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Souza LS, Solowiej-Wedderburn J, Bonforti A, Libby E. Modeling endosymbioses: Insights and hypotheses from theoretical approaches. PLoS Biol 2024; 22:e3002583. [PMID: 38598454 PMCID: PMC11006130 DOI: 10.1371/journal.pbio.3002583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024] Open
Abstract
Endosymbiotic relationships are pervasive across diverse taxa of life, offering key avenues for eco-evolutionary dynamics. Although a variety of experimental and empirical frameworks have shed light on critical aspects of endosymbiosis, theoretical frameworks (mathematical models) are especially well-suited for certain tasks. Mathematical models can integrate multiple factors to determine the net outcome of endosymbiotic relationships, identify broad patterns that connect endosymbioses with other systems, simplify biological complexity, generate hypotheses for underlying mechanisms, evaluate different hypotheses, identify constraints that limit certain biological interactions, and open new lines of inquiry. This Essay highlights the utility of mathematical models in endosymbiosis research, particularly in generating relevant hypotheses. Despite their limitations, mathematical models can be used to address known unknowns and discover unknown unknowns.
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Affiliation(s)
- Lucas Santana Souza
- Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden
- Integrated Science Lab, Umeå University, Umeå, Sweden
| | - Josephine Solowiej-Wedderburn
- Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden
- Integrated Science Lab, Umeå University, Umeå, Sweden
| | - Adriano Bonforti
- Integrated Science Lab, Umeå University, Umeå, Sweden
- Department of Ecology and Environmental Science, Umeå University, Umeå, Sweden
- Umeå Marine Sciences Centre, Umeå University, Norrbyn, Sweden
| | - Eric Libby
- Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden
- Integrated Science Lab, Umeå University, Umeå, Sweden
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2
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Cornwallis CK, van 't Padje A, Ellers J, Klein M, Jackson R, Kiers ET, West SA, Henry LM. Symbioses shape feeding niches and diversification across insects. Nat Ecol Evol 2023; 7:1022-1044. [PMID: 37202501 PMCID: PMC10333129 DOI: 10.1038/s41559-023-02058-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 03/15/2023] [Indexed: 05/20/2023]
Abstract
For over 300 million years, insects have relied on symbiotic microbes for nutrition and defence. However, it is unclear whether specific ecological conditions have repeatedly favoured the evolution of symbioses, and how this has influenced insect diversification. Here, using data on 1,850 microbe-insect symbioses across 402 insect families, we found that symbionts have allowed insects to specialize on a range of nutrient-imbalanced diets, including phloem, blood and wood. Across diets, the only limiting nutrient consistently associated with the evolution of obligate symbiosis was B vitamins. The shift to new diets, facilitated by symbionts, had mixed consequences for insect diversification. In some cases, such as herbivory, it resulted in spectacular species proliferation. In other niches, such as strict blood feeding, diversification has been severely constrained. Symbioses therefore appear to solve widespread nutrient deficiencies for insects, but the consequences for insect diversification depend on the feeding niche that is invaded.
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Affiliation(s)
| | - Anouk van 't Padje
- Amsterdam Institute for Life and Environment, section Ecology and Evolution, Vrije Universiteit, Amsterdam, the Netherlands
- Laboratory of Genetics, Wageningen University and Research, Wageningen, the Netherlands
| | - Jacintha Ellers
- Amsterdam Institute for Life and Environment, section Ecology and Evolution, Vrije Universiteit, Amsterdam, the Netherlands
| | - Malin Klein
- Amsterdam Institute for Life and Environment, section Ecology and Evolution, Vrije Universiteit, Amsterdam, the Netherlands
| | - Raphaella Jackson
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK
| | - E Toby Kiers
- Amsterdam Institute for Life and Environment, section Ecology and Evolution, Vrije Universiteit, Amsterdam, the Netherlands
| | - Stuart A West
- Department of Biology, University of Oxford, Oxford, UK
| | - Lee M Henry
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK.
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3
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Clejan I, Congleton CD, Lerch BA. The emergence of group fitness. Evolution 2022; 76:1689-1705. [PMID: 35767747 DOI: 10.1111/evo.14549] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 06/06/2022] [Accepted: 06/13/2022] [Indexed: 01/22/2023]
Abstract
Whether and how selection can act on collectives rather than single entities has been a tumultuous issue in evolutionary biology for decades. Despite examples of multilevel selection, a simple framework is needed that makes explicit the constraints that lead to the emergence of a "group fitness function." We use evolutionary game theory to show that two constraints are sufficient for the emergence of a well-defined group fitness, which could even apply to multispecies groups. First, different parts of the group contribute to one another's growth via resources produced proportionally to the density of each resource producer (not the density of the population receiving benefits). Second, invading groups do not share these resources with resident groups. Jointly, these two constraints lead to the "entanglement" of invading individuals' outcomes such that individual fitness can no longer be defined and group fitness predicts evolutionary dynamics through the emergence of a higher level evolutionary individual. Group fitness is an emergent property, irreducible to the fitness of the group's parts and exhibiting downward causality on the parts. By formalizing group fitness as a model for evolutionary transitions in individuality, these results open up a broad class of models under the multilevel-selection framework.
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Affiliation(s)
| | | | - Brian A Lerch
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599
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4
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Zachar I, Boza G. The Evolution of Microbial Facilitation: Sociogenesis, Symbiogenesis, and Transition in Individuality. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.798045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Metabolic cooperation is widespread, and it seems to be a ubiquitous and easily evolvable interaction in the microbial domain. Mutual metabolic cooperation, like syntrophy, is thought to have a crucial role in stabilizing interactions and communities, for example biofilms. Furthermore, cooperation is expected to feed back positively to the community under higher-level selection. In certain cases, cooperation can lead to a transition in individuality, when freely reproducing, unrelated entities (genes, microbes, etc.) irreversibly integrate to form a new evolutionary unit. The textbook example is endosymbiosis, prevalent among eukaryotes but virtually lacking among prokaryotes. Concerning the ubiquity of syntrophic microbial communities, it is intriguing why evolution has not lead to more transitions in individuality in the microbial domain. We set out to distinguish syntrophy-specific aspects of major transitions, to investigate why a transition in individuality within a syntrophic pair or community is so rare. We review the field of metabolic communities to identify potential evolutionary trajectories that may lead to a transition. Community properties, like joint metabolic capacity, functional profile, guild composition, assembly and interaction patterns are important concepts that may not only persist stably but according to thought-provoking theories, may provide the heritable information at a higher level of selection. We explore these ideas, relating to concepts of multilevel selection and of informational replication, to assess their relevance in the debate whether microbial communities may inherit community-level information or not.
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5
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Macro-symbiosis triggered by a defence-reproduction tradeoff in a social insect. Ecol Modell 2021. [DOI: 10.1016/j.ecolmodel.2021.109780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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6
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Vostinar AE, Skocelas KG, Lalejini A, Zaman L. Symbiosis in Digital Evolution: Past, Present, and Future. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.739047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Symbiosis, the living together of unlike organisms as symbionts, is ubiquitous in the natural world. Symbioses occur within and across all scales of life, from microbial to macro-faunal systems. Further, the interactions between symbionts are multimodal in both strength and type, can span from parasitic to mutualistic within one partnership, and persist over generations. Studying the ecological and evolutionary dynamics of symbiosis in natural or laboratory systems poses a wide range of challenges, including the long time scales at which symbioses evolve de novo, the limited capacity to experimentally control symbiotic interactions, the weak resolution at which we can quantify interactions, and the idiosyncrasies of current model systems. These issues are especially challenging when seeking to understand the ecological effects and evolutionary pressures on and of a symbiosis, such as how a symbiosis may shift between parasitic and mutualistic modes and how that shift impacts the dynamics of the partner population. In digital evolution, populations of computational organisms compete, mutate, and evolve in a virtual environment. Digital evolution features perfect data tracking and allows for experimental manipulations that are impractical or impossible in natural systems. Furthermore, modern computational power allows experimenters to observe thousands of generations of evolution in minutes (as opposed to several months or years), which greatly expands the range of possible studies. As such, digital evolution is poised to become a keystone technique in our methodological repertoire for studying the ecological and evolutionary dynamics of symbioses. Here, we review how digital evolution has been used to study symbiosis, and we propose a series of open questions that digital evolution is well-positioned to answer.
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7
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Huo D, Li H, Cai F, Guo X, Qiao Z, Wang W, Yu G, Li R. Genome Evolution of Filamentous Cyanobacterium Nostoc Species: From Facultative Symbiosis to Free Living. Microorganisms 2021; 9:microorganisms9102015. [PMID: 34683336 PMCID: PMC8539589 DOI: 10.3390/microorganisms9102015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/15/2021] [Accepted: 09/19/2021] [Indexed: 11/16/2022] Open
Abstract
In contrast to obligate bacteria, facultative symbiotic bacteria are mainly characterized by genome enlargement. However, the underlying relationship of this feature with adaptations to various habitats remains unclear. In this study, we used the global genome data of Nostoc strains, including 10 novel genomes sequenced in this study and 26 genomes available from public databases, and analyzed their evolutionary history. The evolutionary boundary of the real clade of Nostoc species was identified and was found to be consistent with the results of polyphasic taxonomy. The initial ancestral species of Nostoc was demonstrated to be consistent with a facultative symbiotic population. Further analyses revealed that Nostoc strains tended to shift from facultative symbiosis to a free-living one, along with an increase in genome sizes during the dispersal of each exterior branch. Intracellular symbiosis was proved to be essentially related to Nostoc evolution, and the adaptation of its members to free-living environments was coupled with a large preference for gene acquisition involved in gene repair and recombination. These findings provided unique evidence of genomic mechanisms by which homologous microbes adapt to distinct life manners and external environments.
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Affiliation(s)
- Da Huo
- CAS Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; (D.H.); (H.L.); (F.C.); (X.G.)
| | - Hua Li
- CAS Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; (D.H.); (H.L.); (F.C.); (X.G.)
- Academy of Plateau Science and Sustainability, Qinghai Normal University, Xining 810016, China
| | - Fangfang Cai
- CAS Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; (D.H.); (H.L.); (F.C.); (X.G.)
- School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Xiaoyu Guo
- CAS Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; (D.H.); (H.L.); (F.C.); (X.G.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhiyi Qiao
- Tianjin Key Laboratory of Aqua-Ecology and Aquaculture, College of Fisheries, Tianjin Agricultural University, Tianjin 300384, China;
| | - Weibo Wang
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China;
| | - Gongliang Yu
- CAS Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; (D.H.); (H.L.); (F.C.); (X.G.)
- Correspondence: (G.Y.); (R.L.); Tel.: +86-027-68780067 (G.Y.); +86-027-68780080 (R.L.); Fax: +86-027-68780123 (G.Y.)
| | - Renhui Li
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou 325000, China
- Correspondence: (G.Y.); (R.L.); Tel.: +86-027-68780067 (G.Y.); +86-027-68780080 (R.L.); Fax: +86-027-68780123 (G.Y.)
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8
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Hayward A, Poulin R, Nakagawa S. A broadscale analysis of host-symbiont cophylogeny reveals the drivers of phylogenetic congruence. Ecol Lett 2021; 24:1681-1696. [PMID: 33987932 DOI: 10.1111/ele.13757] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 02/21/2021] [Accepted: 03/24/2021] [Indexed: 02/06/2023]
Abstract
Symbioses exert substantial biological influence, with great evolutionary and ecological relevance for disease, major evolutionary transitions, and the structure and function of ecological communities. Yet, much remains unknown about the patterns and processes that characterise symbioses. A major unanswered question is the extent to which symbiont phylogenies mirror those of their hosts and if patterns differ for parasites and mutualists. Addressing this question offers fundamental insights into evolutionary processes, such as whether symbionts typically codiverge with their hosts or if diversity is generated via host switches. Here, we perform a meta-analysis of host-symbiont phylogenetic congruence, encompassing 212 host-symbiont cophylogenetic studies that include ~10,000 species. Our analysis supersedes previous qualitative assessments by utilising a quantitative framework. We show that symbiont phylogeny broadly reflects host phylogeny across biodiversity and life-history, demonstrating a general pattern of phylogenetic congruence in host-symbiont interactions. We reveal two key aspects of symbiont life-history that promote closer ties between hosts and symbionts: vertical transmission and mutualism. Mode of symbiosis and mode of transmission are intimately interlinked, but vertical transmission is the dominant factor. Given the pervasiveness of symbioses, these findings provide important insights into the processes responsible for generating and maintaining the Earth's rich biodiversity.
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Affiliation(s)
- Alexander Hayward
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, UK
| | - Robert Poulin
- Department of Zoology, University of Otago, Dunedin, New Zealand
| | - Shinichi Nakagawa
- Evolution & Ecology Research Centre and School of Biological, Earth & Environmental Sciences, University of New South Wales, Sydney, NSW, Australia
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9
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Domesticated and optimized mitochondria: Mitochondrial modifications based on energetic status and cellular stress. Life Sci 2020; 265:118766. [PMID: 33245965 DOI: 10.1016/j.lfs.2020.118766] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/28/2020] [Accepted: 11/11/2020] [Indexed: 12/15/2022]
Abstract
Mitochondria are the main source of energy and play an important role in coupling intracellular and intercellular metabolic cooperation. Cellular stress and energetic status can affect various mitochondrial behaviors, including mitochondrial biogenesis, mitophagy, assembly of respiratory chain supercomplexes and mitochondrial distribution. These modifications usually result in adaptive adjustment of mitochondrial output and resistance to cellular stress. However, when the pro-death signals triggered by excessive damage converge to mitochondria, mitochondrial reserve and functional status can profoundly determine the direction of cell death, and even affect the survival and death of surrounding or distant tissues. In this review, we discuss multiple mitochondrial modifications in eukaryotes based on metabolic status and cellular stress, and review the emerging knowledge about the effects of mitochondrial dysfunction on the fate of cells and surrounding tissues.
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10
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Zeng M, He Y, Du H, Yang J, Wan H. Output Regulation and Function Optimization of Mitochondria in Eukaryotes. Front Cell Dev Biol 2020; 8:598112. [PMID: 33330486 PMCID: PMC7718039 DOI: 10.3389/fcell.2020.598112] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Accepted: 10/26/2020] [Indexed: 12/23/2022] Open
Abstract
The emergence of endosymbiosis between aerobic alpha-proteobacterium and anaerobic eukaryotic cell precursors opened the chapter of eukaryotic evolution. Multiple functions of mitochondria originated from the ancient precursors of mitochondria and underwent remodeling in eukaryotic cells. Due to the dependence on mitochondrial functions, eukaryotic cells need to constantly adjust mitochondrial output based on energy demand and cellular stress. Meanwhile, eukaryotes conduct the metabolic cooperation between different cells through the involvement of mitochondria. Under some conditions, mitochondria might also be transferred to nearby cells to provide a protective mechanism. However, the endosymbiont relationship determines the existence of various types of mitochondrial injury, such as proteotoxic stress, mutational meltdown, oxidative injure, and immune activation caused by released mitochondrial contents. Eukaryotes have a repertoire of mitochondrial optimization processes, including various mitochondrial quality-control proteins, regulation of mitochondrial dynamics and activation of mitochondrial autophagy. When these quality-control processes fail, eukaryotic cells can activate apoptosis to intercept uncontrolled cell death, thereby minimizing the damage to extracellular tissue. In this review, we describe the intracellular and extracellular context-based regulation of mitochondrial output in eukaryotic cells, and introduce new findings on multifaceted quality-control processes to deal with mitochondrial defects.
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Affiliation(s)
- Miaolin Zeng
- College of Basic Medical Science, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yu He
- College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China
| | - Haixia Du
- College of Basic Medical Science, Zhejiang Chinese Medical University, Hangzhou, China
| | - Jiehong Yang
- College of Basic Medical Science, Zhejiang Chinese Medical University, Hangzhou, China
| | - Haitong Wan
- College of Basic Medical Science, Zhejiang Chinese Medical University, Hangzhou, China.,College of Life Science, Zhejiang Chinese Medical University, Hangzhou, China
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11
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Zachar I, Boza G. Endosymbiosis before eukaryotes: mitochondrial establishment in protoeukaryotes. Cell Mol Life Sci 2020; 77:3503-3523. [PMID: 32008087 PMCID: PMC7452879 DOI: 10.1007/s00018-020-03462-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 12/25/2019] [Accepted: 01/14/2020] [Indexed: 02/07/2023]
Abstract
Endosymbiosis and organellogenesis are virtually unknown among prokaryotes. The single presumed example is the endosymbiogenetic origin of mitochondria, which is hidden behind the event horizon of the last eukaryotic common ancestor. While eukaryotes are monophyletic, it is unlikely that during billions of years, there were no other prokaryote-prokaryote endosymbioses as symbiosis is extremely common among prokaryotes, e.g., in biofilms. Therefore, it is even more precarious to draw conclusions about potentially existing (or once existing) prokaryotic endosymbioses based on a single example. It is yet unknown if the bacterial endosymbiont was captured by a prokaryote or by a (proto-)eukaryote, and if the process of internalization was parasitic infection, slow engulfment, or phagocytosis. In this review, we accordingly explore multiple mechanisms and processes that could drive the evolution of unicellular microbial symbioses with a special attention to prokaryote-prokaryote interactions and to the mitochondrion, possibly the single prokaryotic endosymbiosis that turned out to be a major evolutionary transition. We investigate the ecology and evolutionary stability of inter-species microbial interactions based on dependence, physical proximity, cost-benefit budget, and the types of benefits, investments, and controls. We identify challenges that had to be conquered for the mitochondrial host to establish a stable eukaryotic lineage. Any assumption about the initial interaction of the mitochondrial ancestor and its contemporary host based solely on their modern relationship is rather perilous. As a result, we warn against assuming an initial mutually beneficial interaction based on modern mitochondria-host cooperation. This assumption is twice fallacious: (i) endosymbioses are known to evolve from exploitative interactions and (ii) cooperativity does not necessarily lead to stable mutualism. We point out that the lack of evidence so far on the evolution of endosymbiosis from mutual syntrophy supports the idea that mitochondria emerged from an exploitative (parasitic or phagotrophic) interaction rather than from syntrophy.
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Affiliation(s)
- István Zachar
- Evolutionary Systems Research Group, Institute of Evolution, Centre for Ecological Research, Klebelsberg Kunó str. 3., Tihany, 8237, Hungary.
- MTA-ELTE Theoretical Biology and Evolutionary Ecology Research Group, Department of Plant Taxonomy and Ecology, Eötvös Loránd University, Pázmány Péter sétány 1/c, Budapest, 1117, Hungary.
- Center for the Conceptual Foundations of Science, Parmenides Foundation, Kirchplatz 1, 82049, Munich, Germany.
| | - Gergely Boza
- Evolutionary Systems Research Group, Institute of Evolution, Centre for Ecological Research, Klebelsberg Kunó str. 3., Tihany, 8237, Hungary
- Evolution and Ecology Program, International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, 2361, Laxenburg, Austria
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12
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Preussger D, Giri S, Muhsal LK, Oña L, Kost C. Reciprocal Fitness Feedbacks Promote the Evolution of Mutualistic Cooperation. Curr Biol 2020; 30:3580-3590.e7. [PMID: 32707067 DOI: 10.1016/j.cub.2020.06.100] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 04/29/2020] [Accepted: 06/29/2020] [Indexed: 10/23/2022]
Abstract
Mutually beneficial interactions are ubiquitous in nature and have played a pivotal role for the evolution of life on earth. However, the factors facilitating their emergence remain poorly understood. Here, we address this issue both experimentally and by mathematical modeling using cocultures of auxotrophic strains of Escherichia coli, whose growth depends on a reciprocal exchange of amino acids. Coevolving auxotrophic pairs in a spatially heterogeneous environment for less than 150 generations transformed the initial interaction that was merely based on an exchange of metabolic byproducts into a costly metabolic cooperation, in which both partners increased the amounts of metabolites they produced to benefit their corresponding partner. The observed changes were afforded by the formation of multicellular clusters, within which increased cooperative investments were favored by positive fitness feedbacks among interacting genotypes. Under these conditions, non-cooperative individuals were less fit than cooperative mutants. Together, our results highlight the ease with which mutualistic cooperation can evolve, suggesting similar mechanisms likely operate in natural communities. VIDEO ABSTRACT.
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Affiliation(s)
- Daniel Preussger
- Experimental Ecology and Evolution Research Group, Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Beutenberg Campus, Hans-Knöll Str. 8, Jena 07745, Germany; Department of Ecology, School of Biology/Chemistry, University of Osnabrück, Osnabrück 49076, Germany
| | - Samir Giri
- Experimental Ecology and Evolution Research Group, Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Beutenberg Campus, Hans-Knöll Str. 8, Jena 07745, Germany; Department of Ecology, School of Biology/Chemistry, University of Osnabrück, Osnabrück 49076, Germany
| | - Linéa K Muhsal
- Department of Ecology, School of Biology/Chemistry, University of Osnabrück, Osnabrück 49076, Germany
| | - Leonardo Oña
- Department of Ecology, School of Biology/Chemistry, University of Osnabrück, Osnabrück 49076, Germany
| | - Christian Kost
- Experimental Ecology and Evolution Research Group, Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Beutenberg Campus, Hans-Knöll Str. 8, Jena 07745, Germany; Department of Ecology, School of Biology/Chemistry, University of Osnabrück, Osnabrück 49076, Germany.
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13
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Synthetic Symbiosis under Environmental Disturbances. mSystems 2020; 5:5/3/e00187-20. [PMID: 32546669 PMCID: PMC7300358 DOI: 10.1128/msystems.00187-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The power of synthetic biology is immense. Will it, however, be able to withstand the environmental pressures once released in the wild. As new technologies aim to do precisely the same, we use a much simpler model to test mathematically the effect of a changing environment on a synthetic biological system. We assume that the system is successful if it maintains proportions close to what we observe in the laboratory. Extreme deviations from the expected equilibrium are possible as the environment changes. Our study provides the conditions and the designer specifications which may need to be incorporated in the synthetic systems if we want such “ecoblocs” to survive in the wild. By virtue of complex ecologies, the behavior of mutualisms is challenging to study and nearly impossible to predict. However, laboratory engineered mutualistic systems facilitate a better understanding of their bare essentials. On the basis of an abstract theoretical model and a modifiable experimental yeast system, we explore the environmental limits of self-organized cooperation based on the production and use of specific metabolites. We develop and test the assumptions and stability of the theoretical model by leveraging the simplicity of an artificial yeast system as a simple model of mutualism. We examine how one-off, recurring, and permanent changes to an ecological niche affect a cooperative interaction and change the population composition of an engineered mutualistic system. Moreover, we explore how the cellular burden of cooperating influences the stability of mutualism and how environmental changes shape this stability. Our results highlight the fragility of mutualisms and suggest interventions, including those that rely on the use of synthetic biology. IMPORTANCE The power of synthetic biology is immense. Will it, however, be able to withstand the environmental pressures once released in the wild. As new technologies aim to do precisely the same, we use a much simpler model to test mathematically the effect of a changing environment on a synthetic biological system. We assume that the system is successful if it maintains proportions close to what we observe in the laboratory. Extreme deviations from the expected equilibrium are possible as the environment changes. Our study provides the conditions and the designer specifications which may need to be incorporated in the synthetic systems if we want such “ecoblocs” to survive in the wild.
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14
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Sørensen MES, Lowe CD, Minter EJA, Wood AJ, Cameron DD, Brockhurst MA. The role of exploitation in the establishment of mutualistic microbial symbioses. FEMS Microbiol Lett 2020; 366:5528313. [PMID: 31271421 PMCID: PMC6638607 DOI: 10.1093/femsle/fnz148] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 07/01/2019] [Indexed: 12/12/2022] Open
Abstract
Evolutionary theory suggests that the conditions required for the establishment of mutualistic symbioses through mutualism alone are highly restrictive, often requiring the evolution of complex stabilising mechanisms. Exploitation, whereby initially the host benefits at the expense of its symbiotic partner and mutual benefits evolve subsequently through trade-offs, offers an arguably simpler route to the establishment of mutualistic symbiosis. In this review, we discuss the theoretical and experimental evidence supporting a role for host exploitation in the establishment and evolution of mutualistic microbial symbioses, including data from both extant and experimentally evolved symbioses. We conclude that exploitation rather than mutualism may often explain the origin of mutualistic microbial symbioses.
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Affiliation(s)
- Megan E S Sørensen
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Chris D Lowe
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Cornwall TR10 9FE, UK
| | - Ewan J A Minter
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - A Jamie Wood
- Department of Biology, University of York, York YO10 5DD, UK.,Department of Mathematics, University of York, York YO10 5DD, UK
| | - Duncan D Cameron
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Michael A Brockhurst
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
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15
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Oosthuizen JR, Naidoo RK, Rossouw D, Bauer FF. Evolution of mutualistic behaviour between Chlorella sorokiniana and Saccharomyces cerevisiae within a synthetic environment. J Ind Microbiol Biotechnol 2020; 47:357-372. [PMID: 32385605 DOI: 10.1007/s10295-020-02280-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 05/02/2020] [Indexed: 02/06/2023]
Abstract
Yeast and microalgae are microorganisms with widely diverging physiological and biotechnological properties. Accordingly, their fields of applications diverge: yeasts are primarily applied in processes related to fermentation, while microalgae are used for the production of high-value metabolites and green technologies such as carbon capture. Heterotrophic-autotrophic systems and synthetic ecology approaches have been proposed as tools to achieve stable combinations of such evolutionarily unrelated species. We describe an entirely novel synthetic ecology-based approach to evolve co-operative behaviour between winery wastewater isolates of the yeast Saccharomyces cerevisiae and microalga Chlorella sorokiniana. The data show that biomass production and mutualistic growth improved when co-evolved yeast and microalgae strains were paired together. Combinations of co-evolved strains displayed a range of phenotypes, including differences in amino acid profiles. Taken together, the results demonstrate that biotic selection pressures can lead to improved mutualistic growth phenotypes over relatively short time periods.
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Affiliation(s)
- J R Oosthuizen
- Department of Viticulture and Oenology, Institute for Wine Biotechnology, Stellenbosch University, Stellenbosch, South Africa
| | - R K Naidoo
- Department of Viticulture and Oenology, Institute for Wine Biotechnology, Stellenbosch University, Stellenbosch, South Africa
| | - D Rossouw
- Department of Viticulture and Oenology, Institute for Wine Biotechnology, Stellenbosch University, Stellenbosch, South Africa
| | - F F Bauer
- Department of Viticulture and Oenology, Institute for Wine Biotechnology, Stellenbosch University, Stellenbosch, South Africa.
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16
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Giri S, Waschina S, Kaleta C, Kost C. Defining Division of Labor in Microbial Communities. J Mol Biol 2019; 431:4712-4731. [PMID: 31260694 DOI: 10.1016/j.jmb.2019.06.023] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 06/13/2019] [Accepted: 06/19/2019] [Indexed: 11/15/2022]
Abstract
In order to survive and reproduce, organisms must perform a multitude of tasks. However, trade-offs limit their ability to allocate energy and resources to all of these different processes. One strategy to solve this problem is to specialize in some traits and team up with other organisms that can help by providing additional, complementary functions. By reciprocally exchanging metabolites and/or services in this way, both parties benefit from the interaction. This phenomenon, which has been termed functional specialization or division of labor, is very common in nature and exists on all levels of biological organization. Also, microorganisms have evolved different types of synergistic interactions. However, very often, it remains unclear whether or not a given example represents a true case of division of labor. Here we aim at filling this gap by providing a list of criteria that clearly define division of labor in microbial communities. Furthermore, we propose a set of diagnostic experiments to verify whether a given interaction fulfills these conditions. In contrast to the common use of the term, our analysis reveals that both intraspecific and interspecific interactions meet the criteria defining division of labor. Moreover, our analysis identified non-cooperators of intraspecific public goods interactions as growth specialists that divide labor with conspecific producers, rather than being social parasites. By providing a conceptual toolkit, our work will help to unambiguously identify cases of division of labor and stimulate more detailed investigations of this important and widespread type of inter-microbial interaction.
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Affiliation(s)
- Samir Giri
- Department of Ecology, School of Biology/Chemistry, University of Osnabrück, Osnabrück, Germany
| | - Silvio Waschina
- Research Group Medical Systems Biology, Institute for Experimental Medicine, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Christoph Kaleta
- Research Group Medical Systems Biology, Institute for Experimental Medicine, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Christian Kost
- Department of Ecology, School of Biology/Chemistry, University of Osnabrück, Osnabrück, Germany.
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17
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Shitut S, Ahsendorf T, Pande S, Egbert M, Kost C. Nanotube-mediated cross-feeding couples the metabolism of interacting bacterial cells. Environ Microbiol 2019; 21:1306-1320. [PMID: 30680926 DOI: 10.1111/1462-2920.14539] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 01/22/2019] [Indexed: 12/11/2022]
Abstract
Bacteria frequently engage in cross-feeding interactions that involve an exchange of metabolites with other micro- or macroorganisms. The often obligate nature of these associations, however, hampers manipulative experiments, thus limiting our mechanistic understanding of the ecophysiological consequences that result for the organisms involved. Here we address this issue by taking advantage of a well-characterized experimental model system, in which auxotrophic genotypes of E. coli derive essential amino acids from prototrophic donor cells using intercellular nanotubes. Surprisingly, donor-recipient cocultures revealed that the mere presence of auxotrophic genotypes was sufficient to increase amino acid production levels of several prototrophic donor genotypes. Our work is consistent with a scenario, in which interconnected auxotrophs withdraw amino acids from the cytoplasm of donor cells, which delays feedback inhibition of the corresponding amino acid biosynthetic pathway and, in this way, increases amino acid production levels. Our findings indicate that in newly established mutualistic associations, an intercellular regulation of exchanged metabolites can simply emerge from the architecture of the underlying biosynthetic pathways, rather than requiring the evolution of new regulatory mechanisms.
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Affiliation(s)
- Shraddha Shitut
- Experimental Ecology and Evolution Research Group, Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Jena 07745, Germany.,Department of Ecology, School of Biology/Chemistry, University of Osnabrück, Osnabrück 49076, Germany
| | - Tobias Ahsendorf
- Deutsches Krebsforschungszentrum, Baden-Württemberg 69120, Heidelberg, Germany.,Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Samay Pande
- Experimental Ecology and Evolution Research Group, Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
| | - Matthew Egbert
- Department of Computer Science, University of Auckland, Auckland 1010, New Zealand
| | - Christian Kost
- Experimental Ecology and Evolution Research Group, Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Jena 07745, Germany.,Department of Ecology, School of Biology/Chemistry, University of Osnabrück, Osnabrück 49076, Germany
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18
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Shu L, Brock DA, Geist KS, Miller JW, Queller DC, Strassmann JE, DiSalvo S. Symbiont location, host fitness, and possible coadaptation in a symbiosis between social amoebae and bacteria. eLife 2018; 7:e42660. [PMID: 30596477 PMCID: PMC6336404 DOI: 10.7554/elife.42660] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 12/30/2018] [Indexed: 12/14/2022] Open
Abstract
Recent symbioses, particularly facultative ones, are well suited for unravelling the evolutionary give and take between partners. Here we look at variation in natural isolates of the social amoeba Dictyostelium discoideum and their relationships with bacterial symbionts, Burkholderia hayleyella and Burkholderia agricolaris. Only about a third of field-collected amoebae carry a symbiont. We cured and cross-infected amoebae hosts with different symbiont association histories and then compared host responses to each symbiont type. Before curing, field-collected clones did not vary significantly in overall fitness, but infected hosts produced morphologically different multicellular structures. After curing and reinfecting, host fitness declined. However, natural B. hayleyella hosts suffered fewer fitness costs when reinfected with B. hayleyella, indicating that they have evolved mechanisms to tolerate their symbiont. Our work suggests that amoebae hosts have evolved mechanisms to tolerate specific acquired symbionts; exploring host-symbiont relationships that vary within species may provide further insights into disease dynamics.
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Affiliation(s)
- Longfei Shu
- Environmental Microbiomics Research Center and Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and EngineeringSun Yat-sen UniversityGuangzhouChina
- Department of BiologyWashington UniversitySt LouisUnited States
| | - Debra A Brock
- Department of BiologyWashington UniversitySt LouisUnited States
| | | | - Jacob W Miller
- Department of Biological SciencesSouthern Illinois UniversityEdwardsvilleUnited States
| | - David C Queller
- Department of BiologyWashington UniversitySt LouisUnited States
| | | | - Susanne DiSalvo
- Department of Biological SciencesSouthern Illinois UniversityEdwardsvilleUnited States
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19
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Abstract
All multicellular organisms are colonized by microbes, but a gestalt study of the composition of microbiome communities and their influence on the ecology and evolution of their macroscopic hosts has only recently become possible. One approach to thinking about the topic is to view the host–microbiome ecosystem as a “holobiont”. Because natural selection acts on an organism’s realized phenotype, and the phenotype of a holobiont is the result of the integrated activities of both the host and all of its microbiome inhabitants, it is reasonable to think that evolution can act at the level of the holobiont and cause changes in the “hologenome”, or the collective genomic content of all the individual bionts within the holobiont. This relatively simple assertion has nevertheless been controversial within the microbiome community. Here, I provide a review of recent work on the hologenome concept of evolution. I attempt to provide a clear definition of the concept and its implications and to clarify common points of disagreement.
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Affiliation(s)
- J Jeffrey Morris
- Department of Biology, University of Alabama at Birmingham, Birmingham, Alabama, USA
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20
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Minter EJA, Lowe CD, Sørensen MES, Wood AJ, Cameron DD, Brockhurst MA. Variation and asymmetry in host-symbiont dependence in a microbial symbiosis. BMC Evol Biol 2018; 18:108. [PMID: 29986646 PMCID: PMC6038246 DOI: 10.1186/s12862-018-1227-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 06/29/2018] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Symbiosis is a major source of evolutionary innovation and, by allowing species to exploit new ecological niches, underpins the functioning of ecosystems. The transition from free-living to obligate symbiosis requires the alignment of the partners' fitness interests and the evolution of mutual dependence. While symbiotic taxa are known to vary widely in the extent of host-symbiont dependence, rather less is known about variation within symbiotic associations. RESULTS Using experiments with the microbial symbiosis between the protist Paramecium bursaria and the alga Chlorella, we show variation between pairings in host-symbiont dependence, encompassing facultative associations, mutual dependence and host dependence upon the symbiont. Facultative associations, that is where both the host and the symbiont were capable of free-living growth, displayed higher symbiotic growth rates and higher per host symbiont loads than those with greater degrees of dependence. CONCLUSIONS These data show that the Paramecium-Chlorella interaction exists at the boundary between facultative and obligate symbiosis, and further suggest that the host is more likely to evolve dependence than the algal symbiont.
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Affiliation(s)
- Ewan J A Minter
- Department of Animal and Plant Sciences, University of Sheffield, Alfred Denny Building, Western Bank, Sheffield, S10 2TN, UK
| | - Chris D Lowe
- Centre for Ecology and Conservation, University of Exeter, Penryn, TR10 9FE, UK
| | - Megan E S Sørensen
- Department of Animal and Plant Sciences, University of Sheffield, Alfred Denny Building, Western Bank, Sheffield, S10 2TN, UK
| | - A Jamie Wood
- Department of Biology, University of York, York, YO10 5DD, UK.,Department of Mathematics, University of York, York, YO10 5DD, UK
| | - Duncan D Cameron
- Department of Animal and Plant Sciences, University of Sheffield, Alfred Denny Building, Western Bank, Sheffield, S10 2TN, UK
| | - Michael A Brockhurst
- Department of Animal and Plant Sciences, University of Sheffield, Alfred Denny Building, Western Bank, Sheffield, S10 2TN, UK.
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21
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D'Souza G, Shitut S, Preussger D, Yousif G, Waschina S, Kost C. Ecology and evolution of metabolic cross-feeding interactions in bacteria. Nat Prod Rep 2018; 35:455-488. [PMID: 29799048 DOI: 10.1039/c8np00009c] [Citation(s) in RCA: 230] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Literature covered: early 2000s to late 2017Bacteria frequently exchange metabolites with other micro- and macro-organisms. In these often obligate cross-feeding interactions, primary metabolites such as vitamins, amino acids, nucleotides, or growth factors are exchanged. The widespread distribution of this type of metabolic interactions, however, is at odds with evolutionary theory: why should an organism invest costly resources to benefit other individuals rather than using these metabolites to maximize its own fitness? Recent empirical work has shown that bacterial genotypes can significantly benefit from trading metabolites with other bacteria relative to cells not engaging in such interactions. Here, we will provide a comprehensive overview over the ecological factors and evolutionary mechanisms that have been identified to explain the evolution and maintenance of metabolic mutualisms among microorganisms. Furthermore, we will highlight general principles that underlie the adaptive evolution of interconnected microbial metabolic networks as well as the evolutionary consequences that result for cells living in such communities.
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Affiliation(s)
- Glen D'Souza
- Department of Environmental Systems Sciences, ETH-Zürich, Zürich, Switzerland
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22
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Bourrat P, Griffiths PE. Multispecies individuals. HISTORY AND PHILOSOPHY OF THE LIFE SCIENCES 2018; 40:33. [PMID: 29761370 DOI: 10.1007/s40656-018-0194-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 04/05/2018] [Indexed: 06/08/2023]
Abstract
We assess the arguments for recognising functionally integrated multispecies consortia as genuine biological individuals, including cases of so-called 'holobionts'. We provide two examples in which the same core biochemical processes that sustain life are distributed across a consortium of individuals of different species. Although the same chemistry features in both examples, proponents of the holobiont as unit of evolution would recognize one of the two cases as a multispecies individual whilst they would consider the other as a compelling case of ecological dependence between separate individuals. Some widely used arguments in support of the 'holobiont' concept apply equally to both cases, suggesting that those arguments have misidentified what is at stake when seeking to identify a new level of biological individuality. One important aspect of biological individuality is evolutionary individuality. In line with other work on the evolution of individuality, we show that our cases can be distinguished by focusing on the fitness alignment between the partners of the consortia. We conclude that much of the evidence currently presented for the ubiquity and importance of multi-species individuals is simply not to the point, at least unless the issue of biological individuality is firmly divorced from the question of evolutionary individuality.
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Affiliation(s)
- Pierrick Bourrat
- Department of Philosophy, Macquarie University, North Ryde, NSW, 2109, Australia.
- School of History and Philosophy of Science, University of Sydney, Main Quadrangle A14, Sydney, NSW, 2006, Australia.
- Department of Philosophy and Charles Perkins Centre, University of Sydney, Main Quadrangle A14, Sydney, NSW, 2006, Australia.
| | - Paul E Griffiths
- Department of Philosophy and Charles Perkins Centre, University of Sydney, Main Quadrangle A14, Sydney, NSW, 2006, Australia
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23
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Doolittle WF, Inkpen SA. Processes and patterns of interaction as units of selection: An introduction to ITSNTS thinking. Proc Natl Acad Sci U S A 2018; 115:4006-4014. [PMID: 29581311 PMCID: PMC5910863 DOI: 10.1073/pnas.1722232115] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Many practicing biologists accept that nothing in their discipline makes sense except in the light of evolution, and that natural selection is evolution's principal sense-maker. But what natural selection actually is (a force or a statistical outcome, for example) and the levels of the biological hierarchy (genes, organisms, species, or even ecosystems) at which it operates directly are still actively disputed among philosophers and theoretical biologists. Most formulations of evolution by natural selection emphasize the differential reproduction of entities at one or the other of these levels. Some also recognize differential persistence, but in either case the focus is on lineages of material things: even species can be thought of as spatiotemporally restricted, if dispersed, physical beings. Few consider-as "units of selection" in their own right-the processes implemented by genes, cells, species, or communities. "It's the song not the singer" (ITSNTS) theory does that, also claiming that evolution by natural selection of processes is more easily understood and explained as differential persistence than as differential reproduction. ITSNTS was formulated as a response to the observation that the collective functions of microbial communities (the songs) are more stably conserved and ecologically relevant than are the taxa that implement them (the singers). It aims to serve as a useful corrective to claims that "holobionts" (microbes and their animal or plant hosts) are aggregate "units of selection," claims that often conflate meanings of that latter term. But ITSNS also seems broadly applicable, for example, to the evolution of global biogeochemical cycles and the definition of ecosystem function.
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Affiliation(s)
- W Ford Doolittle
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada;
| | - S Andrew Inkpen
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada
- Department of Philosophy, Dalhousie University, Halifax, NS B3H 4R2, Canada
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24
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O’Malley MA, Skillings DJ. Methodological Strategies in Microbiome Research and their Explanatory Implications. ACTA ACUST UNITED AC 2018. [DOI: 10.1162/posc_a_00274] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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25
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Life and death in facultative chemosymbioses: control of bacterial population dynamics in the Thyasiridae. Symbiosis 2017. [DOI: 10.1007/s13199-017-0525-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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26
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On the origin of biological construction, with a focus on multicellularity. Proc Natl Acad Sci U S A 2017; 114:11018-11026. [PMID: 28973893 DOI: 10.1073/pnas.1704631114] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Biology is marked by a hierarchical organization: all life consists of cells; in some cases, these cells assemble into groups, such as endosymbionts or multicellular organisms; in turn, multicellular organisms sometimes assemble into yet other groups, such as primate societies or ant colonies. The construction of new organizational layers results from hierarchical evolutionary transitions, in which biological units (e.g., cells) form groups that evolve into new units of biological organization (e.g., multicellular organisms). Despite considerable advances, there is no bottom-up, dynamical account of how, starting from the solitary ancestor, the first groups originate and subsequently evolve the organizing principles that qualify them as new units. Guided by six central questions, we propose an integrative bottom-up approach for studying the dynamics underlying hierarchical evolutionary transitions, which builds on and synthesizes existing knowledge. This approach highlights the crucial role of the ecology and development of the solitary ancestor in the emergence and subsequent evolution of groups, and it stresses the paramount importance of the life cycle: only by evaluating groups in the context of their life cycle can we unravel the evolutionary trajectory of hierarchical transitions. These insights also provide a starting point for understanding the types of subsequent organizational complexity. The central research questions outlined here naturally link existing research programs on biological construction (e.g., on cooperation, multilevel selection, self-organization, and development) and thereby help integrate knowledge stemming from diverse fields of biology.
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27
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Fisher RM, Henry LM, Cornwallis CK, Kiers ET, West SA. The evolution of host-symbiont dependence. Nat Commun 2017; 8:15973. [PMID: 28675159 PMCID: PMC5500886 DOI: 10.1038/ncomms15973] [Citation(s) in RCA: 158] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 05/15/2017] [Indexed: 11/09/2022] Open
Abstract
Organisms across the tree of life form symbiotic partnerships with microbes for metabolism, protection and resources. While some hosts evolve extreme dependence on their symbionts, others maintain facultative associations. Explaining this variation is fundamental to understanding when symbiosis can lead to new higher-level individuals, such as during the evolution of the eukaryotic cell. Here we perform phylogenetic comparative analyses on 106 unique host-bacterial symbioses to test for correlations between symbiont function, transmission mode, genome size and host dependence. We find that both transmission mode and symbiont function are correlated with host dependence, with reductions in host fitness being greatest when nutrient-provisioning, vertically transmitted symbionts are removed. We also find a negative correlation between host dependence and symbiont genome size in vertically, but not horizontally, transmitted symbionts. These results suggest that both function and population structure are important in driving irreversible dependence between hosts and symbionts.
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Affiliation(s)
- Roberta M Fisher
- Department of Ecological Science, Faculty of Earth and Life Sciences, Vrije Universiteit, De Boelelaan 1085-1087, 1081 HV Amsterdam, The Netherlands.,Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| | - Lee M Henry
- School of Biological and Chemical Sciences, Queen Mary University of London, London E1 4NS, UK
| | | | - E Toby Kiers
- Department of Ecological Science, Faculty of Earth and Life Sciences, Vrije Universiteit, De Boelelaan 1085-1087, 1081 HV Amsterdam, The Netherlands
| | - Stuart A West
- Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
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28
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Caron DA, Alexander H, Allen AE, Archibald JM, Armbrust EV, Bachy C, Bell CJ, Bharti A, Dyhrman ST, Guida SM, Heidelberg KB, Kaye JZ, Metzner J, Smith SR, Worden AZ. Probing the evolution, ecology and physiology of marine protists using transcriptomics. Nat Rev Microbiol 2016; 15:6-20. [DOI: 10.1038/nrmicro.2016.160] [Citation(s) in RCA: 128] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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29
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Díaz-Muñoz SL, Boddy AM, Dantas G, Waters CM, Bronstein JL. Contextual organismality: Beyond pattern to process in the emergence of organisms. Evolution 2016; 70:2669-2677. [PMID: 27704542 PMCID: PMC5132100 DOI: 10.1111/evo.13078] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 09/06/2016] [Accepted: 09/24/2016] [Indexed: 12/19/2022]
Abstract
Biologists have taken the concept of organism largely for granted. However, advances in the study of chimerism, symbiosis, bacterial‐eukaryote associations, and microbial behavior have prompted a redefinition of organisms as biological entities exhibiting low conflict and high cooperation among their parts. This expanded view identifies organisms in evolutionary time. However, the ecological processes, mechanisms, and traits that drive the formation of organisms remain poorly understood. Recognizing that organismality can be context dependent, we advocate elucidating the ecological contexts under which entities do or do not act as organisms. Here we develop a “contextual organismality” framework and provide examples of entities, such as honey bee colonies, tumors, and bacterial swarms, that can act as organisms under specific life history, resource, or other ecological circumstances. We suggest that context dependence may be a stepping stone to the development of increased organismal unification, as the most integrated biological entities generally show little context dependence. Recognizing that organismality is contextual can identify common patterns and testable hypotheses across different entities. The contextual organismality framework can illuminate timeless as well as pressing issues in biology, including topics as disparate as cancer emergence, genomic conflict, evolution of symbiosis, and the role of the microbiota in impacting host phenotype.
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Affiliation(s)
- Samuel L Díaz-Muñoz
- Center for Genomics and Systems Biology and Department of Biology, New York University, New York, New York, 10003
| | - Amy M Boddy
- Department of Psychology, Arizona State University, Tempe, Arizona, 85281
| | - Gautam Dantas
- Department of Pathology and Immunology, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri, 63110
| | - Christopher M Waters
- Department of Microbiology and Molecular Genetics, 5180 Biomedical Physical Sciences, Michigan State University, East Lansing, Michigan, 48824
| | - Judith L Bronstein
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona, 85721
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