1
|
Spoelhof JP, Keeffe R, McDaniel SF. Does reproductive assurance explain the incidence of polyploidy in plants and animals? THE NEW PHYTOLOGIST 2020; 227:14-21. [PMID: 31883115 DOI: 10.1111/nph.16396] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 12/17/2019] [Indexed: 06/10/2023]
Affiliation(s)
- Jonathan P Spoelhof
- Florida Museum of Natural History, University of Florida, Gainesville, FL, 32611, USA
- Department of Biology, University of Florida, Gainesville, FL, 32611, USA
| | - Rachel Keeffe
- Florida Museum of Natural History, University of Florida, Gainesville, FL, 32611, USA
- Department of Biology, University of Florida, Gainesville, FL, 32611, USA
| | - Stuart F McDaniel
- Department of Biology, University of Florida, Gainesville, FL, 32611, USA
| |
Collapse
|
2
|
Perea S, Sousa‐Santos C, Robalo J, Doadrio I. Multilocus phylogeny and systematics of Iberian endemicSqualius(Actinopterygii, Leuciscidae). ZOOL SCR 2020. [DOI: 10.1111/zsc.12420] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Silvia Perea
- Department of Biodiversity and Evolutionary Biology Museo Nacional de Ciencias Naturales - CSIC Madrid Spain
| | - Carla Sousa‐Santos
- MARE – Marine and Environmental Sciences Centre ISPA‐Instituto Universitário Lisbon Portugal
| | - Joana Robalo
- MARE – Marine and Environmental Sciences Centre ISPA‐Instituto Universitário Lisbon Portugal
| | - Ignacio Doadrio
- Department of Biodiversity and Evolutionary Biology Museo Nacional de Ciencias Naturales - CSIC Madrid Spain
| |
Collapse
|
3
|
Sousa-Santos C, Jesus TF, Fernandes C, Robalo JI, Coelho MM. Fish diversification at the pace of geomorphological changes: evolutionary history of western Iberian Leuciscinae (Teleostei: Leuciscidae) inferred from multilocus sequence data. Mol Phylogenet Evol 2018; 133:263-285. [PMID: 30583043 DOI: 10.1016/j.ympev.2018.12.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 12/12/2018] [Accepted: 12/15/2018] [Indexed: 01/05/2023]
Abstract
The evolutionary history of western Iberian Leuciscinae, obligatory freshwater fish, is directly linked to the evolution of the hydrographic network of the Iberian Peninsula after its isolation from the rest of Europe, which involved dramatic rearrangements such as the transition from endorheic lakes to open basins draining to the Atlantic. Previous phylogenetic research on western Iberian leuciscines, using mainly mitochondrial DNA and more recently one or two nuclear genes, has found contradictory results and there remain many unresolved issues regarding species relationships, taxonomy, and evolutionary history. Moreover, there is a lack of integration between phylogenetic and divergence time estimates and information on the timing of geomorphological changes and paleobasin rearrangements in the Iberian Peninsula. This study presents the first comprehensive fossil-calibrated multilocus coalescent species tree of western Iberian Leuciscinae (including 14 species of Achondrostoma, Iberochondrostoma, Pseudochondrostoma and Squalius endemic to the Iberian Peninsula, seven of which endemic to Portugal) based on seven nuclear genes, and from which we infer their biogeographic history by comparing divergence time estimates to known dated geological events. The phylogenetic pattern suggests slow-paced evolution of leuciscines during the Early-Middle Miocene endorheic phase of the main Iberian river basins, with the shift to exorheism in the late Neogene-Quaternary allowing westward dispersals that resulted in many cladogenetic events and a high rate of endemism in western Iberia. The results of this study also: (i) confirm the paraphyly of S. pyrenaicus with respect to S. carolitertii, and thus the possible presence of a new taxon in the Portuguese Tagus currently assigned to S. pyrenaicus; (ii) support the taxonomic separation of the Guadiana and Sado populations of S. pyrenaicus; (iii) show the need for further population sampling and taxonomic research to clarify the phylogenetic status of A. arcasii from the Minho basin and of the I. lusitanicum populations in the Sado and Tagus basins; and (iv) indicate that A. occidentale, I. olisiponensis and P. duriensis are the most ancient lineages within their respective genera.
Collapse
Affiliation(s)
- C Sousa-Santos
- MARE - Marine and Environmental Sciences Centre, ISPA-Instituto Universitário, Rua Jardim do Tabaco 34, 1149-041 Lisbon, Portugal.
| | - T F Jesus
- cE3c - Center for Ecology, Evolution and Environmental Changes, Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Av. Professor Egaz Moniz, 1649-028 Lisbon, Portugal(2).
| | - C Fernandes
- cE3c - Center for Ecology, Evolution and Environmental Changes, Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal.
| | - J I Robalo
- MARE - Marine and Environmental Sciences Centre, ISPA-Instituto Universitário, Rua Jardim do Tabaco 34, 1149-041 Lisbon, Portugal.
| | - M M Coelho
- cE3c - Center for Ecology, Evolution and Environmental Changes, Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal.
| |
Collapse
|
4
|
Alves MJ, Coelho MM, Collares‐Pereira MJ, Dowling TE. MATERNAL ANCESTRY OF THE
RUTILUS ALBURNOIDES
COMPLEX (TELEOSTEI, CYPRINIDAE) AS DETERMINED BY ANALYSIS OF CYTOCHROME
b
SEQUENCES. Evolution 2017; 51:1584-1592. [DOI: 10.1111/j.1558-5646.1997.tb01481.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/1997] [Accepted: 05/30/1997] [Indexed: 11/27/2022]
Affiliation(s)
- M. J. Alves
- Departamento de Zoologia e Antropologia Faculdade de Ciências, Universidade de Lisboa Campo Grande C2 ‐ Piso 3, 1700 Lisboa Portugal
| | - M. M. Coelho
- Departamento de Zoologia e Antropologia Faculdade de Ciências, Universidade de Lisboa Campo Grande C2 ‐ Piso 3, 1700 Lisboa Portugal
| | - M. J. Collares‐Pereira
- Departamento de Zoologia e Antropologia Faculdade de Ciências, Universidade de Lisboa Campo Grande C2 ‐ Piso 3, 1700 Lisboa Portugal
| | - T. E. Dowling
- Department of Biology Arizona State University Tempe Arizona 85287‐1501
| |
Collapse
|
5
|
Hybridization between Cottus gobio and Cottus poecilopus in the Odra River drainage basin (Czech Republic). Biologia (Bratisl) 2012. [DOI: 10.2478/s11756-012-0071-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
6
|
Cunha C, Doadrio I, Abrantes J, Coelho MM. The evolutionary history of the allopolyploid Squalius alburnoides (Cyprinidae) complex in the northern Iberian Peninsula. Heredity (Edinb) 2011; 106:100-12. [PMID: 20531449 PMCID: PMC3183856 DOI: 10.1038/hdy.2010.70] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Revised: 04/28/2010] [Accepted: 04/29/2010] [Indexed: 11/09/2022] Open
Abstract
Understanding the population structure, population dynamics and processes that give rise to polyploidy and helps to maintain it is central to our knowledge of the evolution of asexual vertebrates. Previous studies revealed high genetic diversity and several reproductive pathways in the southern populations of the Squalius alburnoides hybrid complex. In contrast, lower genetic variability and the associated limited chance of introducing new genetic combinations may threaten the survival of the northern Mondego populations. We analysed the genetic diversity and structure of nine populations of S. alburnoides in the Iberian Peninsula using microsatellite loci to provide further insights on the evolutionary history of this complex. Special attention was given to the less-studied northern populations (Mondego and Douro basins). Marked population structure, a high frequency of private alleles and a high diversity of some biotypes in the Douro basin indicate that some northern populations may not be at high risk of extinction, contrary to what was expected. The genetic diversity found in the northern Douro populations contradicts the general trend of remarkable genetic impoverishment northwards that occurs in other species and regions. The results indicate the possible existence of a glacial refugium in the Rabaçal River, corroborating findings in other species of this region. Historical events seem to have affected the geographical patterns of genetic variability found among and within the northern and southern populations of this complex and contributed to different patterns of genome composition. Therefore, historical events might have a major role in the long-term persistence of some polyploid hybrid taxa.
Collapse
Affiliation(s)
- C Cunha
- Faculdade de Ciências de Lisboa, Centro de Biologia Ambiental, Universidade de Lisboa, Lisbon, Portugal.
| | | | | | | |
Collapse
|
7
|
Genetic Stability of Progeny from an Artificial Allotetraploid Carp Using Sperm from Five Fish Species. Biochem Genet 2009; 47:533-9. [DOI: 10.1007/s10528-009-9259-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2008] [Accepted: 05/30/2009] [Indexed: 11/30/2022]
|
8
|
Cunha C, Bastir M, Coelho MM, Doadrio I. Body shape evolution among ploidy levels of the Squalius alburnoides hybrid complex (Teleostei, Cyprinidae). J Evol Biol 2009; 22:718-28. [PMID: 19320794 DOI: 10.1111/j.1420-9101.2009.01695.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Hybridization, ploidy level and genomic constitution may be important to respond to different environments, by producing different phenotypes and thus reducing competitive interaction. Through geometric morphometrics, we examined variation in body size and shape among biotypes of the Squalius alburnoides hybrid complex and their sperm donor (Squalius carolitertii). Results showed that S. carolitertii is significantly larger in size than the biotypes of the complex. No significant relationship was observed between ploidy and body size among S. alburnoides biotypes. Significant variation in body shape was found between S. carolitertii and S. alburnoides, and between tetraploids and the other biotypes. These differences in biotypes may reduce resource competition, highlighting the potential importance of resource availability favouring one biotype over another. In S. alburnoides, the adaptation to different trophic niches through modification of trophic morphology, body shapes, and feeding behaviour, may result from an increase in ploidy and genomic constitution. This adaptation may account also for the formation and maintenance of this nonsexual complex.
Collapse
Affiliation(s)
- C Cunha
- Departamento de Biodiversidad y Biología Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain.
| | | | | | | |
Collapse
|
9
|
Sousa-Santos C, Collares-Pereira MJ, Almada V. Reading the history of a hybrid fish complex from its molecular record. Mol Phylogenet Evol 2007; 45:981-96. [PMID: 17600731 DOI: 10.1016/j.ympev.2007.05.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2007] [Revised: 05/07/2007] [Accepted: 05/08/2007] [Indexed: 10/23/2022]
Abstract
Squalius alburnoides is a widely distributed intergeneric hybrid complex with fish of both sexes, varying ploidy levels and proportions of the parental genomes. Its dispersal routes were here delineated and framed by the reconstruction of the phylogeny and phylogeography of other Squalius with which it hybridizes, based on the available data on the paleohydrographical history of the Iberian Peninsula. Results based on sequences of cytochrome b and beta-actin genes showed that: proto-Squalius pyrenaicus originated at least five species as it dispersed throughout the Iberian Peninsula in the Mio-Pliocene; the S. alburnoides complex likely had a single origin in the bulk of Iberia, in the Upper Tagus/Guadiana area, when hydrographical rearrangements allowed the contact between its ancestors (around 700,000 years ago); interspecific crosses allowed the introgression of mitochondrial and nuclear genes of S. alburnoides in allopatric species/populations of other Squalius and vice-versa; and reconstituted S. alburnoides non-hybrid males may contribute to the replacement of the typical mtDNA of the complex (in the populations where they occur, crosses with females of other Squalius seem to have been especially frequent). A number of dispersal events and colonization routes are proposed.
Collapse
Affiliation(s)
- C Sousa-Santos
- Instituto Superior de Psicologia Aplicada, Unidade de Investigação em Eco-Etologia, Rua Jardim do Tabaco 34, 1149-041 Lisboa, Portugal.
| | | | | |
Collapse
|
10
|
Crespo-López ME, Duarte T, Dowling T, Coelho MM. Modes of reproduction of the hybridogenetic fish Squalius alburnoides in the Tejo and Guadiana rivers: An approach with microsatellites. ZOOLOGY 2006; 109:277-86. [PMID: 16989992 DOI: 10.1016/j.zool.2006.03.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Revised: 11/11/2005] [Accepted: 03/13/2006] [Indexed: 11/27/2022]
Abstract
The Squalius alburnoides complex was produced by hybridization between female S. pyrenaicus (PP genome) and an hypothetical paternal ancestor related with Anaecypris hispanica (AA genome). This study examined a diversity of mating types and found that there is the potential for considerable gene exchange among diploid, triploid and tetraploid hybrids. Using microsatellites, genomes were attributed to Squalius pyrenaicus (P) or reconstituted "nuclear non-hybrid"S. alburnoides (A), and subsequently confirmed in hybrids. Recombination of AA genomes in the "nuclear non-hybrid males" and recombination of the homogametic genomes (AA or PP) after exclusion of the heterogametic genome in triploid females (PAA) were observed by analysing parents and progeny of breeding experiments. Reproduction of tetraploids, generating a symmetric tetraploid genotype (PPAA) in the progeny, suggests a process that could potentially lead to the formation of a new bisexual species. Present results also support: (i) previously hypothesized pathways, in which PPA S. alburnoides females exclude the A genome, exhibit meiotic recombination between the P genomes and generate haploid eggs; (ii) reconstitution of the diploid maternal ancestor genome (PP) as well as of the unknown paternal ancestor (AA); (iii) the occurrence of the same genomic reproductive mechanisms when Anaecypris hispanica is involved; and (iv) the existence of an A. hispanica-like ancestor as the paternal ancestor of S. alburnoides.
Collapse
Affiliation(s)
- María E Crespo-López
- Centro de Biologia Ambiental/Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Bloco C2-3 piso, Campo Grande, 1749-016 Lisbon, Portugal.
| | | | | | | |
Collapse
|
11
|
Sousa‐Santos C, Collares‐Pereira M, Almada VC. May a hybridogenetic complex regenerate the nuclear genome of both sexes of a missing ancestor? First evidence on the occurrence of a nuclear non‐hybridSqualius alburnoides(Cyprinidae) female based on DNA sequencing. J NAT HIST 2006. [DOI: 10.1080/00222930600934111] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
12
|
Robalo JI, Sousa Santos C, Levy A, Almada VC. Molecular insights on the taxonomic position of the paternal ancestor of the Squalius alburnoides hybridogenetic complex. Mol Phylogenet Evol 2006; 39:276-81. [PMID: 16213165 DOI: 10.1016/j.ympev.2005.08.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2005] [Revised: 08/09/2005] [Accepted: 08/22/2005] [Indexed: 11/26/2022]
Affiliation(s)
- J I Robalo
- Instituto Superior de Psicologia Aplicada, Unidade de Investigação em Eco-Etologia, Rua Jardim do Tabaco 34, 1149-041 Lisbon, Portugal.
| | | | | | | |
Collapse
|
13
|
Gromicho M, Collares-Pereira MJ. Polymorphism of major ribosomal gene chromosomal sites (NOR-phenotypes) in the hybridogenetic fish Squalius alburnoides complex (Cyprinidae) assessed through crossing experiments. Genetica 2005; 122:291-302. [PMID: 15609552 DOI: 10.1007/s10709-004-1420-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Chromosomal locations of major ribosomal sites, i.e. NOR-phenotypes, were assigned in Squalius alburnoides complex using sequential chromomycin A3 (CMA3)- and silver (Ag)-staining. This hybridogenetic Iberian minnow comprises diploid, triploid and tetraploid forms that arose by interspecific hybridisation between S. pyrenaicus and an unknown species. Inheritance of NOR patterns was studied by means of crossing experiments involving most diploid-polyploid forms of the S. alburnoides complex with identified specific genotype constitution. In all the specimens studied, the NORs were localised in the short arms of submetacentric chromosomes. Although S. pyrenaicus presented only one pair of NOR-bearing chromosomes, the data from experimental crosses evidenced that S. alburnoides complex was characterised by a multiple NOR phenotype composed of one chromosome pair with stable NORs and two chromosome pairs with NOR site polymorphism of presence/absence type. These data suggest that the karyotype of the unknown parental species of the S. alburnoides complex should have a multiple NOR pattern and emphasised the role of the all-male diploid linage in the dynamics and evolutionary potential of the S. alburnoides complex allowing the preservation of the missing ancestor genome. Cross-analyses evidenced that in spite of the high polymorphic nature of NORs in this fish complex, we have no reason to reject the hypothesis that their inheritance patterns were in accordance with Mendelian segregation.
Collapse
Affiliation(s)
- Marta Gromicho
- Universidade de Lisboa, Faculdade de Ciências, Centro de Biologia Ambiental, C2-Piso 3, Campo Grande, 1749-016 Lisboa, Portugal
| | | |
Collapse
|
14
|
Pala I, Coelho MM. Contrasting views over a hybrid complex: Between speciation and evolutionary “dead-end”. Gene 2005; 347:283-94. [PMID: 15777631 DOI: 10.1016/j.gene.2004.12.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2004] [Revised: 11/19/2004] [Accepted: 12/07/2004] [Indexed: 10/25/2022]
Abstract
The Squalius alburnoides complex, of hybrid origin, comprises diploid, triploid and tetraploid forms and has a widespread distribution in the Iberian waters. The southern populations of this complex, sympatric with S. pyrenaicus, show high genetic variability, diversity of forms and reproductive modes which create pathways that may allow for the establishment of a new species in the future. Here we report a contrasting view over the S. alburnoides complex: in the Mondego River basin (northern Portugal), nuclear "non-hybrid" and tetraploid forms are absent and a clearly impoverished genetic diversity is observed, contributing to a general scarcity of possibilities of generating novel genetic material. Moreover, the bisexual species involved in the maintenance of the complex in this basin (S. carolitertii) exhibits a considerably lower genetic variability, when compared with S. pyrenaicus. The observed differences suggest that, despite being originated by similar hybridization events and maintained by analogous reproductive mechanisms, different populations of the complex were exposed to distinct evolutionary constrains, which in some cases resulted in diversification and speciation while in others led to a compromising situation in terms of evolutionary potential. Additionally, and for the first time all forms were used in the calculation of genetic distances and diversity indices, widening the possibilities of analysis of the complex by allowing the inclusion of a large part of the available data, irrespective of ploidy level.
Collapse
Affiliation(s)
- I Pala
- Centro de Biologia Ambiental, Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Bloco C2-3 piso, Campo Grande, 1749-016 Lisboa, Portugal.
| | | |
Collapse
|
15
|
Cunha C, Coelho MM, Carmona JA, Doadrio I. Phylogeographical insights into the origins of the Squalius alburnoides complex via multiple hybridization events. Mol Ecol 2004; 13:2807-17. [PMID: 15315691 DOI: 10.1111/j.1365-294x.2004.02283.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The origin, the phylogeographical structure and divergence times of hybridrogenetic Squalius alburnoides complex were analysed based on the complete mitochondrial cytochrome b gene (1140 pb). The molecular phylogenetic analyses suggest that the S. alburnoides complex has at least five asexual lineages of independent origin. The events that produced this ancestral hybridization took place over a long period of time. There have been multiple hybridization events throughout time, beginning in the upper Pliocene and probably continuing into the present. Increased humidity caused by climate changes in the Pliocene, along with tectonic lifting and vasculation of the Iberian Peninsula, led to the formation of current river drainages which, in turn, contributed to these hybridization events. We postulate that the Northwestern (Mondego and Douro) and the Southwest (Quarteira) drainages of the Iberian Peninsula delimited the border of the maternal ancestral distribution and that vicariant events led to the disappearance of the maternal ancestor in these regions, leaving today only the hybrid species. Two hypotheses have been suggested to explain the similarities between the mtDNA diversity observed in S. alburnoides and its maternal ancestor (S. pyrenaicus). The first hypothesizes that mtDNA similarity results from the recent extinction of the paternal ancestor, while the other postulates that: 'reconstituted non hybrid males' assumed the place of the extinct bisexual paternal ancestor and produced new hybridizations with S. pyrenaicus females.
Collapse
Affiliation(s)
- C Cunha
- Museo Nacional de Ciencias Naturales, CSIC, Departamento de Biodiversidad y Biología Evolutiva, C/José Gutiérrez Abascal, 2, 28006 Madrid, Spain.
| | | | | | | |
Collapse
|
16
|
Alves MJ, Gromicho M, Collares-Pereira MJ, Crespo-López E, Coelho MM. Simultaneous production of triploid and haploid eggs by triploidSqualius alburnoides(Teleostei: Cyprinidae). ACTA ACUST UNITED AC 2004; 301:552-8. [PMID: 15229865 DOI: 10.1002/jez.a.51] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The hybrid minnow Squalius alburnoides comprises diploid and polyploid forms with altered modes of reproduction. In the present paper, we report a cross where a triploid female generated both large, triploid and small, haploid eggs simultaneously, which were fertilized with S. pyrenaicus sperm. Although the large eggs were rarer (15%), they originated offspring with higher survivorship, so that tetraploids were dominant among the surviving siblings. The cross yielded apparently all female progeny. Inheritance patterns were inferred using four microsatellite markers and NORs (Nucleolus Organizer Regions) phenotypes, and suggested that haploid eggs were probably produced by an atypical hybridogenesis, in which the elimination of the unmatched genome permitted random segregation and recombination between the homospecific genomes, while the triploid eggs were clonal. The present results suggest that the occurrence of triploid unreduced eggs may be a new route for the natural tetraploidization in the complex.
Collapse
Affiliation(s)
- M Judite Alves
- Museu Bocage, Museu Nacional de História Natural, Universidade de Lisboa, Rua da Escola Politécnica 58, 1269-102 Lisbon, Portugal.
| | | | | | | | | |
Collapse
|
17
|
Alves MJ, Coelho MM, Próspero MI, Collares-Pereira MJ. Production of fertile unreduced sperm by hybrid males of the Rutilus alburnoides complex (Teleostei, cyprinidae). An alternative route to genome tetraploidization in unisexuals. Genetics 1999; 151:277-83. [PMID: 9872966 PMCID: PMC1460441 DOI: 10.1093/genetics/151.1.277] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The hybrid minnow Rutilus alburnoides comprises diploid and polyploid females and males. Previous studies revealed that diploid and triploid females exhibit altered oogenesis that does not involve random segregation and recombination of the genomes of the two ancestors, constituting unisexual lineages. In the present study, we investigated the reproductive mode of hybrid males from the Tejo basin, using experimental crosses and flow cytometric analysis of blood and sperm. The results suggest that diploid hybrids produced fertile unreduced sperm, transmitting their hybrid genome intact to offspring. Triploid hybrids also produced unreduced sperm, but it was not possible to obtain data concerning their fertility. Finally, tetraploid hybrids produced fertile diploid sperm, which exhibited Mendelian segregation. Tetraploid R. alburnoides may reestablish biparental reproduction, as individuals of both sexes with the appropriate constitution for normal meiosis (two haploid genomes from each parental species) are likely to occur in natural populations. Tetraploids probably have arisen from syngamy of diploid eggs and diploid sperm produced by diploid hybrid males. Diploid hybrid males may therefore play a significant role in the dynamics of the complex, starting the evolutionary process that may ultimately lead to a new sexually reproducing species.
Collapse
Affiliation(s)
- M J Alves
- Centro de Biologia Ambiental, Departamento de Zoologia e Antropologia, Faculdade de Ciências, Universidade de Lisboa, 1700 Lisboa, Portugal
| | | | | | | |
Collapse
|
18
|
Dowling TE, Secor ACL. THE ROLE OF HYBRIDIZATION AND INTROGRESSION IN THE DIVERSIFICATION OF ANIMALS. ACTA ACUST UNITED AC 1997. [DOI: 10.1146/annurev.ecolsys.28.1.593] [Citation(s) in RCA: 477] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Thomas E. Dowling
- Department of Biology, Arizona State University, Tempe, Arizona; 85287-1501 e-mail: ,
| | - and Carol L. Secor
- Department of Biology, Arizona State University, Tempe, Arizona; 85287-1501 e-mail: ,
| |
Collapse
|