Detection of Cryptic Sex in Automictic Populations: Theoretical Expectations and a Case Study in Cataglyphis Desert Ants

Reproductive strategies are diverse and a whole continuum of mixed systems lies between strict sexuality and strict clonality (apomixis), including automixis, a parthenogenetic mode of reproduction involving a meiosis and increasing homozygosity over generations. These various systems impact the genetic structure of populations, which can therefore be used to infer reproductive strategies in natural populations. Here, we first develop a mathematical model, validated by simulations, to predict heterozygosity and inbreeding in mixed sexual-automictic populations. It highlights the predominant role of the rate of heterozygosity loss experienced during automixis (γ), which is locus dependent. When γ is low, mixed populations behave like purely sexual ones until sex becomes rare. In contrast, when γ is high, the erosion of genetic diversity is tightly correlated to the rate of sex, so that the individual inbreeding coefficient can inform on the ratio of sexual/asexual reproduction. In the second part of this study, we used our model to test the presence of cryptic sex in a hybridogenetic Cataglyphis ant where new queens are produced parthenogenetically, leaving males with an apparent null fitness while they are essential to colony development as sperm is required to produce workers. Occasional sexual production of queens could resolve this paradox by providing males some fertile progeny. To determine whether this occurs in natural populations, we simulated genotypic datasets in a population under various regimes of sexual vs. asexual reproduction for queen production and compared the distribution of inbreeding, expected heterozygosity and inter-individual relatedness coefficients with those observed in a natural population of Cataglyphis mauritanica using microsatellites. Our simulations show that the distribution of inter-individual relatedness coefficients was particularly informative to assess the relative rate of sexual/asexual reproduction, and our dataset was compatible with pure parthenogenesis but also with up to 2% sexual reproduction. Our approach, implemented in an R script, should be useful to assess reproductive strategies in other biological models.

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Individual growth of Heleobia piscium in natural populations (Gastropoda: Cochliopidae) from the multiple use natural Reserve Isla Martin Garcia, Buenos Aires, Argentina

Brazilian Journal of Biology ◽

10.1590/s1519-69842008000300020 ◽

2008 ◽

Vol 68 (3) ◽

pp. 617-621 ◽

Cited By ~ 5

Author(s):

SM. Martin

Keyword(s):

Buenos Aires ◽

Natural Populations ◽

Dynamic Structure ◽

Reproductive Period ◽

Individual Growth ◽

Growth Equation ◽

Multiple Use ◽

Natural Reserve ◽

Drainage Channels ◽

The Individual

The present work analyses the individual growth of Heleobia piscium in natural conditions in coastal drainage channels of the Multiple Use Natural Reserve Isla Martín García, Buenos Aires, Argentina. Isla Martín García is located in the Upper Río de la Plata, to the south of the mouth of the Uruguay river (34° 11' 25" S and 58° 15' 38" W). Monthly collections were made from July 2005 to July 2006 in the eastern part of the island (Arena Beach). The population of H. piscium showed a complex and dynamic structure of sizes during a long period of the annual cycle. Two cohorts could be detected. The Bertalanffy growth equation was: Lt = 6 (1-e -1.85 (t+0.38)) and Lt = 3.9 (1-e -0.19 (t+4.84)) for cohorts 1 and 2, respectively. The pattern of population growth displayed a staggered model, where the greatest growth is observed during the summer. The reproductive period occurred during six months, from the beginning of summer to middle of fall. Based on only one reproductive effort, this pattern is not similar to that of other cogeneric species already studied.

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The Evolutionary Dynamics of Genetic Incompatibilities Introduced by Duplicated Genes in Arabidopsis thaliana

Molecular Biology and Evolution ◽

10.1093/molbev/msaa306 ◽

2020 ◽

Author(s):

Wen-Biao Jiao ◽

Vipul Patel ◽

Jonas Klasen ◽

Fang Liu ◽

Petra Pecinkova ◽

...

Keyword(s):

Evolutionary Dynamics ◽

Natural Populations ◽

Population History ◽

Duplicated Genes ◽

Genetic Incompatibility ◽

Additional Gene ◽

Genomic Changes ◽

Gene Copies ◽

Geographic Origins ◽

The Individual

Abstract Although gene duplications provide genetic backup and allow genomic changes under relaxed selection, they may potentially limit gene flow. When different copies of a duplicated gene are pseudofunctionalized in different genotypes, genetic incompatibilities can arise in their hybrid offspring. Although such cases have been reported after manual crosses, it remains unclear whether they occur in nature and how they affect natural populations. Here, we identified four duplicated-gene based incompatibilities including one previously not reported within an artificial Arabidopsis intercross population. Unexpectedly, however, for each of the genetic incompatibilities we also identified the incompatible alleles in natural populations based on the genomes of 1,135 Arabidopsis accessions published by the 1001 Genomes Project. Using the presence of incompatible allele combinations as phenotypes for GWAS, we mapped genomic regions that included additional gene copies which likely rescue the genetic incompatibility. Reconstructing the geographic origins and evolutionary trajectories of the individual alleles suggested that incompatible alleles frequently coexist, even in geographically closed regions, and that their effects can be overcome by additional gene copies collectively shaping the evolutionary dynamics of duplicated genes during population history.

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Reproductive Strategies of the Seagrass Zostera japonica Under Different Geographic Conditions in Northern China

Frontiers in Marine Science ◽

10.3389/fmars.2020.574790 ◽

2020 ◽

Vol 7 ◽

Author(s):

Shidong Yue ◽

Xiaomei Zhang ◽

Shaochun Xu ◽

Yu Zhang ◽

Peng Zhao ◽

...

Keyword(s):

Sexual Reproduction ◽

Asexual Reproduction ◽

Reproductive Strategies ◽

Geographic Location ◽

Dry Weight ◽

Northern China ◽

Shoot Density ◽

Zostera Japonica ◽

Sexual And Asexual Reproduction ◽

Density And Biomass

Seagrasses form a unique group of submerged marine angiosperms capable of both sexual and asexual reproduction. The amounts of sexual and asexual reproduction differ within some species relying on geographic location and environmental factors. Here, we studied the reproductive strategies of different geographic Zostera japonica populations, S1 and S2 at Swan Lake lagoon (SLL), and H1 and H2 at Huiquan Bay (HQB), in northern China. The duration of flowering at SLL was longer than at HQB, whereas flowering initiation at HQB occurred earlier than at SLL. In addition, the timing of seed maturation at HQB occurred earlier than at SLL. The allocation to sexual reproduction at SLL was greater than at HQB. The maximum potential seed production was greatest at S1 (22228.52 ± 8832.46 seeds ⋅ m–2), followed by S2 (21630.34 ± 9378.67 seeds ⋅ m–2), H2 (7459.60 ± 1779.33 seeds ⋅ m–2), and H1 (2821.05 ± 1280.57 seeds ⋅ m–2). The seasonal changes in total shoot density and biomass were small at HQB. There was a relatively large number of overwintering shoots at HQB because of the higher average temperature during winter. The allocation to sexual reproduction was lower than at SLL, and no seedlings were observed at HQB during our study. Thus, the population of Z. japonica at HQB was maintained by asexual reproduction. Compared with HQB, the biomass of overwintering shoots at SLL was less than 30 g dry weight ⋅ m–2. The Z. japonica at SLL relied on asexual and sexual reproduction to maintain the population. The results show the necessity of understanding local reproductive strategies before starting restoration and management projects. The study provides fundamental information and guidance for the conservation and restoration of seagrass beds.

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Reproductive strategies in hermaphroditic gastropods: conceptual and empirical approaches

Canadian Journal of Zoology ◽

10.1139/cjz-2012-0272 ◽

2013 ◽

Vol 91 (6) ◽

pp. 367-381 ◽

Cited By ~ 32

Author(s):

Yumi Nakadera ◽

Joris M. Koene

Keyword(s):

Sexual Selection ◽

Reproductive Success ◽

Experimental Research ◽

Reproductive System ◽

Reproductive Strategy ◽

Reproductive Strategies ◽

Sex Allocation ◽

Fitness Consequences ◽

The Individual ◽

Empirical Approaches

An individual optimizes its reproductive success by adopting a particular reproductive strategy. Studying the details of a reproductive strategy leads to an understanding of how sexual selection acts, as the former is the process via which the individual reproduces successfully. Hermaphroditic gastropods display a bewildering diversity of reproductive strategies, which may be due to their mode of gender expression, when compared with well-studied separate-sexed species. Extensive theoretical, observational, and experimental research has been conducted on this topic. However, despite our knowledge about the reproductive system of hermaphroditic gastropods, we still need to fill the gap between pre- and post-copulatory processes and reproductive success. Here, we review and propose conceptual and empirical approaches aimed at understanding reproductive strategies of hermaphroditic gastropods. In sum, our suggestions are (i) to focus on sex-biased traits, (ii) to take biologically reliable measurements at both the pre- and post-copulatory level that relate to reproductive success, and (iii) to examine the fitness consequences of biased sex allocation.

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HORDEIN VARIATION IN WILD (HORDEUM SPONTANEUM) AND CULTIVATED (H. VULGARE) BARLEY

Canadian Journal of Genetics and Cytology ◽

10.1139/g79-043 ◽

1979 ◽

Vol 21 (3) ◽

pp. 391-404 ◽

Cited By ~ 94

Author(s):

Hans Doll ◽

A. H. D. Brown

Keyword(s):

Linkage Disequilibrium ◽

Wild Species ◽

Storage Protein ◽

Natural Populations ◽

Hordeum Spontaneum ◽

Allele Frequencies ◽

Evolutionary Processes ◽

Highly Correlated ◽

The Individual ◽

Allozyme Loci

The storage protein hordein contains two major groups of polypeptides which are highly polymorphic in barley, and in its evolutionary progenitor Hordeum spontaneum Koch. Crosses between the two species showed that the complex electrophoretic phenotypes within the two groups of polypeptides are governed by codominant alleles at two corresponding loci, Hor-1 and Hor-2, which are moderately linked (11% ± 2). In natural populations of the wild species, the two complex hordein loci were much more polymorphic than the allozyme loci. Furthermore, the variation at these two loci was highly correlated so that individuals differ from one another at both loci much more frequently than expected from the allele frequencies at the individual loci. Considerable hordein variation was also present in Composite Cross XXI, and there was evidence of reassortment of patterns by the seventeenth generation. Thus the complex hordein loci, with their extreme diversity and linkage disequilibrium, are ideal markers for monitoring evolutionary processes in both natural, or composite cross populations.

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Extreme Y chromosome polymorphism corresponds to five male reproductive morphs

10.1101/2020.08.19.258434 ◽

2020 ◽

Author(s):

Benjamin A Sandkam ◽

Pedro Almeida ◽

Iulia Darolti ◽

Benjamin Furman ◽

Wouter van der Bijl ◽

...

Keyword(s):

Body Size ◽

Y Chromosome ◽

Mating Behavior ◽

Sex Chromosomes ◽

Reproductive Strategy ◽

Reproductive Strategies ◽

Natural Populations ◽

Chromosome Polymorphism ◽

Y Chromosomes ◽

Adaptive Diversity

AbstractSex chromosomes form once recombination is halted between the X and Y chromosomes. This loss of recombination quickly depletes Y chromosomes of functional content and genetic variation, which is thought to severely limit their potential to generate adaptive diversity. We examined Y diversity in Poecilia parae, where males occur as one of five discrete morphs, all of which shoal together in natural populations where morph frequency has been stable for over 50 years. Each morph utilizes different complex reproductive strategies, and differ dramatically from each other in color, body size, and mating behavior. Remarkably, morph phenotype is passed perfectly from father to son, indicating there are five Y haplotypes segregating in the species, each of which encodes the complex male morph characteristics. Using linked-read sequencing on multiple P. parae females and males of all five morphs from natural populations, we found that the genetic architecture of the male morphs evolved on the Y chromosome long after recombination suppression had occurred with the X. Comparing Y chromosomes between each of the morphs revealed that although the Ys of the three minor morphs that differ predominantly in color are highly similar, there are substantial amounts of unique genetic material and divergence between the Ys of the three major morphs that differ in reproductive strategy, body size and mating behavior. Taken together, our results reveal the extraordinary ability of evolution to overcome the constraints of recombination loss to generate extreme diversity resulting in five discrete Y chromosomes that control complex reproductive strategies.Significance StatementThe loss of recombination on the Y chromosome is thought to limit the adaptive potential of this unique genomic region. Despite this, we describe an extraordinary case of Y chromosome adaptation in Poecilia parae. This species contains five co-occurring male morphs, all of which are Y-linked, and which differ in reproductive strategy, body size, coloration, and mating behavior. The five Y-linked male morphs of P. parae evolved after recombination was halted on the Y, resulting in five unique Y chromosomes within one species. Our results reveal the surprising magnitude to which non-recombining regions can generate adaptive diversity and have important implications for the evolution of sex chromosomes and the genetic control of sex-linked diversity.

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Photo degradation kinetics of insensitive munitions constituents nitroguanidine, nitrotriazolone, and dinitroanisole in natural waters

10.21079/11681/41900 ◽

2021 ◽

Author(s):

Lee Moores ◽

Stacy Jones ◽

Garrett George ◽

David Henderson ◽

Timothy Schutt

Keyword(s):

Laboratory Experiments ◽

Natural Waters ◽

Matrix Effects ◽

Degradation Kinetics ◽

Relative Rate ◽

Ph Dependence ◽

Degradation Pathway ◽

Quantum Yields ◽

The Individual ◽

Kinetics Of

Herein the matrix effects on the kinetics of aqueous photolysis for the individual munitions constituents of IMX-101: nitroguanidine (NQ), dinitroanisole (DNAN), and nitrotriazolone (NTO) are reported along with the environmentally relevant kinetics and quantum yields. Photolysis potentially represents a major degradation pathway for these munitions in the environment and further understanding the complex matrices effects on photolytic kinetics was needed. Aqueous systems are of particular interest due to the high solubility of NQ (3,800 ppm) and NTO (16,642 ppm) compared to the traditional munitions trinitrotoluene (TNT, 100.5 ppm) and 1,3,5-trinitro-1,3,5-triazine (RDX, 59.9 ppm). Environmental half-lives (and quantum yields) were found to be 0.44 days, 0.83 days, and 4.4 days for NQ, DNAN, and NTO, respectively, under natural sunlight. In laboratory experiments using nominally 300 nm bulbs in a merry-go-round style reactor in DI water the relative rate of photolysis for the three munitions constituents followed the same order NQ > DNAN > NTO, where DNAN and NTO reacted 57 and 115 times more slowly, respectively, than NQ. In the various environmentally relevant matrices tested in the laboratory experiments NQ was not significantly affected, DNAN showed a faster degradation with increasing ionic strength, and NTO showed a modest salinity and pH dependence on its rate of photolysis.

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Investigation of Chemical Constituents of Eranthis longistipitata (Ranunculaceae): Coumarins and Furochromones

International Journal of Molecular Sciences ◽

10.3390/ijms23010406 ◽

2021 ◽

Vol 23 (1) ◽

pp. 406

Author(s):

Andrey S. Erst ◽

Alexander A. Chernonosov ◽

Natalia V. Petrova ◽

Maxim S. Kulikovskiy ◽

Svetlana Yu. Maltseva ◽

...

Keyword(s):

High Resolution Mass Spectrometry ◽

Chemical Constituents ◽

Natural Populations ◽

Individual Compound ◽

Physiological Processes ◽

Structural Formulas ◽

Different Populations ◽

Ethanol Extracts ◽

The Individual ◽

First Time

Aqueous-ethanol extracts (70%) from the leaves of Eranthis longistipitata Regel. (Ranunculaceae Juss.)—collected from natural populations of Kyrgyzstan—were studied by liquid chromatography with high-resolution mass spectrometry (LC-HRMS). There was no variation of the metabolic profiles among plants that were collected from different populations. More than 160 compounds were found in the leaves, of which 72 were identified to the class level and 58 to the individual-compound level. The class of flavonoids proved to be the most widely represented (19 compounds), including six aglycones [quercetin, kaempferol, aromadendrin, 6-methoxytaxifolin, phloretin, and (+)-catechin] and mono- and diglycosides (the other 13 compounds). In the analyzed samples of E. longistipitata, 14 fatty acid–related compounds were identified, but coumarins and furochromones that were found in E. longistipitata were the most interesting result; furochromones khelloside, khellin, visnagin, and cimifugin were found in E. longistipitata for the first time. Coumarins 5,7-dihydroxy-4-methylcoumarin, scoparone, fraxetin, and luvangetin and furochromones methoxsalen, 5-O-methylvisammioside, and visamminol-3′-O-glucoside were detected for the first time in the genus Eranthis Salisb. For all the above compounds, the structural formulas are given. Furthermore, detailed information (with structural formulas) is provided on the diversity of chromones and furochromones in other representatives of Eranthis. The presence of chromones in plants of the genus Eranthis confirms its closeness to the genus Actaea L. because chromones are synthesized by normal physiological processes only in these members of the Ranunculaceae family.

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Genetic Variation in Early Growth and Bud Production among Natural Populations of Fraser Fir

HortScience ◽

10.21273/hortsci.43.3.661 ◽

2008 ◽

Vol 43 (3) ◽

pp. 661-666 ◽

Cited By ~ 2

Author(s):

Jennifer L. Emerson ◽

John Frampton ◽

Steven E. McKeand

Keyword(s):

Natural Populations ◽

Christmas Tree ◽

Individual Tree ◽

Great Smoky Mountains ◽

Fraser Fir ◽

Seed Sources ◽

Tree Quality ◽

The Individual ◽

Source Site ◽

Tree Production

A series of open-pollinated progeny tests of Fraser fir [Abies fraseri (Pursh) Poir.] was analyzed to determine natural variation among six geographic seed sources and to estimate genetic parameters for traits important in Christmas tree production. Highly significant differences were found among seed sources and families within sources (P ≤ 0.0001) for height after 4 years in the field. The individual-tree within-population heritability values for the traits measured in Year 4 ranged from 0 to 0.44, with height having the highest heritability, overall tree quality having a heritability of 0.14, and bud and branching traits having varying heritabilities. Heritability values for height at age 4 varied greatly among the six sources, from 0.15 for the Black Mountains to 0.67 for the Great Smoky Mountains. Highly significant seed source × site interactions as well as family within source × site interactions existed for height. Stability variance analysis, after removing the environmental heterogeneity, showed significant instability across the test sites for two of the six seed sources for height after 4 years, and some rank changes occurred. The high heritability values for height indicate that economically important genetic gains can be made in Fraser fir for Christmas tree production because of the importance of height in determining Christmas tree value.

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Sex ratios in natural populations of Drosophila pseudoobscura from Mexico

Genetika ◽

10.2298/gensr1203491s ◽

2012 ◽

Vol 44 (3) ◽

pp. 491-498 ◽

Cited By ~ 1

Author(s):

Victor Salceda ◽

Carolina Arceo-Maldonado

Keyword(s):

Sex Ratio ◽

Sex Chromosome ◽

Natural Populations ◽

Diploid Species ◽

Drosophila Pseudoobscura ◽

Adult Offspring ◽

Equal Proportion ◽

X Chromosomes ◽

The Individual ◽

Number Of Males

Most species show an equal proportion of individuals of both sexes. In diploid species sex ratio is determined by a genic balance between sex chromosomes. In Drosophila sex is determined by the ratio of X- chromosomes versus autosomes and in some species of the genus it is related to the presence of an inversion in the sex chromosome. The present work analyses the sex ratio in 27 natural populations of Drosophila pseudoobscura that inhabit Mexico. Female flies captured in nature were counted and their sex ratio calculated and been called generation P, then cultured individualy, allowed to leave adult offspring which was quantified in order to get its sex ratio and designated generation F1. sex ratio was calculated using the expression: number of males times 100 divided by the number of females proposed by Darwin (1871). The sex ratio of each population was taken using the average of all the individual counts from each sample. The values found varied among different generations and populations, so for generation P their values varieded 37.4 to 190.4 and in generation F1 from 31.3 up to 96.4 males for each 100 females. According to their geographical distribution four North to South transects were arranged and in them means varied from 60.8 to 81.7 males for each 100 females. All this means that in Mexican population are more females than males, exceptionally more males than females.

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