Mating System Analysis Research Articles

Contrasting levels of extra-pair paternity in mainland and island populations of the house sparrow (Passer domesticus): is there an ‘island effect’?

Despite the many studies that have investigated the genetic mating system of socially monogamous birds, very little is known about the underlying causes of extra-pair paternity and few studies have attempted to test those hypotheses which have been suggested. This study describes the analysis of the genetic mating system of two populations of the house sparrow (Passer domesticus), and uses the results from four other populations to test existing hypotheses using an intra-specific comparative approach. The parentage analysis was conducted using a combination of published and newly presented microsatellite loci isolated from the house sparrow. One population in Kentucky, U.S.A. was found to contain what may be considered to be a typical level of extra-pair paternity for this species (10.5%, 19/185 offspring). The second, a population on the island of Lundy, UK, exhibited a very low level (1.3%, 4/305 offspring), significantly lower than that in all the other populations studied so far. The finding of such diverse rates of extra-pair paternity, along with the existing estimates from other populations, has allowed us to test the effects of breeding density and genetic variation on the level of extra-pair paternity. We found no effect of either factor on the frequency of extra-pair paternity in the house sparrow, leaving the cause of this variation open to fresh ideas.

Contrasting levels of extra-pair paternity in mainland and island populations of the house sparrow (Passer domesticus): is there an «island effect»?

Despite the many studies that have investigated the genetic mating system of socially monogamous birds, very little is known about the underlying causes of extra-pair paternity and few studies have attempted to test those hypotheses which have been suggested. This study describes the analysis of the genetic mating system of two populations of the house sparrow (Passer domesticus), and uses the results from four other populations to test existing hypotheses using an intra-specific comparative approach. The parentage analysis was conducted using a combination of published and newly presented microsatellite loci isolated from the house sparrow. One population in Kentucky, U.S.A. was found to contain what may be considered to be a typical level of extra-pair paternity for this species (10.5%, 19/185 offspring). The second, a population on the island of Lundy, UK, exhibited a very low level (1.3%, 4/305 offspring), significantly lower than that in all the other populations studied so far. The finding of such diverse rates of extra-pair paternity, along with the existing estimates from other populations, has allowed us to test the effects of breeding density and genetic variation on the level of extra-pair paternity. We found no effect of either factor on the frequency of extra-pair paternity in the house sparrow, leaving the cause of this variation open to fresh ideas.

EVIDENCE FOR AN EXTREME BOTTLENECK IN A RARE MEXICAN PINYON: GENETIC DIVERSITY, DISEQUILIBRIUM, AND THE MATING SYSTEM IN PINUS MAXIMARTINEZII.

Maxipiñon (Pinus maximartinezii Rzedowski), which is confined to a single population of approximately 2000 to 2500 mature trees, covers about 400 ha in southern Zacatecas, Mexico. Genetic diversity measured by expected heterozygosity was 0.122, which is moderate for pines. However, percentage polymorphic loci was low, 30.3%. The fixation index (F) of 0.081 indicated only slight heterozygote deficiency. Mating system analysis indicated a significant but low level of selling; the multilocus outcrossing rate, tm , was 0.816. The mean of single locus estimates, ts , was smaller (0.761), perhaps suggesting mating among relatives, although the difference between tm and ts was not statistically significant. The most striking features of maxipiñon's genetic structure were that no polymorphic locus had more than two alleles and most alleles at polymorphic loci were at intermediate frequencies. This is in contrast to other pines, which often have three to five or more alleles at some loci and in which the distribution of allele frequencies is U-shaped, most alleles being present at frequencies less than 10% or greater than 90%. A population with only two alleles per locus and at intermediate frequencies could occur if the population had been reduced to an extreme bottleneck and then expanded rapidly before random drift modified allele frequencies. A novel origin from a hybridization event would also explain the results. Significant gametic disequilibrium was detected at several pairs of loci in both maternal and paternal gametes. The presence of disequilibrium is in agreement with an origin from an extreme bottleneck, perhaps even a single seed. Furthermore, it demands that the event be relatively recent. The number of generations, as calculated from the observed mean disequilibrium, suggested that maxipiñon derived from an extreme bottleneck four to five generations ago, which is less than 1000 years in this species.

DNA preparation and efficient microsatellite analysis from insect hemolymph.

A simple and time-saving method for DNA preparation for efficient microsatellite analysis is described. The method is based on thermal treatment of only 1-5 microL of insect hemolymph in a Chelex 100-suspension. Since hemolymph withdrawal does not harm the insects, analysis of mating systems, population structure and phylogenetic reconstruction can be conducted with minimal experimental influence.

Towards second-generation STS (sequence-tagged sites) linkage maps in conifers: a genetic map of Norway spruce (Picea abies K.).

Genetic linkage maps have been produced for a wide range of organisms during the last decade, thanks to the increasing availability of molecular markers. The use of microsatellites (or Simple Sequence Repeats, SSRs) as genetic markers has led to the construction of "second-generation" genetic maps for humans, mouse and other organisms of major importance. We constructed a second-generation single-tree genetic linkage map of Norway spruce (Picea abies K.) using a panel of 72 haploid megagametophytes with a total of 447 segregating bands [366 Amplified Fragment Length Polymorphisms (AFLPs), 20 Selective Amplification of Microsatellite Polymorphic Loci (SAMPLs) and 61 SSRs, each single band being treated initially as a dominant marker]. Four hundred and thirteen markers were mapped in 29 linkage groups (including triplets and doublets) covering a genetic length of 2198.3 cM, which represents 77.4% of the estimated genome length of Picea abies (approximately 2839 cM). The map is still far from coalescing into the expected 12 chromosomal linkage groups of Norway spruce (2n = 2x = 24). A possible explanation for this comes from the observed non-random distribution of markers in the framework map. Thirty-eight SSR marker loci could be mapped onto 19 linkage groups. This set of highly informative Sequence Tagged Sites (STSs) can be used in many aspects of genetic analysis of forest trees, such as marker-assisted selection, QTL mapping, positional cloning, gene flow analysis, mating system analysis and genetic diversity studies.

Evidence of Outcrossing in Trillium erectum and Trillium grandiflorum (Liliaceae)

Journal of Heredity 1997:88:325-329; 0022-1503/97/S5.00 Enzyme electrophoresis was used to Investigate aiiozyme diversity and outcrossing rates In a population of Trillium erectum and T. grandiflorum from central New York. Enzyme polymorphisms were observed for 11 of 14 and 7 of 13 loci examined in T. erectum and T. grandiflorum, respectively. Percent polymorphic loci (P), mean number of alleles per locus (A), and mean expected heterozygosities («.) were greater In T. erectum {P = 78.6%; A = 2.48; H. = 0.220) than in T. grandiflorum (P = 43.6%; A = 2.18; H. = 0.130). Neither species showed a net excess nor deficiency of heterozygotes as measured by fixation Indices. These levels of aiiozyme diversity are more typical of species with outcrossing breeding systems than species with selflng breeding systems. A mating system analysis revealed that outcrossing is high In T. grandiflorum (^ = 0.761 ± 0.076; x ± SD). In contrast, the selflng rate In T. erectum was nearly 57% (^ = 0.423 ± 0.093) more typical of a species with a mixed-mating system. Nevertheless, these data strongly challenge the view that selflng breeding systems are typical of all North American species of Trillium.

Isolation and characterization of microsatellite loci from the planarian Dugesia polychroa (Schmidt) (Platyhelminthes:Tricladida).

Molecular EcologyVolume 6, Issue 4 p. 389-391 Isolation and characterization of microsatellite loci from the planarian Dugesia polychroa (Schmidt) (Platyhelminthes: Tricladida) S. Ramachandran, S. Ramachandran Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this authorL. W. Beukeboom, L. W. Beukeboom Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this authorL. Gerace, L. Gerace Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this authorN. Pavlovic, N. Pavlovic Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this authorS. Carranza, S. Carranza Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this authorN. K. Michiels, N. K. Michiels Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this author S. Ramachandran, S. Ramachandran Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this authorL. W. Beukeboom, L. W. Beukeboom Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this authorL. Gerace, L. Gerace Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this authorN. Pavlovic, N. Pavlovic Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this authorS. Carranza, S. Carranza Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this authorN. K. Michiels, N. K. Michiels Arbeitsgruppe Michiels, Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, GermanySearch for more papers by this author First published: 31 October 2003 https://doi.org/10.1046/j.1365-294X.1997.00190.xCitations: 4 Dr L. Beukeboom Tel.: +49-8157-932254 or 232; Fax: +49-8157 932400 or -209. E-mail: [email protected] AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article.Citing Literature Volume6, Issue4April 1997Pages 389-391 RelatedInformation

Natural selection of UDP genotypes in an experimental population of Lolium perenne (Poaceae)

The mating system determines the range of genotypes on which selection will act. Ultimately, the population will contain only those genotypes that can survive in the current environment. This study was conducted to determine the extent to which selection affects genotype at four enzyme loci in Lolium perenne. Starch gel electrophoresis was used to determine genotype at the phosphoglucomutase, 6‐phosphogluconate dehydrogenase, phosphoglucose isomerase, and UDP‐glucose pyrophosphorylase loci. Genotypes of progeny arrays were used to infer maternal genotype in a field‐grown population of plants. A mating system analysis was performed on maternal and progeny plants of the field population and also on a population of plants, from the same seed stock, grown in a greenhouse environment. Allelic frequencies differed among populations at the Udp locus. Results indicate that high mortality in the field strongly favored one allele. Assumptions of the mating system model are examined and used to interpret the observed differentiation among populations.

COSTS OF REPRODUCTION INFLUENCE THE EVOLUTION OF SEXUAL SIZE DIMORPHISM IN SNAKES.

Most explanations for sex differences in adult body size have focused on differences between the two sexes in the degree to which larger body size enhances reproductive success. For example, the general tendency for females to grow larger than males has been attributed to production of larger litters by larger females (Darwin 1871; Trivers 1972; but see Shine 1988), and the correlation between large male size and mating systems with male-male competition has led many authors to conclude that larger male size enhances male reproductive success in such systems (Darwin 1871; Clutton-Brock et al. 1977; Shine 1978; Berry and Shine 1980). Because each of these hypotheses deals only with the relationship between body size and reproductive success within one sex, no prediction can be made about the relative sizes of the two sexes (Greenwood and Adams 1987; Shine 1987). The degree of size dimorphism is presumably determined by the relative intensities of selection for large size in the two sexes, as well as the degree of genetic correlation between the sexes for alleles associated with body size (Arnold 1985). It is entirely likely that large size enhances reproductive success in both sexes, but more strongly in one than in the other. In order to predict the actual direction or degree of sexual size dimorphism within a population, we need data on the effects of body size on reproductive success in both sexes. Such data are rarely available (Clutton-Brock 1988), so the balance between selective forces acting on conspecific males and females has rarely been evaluated. A comparative analysis of sexual size dimorphism and mating systems in snakes reveals that females grow larger than males in most species, but not in species that show male-male combat behavior (Shine 1978). The same pattern has been noted in many other animals, including other reptiles, and generally has been attributed to sexual selection for large male body size in taxa with male-male combat (Shine 1979; Berry and Shine 1980; Fitch 1981). Nonetheless, there are many exceptions to this generalization, and the most puzzling of these are species in which male-male combat occurs but in which females attain larger sizes than males. Species that fail to conform to the usual pattern may tell us a great deal about the factors responsible for those general patterns. In this paper, we use detailed demographic and ecological data on one of these atypical species (the adder Vipera berus) to test among potential explanations for female-larger dimorphism in a species with male-male combat. Our analyses suggest that sex differences in costs of reproduction may strongly influence optimal body sizes in each sex, and hence may affect the direction of sexual size dimorphism. We focus here on the potential costs and benefits of larger body size in terms of reproductive success, especially, fecundity selection in females and sexual selection in males.

Global analysis of a two-allele mating system

The global analysis of a two-allele mating system is provided. One allele is dominant to the other. Mating is random, but mating between unlike phenotypes has a lower fertility than that between like phenotypes. The generations are discrete and non-overlapping. The population is considered to be infinite, and the model is deterministic. There are three equilibria of the difference equations. Two of the equilibria are the (two) homozygous states, and these are asymptotically stable. The third equilibrium is polymorphic but is unstable. It is proven that almost all populations converge to one of the two homozygous states. The remaining populations converge to the unstable equilibrium, and lie on a curve that separates the basins of attraction for the other two equilibria. This curve is shown to satisfy some simple properties.

Analysis of mating systems in the schistosome-vector hermaphrodite snail Bulinus globosus by DNA fingerprinting.

Bulinus globosus, one of the intermediate hosts for Schistosoma, is a hermaphrodite freshwater snail. Multilocus DNA fingerprinting was applied in order to investigate the mating system of this facultatively self-fertilizing species. By analysing DNA fingerprints of eight broods, we have shown that selfed and outcrossed individuals could be unambiguously distinguished by comparison with their parent fingerprints. First, selfed offspring patterns shared a higher number of bands with their mother than did outcrossed ones. Secondly, at least three paternal bands could be detected per outcrossed offspring pattern.

Mating system analysis in Pinus leucodermis Ant.: detection of self-fertilization in natural populations

Mating system analysis in Pinus leucodermis Ant.: detection of self-fertilization in natural populations

Mating system analysis in a central and Northern European population of picea abies

Mating system and genetic variability were studied in a southern and a northern population of Picea abies, in Czechoslovakia and Finland. Both populations had considerable genetic variability, with expected heterozygosities of 0.17 and 0.23, respectively, at nine loci. The two distant populations were more differentiated (Gst = 0.12) than has been found in studies on Scandinavian Picea abies. Both populations had a considerable degree of partial selfing, with estimates of outcrossing of 0.83 and 0.74 in the populations from Czechoslovakia and Finland, respectively.

Genetics of Brazil nut (Bertholletia excelsa Humb. & Bonpl.: Lecythidaceae)

Here we report the results of a mating system analysis of an Amazonian population of Bertholletia excelsa, a tropical rain forest canopy tree species. Using progeny data from 29 seed parents, two highly polymorphic isozymes were analyzed to derive single locus and multilocus estimates of outcrossing, based on a mixed mating model. The two single locus estimates were very similar, and both were somewhat smaller than the multilocus estimate, indicating the possibility that the populations are genetically structured. The multilocus outcrossing estimate (tm=0.85±0.03) reveals that outcrossing is prevalent, but that a significantly low level of inbreeding may be occurring. The high outcrossing rate indicates that even though dispersion of individuals is very low within populations of this tropical rain forest tree, pollen dispersal mechanisms appear to be adequate to enable crosses with a relatively large number of potential mates.

Male mate-locating behavior inEuphydryas chalcedona (Lepidoptera: Nymphalidae) related to pupation site preferences

Males of the checkerspot butterfly (Euphydryas chalcedona)patrol and perch near but not on the larval foodplant in search of females. Experiments with tethered butterflies show that searching males chase virgin females for longer times than they do mated females or males. The larvae leave the larval food-plant to pupate. The correspondence between the distance from the larval foodplant to pupation sites and where males search for females suggests that male mate-locating behavior has evolved to maximize the rate of encounters with newly emerged, virgin females. These conclusions are compared to a recent analysis of butterfly mating systems by Odendaal et al. (Am. Nat.125: 673–678, 1985).

Hilltopping Behavior of Polistes commanchus navajoe (Hymenoptera: Vespidae)

AbstractMales of the paper wasp Polistes commanchus aggregate in large numbers on hilltops in central and southeastern Arizona where individual males defend perch sites on shrubs, trees or rocks. Residents chase intruders away quickly and exhibit strong site fidelity at their perches. Takeovers are rare as are prolonged battles for possession of a site. Males have only weak preferences for peaktop perch sites as opposed to those lower on hillsides, and a similarly weak preference for perches in shrubs as opposed to those on rocks. Receptive females appear occasionally at the male aggregation sites to mate with perch holders. The relatively weak territoriality exhibited by P. commanchus may stem in part from the high density of males at peaktops and the correspondingly high rate of interactions. The evolution of hilltopping in a species whose reproductive females are clumped spatially at nest sites poses a puzzle for the ecological analysis of mating systems.

Comparative analysis of mating systems and marriage distance patterns in five tribal groups of Andhra Pradesh, India.

Abstract Various studies on marriage patterns in India have indicated that the incidence of consanguineous marriages varies according to linguistic groups. This study was carried out in an area of culture contact of several different linguistic groups. A study of five endogamous tribal groups showed that the degree of consanguinity and type of consanguineous marriages were closely related to the linguistic area to which each population belonged. The Raj Gonds, Kolams, and Pradhans had a high inbreeding coefficient similar to that of rural populations of Andhra Pradesh; the Andhs showed a lower coefficient similar to that of Maharashtra, their area of origin; and the Mathuras, a nomadic North Indian group, showed a very low inbreeding coefficient, which is characteristic of North India.

Loss of selectively neutral alleles in small populations and regular mating systems

An exact description of the complete process of pure random drift at a multiallelic locus is extremely difficult. However, if we are concerned only with the number of alleles remaining rather than their frequencies, the problem can be reduced to the level of two alleles. General formulas for the mean, variance, and probability distribution of n, the number of alleles remaining after a given number of generations, are obtained and applied to various models of reproduction. For the Wright model of random sampling, n takes on a nearly symmetrical distribution during the early generations, with its first two moments easily approximated for moderately large (> 10 haploids) populations. Diploid systems of random mating, double first-cousin mating, and circular mating are also analyzed. Circular mating loses fewer alleles than the other two systems even though double first-cousin mating preserves more heterozygosity during the early generations. Maintenance of heterozygosity and maintenance of alleles might be considered alternative approaches to the analysis of mating systems.

The Absence of Genetic Load in a Morphologically Variable Sexual Species, Ceratopteris thalictroides (Parkeriaceae)

Genetic and mating system analysis of Ceratopteris thalictroides indicates that recessive deleterious and lethal genes (genetic load) are rare or non-existent in most sporophytes studied, although nearly all plants exhibit high probabilities of an outbreeding reproductive system in gametophyte populations. Genetic load expres- sion is shown to be directly correlated with three complementary parameters of gametophyte morphology (gametangia sequence of hermaphroditic prothalli, ratio of male to hermaphrodites, and number dehisced antheridia in the two gametophyte types). Population studies indicate that most populations are genetically depauperate for lethal genes and that there is a direct relationship between population size and percent of sporophytes with deleterious genes. The low level of genetic load in most populations is hypothesized to be due to their mode of establishment, age, and frequency of vegetative reproduction. Ceratopteris forms a complex array of species which are unique among homosporous ferns in several features. They are aquatic, annual, some- what weedy, reproduce profusely vegetatively from sporophytic buds (Lloyd, 1973, 1974a), and produce a gametophyte generation which ex- hibits rapid development and sexual maturation, and chemical antheri- dogens. In addition, recent work by Klekowski (1973a), Klekowski and Hickok (1974), and Hickok (1977a, 1978) indicates that homoeologous pairing during meiosis occurs and can produce an array of spore ge- notypes even from genetically homozygous individuals. As presently circumscribed, the genus is composed of four broadly defined species, three diploids, C. cornuta (Palisot de Beauvois) Le Prieur, C. pteridoides (W. J. Hooker) Hieronymus, C. richardii Brongniart, and one tetraploid/hexaploid, C. thalictroides (Linnaeus) Brongniart (Lloyd, 1974a). Hickok (1977b) has found that the diploid species are actively