1
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Nuño de la Rosa L. Agency in Reproduction. Evol Dev 2023; 25:418-429. [PMID: 37243316 DOI: 10.1111/ede.12440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 03/22/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023]
Abstract
While niche construction theory and developmental approaches to evolution have brought to the front the active role of organisms as ecological and developmental agents, respectively, the role of agents in reproduction has been widely neglected by organismal perspectives of evolution. This paper addresses this problem by proposing an agential view of reproduction and shows that such a perspective has implications for the explanation of the origin of modes of reproduction, the evolvability of reproductive modes, and the coevolution between reproduction and social behavior. After introducing the two prevalent views of agency in evolutionary biology, namely those of organismal agency and selective agency, I contrast these two perspectives as applied to the evolution of animal reproduction. Taking eutherian pregnancy as a case study, I wonder whether organismal approaches to agency forged in the frame of niche construction and developmental plasticity theories can account for the goal-directed activities involved in reproductive processes. I conclude that the agential role of organisms in reproduction is irreducible to developmental and ecological agency, and that reproductive goals need to be included into our definitions of organismal agency. I then explore the evolutionary consequences of endorsing an agential approach to reproduction, showing how such an approach might illuminate our understanding of the evolutionary origination and developmental evolvability of reproductive modes. Finally, I analyze recent studies on the coevolution between viviparity and social behavior in vertebrates to suggest that an agential notion of reproduction can provide unforeseen links between developmental and ecological agency.
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Affiliation(s)
- Laura Nuño de la Rosa
- Department of Logic and Theoretical Philosophy, Complutense University of Madrid, Madrid, Spain
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2
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Alarcón-Ríos L, Velo-Antón G. Multiple paternity in the pueriparous North African fire salamander, Salamandra algira, supports polyandry as a successful mating strategy in low fecundity Salamandra lineages. AMPHIBIA-REPTILIA 2021. [DOI: 10.1163/15685381-bja10075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Multiple paternity is widespread in nature and despite costs, it has many associated benefits like increased genetic diversity and fertilization success. It has been described in many viviparous systems, suggesting the existence of some fitness advantages counteracting the inherent costs of viviparity, such as fecundity reduction and high parental investment. Reproductively polymorphic species, like the urodele Salamandra algira, which shows two types of viviparity: larviparity (i.e., delivering aquatic larvae), and pueriparity (i.e., delivering terrestrial metamorphosed juveniles), are suitable systems to study the relationship between reproductive modes and polygamous mating. Here, multiple paternity is confirmed in a pueriparous lineage of S. algira, as previously verified for the pueriparous lineages of the reproductively polymorphic species S. salamandra, suggesting polyandry is a successful mating strategy in pueriparous systems with reduced brood sizes. We discuss the potential benefits of polyandry in the context of viviparity evolution in urodeles.
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Affiliation(s)
- Lucía Alarcón-Ríos
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, 4485-661 Vairão, Portugal
- BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661 Vairão, Portugal
| | - Guillermo Velo-Antón
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, 4485-661 Vairão, Portugal
- BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661 Vairão, Portugal
- Universidade de Vigo, Departamento de Ecoloxía e Bioloxía Animal, Grupo de Ecoloxía Animal, Torre Cacti (Lab 97), E-36310, Vigo, Spain
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3
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Furness AI, Hagmayer A, Pollux BJA. Female reproductive mode shapes allometric scaling of male traits in live-bearing fishes (family Poeciliidae). J Evol Biol 2021; 34:1144-1155. [PMID: 34081811 DOI: 10.1111/jeb.13875] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 04/22/2021] [Accepted: 05/12/2021] [Indexed: 11/26/2022]
Abstract
Reproductive mode is predicted to influence the form of sexual selection. The viviparity-driven conflict hypothesis posits that a shift from lecithotrophic (yolk-nourished) to matrotrophic (mother-nourished or placental) viviparity drives a shift from precopulatory towards post-copulatory sexual selection. In lecithotrophic species, we predict that precopulatory sexual selection will manifest as males exhibiting a broad distribution of sizes, and small and large males exhibiting contrasting phenotypes (morphology and coloration); conversely, in matrotrophic species, an emphasis on post-copulatory sexual selection will preclude these patterns. We test these predictions by gathering data on male size, morphology and coloration for five sympatric Costa Rican poeciliid species that differ in reproductive mode (i.e. lecithotrophy vs. matrotrophy). We find tentative support for these predictions of the viviparity-driven conflict hypothesis, with some interesting caveats and subtleties. In particular, we find that the three lecithotrophic species tend to show a broader distribution of male sizes than matrotrophic species. Furthermore, large males of such species tend to exhibit proportionately large dorsal and caudal fins and short gonopodia relative to small males, while these patterns are expressed to a lesser extent in the two matrotrophic species. Finally, large males in some of the lecithotrophic species exhibit darker fins relative to small males, a pattern not evident in either matrotrophic species. One unexpected finding was that even in the matrotrophic species Poeciliopsis retropinna and Poeciliopsis paucimaculata, which lack courtship and dichromatic coloration, some morphological traits exhibit significant allometric relationships, suggesting that even in these species precopulatory sexual selection may be present and shaping size-specific male phenotypes in subtle ways.
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Affiliation(s)
- Andrew I Furness
- Department of Biological and Marine Sciences, University of Hull, Hull, UK
| | - Andres Hagmayer
- Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
| | - Bart J A Pollux
- Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
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4
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Reznick DN, Travis J, Pollux BJA, Furness AI. Reproductive Mode and Conflict Shape the Evolution of Male Attributes and Rate of Speciation in the Fish Family Poeciliidae. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.639751] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Sexual conflict is caused by differences between the sexes in how fitness is maximized. These differences are shaped by the discrepancy in the investment in gametes, how mates are chosen and how embryos and young are provided for. Fish in the family Poeciliidae vary from completely provisioning eggs before they are fertilized to providing virtually all resources after fertilization via the functional equivalent of a mammalian placenta. This shift in when females provision their young relative to when an egg is fertilized is predicted to cause a fundamental change in when and how sexual conflict is manifested. If eggs are provisioned before fertilization, there should be strong selection for females to choose with whom they mate. Maternal provisioning after fertilization should promote a shift to post-copulatory mate choice. The evolution of maternal provisioning may in turn have cascading effects on the evolution of diverse features of the biology of these fish because of this shift in when mates are chosen. Here we summarize what these consequences are and show that the evolution of maternal provisioning is indeed associated with and appears to govern the evolution of male traits associated with sexual selection. The evolution of placentas and associated conflict does not cause accelerated speciation, contrary to predictions. Accelerated speciation rate is instead correlated with the evolution of male traits associated with sexual selection, which implies a more prominent role of pre-copulatory reproductive isolation in causing speciation in this family.
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5
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The evolution of the placenta in poeciliid fishes. Curr Biol 2021; 31:2004-2011.e5. [DOI: 10.1016/j.cub.2021.02.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 12/02/2020] [Accepted: 02/03/2021] [Indexed: 01/05/2023]
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6
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Dezetter M, Le Galliard JF, Guiller G, Guillon M, Leroux-Coyau M, Meylan S, Brischoux F, Angelier F, Lourdais O. Water deprivation compromises maternal physiology and reproductive success in a cold and wet adapted snake Vipera berus. CONSERVATION PHYSIOLOGY 2021; 9:coab071. [PMID: 34512993 PMCID: PMC8415537 DOI: 10.1093/conphys/coab071] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 07/16/2021] [Accepted: 08/05/2021] [Indexed: 05/05/2023]
Abstract
Droughts are becoming more intense and frequent with climate change. These extreme weather events can lead to mass mortality and reproduction failure, and therefore cause population declines. Understanding how the reproductive physiology of organisms is affected by water shortages will help clarify whether females can adjust their reproductive strategy to dry conditions or may fail to reproduce and survive. In this study, we investigated the consequences of a short period of water deprivation (2 weeks) during early pregnancy on the physiology and behaviour of a cold- and wet-adapted ectotherm (Vipera berus). We also examined water allocation to developing embryos and embryonic survival. Water-deprived females exhibited significant dehydration, physiological stress and loss of muscle mass. These effects of water deprivation on water balance and muscle loss were correlated with the number of developing embryos. While water-deprived females maintained water transfer to embryos at the expense of their own maintenance, water deprivation also led to embryonic mortality. Overall, water deprivation amplifies the reproductive costs of water allocation to support embryonic development. The deleterious impacts of water deprivation on female current reproductive performance and on potential survival and future reproduction could lead to severe population declines in this species.
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Affiliation(s)
- Mathias Dezetter
- Sorbonne University, CNRS, IRD, INRA, Institut d’Écologie et des Sciences de l’Environnement (iEES Paris), 4 Place Jussieu, 75252 Paris Cedex 5, France
- Centre d’Études Biologiques de Chizé CNRS, UMR 7372, 79360 Villiers en Bois, France
- Corresponding author: Centre d’Étude Biologique de Chizé CNRS, UMR 7372, 79360 Villiers en Bois, France. Tel: + 33 (0) 5 49 09 35 52. Fax: + 33 (0) 5 49 09 65 26.
| | - Jean François Le Galliard
- Sorbonne University, CNRS, IRD, INRA, Institut d’Écologie et des Sciences de l’Environnement (iEES Paris), 4 Place Jussieu, 75252 Paris Cedex 5, France
- Ecole Normale Supérieure, PSL University, Département de Biologie, CNRS, UMS 3194, Centre de Recherche en Écologie Expérimentale et Prédictive (CEREEP-Ecotron IleDeFrance), 11 Chemin de Busseau, 77140 Saint-Pierre lès-Nemours, France
| | | | - Michaël Guillon
- Centre d’Études Biologiques de Chizé CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Mathieu Leroux-Coyau
- Sorbonne University, CNRS, IRD, INRA, Institut d’Écologie et des Sciences de l’Environnement (iEES Paris), 4 Place Jussieu, 75252 Paris Cedex 5, France
| | - Sandrine Meylan
- Sorbonne University, CNRS, IRD, INRA, Institut d’Écologie et des Sciences de l’Environnement (iEES Paris), 4 Place Jussieu, 75252 Paris Cedex 5, France
- INSPE de Paris, Université Sorbonne, 10 rue Molitor, 75016 Paris, France
| | - François Brischoux
- Centre d’Études Biologiques de Chizé CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Fréderic Angelier
- Centre d’Études Biologiques de Chizé CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Olivier Lourdais
- Centre d’Études Biologiques de Chizé CNRS, UMR 7372, 79360 Villiers en Bois, France
- School of Life Sciences, Arizona State University, Tempe, AZ 85287-4501, USA
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7
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Hallin J, Cisneros AF, Hénault M, Fijarczyk A, Dandage R, Bautista C, Landry CR. Similarities in biological processes can be used to bridge ecology and molecular biology. Evol Appl 2020; 13:1335-1350. [PMID: 32684962 PMCID: PMC7359829 DOI: 10.1111/eva.12961] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 02/17/2020] [Accepted: 03/16/2020] [Indexed: 01/10/2023] Open
Abstract
Much of the research in biology aims to understand the origin of diversity. Naturally, ecological diversity was the first object of study, but we now have the necessary tools to probe diversity at molecular scales. The inherent differences in how we study diversity at different scales caused the disciplines of biology to be organized around these levels, from molecular biology to ecology. Here, we illustrate that there are key properties of each scale that emerge from the interactions of simpler components and that these properties are often shared across different levels of organization. This means that ideas from one level of organization can be an inspiration for novel hypotheses to study phenomena at another level. We illustrate this concept with examples of events at the molecular level that have analogs at the organismal or ecological level and vice versa. Through these examples, we illustrate that biological processes at different organization levels are governed by general rules. The study of the same phenomena at different scales could enrich our work through a multidisciplinary approach, which should be a staple in the training of future scientists.
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Affiliation(s)
- Johan Hallin
- Département de biochimie de microbiologie et de bio-informatique Faculté des sciences et de génie Université Laval Québec Canada.,Département de biologie Faculté des sciences et de génie Université Laval Québec Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec Canada.,PROTEO Le réseau québécois de recherche sur la fonction la structure et l'ingénierie des protéines Université Laval Québec Canada.,Centre de Recherche en Données Massives (CRDM) Université Laval Québec Canada
| | - Angel F Cisneros
- Département de biochimie de microbiologie et de bio-informatique Faculté des sciences et de génie Université Laval Québec Canada.,Département de biologie Faculté des sciences et de génie Université Laval Québec Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec Canada.,PROTEO Le réseau québécois de recherche sur la fonction la structure et l'ingénierie des protéines Université Laval Québec Canada.,Centre de Recherche en Données Massives (CRDM) Université Laval Québec Canada
| | - Mathieu Hénault
- Département de biochimie de microbiologie et de bio-informatique Faculté des sciences et de génie Université Laval Québec Canada.,Département de biologie Faculté des sciences et de génie Université Laval Québec Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec Canada.,PROTEO Le réseau québécois de recherche sur la fonction la structure et l'ingénierie des protéines Université Laval Québec Canada.,Centre de Recherche en Données Massives (CRDM) Université Laval Québec Canada
| | - Anna Fijarczyk
- Département de biochimie de microbiologie et de bio-informatique Faculté des sciences et de génie Université Laval Québec Canada.,Département de biologie Faculté des sciences et de génie Université Laval Québec Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec Canada.,PROTEO Le réseau québécois de recherche sur la fonction la structure et l'ingénierie des protéines Université Laval Québec Canada.,Centre de Recherche en Données Massives (CRDM) Université Laval Québec Canada
| | - Rohan Dandage
- Département de biochimie de microbiologie et de bio-informatique Faculté des sciences et de génie Université Laval Québec Canada.,Département de biologie Faculté des sciences et de génie Université Laval Québec Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec Canada.,PROTEO Le réseau québécois de recherche sur la fonction la structure et l'ingénierie des protéines Université Laval Québec Canada.,Centre de Recherche en Données Massives (CRDM) Université Laval Québec Canada
| | - Carla Bautista
- Département de biochimie de microbiologie et de bio-informatique Faculté des sciences et de génie Université Laval Québec Canada.,Département de biologie Faculté des sciences et de génie Université Laval Québec Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec Canada.,PROTEO Le réseau québécois de recherche sur la fonction la structure et l'ingénierie des protéines Université Laval Québec Canada.,Centre de Recherche en Données Massives (CRDM) Université Laval Québec Canada
| | - Christian R Landry
- Département de biochimie de microbiologie et de bio-informatique Faculté des sciences et de génie Université Laval Québec Canada.,Département de biologie Faculté des sciences et de génie Université Laval Québec Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec Canada.,PROTEO Le réseau québécois de recherche sur la fonction la structure et l'ingénierie des protéines Université Laval Québec Canada.,Centre de Recherche en Données Massives (CRDM) Université Laval Québec Canada
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8
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Abstract
Parental care is extremely diverse across species, ranging from simple behaviours to complex adaptations, varying in duration and in which sex cares. Surprisingly, we know little about how such diversity has evolved. Here, using phylogenetic comparative methods and data for over 1300 amphibian species, we show that egg attendance, arguably one of the simplest care behaviours, is gained and lost faster than any other care form, while complex adaptations, like brooding and viviparity, are lost at very low rates, if at all. Prolonged care from the egg to later developmental stages evolves from temporally limited care, but it is as easily lost as it is gained. Finally, biparental care is evolutionarily unstable regardless of whether the parents perform complementary or similar care duties. By considering the full spectrum of parental care adaptations, our study reveals a more complex and nuanced picture of how care evolves, is maintained, or is lost. Parental care can take many forms but how this diversity arises is not well understood. Here, the authors compile data for over 1300 amphibian species and show that different forms of care evolve at different rates, prolonged care can be easily reduced, and biparental care is evolutionarily unstable.
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9
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Furness AI, Pollux BJA, Meredith RW, Springer MS, Reznick DN. How conflict shapes evolution in poeciliid fishes. Nat Commun 2019; 10:3335. [PMID: 31350395 PMCID: PMC6659687 DOI: 10.1038/s41467-019-11307-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 06/28/2019] [Indexed: 11/10/2022] Open
Abstract
In live-bearing animal lineages, the evolution of the placenta is predicted to create an arena for genomic conflict during pregnancy, drive patterns of male sexual selection, and increase the rate of speciation. Here we test these predictions of the viviparity driven conflict hypothesis (VDCH) in live-bearing poecilid fishes, a group showing multiple independent origins of placentation and extreme variation in male sexually selected traits. As predicted, male sexually selected traits are only gained in lineages that lack placentas; while there is little or no influence of male traits on the evolution of placentas. Both results are consistent with the mode of female provisioning governing the evolution of male attributes. Moreover, it is the presence of male sexually selected traits (pre-copulatory), rather than placentation (post-copulatory), that are associated with higher rates of speciation. These results highlight a causal interaction between female reproductive mode, male sexual selection and the rate of speciation, suggesting a role for conflict in shaping diverse aspects of organismal biology. The viviparity driven conflict hypothesis predicts the evolution of the placenta will suppress the evolution of traits associated with pre-copulatory mate choice and accelerate speciation rate. Furness et al. support the former and disprove the latter predictions with comparative analyses of the poecilid fishes.
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Affiliation(s)
- Andrew I Furness
- Department of Biological and Marine Sciences, University of Hull, Cottingham Road, Hull, HU6 7RX, UK.
| | - Bart J A Pollux
- Experimental Zoology Group, Wageningen University, 6708 WD, Wageningen, The Netherlands
| | - Robert W Meredith
- Department of Biology, Montclair State University, Montclair, NJ, 07043, USA
| | - Mark S Springer
- Department of Biology, University of California, Riverside, CA, 92521, USA
| | - David N Reznick
- Department of Biology, University of California, Riverside, CA, 92521, USA.
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10
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Mateos M, Domínguez‐Domínguez O, Varela‐Romero A. A multilocus phylogeny of the fish genus Poeciliopsis: Solving taxonomic uncertainties and preliminary evidence of reticulation. Ecol Evol 2019; 9:1845-1857. [PMID: 30847076 PMCID: PMC6392363 DOI: 10.1002/ece3.4874] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 11/06/2018] [Accepted: 12/04/2018] [Indexed: 12/15/2022] Open
Abstract
The fish genus Poeciliopsis constitutes a valuable research system for evolutionary ecology, whose phylogenetic relationships have not been fully elucidated. We conducted a multilocus phylogenetic study of the genus based on seven nuclear and two mitochondrial loci with a thorough set of analytical approaches, that is, concatenated (also known as super-matrix), species trees, and phylogenetic networks. Although several relationships remain unresolved, the overall results uncovered phylogenetic affinities among several members of this genus. A population previously considered of undetermined taxonomic status could be unequivocally assigned to P. scarlli; revealing a relatively recent dispersal event across the Trans-Mexican Volcanic Belt (TMVB) or Pacific Ocean, which constitute a strong barrier to north-south dispersal of many terrestrial and freshwater taxa. The closest relatives of P. balsas, a species distributed south of the TMVB, are distributed in the north; representing an additional north-south split in the genus. An undescribed species of Poeciliopsis, with a highly restricted distribution (i.e., a short stretch of the Rio Concepcion; just south of the US-Mexico border), falls within the Leptorhaphis species complex. Our results are inconsistent with the hypothesis that this species originated by "breakdown" of an asexual hybrid lineage. On the other hand, network analyses suggest one or more possible cases of reticulation within the genus that require further evaluation with genome-wide marker representation and additional analytical tools. The most strongly supported case of reticulation occurred within the subgenus Aulophallus (restricted to Central America), and implies a hybrid origin for P. retropinna (i.e., between P. paucimaculata and P. elongata). We consider that P. balsas and P. new species are of conservation concern.
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Affiliation(s)
- Mariana Mateos
- Department of Wildlife and Fisheries SciencesTexas A&M UniversityCollege StationTexas
| | - Omar Domínguez‐Domínguez
- Laboratorio de Biología Acuática, Facultad de BiologíaUniversidad Michoacana de San Nicolás de HidalgoMoreliaMichoacánMexico
| | - Alejandro Varela‐Romero
- Departamento de Investigaciones Científicas y TecnológicasUniversidad de SonoraHermosilloSonoraMexico
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11
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Cailleau A, Grimanelli D, Blanchet E, Cheptou PO, Lenormand T. Dividing a Maternal Pie among Half-Sibs: Genetic Conflicts and the Control of Resource Allocation to Seeds in Maize. Am Nat 2018; 192:577-592. [PMID: 30332585 DOI: 10.1086/699653] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Resource allocation to offspring is the battleground for various intrafamilial conflicts. Understanding these conflicts requires knowledge of how the different actors (mother, siblings with different paternal genotypes) influence resource allocation. In angiosperms, allocation of resources to seeds happens postfertilization, and the paternally inherited genome in offspring can therefore influence resource allocation. However, the precise mode of resource allocation-and, in particular, the occurrence of sibling rivalry-has rarely been investigated in plants. In this article, we develop a new method for analyzing the resource-allocation traits of the different actors (maternal sporophyte and half-sibs) using data obtained from a large-scale diallel cross experiment in maize involving mixed hand pollination and color markers to assess seed weight of known paternity. We found strong evidence for the occurrence of sibling rivalry: resources invested in an ear were allocated competitively, and offspring with different paternal genotypes aggressively competed for these resources, entailing a measurable direct cost to the mother. We also show how resource allocation can be described for each genotype by two maternal traits (source effect, average sink responsiveness) and two offspring traits (ability to attract maternal resources, competitive ability toward siblings). We will discuss how these findings help to understand how genetic conflicts shape resource-allocation traits in angiosperms.
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12
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Abstract
Patrick Abbot & Antonis Rokas introduce the biology of pregnancy in mammals.
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Affiliation(s)
- Patrick Abbot
- Department of Biological Sciences, Vanderbilt University, VU Station B #351634, Nashville, TN 37235, USA.
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, VU Station B #351634, Nashville, TN 37235, USA.
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13
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Morrison KR, Ngo V, Cardullo RA, Reznick DN. How fish eggs are preadapted for the evolution of matrotrophy. Proc Biol Sci 2018; 284:rspb.2017.1342. [PMID: 29167357 DOI: 10.1098/rspb.2017.1342] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 10/19/2017] [Indexed: 11/12/2022] Open
Abstract
Teleost fishes evolved livebearing via egg retention 14 times. Matrotrophy has evolved within 12 of those lineages. By contrast, squamate reptiles evolved livebearing over 115 times, but only two to four of those lineages are known to have evolved matrotrophy. Is the discrepancy between these organisms in the probability of this transition caused by differences in their eggs? We show that the eggs of oviparous species in the superorder Atherinomorpha can acquire small organic molecules from their surrounding environment against a concentration gradient via mechanisms of active transport. Uptake rates were inhibited by competing radiolabelled amino acids against unlabelled versions of themselves. Transport was non-specific as uptake rates were similar for l-leucine and its biologically uncommon enantiomer d-leucine. Eggs are also capable of transporting larger microspheres across the membrane, but transport is inhibited at temperatures below 4°C, suggesting active transport occurs via pinocytosis. Conflict theory predicts that the ability of the egg to acquire maternal resources will facilitate the embryo-parent arms race that leads to the evolution of matrotrophy following the transition to livebearing. The shelled eggs of amniotes lack such access to maternal resources when retained in the evolution of viviparity.
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Affiliation(s)
- Keenan R Morrison
- Department of Biology, University of California, Riverside, CA 92507, USA
| | - Vyvian Ngo
- Department of Biology, University of California, Riverside, CA 92507, USA
| | - Richard A Cardullo
- Department of Biology, University of California, Riverside, CA 92507, USA
| | - David N Reznick
- Department of Biology, University of California, Riverside, CA 92507, USA
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