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Glanville Fritillary Butterfly (glanville + fritillary_butterfly)
Selected AbstractsGenetics of personalities: no simple answers for complex traitsMOLECULAR ECOLOGY, Issue 4 2010BARBARA TSCHIRREN Identifying the genes that underlie phenotypic variation in natural populations, and assessing the consequences of polymorphisms at these loci for individual fitness are major objectives in evolutionary biology. Yet, with the exception of a few success stories, little progress has been made, and our understanding of the link between genotype and phenotype is still in its infancy. For example, although body length in humans is largely genetically determined, with heritability estimates greater than 0.8, massive genome-wide association studies (GWAS) have only been able to account for a very small proportion of this variation (Gudbjartsson et al. 2008). If it is so difficult to explain the genetics behind relatively ,simple' traits, can we envision that it will at all be possible to find genes underlying complex behavioural traits in wild non-model organisms? Some notable examples suggest that this can indeed be a worthwhile endeavour. Recently, the circadian rhythm gene Clock has been associated with timing of breeding in a wild blue tit population (Johnsen et al. 2007; Liedvogel et al. 2009) and the Pgi gene to variation in dispersal and flight endurance in Glanville fritillary butterflies (Niitepold et al. 2009). A promising candidate gene for influencing complex animal personality traits, also known as behavioural syndromes (Sih et al. 2004), is the dopamine receptor D4 (DRD4) gene. Within the last decade, polymorphisms in this gene have been associated with variation in novelty seeking and exploration behaviour in a range of species, from humans to great tits (Schinka et al. 2002; Fidler et al. 2007). In this issue, Korsten et al. (2010) attempt to replicate this previously observed association in wild-living birds, and test for the generality of the association between DRD4 and personality across a number of European great tit populations. [source] Life-history, genotypic, and environmental correlates of clutch size in the Glanville fritillary butterflyECOLOGICAL ENTOMOLOGY, Issue 2 2007MARJO SAASTAMOINEN Abstract 1.,Glanville fritillary butterfly (Melitaea cinxia) females lay up to 10 clutches of 50,300 eggs in their lifetime. Clutch size is an important life-history trait as larval group size affects survival throughout larval development. 2.,Two experiments were carried out in a large population cage in the field to investigate the life-history and environmental correlates of clutch size. 3.,Clutch size decreased with the cumulative number of eggs laid previously, increased with both female body weight and the number of days between consecutive clutches. 4.,Genotypic differences among females in the glycolytic enzyme phosphoglucose isomerase had a significant influence on clutch size, partly because females of particular genotypes were able to initiate oviposition earlier in the day and thereby take advantage of the most favourable environmental conditions for oviposition. 5.,Factors influencing clutch size were partly different in two summers, indicating the modulating effect of prevailing environmental conditions on reproductive performance. [source] Fitness differences associated with Pgi SNP genotypes in the Glanville fritillary butterfly (Melitaea cinxia)JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2009L. ORSINI Abstract Allozyme variation at the phosphoglucose isomerase (PGI) locus in the Glanville fritillary butterfly (Melitaea cinxia) is associated with variation in flight metabolic rate, dispersal rate, fecundity and local population growth rate. To map allozyme to DNA variation and to survey putative functional variation in genomic DNA, we cloned the coding sequence of Pgi and identified nonsynonymous variable sites that determine the most common allozyme alleles. We show that these single-nucleotide polymorphisms (SNPs) exhibit significant excess of heterozygotes in field-collected population samples as well as in laboratory crosses. This is in contrast to previous results for the same species in which other allozymes and SNPs were in Hardy,Weinberg equilibrium or exhibited an excess of homozygotes. Our results suggest that viability selection favours Pgi heterozygotes. Although this is consistent with direct overdominance at Pgi, we cannot exclude the possibility that heterozygote advantage is caused by the presence of one or more deleterious alleles at linked loci. [source] The effects of habitat destruction in finite landscapes: a chain-binomial metapopulation modelOIKOS, Issue 2 2001Mark F. Hill We present a stochastic model for metapopulations in landscapes with a finite but arbitrary number of patches. The model, similar in form to the chain-binomial epidemic models, is an absorbing Markov chain that describes changes in the number of occupied patches as a sequence of binomial probabilities. It predicts the quasi-equilibrium distribution of occupied patches, the expected extinction time ( ), and the probability of persistence ( ) to time x as a function of the number N of patches in the landscape and the number S of those patches that are suitable for the population. For a given value of N, the model shows that: (1) and are highly sensitive to changes in S and (2) there is a threshold value of S at which declines abruptly from extremely large to very small values. We also describe a statistical method for estimating model parameters from time series data in order to evaluate metapopulation viability in real landscapes. An example is presented using published data on the Glanville fritillary butterfly, Meltiaea cinxia, and its specialist parasitoid Cotesia melitaearum. We calculate the expected extinction time of M. cinxia as a function of the frequency of parasite outbreaks, and are able to predict the minimum number of years between outbreaks required to ensure long-term persistence of M. cinxia. The chain-binomial model provides a simple but powerful method for assessing the effects of human and natural disturbances on extinction times and persistence probabilities in finite landscapes. [source] |