1
|
Cama B, Heaton K, Thomas-Oates J, Schulz S, Dasmahapatra KK. Complexity of Chemical Emissions Increases Concurrently with Sexual Maturity in Heliconius Butterflies. J Chem Ecol 2024; 50:197-213. [PMID: 38478290 PMCID: PMC11233321 DOI: 10.1007/s10886-024-01484-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 02/21/2024] [Accepted: 03/03/2024] [Indexed: 07/10/2024]
Abstract
Pheromone communication is widespread among animals. Since it is often involved in mate choice, pheromone production is often tightly controlled. Although male sex pheromones (MSPs) and anti-aphrodisiacs have been studied in some Heliconius butterfly species, little is known about the factors affecting their production and release in these long-lived butterflies. Here, we investigate the effect of post-eclosion age on chemical blends from pheromone-emitting tissues in Heliconius atthis and Heliconius charithonia, exhibiting respectively free-mating and pupal-mating strategies that are hypothesised to differently affect the timing of their pheromone emissions. We focus on two different tissues: the wing androconia, responsible for MSPs used in courtship, and the genital tip, the production site for anti-aphrodisiac pheromones that affect post-mating behaviour. Gas chromatography-mass spectrometric analysis of tissue extracts from virgin males and females of both species from day 0 to 8 post-eclosion demonstrates the following. Some ubiquitous fatty acid precursors are already detectable at day 0. The complexity of the chemical blends increases with age regardless of tissue or sex. No obvious difference in the time course of blend production was evident between the two species, but female tissues in H. charithonia were more affected by age than in H. atthis. We suggest that compounds unique to male androconia and genitals and whose amount increases with age are potential candidates for future investigation into their roles as pheromones. While this analysis revealed some of the complexity in Heliconius chemical ecology, the effects of other factors, such as the time of day, remain unknown.
Collapse
Affiliation(s)
- Bruna Cama
- Department of Biology, University of York, Wentworth Way, Heslington, YO10 5DD, UK.
| | - Karl Heaton
- Department of Chemistry, University of York, Heslington, YO10 5DD, UK
| | - Jane Thomas-Oates
- Department of Chemistry, University of York, Heslington, YO10 5DD, UK
| | - Stefan Schulz
- Institute of Organic Chemistry, Technische Universität Braunschweig, Hagenring 30, Braunschweig, 38106, Germany
| | | |
Collapse
|
2
|
Rosser N, Seixas F, Queste LM, Cama B, Mori-Pezo R, Kryvokhyzha D, Nelson M, Waite-Hudson R, Goringe M, Costa M, Elias M, Mendes Eleres de Figueiredo C, Freitas AVL, Joron M, Kozak K, Lamas G, Martins ARP, McMillan WO, Ready J, Rueda-Muñoz N, Salazar C, Salazar P, Schulz S, Shirai LT, Silva-Brandão KL, Mallet J, Dasmahapatra KK. Hybrid speciation driven by multilocus introgression of ecological traits. Nature 2024; 628:811-817. [PMID: 38632397 PMCID: PMC11041799 DOI: 10.1038/s41586-024-07263-w] [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: 09/26/2023] [Accepted: 03/01/2024] [Indexed: 04/19/2024]
Abstract
Hybridization allows adaptations to be shared among lineages and may trigger the evolution of new species1,2. However, convincing examples of homoploid hybrid speciation remain rare because it is challenging to demonstrate that hybridization was crucial in generating reproductive isolation3. Here we combine population genomic analysis with quantitative trait locus mapping of species-specific traits to examine a case of hybrid speciation in Heliconius butterflies. We show that Heliconius elevatus is a hybrid species that is sympatric with both parents and has persisted as an independently evolving lineage for at least 180,000 years. This is despite pervasive and ongoing gene flow with one parent, Heliconius pardalinus, which homogenizes 99% of their genomes. The remaining 1% introgressed from the other parent, Heliconius melpomene, and is scattered widely across the H. elevatus genome in islands of divergence from H. pardalinus. These islands contain multiple traits that are under disruptive selection, including colour pattern, wing shape, host plant preference, sex pheromones and mate choice. Collectively, these traits place H. elevatus on its own adaptive peak and permit coexistence with both parents. Our results show that speciation was driven by introgression of ecological traits, and that speciation with gene flow is possible with a multilocus genetic architecture.
Collapse
Affiliation(s)
- Neil Rosser
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.
- Department of Biology, University of York, York, UK.
| | - Fernando Seixas
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | | | - Bruna Cama
- Department of Biology, University of York, York, UK
| | - Ronald Mori-Pezo
- URKU Estudios Amazónicos, Tarapoto, Perú
- Universidad Nacional Autónoma de Alto Amazona, Yurimaguas, Perú
| | - Dmytro Kryvokhyzha
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
- Department of Clinical Sciences, Lund University Diabetes Centre, Malmö, Sweden
| | | | | | - Matt Goringe
- Department of Biology, University of York, York, UK
| | | | - Marianne Elias
- Institut Systématique, Evolution, Biodiversité, UMR 7205 MNHN-CNRS-EPHE-UPMC Sorbonne Universités, Muséum National d'Histoire Naturelle, Paris, France
- Smithsonian Tropical Research Institute, Panama City, Panama
| | - Clarisse Mendes Eleres de Figueiredo
- Institute for Biological Sciences, Federal University of Pará (UFPA), Belém, Brazil
- Centre for Advanced Studies of Biodiversity (CEABIO), Belém, Brazil
| | - André Victor Lucci Freitas
- Departamento de Biologia Animal and Museu de Diversidade Biológica, Instituto de Biologia, Universidade Estadual de Campinas, São Paulo, Brazil
| | - Mathieu Joron
- Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175 CNRS, Université de Montpellier-Université Paul Valéry Montpellier-EPHE, Montpellier, France
| | - Krzysztof Kozak
- Smithsonian Tropical Research Institute, Panama City, Panama
| | - Gerardo Lamas
- Museo de Historia Natural, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | | | - W Owen McMillan
- Smithsonian Tropical Research Institute, Panama City, Panama
| | - Jonathan Ready
- Institute for Biological Sciences, Federal University of Pará (UFPA), Belém, Brazil
- Centre for Advanced Studies of Biodiversity (CEABIO), Belém, Brazil
| | - Nicol Rueda-Muñoz
- Biology Program, Faculty of Natural Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Camilo Salazar
- Biology Program, Faculty of Natural Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Patricio Salazar
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Sheffield, UK
| | - Stefan Schulz
- Institut für Organische Chemie, Technische Universität Braunschweig, Braunschweig, Germany
| | - Leila T Shirai
- Departamento de Biologia Animal and Museu de Diversidade Biológica, Instituto de Biologia, Universidade Estadual de Campinas, São Paulo, Brazil
| | - Karina L Silva-Brandão
- Leibniz Institute for the Analysis of Biodiversity Change, Museum de Natur Hamburg Zoology, Hamburg, Germany
| | - James Mallet
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.
| | - Kanchon K Dasmahapatra
- Department of Biology, University of York, York, UK
- Leverhulme Centre for Anthropocene Biodiversity, Department of Biology, University of York, York, UK
| |
Collapse
|
3
|
Frayer ME, Coughlan JM. Surprise hybrid origins of a butterfly species. Nature 2024; 628:723-724. [PMID: 38632416 DOI: 10.1038/d41586-024-00858-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
|
4
|
Page E, Queste LM, Rosser N, Salazar PA, Nadeau NJ, Mallet J, Srygley RB, McMillan WO, Dasmahapatra KK. Pervasive mimicry in flight behavior among aposematic butterflies. Proc Natl Acad Sci U S A 2024; 121:e2300886121. [PMID: 38408213 PMCID: PMC10945825 DOI: 10.1073/pnas.2300886121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 01/10/2024] [Indexed: 02/28/2024] Open
Abstract
Flight was a key innovation in the adaptive radiation of insects. However, it is a complex trait influenced by a large number of interacting biotic and abiotic factors, making it difficult to unravel the evolutionary drivers. We investigate flight patterns in neotropical heliconiine butterflies, well known for mimicry of their aposematic wing color patterns. We quantify the flight patterns (wing beat frequency and wing angles) of 351 individuals representing 29 heliconiine and 9 ithomiine species belonging to ten color pattern mimicry groupings. For wing beat frequency and up wing angles, we show that heliconiine species group by color pattern mimicry affiliation. Convergence of down wing angles to mimicry groupings is less pronounced, indicating that distinct components of flight are under different selection pressures and constraints. The flight characteristics of the Tiger mimicry group are particularly divergent due to convergence with distantly related ithomiine species. Predator-driven selection for mimicry also explained variation in flight among subspecies, indicating that this convergence can occur over relatively short evolutionary timescales. Our results suggest that the flight convergence is driven by aposematic signaling rather than shared habitat between comimics. We demonstrate that behavioral mimicry can occur between lineages that have separated over evolutionary timescales ranging from <0.5 to 70 My.
Collapse
Affiliation(s)
- Edward Page
- Department of Biology, University of York, HeslingtonYO10 5DD, United Kingdom
| | - Lucie M. Queste
- Department of Biology, University of York, HeslingtonYO10 5DD, United Kingdom
- Division of Evolutionary Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried82152, Germany
| | - Neil Rosser
- Department of Biology, University of York, HeslingtonYO10 5DD, United Kingdom
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA02138
| | - Patricio A. Salazar
- Ecology and Evolutionary Biology, School of Biosciences, The University of Sheffield, SheffieldS10 2TN, United Kingdom
- Tree of Life Programme, Wellcome Sanger Institute, Hinxton, CambridgeCB10 1SA, United Kingdom
| | - Nicola J. Nadeau
- Ecology and Evolutionary Biology, School of Biosciences, The University of Sheffield, SheffieldS10 2TN, United Kingdom
| | - James Mallet
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA02138
| | - Robert B. Srygley
- Smithsonian Tropical Research Institute, Apartado, Panamá0843-03092, Republic of Panama
- Pest Management Research Unit, Agricultural Research Service, United States Department of Agriculture, Sidney, MT59270
| | - W. Owen McMillan
- Smithsonian Tropical Research Institute, Apartado, Panamá0843-03092, Republic of Panama
| | | |
Collapse
|
5
|
Thawornwattana Y, Seixas F, Yang Z, Mallet J. Major patterns in the introgression history of Heliconius butterflies. eLife 2023; 12:RP90656. [PMID: 38108819 PMCID: PMC10727504 DOI: 10.7554/elife.90656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2023] Open
Abstract
Gene flow between species, although usually deleterious, is an important evolutionary process that can facilitate adaptation and lead to species diversification. It also makes estimation of species relationships difficult. Here, we use the full-likelihood multispecies coalescent (MSC) approach to estimate species phylogeny and major introgression events in Heliconius butterflies from whole-genome sequence data. We obtain a robust estimate of species branching order among major clades in the genus, including the 'melpomene-silvaniform' group, which shows extensive historical and ongoing gene flow. We obtain chromosome-level estimates of key parameters in the species phylogeny, including species divergence times, present-day and ancestral population sizes, as well as the direction, timing, and intensity of gene flow. Our analysis leads to a phylogeny with introgression events that differ from those obtained in previous studies. We find that Heliconius aoede most likely represents the earliest-branching lineage of the genus and that 'silvaniform' species are paraphyletic within the melpomene-silvaniform group. Our phylogeny provides new, parsimonious histories for the origins of key traits in Heliconius, including pollen feeding and an inversion involved in wing pattern mimicry. Our results demonstrate the power and feasibility of the full-likelihood MSC approach for estimating species phylogeny and key population parameters despite extensive gene flow. The methods used here should be useful for analysis of other difficult species groups with high rates of introgression.
Collapse
Affiliation(s)
| | - Fernando Seixas
- Department of Organismic and Evolutionary Biology, Harvard UniversityCambridgeUnited States
| | - Ziheng Yang
- Department of Genetics, Evolution and Environment, University College LondonLondonUnited Kingdom
| | - James Mallet
- Department of Organismic and Evolutionary Biology, Harvard UniversityCambridgeUnited States
| |
Collapse
|
6
|
Xiong T, Mallet J. On the impermanence of species: The collapse of genetic incompatibilities in hybridizing populations. Evolution 2022; 76:2498-2512. [PMID: 36097352 PMCID: PMC9827863 DOI: 10.1111/evo.14626] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 07/23/2022] [Indexed: 01/22/2023]
Abstract
Species pairs often become genetically incompatible during divergence, which is an important source of reproductive isolation. An idealized picture is often painted where incompatibility alleles accumulate and fix between diverging species. However, recent studies have shown both that incompatibilities can collapse with ongoing hybridization, and that incompatibility loci can be polymorphic within species. This paper suggests some general rules for the behavior of incompatibilities under hybridization. In particular, we argue that redundancy of genetic pathways can strongly affect the dynamics of intrinsic incompatibilities. Since fitness in genetically redundant systems is unaffected by introducing a few foreign alleles, higher redundancy decreases the stability of incompatibilities during hybridization, but also increases tolerance of incompatibility polymorphism within species. We use simulations and theories to show that this principle leads to two types of collapse: in redundant systems, exemplified by classical Dobzhansky-Muller incompatibilities, collapse is continuous and approaches a quasi-neutral polymorphism between broadly sympatric species, often as a result of isolation-by-distance. In nonredundant systems, exemplified by co-evolution among genetic elements, incompatibilities are often stable, but can collapse abruptly with spatial traveling waves. As both types are common, the proposed principle may be useful in understanding the abundance of genetic incompatibilities in natural populations.
Collapse
Affiliation(s)
- Tianzhu Xiong
- Department of Organismic and Evolutionary BiologyHarvard UniversityCambridgeMA02138USA
| | - James Mallet
- Department of Organismic and Evolutionary BiologyHarvard UniversityCambridgeMA02138USA
| |
Collapse
|
7
|
Giles‐Pérez GI, Aguirre‐Planter E, Eguiarte LE, Jaramillo‐Correa JP. Demographic modelling helps track the rapid and recent divergence of a conifer species pair from Central Mexico. Mol Ecol 2022; 31:5074-5088. [PMID: 35951172 PMCID: PMC9804182 DOI: 10.1111/mec.16646] [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] [Received: 04/29/2021] [Revised: 07/26/2022] [Accepted: 07/28/2022] [Indexed: 01/05/2023]
Abstract
Secondary contact of recently diverged species may have several outcomes, ranging from rampant hybridization to reinforced reproductive isolation. In plants, selfing tolerance and disjunct reproductive phenology may lead to reproductive isolation at contact zones. However, they may also evolve under both allopatric or parapatric frameworks and originate from adaptive and/or neutral forces. Inferring the historical demography of diverging taxa is thus a crucial step to identify factors that may have led to putative reproductive isolation. We explored various competing demographypotheses to account for the rapid divergence of a fir species complex (Abies flinckii-A. religiosa) distributed in "sky-islands" across central Mexico (i.e., along the Trans-Mexican Volcanic Belt; TMVB). Despite co-occurring in two independent sympatric regions (west and centre), these taxa rarely interbreed because of disjunct reproductive phenologies. We genotyped 1147 single nucleotide polymorphisms, generated by GBS (genotyping by sequencing), across 23 populations, and compared multiple scenarios based on the geological history of the TMVB. The best-fitting model revealed one of the most rapid and complete speciation cases for a conifer species-pair, dating back to ~1.2 million years ago. Coupled with the lack of support for stepwise colonization, our coalescent inferences point to an early cessation of interspecific gene flow under parapatric speciation; ancestral gene flow during divergence was asymmetrical (mostly from western firs into A. religiosa) and exclusive to the most ancient (i.e., central) contact zone. Factors promoting rapid reproductive isolation should be explored in other slowly evolving species complexes as they may account for the large tropical and subtropical diversity.
Collapse
Affiliation(s)
- Gustavo I. Giles‐Pérez
- Programa de Doctorado en Ciencias BiomédicasUniversidad Nacional Autónoma de MéxicoCDMXMexico,Departamento de Ecología EvolutivaInstituto de Ecología, Universidad Nacional Autónoma de MéxicoCDMXMexico
| | - Erika Aguirre‐Planter
- Departamento de Ecología EvolutivaInstituto de Ecología, Universidad Nacional Autónoma de MéxicoCDMXMexico
| | - Luis E. Eguiarte
- Departamento de Ecología EvolutivaInstituto de Ecología, Universidad Nacional Autónoma de MéxicoCDMXMexico
| | | |
Collapse
|
8
|
Cama B, Ehlers S, Szczerbowski D, Thomas-Oates J, Jiggins CD, Schulz S, McMillan WO, Dasmahapatra KK. Exploitation of an ancestral pheromone biosynthetic pathway contributes to diversification in Heliconius butterflies. Proc Biol Sci 2022; 289:20220474. [PMID: 35892212 PMCID: PMC9326301 DOI: 10.1098/rspb.2022.0474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
During courtship, male butterflies of many species produce androconial secretions containing male sex pheromones (MSPs) that communicate species identity and affect female choice. MSPs are thus likely candidates as reproductive barriers, yet their role in speciation remains poorly studied. Although Heliconius butterflies are a model system in speciation, their MSPs have not been investigated from a macroevolutionary perspective. We use GC/MS to characterize male androconial secretions in 33 of the 69 species in the Heliconiini tribe. We found these blends to be species-specific, consistent with a role in reproductive isolation. We detected a burst in blend diversification rate at the most speciose genus, Heliconius; a consequence of Heliconius and Eueides species using a fatty acid (FA) metabolic pathway to unlock more complex blends than basal Heliconiini species, whose secretions are dominated by plant-like metabolites. A comparison of 10 sister species pairs demonstrates a striking positive correlation between blend dissimilarity and range overlap, consistent with character displacement or reinforcement in sympatry. These results demonstrate for the first time that MSP diversification can promote reproductive isolation across this group of butterflies, showcasing how implementation of an ancestral trait, the co-option of the FA metabolic pathway for pheromone production, can facilitate rapid speciation.
Collapse
Affiliation(s)
- Bruna Cama
- Department of Biology, University of York, Heslington YO10 5DD, UK
| | - Stephanie Ehlers
- Institute of Organic Chemistry, Technische Universität Braunschweig, Hagenring 30, Braunschweig 38106, Germany
| | - Daiane Szczerbowski
- Institute of Organic Chemistry, Technische Universität Braunschweig, Hagenring 30, Braunschweig 38106, Germany
| | - Jane Thomas-Oates
- Department of Chemistry, University of York, Heslington YO10 5DD, UK
| | - Chris D. Jiggins
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Stefan Schulz
- Institute of Organic Chemistry, Technische Universität Braunschweig, Hagenring 30, Braunschweig 38106, Germany
| | | | | |
Collapse
|
9
|
Szczerbowski D, Ehlers S, Darragh K, Jiggins C, Schulz S. Head and Tail Oxidized Terpenoid Esters from Androconia of Heliconius erato Butterflies. JOURNAL OF NATURAL PRODUCTS 2022; 85:1428-1435. [PMID: 35587731 DOI: 10.1021/acs.jnatprod.2c00300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Heliconius erato is a neotropical butterfly species that is part of a complex mimicry ring, with colorful wing patterns. For intraspecific communication, males use pheromones that are released from two different scent-emitting structures. Scent glands located near the abdominal claspers of males, containing antiaphrodisiac pheromones, release a highly complex mixture of compounds that is transferred to females during mating, rendering them unattractive to other males. On the other hand, androconia, scent-emitting scale areas on the wings of male butterflies, release a structurally more restricted set of compounds that likely serves an aphrodisiac role. We report here on two structurally related compounds that are the major androconial constituents, produced in high amounts and are not volatile due to their high molecular mass. Their structures were established by extensive analysis of mass, infrared, and NMR spectra, as well as microderivatization reactions of the natural extract. After establishing synthetic access, the compounds were unequivocally identified as two unusual head and tail oxidized terpenoids, (4E,8E,12E)-4,8,12-trimethyl-16-oxoheptadeca-4,8,12-trien-1-yl oleate (1) and stearate (2). Although behavioral assays are necessary to fully comprehend their role in the chemical communication of the species, hypotheses for their use by the butterflies are also discussed.
Collapse
Affiliation(s)
- Daiane Szczerbowski
- Institute of Organic Chemistry, Technische Universität Braunschweig, 38106 Braunschweig Germany
| | - Stephanie Ehlers
- Institute of Organic Chemistry, Technische Universität Braunschweig, 38106 Braunschweig Germany
| | - Kathy Darragh
- Department of Evolution and Ecology, University of California, Davis, California 95616, United States
| | - Chris Jiggins
- Department of Zoology, University of Cambridge, Downing Street, CB2 3EJ, Cambridge, United Kingdom
| | - Stefan Schulz
- Institute of Organic Chemistry, Technische Universität Braunschweig, 38106 Braunschweig Germany
| |
Collapse
|
10
|
Abstract
Alleles that introgress between species can influence the evolutionary and ecological fate of species exposed to novel environments. Hybrid offspring of different species are often unfit, and yet it has long been argued that introgression can be a potent force in evolution, especially in plants. Over the last two decades, genomic data have increasingly provided evidence that introgression is a critically important source of genetic variation and that this additional variation can be useful in adaptive evolution of both animals and plants. Here, we review factors that influence the probability that foreign genetic variants provide long-term benefits (so-called adaptive introgression) and discuss their potential benefits. We find that introgression plays an important role in adaptive evolution, particularly when a species is far from its fitness optimum, such as when they expand their range or are subject to changing environments.
Collapse
Affiliation(s)
- Nathaniel B Edelman
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA; .,Current affiliation: Yale Institute for Biospheric Studies and Yale School of the Environment, Yale University, New Haven, Connecticut 06511, USA;
| | - James Mallet
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA;
| |
Collapse
|
11
|
Rosser N, Edelman NB, Queste LM, Nelson M, Seixas F, Dasmahapatra KK, Mallet J. Complex basis of hybrid female sterility and Haldane's rule in Heliconius butterflies: Z-linkage and epistasis. Mol Ecol 2021; 31:959-977. [PMID: 34779079 DOI: 10.1111/mec.16272] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Revised: 09/14/2021] [Accepted: 09/27/2021] [Indexed: 12/19/2022]
Abstract
Hybrids between species are often sterile or inviable. Hybrid unfitness usually evolves first in the heterogametic sex-a pattern known as Haldane's rule. The genetics of Haldane's rule have been extensively studied in species where the male is the heterogametic (XX/XY) sex, but its basis in taxa where the female is heterogametic (ZW/ZZ), such as Lepidoptera and birds, is largely unknown. Here, we analyse a new case of female hybrid sterility between geographic subspecies of Heliconius pardalinus. The two subspecies mate freely in captivity, but female F1 hybrids in both directions of cross are sterile. Sterility is due to arrested development of oocytes after they become differentiated from nurse cells, but before yolk deposition. We backcrossed fertile male F1 hybrids to parental females and mapped quantitative trait loci (QTLs) for female sterility. We also identified genes differentially expressed in the ovary as a function of oocyte development. The Z chromosome has a major effect, similar to the 'large X effect' in Drosophila, with strong epistatic interactions between loci at either end of the Z chromosome, and between the Z chromosome and autosomal loci on chromosomes 8 and 20. By intersecting the list of genes within these QTLs with those differentially expressed in sterile and fertile hybrids, we identified three candidate genes with relevant phenotypes. This study is the first to characterize hybrid sterility using genome mapping in the Lepidoptera and shows that it is produced by multiple complex epistatic interactions often involving the sex chromosome, as predicted by the dominance theory of Haldane's rule.
Collapse
Affiliation(s)
- Neil Rosser
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA.,Department of Biology, University of York, York, UK
| | - Nathaniel B Edelman
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA.,Yale Institute for Biospheric Studies, Yale University, New Haven, Connecticut, USA.,Yale School for the Environment, Yale University, New Haven, Connecticut, USA
| | | | | | - Fernando Seixas
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| | | | - James Mallet
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| |
Collapse
|
12
|
Bennett KFP, Lim HC, Braun MJ. Sexual selection and introgression in avian hybrid zones: Spotlight on Manacus. Integr Comp Biol 2021; 61:1291-1309. [PMID: 34128981 DOI: 10.1093/icb/icab135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Hybrid zones offer a window into the processes and outcomes of evolution, from species formation or fusion to genomic underpinnings of specific traits and isolating mechanisms. Sexual selection is believed to be an important factor in speciation processes, and hybrid zones present special opportunities to probe its impact. The manakins (Aves, Pipridae) are a promising group in which to study the interplay of sexual selection and natural hybridization: they show substantial variation across the family in the strength of sexual selection they experience, they readily hybridize within and between genera, and they appear to have formed hybrid species, a rare event in birds. A hybrid zone between two manakins in the genus Manacus is unusual in that plumage and behavioral traits of one species have introgressed asymmetrically into populations of the second species through positive sexual selection, then apparently stalled at a river barrier. This is one of a handful of documented examples of asymmetric sexual trait introgression with a known selective mechanism. It offers opportunities to examine reproductive isolation, introgression, plumage color evolution, and natural factors enhancing or constraining the effects of sexual selection in real time. Here, we review previous work in this system, propose new hypotheses for observed patterns, and recommend approaches to test them.
Collapse
Affiliation(s)
- Kevin F P Bennett
- Behavior, Ecology, Evolution, and Systematics Program, University of Maryland, College Park, MD, USA.,Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
| | - Haw Chuan Lim
- Department of Biology, George Mason University, Manassas, VA, USA.,Center for Conservation Genomics, Smithsonian Conservation Biology Institute, Washington, DC, USA
| | - Michael J Braun
- Behavior, Ecology, Evolution, and Systematics Program, University of Maryland, College Park, MD, USA.,Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
| |
Collapse
|
13
|
Seixas FA, Edelman NB, Mallet J. Synteny-Based Genome Assembly for 16 Species of Heliconius Butterflies, and an Assessment of Structural Variation across the Genus. Genome Biol Evol 2021; 13:6207971. [PMID: 33792688 PMCID: PMC8290116 DOI: 10.1093/gbe/evab069] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2021] [Indexed: 12/11/2022] Open
Abstract
Heliconius butterflies (Lepidoptera: Nymphalidae) are a group of 48 neotropical species widely studied in evolutionary research. Despite the wealth of genomic data generated in past years, chromosomal level genome assemblies currently exist for only two species, Heliconius melpomene and Heliconius erato, each a representative of one of the two major clades of the genus. Here, we use these reference genomes to improve the contiguity of previously published draft genome assemblies of 16 Heliconius species. Using a reference-assisted scaffolding approach, we place and order the scaffolds of these genomes onto chromosomes, resulting in 95.7-99.9% of their genomes anchored to chromosomes. Genome sizes are somewhat variable among species (270-422 Mb) and in one small group of species (Heliconius hecale, Heliconius elevatus, and Heliconius pardalinus) expansions in genome size are driven mainly by repetitive sequences that map to four small regions in the H. melpomene reference genome. Genes from these repeat regions show an increase in exon copy number, an absence of internal stop codons, evidence of constraint on nonsynonymous changes, and increased expression, all of which suggest that at least some of the extra copies are functional. Finally, we conducted a systematic search for inversions and identified five moderately large inversions fixed between the two major Heliconius clades. We infer that one of these inversions was transferred by introgression between the lineages leading to the erato/sara and burneyi/doris clades. These reference-guided assemblies represent a major improvement in Heliconius genomic resources that enable further genetic and evolutionary discoveries in this genus.
Collapse
Affiliation(s)
- Fernando A Seixas
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Nathaniel B Edelman
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA.,Yale Institute for Biospheric Studies, Yale University, New Haven, Connecticut, USA
| | - James Mallet
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| |
Collapse
|
14
|
Mallet J. Alternative views of biological species: reproductively isolated units or genotypic clusters? Natl Sci Rev 2020; 7:1401-1407. [PMID: 34692169 PMCID: PMC8288880 DOI: 10.1093/nsr/nwaa116] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- James Mallet
- Department of Organismic and Evolutionary Biology, Harvard University, USA
| |
Collapse
|
15
|
Blanckaert A, Bank C, Hermisson J. The limits to parapatric speciation 3: evolution of strong reproductive isolation in presence of gene flow despite limited ecological differentiation. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190532. [PMID: 32654650 PMCID: PMC7423268 DOI: 10.1098/rstb.2019.0532] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Gene flow tends to impede the accumulation of genetic divergence. Here, we determine the limits for the evolution of postzygotic reproductive isolation in a model of two populations that are connected by gene flow. We consider two selective mechanisms for the creation and maintenance of a genetic barrier: local adaptation leads to divergence among incipient species due to selection against migrants, and Dobzhansky–Muller incompatibilities (DMIs) reinforce the genetic barrier through selection against hybrids. In particular, we are interested in the maximum strength of the barrier under a limited amount of local adaptation, a challenge that many incipient species may initially face. We first confirm that with classical two-locus DMIs, the maximum amount of local adaptation is indeed a limit to the strength of a genetic barrier. However, with three or more loci and cryptic epistasis, this limit holds no longer. In particular, we identify a minimal configuration of three epistatically interacting mutations that is sufficient to confer strong reproductive isolation. This article is part of the theme issue ‘Towards the completion of speciation: the evolution of reproductive isolation beyond the first barriers’.
Collapse
Affiliation(s)
- Alexandre Blanckaert
- Department of Mathematics, University of Vienna, 1090 Vienna, Austria.,Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
| | - Claudia Bank
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
| | - Joachim Hermisson
- Department of Mathematics, University of Vienna, 1090 Vienna, Austria.,Mathematics and Biosciences Group, Max Perutz Lab, 1030 Vienna, Austria
| |
Collapse
|