CiteULike: Tag guppy

Evaluation of the Rate of Evolution in Natural Populations of Guppies (Poecilia reticulata)

David Reznick — 2006-03-20T00:41:18-00:00

Science, Vol. 275, No. 5308. (28 March 1997), pp. 1934-1937.

Linkage mapping of AFLP and microsatellite DNA markers with the body color- and sex-determining loci in the guppy (Poecilia reticulata).

T Watanabe — 2006-06-11T05:49:33-00:00

Zoolog Sci, Vol. 22, No. 8. (August 2005), pp. 883-889.

The guppy is an ornamental fish species that exhibits various phenotypic characteristics, such as body color and fin-shape. Although linkage relationships of a limited number of phenotypic traits have already been investigated, the association between phenotypic and molecular markers is still unknown. We constructed a total of 35 linkage groups for the guppy using 186 polymorphic loci of AFLP and microsatellite DNA. The locus related to the yellow body color was linked with ten markers and the sex-determination locus was linked with five markers.

Biologically meaningful expression profiling across species using heterologous hybridization to a cDNA microarray.

SC Renn — 2006-06-11T05:43:28-00:00

BMC Genomics, Vol. 5, No. 1. (6 July 2004)

BACKGROUND: Unravelling the path from genotype to phenotype, as it is influenced by an organism's environment, is one of the central goals in biology. Gene expression profiling by means of microarrays has become very prominent in this endeavour, although resources exist only for relatively few model systems. As genomics has matured into a comparative research program, expression profiling now also provides a powerful tool for non-traditional model systems to elucidate the molecular basis of complex traits. RESULTS: Here we present a microarray constructed with approximately 4500 features, derived from a brain-specific cDNA library for the African cichlid fish Astatotilapia burtoni (Perciformes). Heterologous hybridization, targeting RNA to an array constructed for a different species, is used for eight different fish species. We quantified the concordance in gene expression profiles across these species (number of genes and fold-changes). Although most robust when target RNA is derived from closely related species (<10 MA divergence time), our results showed consistent profiles for other closely related taxa (approximately 65 MA divergence time) and, to a lesser extent, even very distantly related species (>200 MA divergence time). CONCLUSION: This strategy overcomes some of the restrictions imposed on model systems that are of importance for evolutionary and ecological studies, but for which only limited sequence information is available. Our work validates the use of expression profiling for functional genomics within a comparative framework and provides a foundation for the molecular and cellular analysis of complex traits in a wide range of organisms.

Social networks in the guppy (Poecilia reticulata).

DP Croft — 2006-06-11T05:37:38-00:00

Proc Biol Sci, Vol. 271 Suppl 6 (7 December 2004)

Social network theory is used to elicit details of the social structure of a population of free-ranging guppies, Poecilia reticulata. They were found to have a complex and highly structured social network, which exhibited characteristics consistent with the 'small world' phenomenon. Stable partner associations between individuals were observed, a finding that fulfils the basic prerequisite for the evolution of reciprocal altruism. The findings are discussed in relation to the ecology and evolution of the wild population, highlighting the potential application of network theory to social associations in animals.

Carotenoid availability affects the development of a colour-based mate preference and the sensory bias to which it is genetically linked.

GF Grether — 2006-06-11T05:34:36-00:00

Proc Biol Sci, Vol. 272, No. 1577. (22 October 2005), pp. 2181-2188.

Regardless of their origins, mate preferences should, in theory, be shaped by their benefits in a mating context. Here we show that the female preference for carotenoid colouration in guppies (Poecilia reticulata) exhibits a phenotypically plastic response to carotenoid availability, confirming a key prediction of sexual selection theory. Earlier work indicated that this mate preference is genetically linked to, and may be derived from, a sensory bias that occurs in both sexes: attraction to orange objects. The original function of this sensory bias is unknown, but it may help guppies find orange-coloured fruits in the rainforest streams of Trinidad. We show that the sensory bias also exhibits a phenotypically plastic response to carotenoid availability, but only in females. The sex-specificity of this reaction norm argues against the hypothesis that it evolved in a foraging context. We infer instead that the sensory bias has been modified as a correlated effect of selection on the mate preference. These results provide a new type of support for the hypothesis that mate preferences for sexual characters evolve in response to the benefits of mate choice--the alternatives being that such preferences evolve entirely in a non-mating context or in response to the costs of mating.

Variation in Anti-Predator Behavior Among Five Strains of Inbred Guppies, Poecilia reticulata.

Bronwyn Bleakley — 2006-04-10T19:49:00-00:00

Behav Genet (24 February 2006)

Quantitative genetic studies frequently utilize inbred strains of animals as tools for partitioning the direct and indirect effects of genes from environmental effects in generating an observed phenotype, however, this approach is rarely applied to behavioral studies. Guppies, Poecilia reticulata, perform a set of anti-predator behaviors that may provide an ideal system to study how complex behavioral traits are generated. To assess the utility of ornamental guppies in quantitative genetics studies of behavior, we assayed five morphologically distinct strains of ornamental guppies for response to predator cues and for variation in response among strains. Despite individual variation, all five strains responded to predator cues and differences among strains were found for all assayed behaviors, including measures of boldness and predator avoidance.

The effects of genotype, age, and social environment on male ornamentation, mating behavior, and attractiveness.

LK Miller — 2006-04-05T23:01:36-00:00

Evolution Int J Org Evolution, Vol. 59, No. 11. (November 2005), pp. 2414-2425.

The traits thought to advertise genetic quality are often highly susceptible to environmental variation and prone to change with age. These factors may either undermine or reinforce the potential for advertisement traits to signal quality depending on the magnitude of age-dependent expression, environmental variation, and genotype-age and genotype-environment interaction. Measurements of the magnitude of these effects are thus a necessary step toward assessing the implications of age dependence and environmental variability for the evolution of signals of quality. We conducted a longitudinal study of male guppies (Poecilia reticulata) from 22 full-sibling families. Each fish was assigned at maturity to one of three treatments in order to manipulate his allocation of resources to reproduction: a control in which the male was kept alone, a courtship-only treatment in which he could see and court a female across a clear partition, and a mating treatment in which he interacted freely with a female. We measured each male's size, ornamental color patterns, courtship, attractiveness to females, and mating success at three ages. Size was influenced by treatment and age-treatment interactions, indicating that courtship and mating may impose costs on growth. Tail size and color patterns were influenced by age but not by treatment, suggesting fixed age-dependent trajectories in these advertisement traits. By contrast, display rate and attempted sneak copulation rate differed among treatments but not among ages, suggesting greater plasticity of these behavioral traits. As a result of the different patterns of variation in ornamentation and behavior, male attractiveness and mating success responded to male age, treatment, and the interaction between age and treatment. Neither age nor treatment obscured the presence of genetic variation, and the genetic relationship between male ornamentation and attractiveness remained the same among treatments. Our findings suggest that neither age-dependent variation nor environmentally induced variation in reproductive effort is likely to undermine the reliability of male signaling.

Xiphophorus genetic linkage map: beginnings of comparative gene mapping in fishes.

DC Morizot — 2007-09-14T10:10:21-00:00

Mar Biotechnol (NY), Vol. 3, No. Supplement 1. (June 2001)

The explosive expansion of gene maps of mouse and man has provided strong support for hypotheses first advanced from comparing fish and mammalian genomes that the vertebrate genome was derived from multiple ancestral tetraploidizations with subsequent preferential translocations among paralogous chromosomes. At least two genome duplication events have become widely accepted in lineages leading to vertebrates, and a third has been proposed either before, or after, divergence of fishes and tetrapods. Cytogenetic and comparative gene mapping studies suggest that teleost gene maps have diverged more slowly from gene arrangements in the vertebrate ancestor than have those of mammals. The recent assembly of extensive maps of >100 genes in three fish species, medaka (Beloniformes), Xiphophorus swordtails and platyfishes (Cyprinodontiformes), and zebrafish (Cypriniformes) and the development of less extensive maps in several other fish orders provides the first salient opportunity to assess homology of most or all chromosomes among fishes.

In vitro culture of embryos of the guppy, Poecilia reticulata.

U Martyn — 2006-04-10T19:52:08-00:00

Dev Dyn, Vol. 235, No. 3. (March 2006), pp. 617-622.

The rich variation in adult color patterns of male guppies (Poecilia reticulata) has attracted the attention of geneticists and ecologists for almost a century. Studies on their embryogenesis, however, have been limited by the fact that guppies are live bearers. We have observed normal development after explantation of guppy embryos from the ovary of pregnant females at various times after last parturition, and found that development of each batch of eggs is slightly asynchronous, most likely due to asynchronous fertilization. We have cultured explanted embryos in vitro and continuously observed their development. Although embryos explanted a few days after fertilization survived up to 4 weeks in culture, they did not complete their development. In contrast, embryos explanted at late stages of gestation could hatch and develop to fertile adults. Our embryo culture techniques overcome some of the limitations of using livebearers as study objects, and they allow continuous observation of and accessibility to live embryos at all stages.

Frequency-dependent survival in natural guppy populations

Robert Olendorf — 2006-06-02T07:13:01-00:00

Nature, Vol. 441, No. 7093., pp. 633-636.

Familiarity leads to female mate preference for novel males in the guppy, Poecilia reticulata.

KA Hughes — 2008-06-20T03:52:40-00:00

Animal behaviour, Vol. 58, No. 4. (October 1999), pp. 907-916.

Guppies are a model vertebrate for studies of sexual selection and life history evolution. None the less, there have been few investigations of the factors responsible for maintaining extreme within-population genetic variation in male coloration. In a laboratory study, we tested the hypothesis that frequency-dependent mate choice contributes to the maintenance of this variation. We attempted to avoid biases inherent in earlier studies of the 'rare male effect' by familiarizing females to males bearing a particular colour pattern and later presenting them with alternate male types, in equal numbers. Females were significantly more likely to mate with males having novel colour patterns than with males having a colour pattern with which they were familiar. This result is consistent with the hypothesis that mate choice is frequency dependent. Other factors such as male and female size were unrelated to mate preference. Implications of the results for theories of sexual selection and the maintenance of variation are discussed. Copyright 1999 The Association for the Study of Animal Behaviour.

Variation in the appearance of guppy color patterns to guppies and their predators under different visual conditions

John Endler — 2008-04-15T21:58:42-00:00

Vision Research, Vol. 31, No. 3. (1991), pp. 587-608.

Color patterns of natural populations of guppies (Poecilia reticulata) are a compromise between sexual selection and predation avoidance. Field data on ambient light spectra, water transmission spectra, courtship and attack distances, and cone pigments of guppies and their predators were used to calculate measures of conspicuousness of guppies under various combinations of visual conditions and vision. The results suggest that color patterns are relatively more conspicuous to guppies at the times and places of courtship and relatively less conspicuous at the times and places of maximum predator risk. Some implications to the evolution of vision, visual communication and behavior are discussed.

Evolution of juvenile growth rates in female guppies (Poecilia reticulata): predator regime or resource level?

JD Arendt — 2008-04-07T06:25:08-00:00

Proceedings. Biological sciences / The Royal Society, Vol. 272, No. 1560. (7 February 2005), pp. 333-337.

Recent theoretical and empirical work argues that growth rate can evolve and be optimized, rather than always being maximized. Chronically low resource availability is predicted to favour the evolution of slow growth, whereas attaining a size-refuge from mortality risk is predicted to favour the evolution of rapid growth. Guppies (Poecilia reticulata) evolve differences in behaviour, morphology and life-history traits in response to predation, thus demonstrating that predators are potent agents of selection. Predators in low-predation environments prey preferentially on small guppies, but those in high-predation environments appear to be non-selective. Because guppies can outgrow their main predator in low- but not high-predation localities, we predict that predation will select for higher growth rates in the low-predation environments.However, low-predation localities also tend to have lower productivity than high-predation localities, yield-ing the prediction that guppies from these sites should have slower growth rates. Here we compare the growth rates of the second laboratory-born generation of guppies from paired high- and low-predation localities from four different drainages. In two out of four comparisons, guppies from high-predation sites grew significantly faster than their low-predation counterparts. We also compare laboratory born descendants from a field introduction experiment and show that guppies introduced to a low-predation environment evolved slower growth rates after 13 years, although this was evident only at the high food level. The weight of the evidence suggests that resource availability plays a more important role than predation in shaping the evolution of growth rates.

The relative influence of natural selection and geography on gene flow in guppies

Erika Crispo — 2005-12-17T12:34:52-00:00

Molecular Ecology, Vol. 15, No. 1. (January 2006), pp. 49-62.

Balancing selection, random genetic drift, and genetic variation at the major histocompatibility complex in two wild populations of guppies (Poecilia reticulata).

C Van Oosterhout — 2008-04-07T06:19:45-00:00

Evolution; international journal of organic evolution, Vol. 60, No. 12. (December 2006), pp. 2562-2574.

Our understanding of the evolution of genes of the major histocompatibility complex (MHC) is rapidly increasing, but there are still enigmatic questions remaining, particularly regarding the maintenance of high levels of MHC polymorphisms in small, isolated populations. Here, we analyze the genetic variation at eight microsatellite loci and sequence variation at exon 2 of the MHC class IIB (DAB) genes in two wild populations of the Trinidadian guppy, Poecilia reticulata. We compare the genetic variation of a small (Ne, 100) and relatively isolated upland population to that of its much larger (Ne approximately 2400) downstream counterpart. As predicted, microsatellite diversity in the upland population is significantly lower and highly differentiated from the population further downstream. Surprisingly, however, these guppy populations are not differentiated by MHC genetic variation and show very similar levels of allelic richness. Computer simulations indicate that the observed level of genetic variation can be maintained with overdominant selection acting at three DAB loci. The selection coefficients differ dramatically between the upland (s > or = 0.2) and lowland (s < or = 0.01) populations. Parasitological analysis on wild-caught fish shows that parasite load is significantly higher on upland than on lowland fish, which suggests that large differences in selection intensity may indeed exist between populations. Based on the infection intensity, a substantial proportion of the upland fish would have suffered direct or indirect fitness consequences as a result of their high parasite loads. Selection by parasites plays a particularly important role in the evolution of guppies in the upland habitat, which has resulted in high levels of MHC diversity being maintained in this population despite considerable genetic drift.

Gametic isolation in guppies (Poecilia reticulata).

AM Ludlow — 2008-04-07T06:13:00-00:00

Proceedings. Biological sciences / The Royal Society, Vol. 273, No. 1600. (7 October 2006), pp. 2477-2482.

Post-mating reproductive isolating mechanisms may be among the earliest reproductive barriers to emerge among incipient species. Trinidadian guppy, Poecilia reticulata, populations in the Caroni and Oropouche drainages in Northern Trinidad exhibit marked genetic divergence and provide an ideal system in which to search for these barriers. We inseminated virgin females with equal amounts of sperm from two males, a 'native' male from the female's own population and a 'foreign' male from the other drainage. Artificial insemination ensured that mating order and mate choice did not affect the outcome. Paternities were assigned to the resulting broods using microsatellite markers. As predicted, sperm from native males had precedence over foreign sperm. Moreover, this effect was symmetrical for both drainages. In contrast, we detected no native sperm precedence in controls, in which females received sperm from the same and another population within the same drainage. Our results show that gametic isolation can arise between geographically proximate, though genetically divergent, populations of a single species and highlight the potential role of this process in speciation.

Multiple mating and reproductive skew in Trinidadian guppies.

SA Becher — 2008-04-07T05:11:39-00:00

Proceedings. Biological sciences / The Royal Society, Vol. 271, No. 1543. (22 May 2004), pp. 1009-1014.

Male offspring production in promiscuously mating species is typically more skewed than female offspring production. It is therefore advantageous for males to seek as many mating partners as possible. However, given the documented benefits of polyandry we expect females, as well as males, to mate multiply. We tested these ideas using Trinidadian guppies, Poecilia reticulata. Fishes were collected from the wild, housed in groups of 10 males and 10 females and allowed to reproduce freely over a period of three months. We used hypervariable microsatellite loci to identify the parents of 840 offspring and to quantify the variance in mating success. As anticipated, and in line with the Bateman gradient, there was greater skew in the number of progeny produced by males. By contrast, we found no sex difference in mating partner number over the duration of the experiment. A median of two males fathered each brood and there was marked turnover in the identities of the sires of successive broods. Female partner turnover was, however, less than expected under random mating. We suggest that partner switching over time, as well as polyandry within broods, could contribute to the maintenance of genetic diversity in guppy populations.

Multiple paternity and kin recognition mechanisms in a guppy population

Timothy Hain — 2007-09-14T15:19:10-00:00

Molecular Ecology, Vol. 16, No. 18. (September 2007), pp. 3938-3946.

Invasion success and genetic diversity of introduced populations of guppies Poecilia reticulata in Australia

Anna Lindholm — 2005-09-28T13:54:33-00:00

Molecular Ecology, Vol. 14, No. 12. (October 2005), pp. 3671-3682.

Intrinsic reproductive isolation between Trinidadian populations of the guppy, Poecilia reticulata

ST Russell — 2006-06-19T22:29:13-00:00

Journal of Evolutionary Biology, Vol. 19, No. 4. (July 2006), pp. 1294-1303.

Genetic and environmental effects on secondary sex traits in guppies (Poecilia reticulata)

KA Hughes — 2005-01-07T20:44:19-00:00

Journal of Evolutionary Biology, Vol. 18, No. 1., 35.

ESTs and EST-linked polymorphisms for genetic mapping and phylogenetic reconstruction in the guppy, Poecilia reticulata

Christine Dreyer — 2007-08-09T07:42:13-00:00

BMC Genomics, Vol. 8 (08 August 2007), 269.

Effect of temperature on sex ratio in guppy Poecilia reticulata (Peters 1860)

Ismihan Karayucel — 2006-01-18T14:20:34-00:00

Aquaculture Research, Vol. 37, No. 2. (February 2006), pp. 139-150.

Colourful male guppies produce faster and more viable sperm

L Locatello — 2006-08-14T18:16:13-00:00

Journal of Evolutionary Biology, Vol. 19, No. 5. (September 2006), pp. 1595-1602.