gene arrangement was similar to that of typical fishes. The total base composition of the mitogenome was 25.6% T, 30.8% C, 27.4% A and 16.2% G. Of the 13 protein-coding genes, 12 genes start with an ATG codon, except for COX1 with GTG. Seven (ND1, ND2, COX1, ATPase8, ATPase6, ND4L and ND6) used TAA or AGA as the termination codon, whereas six (COX2, COX3, ND3, ND4, ND5 and cyt b) had incomplete stop codon T. Its control region was atypical in being short at 861 bp, and contained TACAT motif and one microsatellite-like region (TA)7. This mitogenome sequence data may be useful for phylogenetic and systematic analyses within the family Cichlaidae.
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Affiliation(s)
- Xi-Dong Mu
- a Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation , Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Ministry of Agriculture , Guangzhou , China
| | - Chao Liu
- a Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation , Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Ministry of Agriculture , Guangzhou , China
| | - Xue-Jie Wang
- a Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation , Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Ministry of Agriculture , Guangzhou , China
| | - Yi Liu
- a Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation , Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Ministry of Agriculture , Guangzhou , China
| | - Yin-Chang Hu
- a Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation , Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Ministry of Agriculture , Guangzhou , China
| | - Jian-Ren Luo
- a Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation , Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Ministry of Agriculture , Guangzhou , China
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Hulsey CD, García-de-León FJ. Introgressive hybridization in a trophically polymorphic cichlid. Ecol Evol 2013; 3:4536-47. [PMID: 24340193 PMCID: PMC3856752 DOI: 10.1002/ece3.841] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 09/10/2013] [Accepted: 09/17/2013] [Indexed: 11/09/2022] Open
Abstract
Trophically polymorphic species could represent lineages that are rapidly diverging along an ecological axis or could phenotypically mark the collapse of species through introgressive hybridization. We investigated patterns of introgression between the trophically polymorphic cichlid fish Herichthys minckleyi and its relative H. cyanoguttatus using a combination of population genetics and species tree analyses. We first examined the distribution of mitochondrial haplotypes within the alternative H. minckleyi pharyngeal jaw morphotypes that are endemic to the small desert valley of Cuatro Ciénegas. We recovered two clusters of mitochondrial haplotypes. The first contained a number of slightly differentiated cytochrome b (cytb) haplotypes that showed some phylogeographic signal and were present in both jaw morphotypes. The other haplotype was monomorphic, highly differentiated from the other cluster, present in equal frequencies in the morphotypes, and identical to H. cyanoguttatus haplotypes found outside Cuatro Ciénegas. Then, we investigated whether H. minckleyi individuals with the H. cyanoguttatus cytb were more evolutionarily similar to H. cyanoguttatus or other H. minckleyi using a species tree analysis of 84 nuclear loci. Both H. minckleyi pharyngeal morphotypes, regardless of their cytb haplotype, were quite distinct from H. cyanoguttatus. However, hybridization could be blurring subdivision within H. minckleyi as the alternative jaw morphotypes were not genetically distinct from one another. Accounting for introgression from H. cyanoguttatus will be essential to understand the evolution of the trophically polymorphic cichlid H. minckleyi.
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Affiliation(s)
- C Darrin Hulsey
- Department of Ecology and Evolutionary Biology, University of Tennessee 569 Dabney Hall, Knoxville, Tennessee, 37996
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Hulsey CD, Roberts RJ, Loh YHE, Rupp MF, Streelman JT. Lake Malawi cichlid evolution along a benthic/limnetic axis. Ecol Evol 2013; 3:2262-72. [PMID: 23919168 PMCID: PMC3728963 DOI: 10.1002/ece3.633] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 05/08/2013] [Accepted: 05/09/2013] [Indexed: 11/12/2022] Open
Abstract
Divergence along a benthic to limnetic habitat axis is ubiquitous in aquatic systems. However, this type of habitat divergence has largely been examined in low diversity, high latitude lake systems. In this study, we examined the importance of benthic and limnetic divergence within the incredibly species-rich radiation of Lake Malawi cichlid fishes. Using novel phylogenetic reconstructions, we provided a series of hypotheses regarding the evolutionary relationships among 24 benthic and limnetic species that suggests divergence along this axis has occurred multiple times within Lake Malawi cichlids. Because pectoral fin morphology is often associated with divergence along this habitat axis in other fish groups, we investigated divergence in pectoral fin muscles in these benthic and limnetic cichlid species. We showed that the eight pectoral fin muscles and fin area generally tended to evolve in a tightly correlated manner in the Lake Malawi cichlids. Additionally, we found that larger pectoral fin muscles are strongly associated with the independent evolution of the benthic feeding habit across this group of fish. Evolutionary specialization along a benthic/limnetic axis has occurred multiple times within this tropical lake radiation and has produced repeated convergent matching between exploitation of water column habitats and locomotory morphology.
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Affiliation(s)
- C D Hulsey
- Department of Ecology and Evolutionary Biology, University of Tennessee Knoxville, Tennessee, 37996
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