Clinal variation in life-history traits of the invasive plant species Echium plantagineum L.

University of Technology, Sydney. Faculty of Science.Range expansion during the invasion of a novel environment requires that invading species adapt to geographical variation in climate and maintain positive population growth in the face of environmental heterogeneity. Thus, invasive species are expected to undergo adaptive evolutionary changes as they encounter novel selection pressures. The aim of this thesis was to identify adaptive changes in plant growth and reproductive traits throughout the lifecycle of a model invasive species to determine which traits are vital to the success of invasive species encountering novel environments. The model species used in this study was the widespread European invader, Echium plantagineum, which has invaded over 33 million ha across Australia, causing ~$30 million (AUD) damage per annum. I investigated geographic variation in life-history traits of 34 populations of E. plantagineum across a 1,000 km arid-mesic gradient throughout south-eastern NSW, Australia. Seeds were collected for each population along the arid-mesic gradient, germinated in the laboratory and grown in the glasshouse in a common environment. I found that E. plantagineum has rapidly adapted to environmental selection pressures throughout its range, resulting in two major clines linked to plant flowering time and seed size of progeny. Compared with populations from mesic habitats along the arid-mesic gradient, plant populations from arid environments had significantly higher relative growth rate and leaf production which was associated with much earlier flowering time and reduced time between stem production and flower production. Plants from arid regions also produced significantly larger seeds compared with plants from mesic habitats. Interestingly, seeds from all E. plantagineum populations along the arid-mesic gradient germinated rapidly (within 48 hours of water exposure) allowing them to quickly and opportunistically take advantage of available resources. Considered together, these adaptations allow E. plantagineum to grow rapidly, reproduce and produce progeny before conditions become unsuitable. The findings in this thesis provide compelling evidence for the rapid development, within 150 years, of clines in reproductive strategies linked to flowering and seed size evolution. My results support the notion that the successful invasive spread of species can be increased through genetic divergence of populations along arid-mesic climatic gradients. The climate of south-eastern Australia is predicted to change to become hotter and drier inducing many species to adapt or perish. The range and distribution of E. plantagineum is unlikely to be altered by these climatic changes as pre-adapted genotypes currently exist in the range margins and have persisted in arid regions for over 100 years. Consequently, further work is required to investigate the evolutionary capacity of other native and invasive species to determine how ecosystem dynamics and composition may change in the future

Rapid Development of Adaptive, Climate-Driven Clinal Variation in Seed Mass in the Invasive Annual Forb Echium plantagineum L.

We examined adaptive clinal variation in seed mass among populations of an invasive annual species, Echium plantagineum, in response to climatic selection. We collected seeds from 34 field populations from a 1,000 km long temperature and rainfall gradient across the species' introduced range in south-eastern Australia. Seeds were germinated, grown to reproductive age under common glasshouse conditions, and progeny seeds were harvested and weighed. Analyses showed that seed mass was significantly related to climatic factors, with populations sourced from hotter, more arid sites producing heavier seeds than populations from cooler and wetter sites. Seed mass was not related to edaphic factors. We also found that seed mass was significantly related to both longitude and latitude with each degree of longitude west and latitude north increasing seed mass by around 2.5% and 4% on average. There was little evidence that within-population or between-population variation in seed mass varied in a systematic manner across the study region. Our findings provide compelling evidence for development of a strong cline in seed mass across the geographic range of a widespread and highly successful invasive annual forb. Since large seed mass is known to provide reproductive assurance for plants in arid environments, our results support the hypothesis that the fitness and range potential of invasive species can increase as a result of genetic divergence of populations along broad climatic gradients. In E. plantagineum population-level differentiation has occurred in 150 years or less, indicating that the adaptation process can be rapid. © 2012 Konarzewski et al

DETEKTOR IGŁOWY PROMIENIOWANIA X I GAMMA

The article presents the developed structure of the novel needle proportional gas detector (NPC – Needle Proportional Counter) used for the detection of X-rays and gamma rays. The advantage of the detector is its simple mechanical construction and the possibility of detection of incident radiation in a direction parallel to the needle. The measured energy spectrum of the isotope Fe-55 by means of the developed detector is presented. Artykuł przedstawia opracowaną konstrukcję nowego typu gazowego detektora igłowego, służącego do detekcji promieniowania X i gamma. Zaletą detektora jest jego prosta konstrukcja mechaniczna i możliwość detekcji promieniowania w kierunku równoległym do igły. Zmierzono widmo energetyczne izotopu Fe-55 opracowanym detektorem

Timelessness of mies van der rohe’s houses architecture in the twenties of the XX century in ban shigeru’s case study project – sagaponac house #4 from XXI century – extended version

This paper presents a method of forming detached houses architecture in modern times. Taking advantage of the inspiration on unrealized concept of building from the year 1924 has been indicated. The realization of Sagaponac House #4 from 2006 has been compared with the project of Brick Country House from Twenties of previous century

MHC influences infection with parasites and winter survival in the root vole Microtus oeconomus

Selective pressure from parasites is thought to maintain the polymorphism of major histocompatibility complex (MHC) genes. Although a number of studies have shown a relationship between the MHC and parasitic infections, the fitness consequences of such associations are less well documented. In the present paper, we characterised the variation in exon 2 of MHC class II DRB gene in the root vole and examined the effects of that gene on parasite prevalence and winter survival. We identified 18 unique exon 2 sequences, which translated into 10 unique amino acid sequences. Phylogenetic analysis revealed the presence of three distinct clusters, and allele distributions among these individuals suggested that the clusters correspond to three different loci. Although the rate of synonymous substitutions (dS) exceeded the rate of nonsynonymous substitutions (dN) across sequences, implying purifying selection, dN was significantly elevated at antigen-binding sites, suggesting that these sites could be under positive selection. Screening for parasites revealed a moderate prevalence of infection with gastrointestinal parasites (24 % infected), but a high infection rate for blood parasites (56 % infected). Infection with the blood parasite Babesia ssp. decreased survival almost twofold (25.7 vs. 13.9 %). Animals possessing the amino acid sequence AA*08 survived better than others (44.9 vs. 22 %), and they were infected with Babesia ssp. less often (13.9 vs 25.7 %). In contrast, individuals carrying allele AA*05 were infected more often (31.7 vs. 15.3 %). Heterozygosity at one of the putative loci was associated with a lower probability of infection with Babesia ssp., but at the other locus, the association was reversed. The unexpected latter result could be at least partly explained by the increased frequency of the susceptible allele AA*05 among heterozygotes. Overall, we demonstrate that infection with Babesia ssp. is a strong predictor of winter survival and that MHC genes are important predictors of infection status as well as survival in the root vole

Brain size, gut size and cognitive abilities : the energy trade-offs tested in artificial selection experiment

The enlarged brains of homeotherms bring behavioural advantages, but also incur high energy expenditures. The ‘expensive brain’ (EB) hypothesis posits that the energetic costs of the enlarged brain and the resulting increased cognitive abilities (CA) were met by either increased energy turnover or reduced allocation to other expensive organs, such as the gut. We tested the EB hypothesis by analysing correlated responses to selection in an experimental evolution model system, which comprises line types of laboratory mice selected for high or low basal metabolic rate (BMR), maximum (VO2max) metabolic rates and random-bred (unselected) lines. The traits are implicated in the evolution of homeothermy, having been pre-requisites for the encephalization and exceptional CA of mammals, including humans. High-BMR mice had bigger guts, but not brains, than mice of other line types. Yet, they were superior in the cognitive tasks carried out in both reward and avoidance learning contexts and had higher neuronal plasticity (indexed as the long-term potentiation) than their counterparts. Our data indicate that the evolutionary increase of CA in mammals was initially associated with increased BMR and brain plasticity. It was also fuelled by an enlarged gut, which was not traded off for brain size