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Sierra NC, Gold DA. The evolution of cnidarian stinging cells supports a Precambrian radiation of animal predators. Evol Dev 2024; 26:e12469. [PMID: 38236185 DOI: 10.1111/ede.12469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 11/22/2023] [Accepted: 12/31/2023] [Indexed: 01/19/2024]
Abstract
Cnidarians-the phylum including sea anemones, corals, jellyfish, and hydroids-are one of the oldest groups of predatory animals. Nearly all cnidarians are carnivores that use stinging cells called cnidocytes to ensnare and/or envenom their prey. However, there is considerable diversity in cnidocyte form and function. Tracing the evolutionary history of cnidocytes may therefore provide a proxy for early animal feeding strategies. In this study, we generated a time-calibrated molecular clock of cnidarians and performed ancestral state reconstruction on 12 cnidocyte types to test the hypothesis that the original cnidocyte was involved in prey capture. We conclude that the first cnidarians had only the simplest and least specialized cnidocyte type (the isorhiza) which was just as likely to be used for adhesion and/or defense as the capture of prey. A rapid diversification of specialized cnidocytes occurred through the Ediacaran (~654-574 million years ago), with major subgroups developing unique sets of cnidocytes to match their distinct feeding styles. These results are robust to changes in the molecular clock model, and are consistent with growing evidence for an Ediacaran diversification of animals. Our work also provides insight into the evolution of this complex cell type, suggesting that convergence of forms is rare, with the mastigophore being an interesting counterexample.
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Affiliation(s)
- Noémie C Sierra
- Department of Earth and Planetary Sciences, University of California, Davis, Davis, California, USA
- Integrative Genetics and Genomics, University of California, Davis, Davis, California, USA
| | - David A Gold
- Department of Earth and Planetary Sciences, University of California, Davis, Davis, California, USA
- Integrative Genetics and Genomics, University of California, Davis, Davis, California, USA
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Zancolli G, Casewell NR. Venom Systems as Models for Studying the Origin and Regulation of Evolutionary Novelties. Mol Biol Evol 2020; 37:2777-2790. [DOI: 10.1093/molbev/msaa133] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Abstract
A central goal in biology is to determine the ways in which evolution repeats itself. One of the most remarkable examples in nature of convergent evolutionary novelty is animal venom. Across diverse animal phyla, various specialized organs and anatomical structures have evolved from disparate developmental tissues to perform the same function, that is, produce and deliver a cocktail of potent molecules to subdue prey or predators. Venomous organisms therefore offer unique opportunities to investigate the evolutionary processes of convergence of key adaptive traits, and the molecular mechanisms underlying the emergence of novel genes, cells, and tissues. Indeed, some venomous species have already proven to be highly amenable as models for developmental studies, and recent work with venom gland organoids provides manipulatable systems for directly testing important evolutionary questions. Here, we provide a synthesis of the current knowledge that could serve as a starting point for the establishment of venom systems as new models for evolutionary and molecular biology. In particular, we highlight the potential of various venomous species for the study of cell differentiation and cell identity, and the regulatory dynamics of rapidly evolving, highly expressed, tissue-specific, gene paralogs. We hope that this review will encourage researchers to look beyond traditional study organisms and consider venom systems as useful tools to explore evolutionary novelties.
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Affiliation(s)
- Giulia Zancolli
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Nicholas R Casewell
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Apprill A. The Role of Symbioses in the Adaptation and Stress Responses of Marine Organisms. ANNUAL REVIEW OF MARINE SCIENCE 2020; 12:291-314. [PMID: 31283425 DOI: 10.1146/annurev-marine-010419-010641] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Ocean ecosystems are experiencing unprecedented rates of climate and anthropogenic change, which can often initiate stress in marine organisms. Symbioses, or associations between different organisms, are plentiful in the ocean and could play a significant role in facilitating organismal adaptations to stressful ocean conditions. This article reviews current knowledge about the role of symbiosis in marine organismal acclimation and adaptation. It discusses stress and adaptations in symbioses from coral reef ecosystems, which are among the most affected environments in the ocean, including the relationships between corals and microalgae, corals and bacteria, anemones and clownfish, and cleaner fish and client fish. Despite the importance of this subject, knowledge of how marine organisms adapt to stress is still limited, and there are vast opportunities for research and technological development in this area. Attention to this subject will enhance our understanding of the capacity of symbioses to alleviate organismal stress in the oceans.
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Affiliation(s)
- Amy Apprill
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA;
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Panchin AY, Aleoshin VV, Panchin YV. From tumors to species: a SCANDAL hypothesis. Biol Direct 2019; 14:3. [PMID: 30674330 PMCID: PMC6343361 DOI: 10.1186/s13062-019-0233-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 01/13/2019] [Indexed: 11/27/2022] Open
Abstract
ᅟ Some tumor cells can evolve into transmissible parasites. Notable examples include the Tasmanian devil facial tumor disease, the canine transmissible venereal tumor and transmissible cancers of mollusks. We present a hypothesis that such transmissible tumors existed in the past and that some modern animal taxa are descendants of these tumors. We expect potential candidates for SCANDALs (speciated by cancer development animals) to be simplified relatives of more complex metazoans and have genomic alterations typical for cancer progression (such as deletions of universal apoptosis genes). We considered several taxa of simplified animals for our hypothesis: dicyemida, orthonectida, myxosporea and trichoplax. Based on genomic analysis we conclude that Myxosporea appear to be the most suitable candidates for a tumor ancestry. They are simplified parasitic cnidarians that universally lack major genes implicated in cancer progression including all genes with Caspase and BCL2 domains as well as any p53 and apoptotic protease activating factor – 1 (Apaf-1) homologs, suggesting the disruption of main apoptotic pathways in their early evolutionary history. Further comparative genomics and single-cell transcriptomic studies may be helpful to test our hypothesis of speciation via a cancerous stage. Reviewers This article was reviewed by Eugene Koonin, Mikhail Gelfand and Gregory M Woods. Electronic supplementary material The online version of this article (10.1186/s13062-019-0233-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- A Y Panchin
- Institute for Information Transmission Problems, Bolshoy Karetniy Pereulok 19/1, Moscow, Russian Federation, 127051.
| | - V V Aleoshin
- Institute for Information Transmission Problems, Bolshoy Karetniy Pereulok 19/1, Moscow, Russian Federation, 127051.,A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, Russia
| | - Y V Panchin
- Institute for Information Transmission Problems, Bolshoy Karetniy Pereulok 19/1, Moscow, Russian Federation, 127051.,A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, Russia
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Ben-David J, Atkinson SD, Pollak Y, Yossifon G, Shavit U, Bartholomew JL, Lotan T. Myxozoan polar tubules display structural and functional variation. Parasit Vectors 2016; 9:549. [PMID: 27741948 PMCID: PMC5064783 DOI: 10.1186/s13071-016-1819-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 09/28/2016] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Myxozoa is a speciose group of endoparasitic cnidarians that can cause severe ecological and economic effects. Although highly reduced compared to free-living cnidarians, myxozoans have retained the phylum-defining stinging organelles, known as cnidae or polar capsules, which are essential to initiating host infection. To explore the adaptations of myxozoan polar capsules, we compared the structure, firing process and content release mechanism of polar tubules in myxospores of three Myxobolus species including M. cerebralis, the causative agent of whirling disease. RESULTS We found novel functions and morphologies in myxozoan polar tubules. High-speed video analysis of the firing process of capsules from the three Myxobolus species showed that all polar tubules rapidly extended and then contracted, an elasticity phenomenon that is unknown in free-living cnidarians. Interestingly, the duration of the tubule release differed among the three species by more than two orders of magnitude, ranging from 0.35 to 10 s. By dye-labeling the polar capsules prior to firing, we discovered that two of the species could release their entire capsule content, a delivery process not previously known from myxozoans. Having the role of content delivery and not simply anchoring suggests that cytotoxic or proteolytic compounds may be present in the capsule. Moreover, while free-living cnidarians inject most of the toxic content through the distal tip of the tubule, our video and ultrastructure analyses of the myxozoan tubules revealed patterns of double spirals of nodules and pores along parts of the tubules, and showed that the distal tip of the tubules was sealed. This helical pattern and distribution of openings may minimize the tubule mechanical weakness and improve resistance to the stress impose by firing. The finding that myxozoan tubule characteristics are very different from those of free-living cnidarians is suggestive of their adaptation to parasitic life. CONCLUSIONS These findings show that myxozoan polar tubules have more functions than previously assumed, and provide insight into their evolution from free-living ancestors.
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Affiliation(s)
- Jonathan Ben-David
- Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, 31905, Israel
| | - Stephen D Atkinson
- Department of Microbiology, Oregon State University, Nash Hall 226, Corvallis, OR, 97331, USA
| | - Yulia Pollak
- Electron Microscopy Unit, Faculty of Natural Sciences, University of Haifa, Haifa, 31905, Israel
| | - Gilad Yossifon
- Faculty of Mechanical Engineering, Technion, Haifa, 32000, Israel
| | - Uri Shavit
- Faculty of Civil and Environmental Engineering, Technion, Haifa, 32000, Israel
| | - Jerri L Bartholomew
- Department of Microbiology, Oregon State University, Nash Hall 226, Corvallis, OR, 97331, USA
| | - Tamar Lotan
- Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, 31905, Israel.
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Foox J, Siddall ME. The Road To Cnidaria: History of Phylogeny of the Myxozoa. J Parasitol 2015; 101:269-74. [PMID: 25621522 DOI: 10.1645/14-671.1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Myxozoans are a clade of highly derived cnidarians. The phylogenetic identity of these extremely simplified parasites of aquatic vertebrates and invertebrates had long been uncertain, with all early classifications designating Myxozoa as protists. Though suggestions were frequently made that the infective spores of these parasites are multicellular and possibly of cnidarian origin, it would take a phylogenetic analysis of ultrastructural developmental characters in combination with rRNA gene sequences to verify the Myxozoa as secondarily reduced cnidarians, sister to the polypoidozoan parasite Polypodium hydriforme . While a series of subsequent molecular studies suggested hypotheses of Myxozoa as basal bilaterians, triploblasts, or even nematodes, phylogenomic analyses with improved taxon sampling corroborated the landmark paper that verified the cnidarian nature of this group. This review of the body of phylogenetic work on Myxozoa aims to clarify historical progress and current knowledge, as well as to emphasize the opportune position that myxozoan biologists now are in, to address fundamental questions of cell biology of these parasites as well as the evolution of animal life.
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Affiliation(s)
- Jonathan Foox
- Richard Gilder Graduate School, American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024
| | - Mark E Siddall
- Richard Gilder Graduate School, American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024
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Gorelick R. Do Micrognathozoa have micro-genomes? Biol J Linn Soc Lond 2014. [DOI: 10.1111/bij.12284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Root Gorelick
- Department of Biology; School of Mathematics & Statistics; Institute of Interdisciplinary Studies; Carleton University; 1125 Colonel By Ottawa ON Canada K1S 5B6
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Babonis LS, Martindale MQ. Old cell, new trick? Cnidocytes as a model for the evolution of novelty. Integr Comp Biol 2014; 54:714-22. [PMID: 24771087 DOI: 10.1093/icb/icu027] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Understanding how new cell types arise is critical for understanding the evolution of organismal complexity. Questions of this nature, however, can be difficult to answer due to the challenge associated with defining the identity of a truly novel cell. Cnidarians (anemones, jellies, and their allies) provide a unique opportunity to investigate the molecular regulation and development of cell-novelty because they possess a cell that is unique to the cnidarian lineage and that also has a very well-characterized phenotype: the cnidocyte (stinging cell). Because cnidocytes are thought to differentiate from the cell lineage that also gives rise to neurons, cnidocytes can be expected to express many of the same genes expressed in their neural "sister" cells. Conversely, only cnidocytes posses a cnidocyst (the explosive organelle that gives cnidocytes their sting); therefore, those genes or gene-regulatory relationships required for the development of the cnidocyst can be expected to be expressed uniquely (or in unique combination) in cnidocytes. This system provides an important opportunity to: (1) construct the gene-regulatory network (GRN) underlying the differentiation of cnidocytes, (2) assess the relative contributions of both conserved and derived genes in the cnidocyte GRN, and (3) test hypotheses about the role of novel regulatory relationships in the generation of novel cell types. In this review, we summarize common challenges to studying the evolution of novelty, introduce the utility of cnidocyte differentiation in the model cnidarian, Nematostella vectensis, as a means of overcoming these challenges, and describe an experimental approach that leverages comparative tissue-specific transcriptomics to generate hypotheses about the GRNs underlying the acquisition of the cnidocyte identity.
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Affiliation(s)
- Leslie S Babonis
- Whitney Laboratory for Marine Bioscience, University of Florida, 9505 N Oceanshore Blvd, St. Augustine, FL 32080, USA
| | - Mark Q Martindale
- Whitney Laboratory for Marine Bioscience, University of Florida, 9505 N Oceanshore Blvd, St. Augustine, FL 32080, USA
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Ye LT, Li WX, Wu SG, Wang GT. Supplementary studies on Henneguya doneci Schulman, 1962 (Myxozoa: Myxosporea) infecting the gill filaments of Carassius auratus gibelio (Bloch) in China: histologic, ultrastructural, and molecular data. Parasitol Res 2011; 110:1509-16. [DOI: 10.1007/s00436-011-2655-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Accepted: 09/08/2011] [Indexed: 12/01/2022]
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Holland JW, Okamura B, Hartikainen H, Secombes CJ. A novel minicollagen gene links cnidarians and myxozoans. Proc Biol Sci 2010; 278:546-53. [PMID: 20810433 DOI: 10.1098/rspb.2010.1301] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Myxozoans are enigmatic endoparasitic organisms sharing morphological features with bilateria, protists and cnidarians. This, coupled with their highly divergent gene sequences, has greatly obscured their phylogenetic affinities. Here we report the sequencing and characterization of a minicollagen homologue (designated Tb-Ncol-1) in the myxozoan Tetracapsuloides bryosalmonae. Minicollagens are phylum-specific genes encoding cnidarian nematocyst proteins. Sequence analysis revealed a cysteine-rich domain (CRD) architecture and genomic organization similar to group 1 minicollagens. Homology modelling predicted similar three-dimensional structures to Hydra CRDs despite deviations from the canonical pattern of group 1 minicollagens. The discovery of this minicollagen gene strongly supports myxozoans as cnidarians that have radiated as endoparasites of freshwater, marine and terrestrial hosts. It also reveals novel protein sequence variation of relevance to understanding the evolution of nematocyst complexity, and indicates a molecular/morphological link between myxozoan polar capsules and cnidarian nematocysts. Our study is the first to illustrate the power of using genes related to a taxon-specific novelty for phylogenetic inference within the Metazoa, and it exemplifies how the evolutionary relationships of other metazoans characterized by extreme sequence divergence could be similarly resolved.
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Affiliation(s)
- Jason W Holland
- Scottish Fish Immunology Research Centre, Aberdeen University, , Aberdeen AB24 2TZ, UK.
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Origins of neurogenesis, a cnidarian view. Dev Biol 2009; 332:2-24. [PMID: 19465018 DOI: 10.1016/j.ydbio.2009.05.563] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2009] [Revised: 05/14/2009] [Accepted: 05/16/2009] [Indexed: 11/22/2022]
Abstract
New perspectives on the origin of neurogenesis emerged with the identification of genes encoding post-synaptic proteins as well as many "neurogenic" regulators as the NK, Six, Pax, bHLH proteins in the Demosponge genome, a species that might differentiate sensory cells but no neurons. However, poriferans seem to miss some key regulators of the neurogenic circuitry as the Hox/paraHox and Otx-like gene families. Moreover as a general feature, many gene families encoding evolutionarily-conserved signaling proteins and transcription factors were submitted to a wave of gene duplication in the last common eumetazoan ancestor, after Porifera divergence. In contrast gene duplications in the last common bilaterian ancestor, Urbilateria, are limited, except for the bHLH Atonal-class. Hence Cnidaria share with Bilateria a large number of genetic tools. The expression and functional analyses currently available suggest a neurogenic function for numerous orthologs in developing or adult cnidarians where neurogenesis takes place continuously. As an example, in the Hydra polyp, the Clytia medusa and the Acropora coral, the Gsx/cnox2/Anthox-2 ParaHox gene likely supports neurogenesis. Also neurons and nematocytes (mechanosensory cells) share in hydrozoans a common stem cell and several regulatory genes indicating that they can be considered as sister cells. Performed in anthozoan and medusozoan species, these studies should tell us more about the way(s) evolution hazards achieved the transition from epithelial to neuronal cell fate, and about the robustness of the genetic circuitry that allowed neuromuscular transmission to arise and be maintained across evolution.
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Abstract
Cnidae are secreted by the Golgi apparatus of all cnidarians and only cnidarians. Of the three categories of cnidae (also called cnidocysts), nematocysts occur in all cnidarians, and are the means by which cnidarians defend themselves and obtain prey; spirocysts and ptychocysts are restricted to a minority of major taxa. A cnida discharges by eversion of its tubule; venom may be associated with the tubule of a nematocyst. About 30 major morphological types of nematocysts are recognized, but no single nomenclature for them is accepted. Function seems not to correlate tightly with morphology--nematocysts of at least some types are used both offensively and defensively. Similarly, it is not clear if morphology correlates with toxicity. Some types of nematocysts are taxonomically diagnostic whereas others are widespread. Nonetheless, an inventory of types of cnidae (the cnidom), with their distribution and size, is an essential component of most taxonomic descriptions. Complicating the taxonomic value of cnidae are the facts that not all members of a species may have the same types of cnidae, even at the same life-cycle stage, and size of nematocysts of a species may vary geographically and with size of individual. The diversity of nematocysts is so great and the features within each major type are so variable that homologies have not been determined. Nematocyst complement, morphology, and size likely reflect both phylogeny and biology; the feedback between the two may confound analysis. Although cnidae are valuable in taxonomy of at least some groups, more understanding of the forces that affect them is needed for their systematic and phylogenetic value to be understood and their potential as indicators of evolution to be realized.
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Affiliation(s)
- Daphne Gail Fautin
- Department of Ecology and Evolutionary Biology, and Natural History Museum and Biodiversity Research Center, University of Kansas, 1200 Sunnyside Drive, Lawrence, KS 66045, USA.
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David CN, Özbek S, Adamczyk P, Meier S, Pauly B, Chapman J, Hwang JS, Gojobori T, Holstein TW. Evolution of complex structures: minicollagens shape the cnidarian nematocyst. Trends Genet 2008; 24:431-8. [DOI: 10.1016/j.tig.2008.07.001] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Revised: 06/27/2008] [Accepted: 07/04/2008] [Indexed: 01/03/2023]
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Okamura B, Canning EU. Orphan worms and homeless parasites enhance bilaterian diversity. Trends Ecol Evol 2003. [DOI: 10.1016/j.tree.2003.09.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Phylogenetic Analysis of Complete Small Subunit Ribosomal RNA Coding Region of Myxidium lieberkuehni: Evidence that Myxozoa are Metazoa and Related to the Bilateria. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s0003-9365(96)80002-9] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Skala Z, Zrzavy J. PHYLOGENETIC RETICULATIONS AND CLADISTICS: DISCUSSION OF METHODOLOGICAL CONCEPTS. Cladistics 1994. [DOI: 10.1111/j.1096-0031.1994.tb00180.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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SHOSTAK STANLEY. Symbiogenetic origins of Cnidaria: Updating an hypothesis. INVERTEBR REPROD DEV 1993. [DOI: 10.1080/07924259.1993.9672310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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