Subsidized harvest of invasive silver carp Hypopthalmichthys molitrix and bighead carp H. nobilis (collectively referred to as Asian carp) from the Illinois River have been initiated in an effort to control their populations. However, market-driven control strategies have been suggested in an effort to reduce or eliminate the need for subsidies. Given that Asian carp are not a favored food fish in the U.S. and exporting to Asian markets is currently not economically feasible, industrial applications such as fish meal production have been explored. Fish meal production to support aquafeed manufacturing is potentially a high-value, high-volume market which is essential to a market-driven approach. However, the nutrient composition of Asian carp as a raw material from the Illinois River needs to be evaluated as well as the nutrient digestibility and production performance of a rendered Asian carp fish meal product to fully assess its suitability for use in aquafeeds. To determine the suitability of Asian carp to support aquafeed manufacturing, we evaluated seasonal and geographical differences in Asian carp harvested from the Illinois River, performed standard digestibility trials with hybrid striped bass and rainbow trout, and assessed production performance through standard feeding trials with hybrid striped bass, rainbow trout, and cobia. Results indicate slight geographical and seasonal variation in body composition, though both species represent protein-dense raw materials suitable for fish meal production. Additionally, Asian carp fish meal is a highly digestible feedstuff that closely resembles the nutrient content of traditional menhaden fish meal sources, although it is slightly less digestible. Production performance of fish fed practical Asian carp fish meal based diets was similar to those that used menhaden fish meal. Overall, Asian carp fish meal appears to be a highly-digestible, nutrient-dense ingredient suitable for inclusion in aquafeeds. Therefore, rendering Asian carp into fish meal appears to be a viable market-driven approach to help control Asian carp populations.

Invasive plant species have widespread effects on the ecosystems they inhabit. Extensive research has been done on the economic and ecological impact of invasive species in relation to native plant species, but little is known about the effect of these species on native fauna. My study examined the impact of an invasive plant species Elaeagnus umbellata (autumn olive) on small mammals populations in southern Illinois. Elaeagnus umbellata is a native shrub of southeast Asia and was introduced to the United States in the 1830s. It is now the fifth most abundant invasive plant species in the state of Illinois. To determine the impact of this invasive shrub on small mammal populations, Sherman traps were set up in six separate trapping webs, three in upland forests with heavy E. umbellata cover and three in upland forests with little to no E. umbellata cover (control). Trapping spanned three seasons from March-August 2013. Through the use of capture and release methods, individuals were measured, weighed, and marked for possible recapture. Beginning in season 3, Cuterebra fontinella (bot fly) abundance in small mammals was also assessed. Differences in relative abundance of small mammal populations were determined using a repeated measures ANOVA with a Tukey test. T-tests were used to determine any significant difference among small mammals between forest types. Very little difference was found among the measured variables between the invaded and control forest sites. Prevalance of C. fontinella was also similar, but the resulting percentage of infection was much higher when compared to other studies in the literature. These results indicate there is little effect of E. umbellata on small mammal populations, although the long-term impacts of this invasive species may need further research.

An effective incentivized hunting program was initiated in the United States in 2002 to reduce the population of nutria (Myocastor coypus), an invasive species of rodent contributing to wetland erosion. In this thesis, I analyze the ethics of intervening through the nutria hunting program by applying four different non-anthropocentric theories of animal and environmental ethics to the case: Peter Singer’s utilitarianism, Tom Regan’s animal rights, Paul Taylor’s respect for nature, and Aldo Leopold’s land ethic. I explain why the theories of Singer and Leopold would support intervention, while Regan’s and Taylor’s would not. Additionally, due to its unique features, the situation with the nutria is a perfect test case for evaluating the merits of these four competing theories. After taking issue with Singer’s, Regan’s, and Taylor’s theories as they pertain to the nutria case, I conclude that Leopold’s land ethic is best able to account for our considered moral belief that killing the invasive nutria in order to protect the wetlands is morally appropriate. Because Leopold’s land ethic is holistic and inegalitarian, it can explain both why the nutria are a problem and why they are less morally valuable than the native wetland species they are destroying. Of the four theories, only Leopold’s includes the entire biotic community in the sphere of moral consideration, and in so doing, recognizes that what is at stake in this case is the wetland itself, and that we have a duty to preserve its integrity, even at the cost of nutria life.

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Made available in DSpace on 2014-06-11T19:32:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-31Bitstream added on 2014-06-13T21:03:44Z : No. of bitstreams: 1 poletto_ab_dr_botib.pdf: 1705638 bytes, checksum: 76b096174aaade2107a2ac15d63db4a2 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho teve por objetivo analisar citogeneticamente espécies da família Cichlidae de diferentes origens. Foram feitas análises de uma espécie asiática, de 22 africanas e 30 neotropicais. O número diplóide na família variou de 2n=40 a 2n=60. Os sítios de genes de RNAr 18S variaram de 2 a 9 cromossomos portadores, com sítios terminais para os africanos e em apenas um grande par cromossômico em posição intersticial ou terminal para a maioria dos neotropicais. A hibridação do gene RNAr 5S marcou sítios múltiplos em regiões intersticiais e centroméricas em duas espécies africanas, enquanto que nos ciclídeos neotropicais marcou de um a dois pares, sempre em posição intersticial. Em Haplocromis obliquidens foram encontrados um a dois grandes cromossomos metacêntricos supernumerários e heterocromáticos em 39,6% da população, tanto em fêmea quanto em macho. Este cromossomo B apresentou sítios múltiplos de hibridação de DNAr 18S e sinais leves na região centromérica do DNA satélite centromérico SATA. Sequências repetitivas inseridas em BACs hibridaram de forma difusa por toda a extensão do elemento supernumerário. Esse cromossomo B pode ter se originado a partir de um isocromossomo, ou por acúmulo de DNA repetitivo num pequeno proto-cromossomo B. Em Metriaclima lombardoi um grande cromossomo B metacêntricoe heterocromático foi detectado em 50% das fêmeas e em nenhum macho. Este elemento não apresentou sinais de hibridação de DNAr 18S, porém DNAs repetitivos inseridos em BACs hibridaram nos braços menores do primeiro par do complemento A, fortemente na região centromérica, e de forma difusa ao longo do cromossomo B. Hipotetizamos que este cromossomo B pode ter se originado a partir de um fragmento do primeiro par do complemento A, tendo acumulado DNAs repetitivos como consequência da ausência de recombinação. Sugerimos também que a origem... / This work had the aim of cytogenetic analyses of Cichlidae species from diverse origin. It was analyzed one asian, 22 african and 30 neotropical species. The diploid number ranged between 2n=40 and 2n=60 chromosomes. The 18S rRNA gene sites varied from two to nine bearer chromosomes, in terminal position for the africans ones, and just in one large chromosome pair, in interstitial or terminal position, for the majority of the neotropical ones. The hybridization with 5S rRNA genes labeled multiple sites in two African species, in centromeric and interstitial position, whereas in the Neotropical cichlids it labeled interstitially in one to two pairs of chromosomes. In Haplochromis obliquidens it was found one or two metacentric supernumerary heterochromatic chromosome(s) in 39,6% of the population including males as well as females. This B chromosome showed multiple hybridization sites of 18S rDNA and the SATA centrometromeric satellite DNA slightly labeled in the cetromeric region, while BAC-clone enriched of repeated sequences hybridized scattered along the B chromosome. This B chromosome could have originated from an isochromosome or by accumulation of repetitive DNA in a small proto-B chromosome. In Metriaclima lombardoi a large heterochromatic metacentric B chromosome was detected in 50% of females and none males. This element did not show signals of hybridization of 18S rDNA but BAC-clone enriched of repeated DNAs hybridized in the small arms of first pair of complement, strongly in the centromeric region, and scattered along the B chromosome. We hypothesized that this B chromosome could have originated from a fragment of the A complement, and had acumulated repetitive DNAs as consequence of absence of recombination. We also suggest that the origin of this B from the first chromosome pair could be driving the bearer individuals to present female characteristics independently... (Complete abstract click electronic access below)

Orientador: Marcos Gomes Nogueira / Banca: Lilian Casatti / Banca: Mário Luís Orsi / Banca: Ricardo Motta Pinto Coelho / Banca: Ângelo Antônio Agostinho / Resumo: O presente estudo foi conduzido em quatro lagoas marginais da porção superior do reservatório de Rosana, bem como no canal principal do rio Paranapanema. O objetivo do primeiro capítulo foi analisar a composição e os atributos ecológicos das assembléias fitoplanctônicas, recurso trófico primário das cadeias alimentares aquáticas. O segundo capítulo trata da comunidade zooplanctônica (Cladocera e Copepoda) e sua distribuição nos ambientes analisados. O terceiro trabalho procura avaliar se a introdução de uma espécie exótica de peixe (Cichla kelberi) pode causar alterações na estrutura da ictiofauna local, com uma possível redução da sua diversidade. Por fim, o quarto capítulo refere-se à alimentação da ictiofauna de pequeno porte, através da análise da dieta e do hábito alimentar das espécies, considerando principalmente a importância da comunidade planctônica para essa fauna. O número total de táxons de fitoplâncton identificados foi de 283. Zygnemaphyta foi o grupo com maior número de espécies, seguido por Chlorophyta e Bacillariophyta. Maior riqueza, abundância e biomassa de fitoplâncton foram observadas nas lagoas, especialmente durante o período chuvoso. O número total de táxons de zooplâncton identificados foi de 72. As lagoas laterais e o período chuvoso apresentaram maior abundância de organismos. Calanoida foi o grupo dominante nas assembléias zooplanctônicas. Os resultados mostraram que no sistema de lagoas laterais as comunidades são controladas por mecanismos ascendentes ("bottom-up"). Um total de 4693 peixes, pertencentes a 43 espécies foram amostrados. A Ordem Characiformes foi a mais abundante, seguida por Perciformes e Siluriformes. Não houve diferenças estatísticas na riqueza, na abundância, na biomassa, na média do comprimento, na composição das assembléias e na diversidade de peixes, comparando-se o período... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The study was carried out in four lateral lagoons of the tail region of Rosana reservoir, as well as in the river/reservoir main channel. The aim of the first chapter of the thesis was to analyze the composition and ecological attributes of the phytoplankton assemblages, primordial trophic resource of the aquatic food chains. The second chapter is focused on the zooplankton community (Cladocera and Copepoda) and their distribution in the study environments. The third chapter tries to assess whether the introduction of a non native fish species (Cichla kelberi) may promote alterations in the local ichthyofauna, with a possible reduction in its diversity. Finally, the last chapter discusses the ichthyofauna feeding, through the analysis of diet and feeding behavior of fish, considering mainly the importance of plankton organisms as a resource. The total number of phytoplankton taxa identified was of 283. Zygnemaphyta was the most specious group, followed by Chlorophyta and Bacillariophyta. Higher richness, abundance and biomass were observed in the lagoons, especially during the rainy period. The total number of zooplankton taxa was 72. Higher zooplankton abundance was observed in the lateral lagoons and in the rainy period. Calanoids were the dominant group in the zooplankton assemblages. The results indicated that in the lateral lagoons system, the communities are controlled by bottom-up mechanisms. A total of 4,693 fish, belonging to 43 species was sampled between 2004 and 2009. The order Characiformes was the most abundant, followed by Perciformes and Siluriformes. There were no differences in composition, richness, abundance, biomass, mean length and diversity, when compared the periods previous and after the introduction of Cichla. The results showed that the feeding of the river fish assemblages was different from the lagoons... (Complete abstract click electronic access below) / Doutor

The thesis explores how the range sizes of carnivorans are shaped by geographic and evolutionary constraints. Employing modern spatial analyses and phylogenetic comparative methods, we illustrate that phylogenetically conserved climate tolerances delimit species? geographic constraints, which in turn shape the species? range size. Range size heritability patterns emerge as a consequence of this interplay between geographic and evolutionary constraints.

Abstract Genetic diversity in three taiga specialists – the Siberian tit (Parus cinctus), the Siberian jay (Perisoreus infaustus) and the Siberian flying squirrel (Pteromys volans) – was assessed by comparing DNA sequence variation across the mitochondrial control region and allele frequencies of microsatellites from samples collected from Fennoscandia and Siberia. Population sizes of these species have declined in association with fragmentation and loss of suitable forest habitat due to modern forestry practices in Fennoscandia. The red squirrel (Sciurus vulgaris) served as a reference for the flying squirrel. Genetic differentiation among species studied ranged from a panmictic population in the Siberian tit to that of the strong differentiation of populations (θST = 53%) in the flying squirrel in Finland. MtDNA and microsatellite data, together with assignment studies, showed the Siberian jay population to be significantly genetically structured and supported the existence of a metapopulation like structuring in Fennoscandia. Division of genetic variation among flying squirrel populations along the ancient shoreline of the Littorina Lymnea Sea stage of the Baltic Sea (7000 BP) and two geographically associated branches in the minimum spanning network supported a two-way colonisation history for the species. The Finnish inland appears to have been colonised from the east in association with the arrival of Norway spruce. At the same time, Coastal Finland was colonised from the south-east through the Karelian Isthmus. Gene flow of the species appeared female biased and restricted. Species exhibiting more restrictive dispersal characteristics and habitat requirements possessed stronger population genetic structure than those with opposite characteristics. Growth or contractions in population size leave characteristic signatures in mtDNA that can be studied by comparing different sequence diversity estimates among populations. I applied this method to the species studied. Significant differences in nucleotide diversities indicated restrictions in gene flow among populations in all species studied. Half of the Siberian jay populations gave a signal of population size bottleneck. All the species studied showed differences in their population genetic structures across their entire distribution ranges consistent with the multirefugia model, most likely to be attributable to differences in their ecological characteristics and Pleistocene histories.

Abstract Most models of sexual selection focus on coevolution of male sexual trait and female preference for the trait. However, whether the female preference modifies the male trait depends on the overall receptivity of females, on the importance of the male trait for the females, on female sampling behaviour, and on female control over copulation decision. These aspects are often neglected by theoreticians. Female receptivity, song requirement and preferences were studied in two Drosophila virilis group species, D. montana and D. virilis. The main object of the study was female acceptance/rejection behaviour. Female wing spreading posture was a signal for males to attempt copulation, when the female was ready to mate. I used this signal as an indicator of female acceptance. D. virilis females were generally very receptive, but there were differences between females both in receptivity and in responsiveness of the females to simulated courtship songs. D. virilis female did not require song and had a low acceptance threshold with a heterospecific male. These two traits are explained by a high female receptivity. D. montana females, on the contrary, had a high acceptance threshold. These females accepted the courting male only after hearing his song. They also repelled males, which attempted copulation without female acceptance signal. In this species the strength of species discrimination did not correlate with the overall receptivity of the females. Between species hybrid females (from a cross vir x mo and from backcross to mo) resembled D. montana females in their song requirement, but not in their receptivity. This suggests that these two traits are inherited independently. D. montana and D. littoralis females have previously been found to prefer males with short and dense sound pulses in wild. These song characters were repeatable among overwintered males in a fashion different from other song characters. This shows that song characters involved in sexual selection are more sensitive to environmental factors than other song traits.

Ceratocystis is a genus of Ascomycete fungi residing in the family Ceratocystidaceae (Order: Microascales; Class: Sordariomycetes). Species of Ceratocystis are best-known as woundinfecting fungi, which are mostly carried by insects. Little is known regarding the basis of the relationship between insects and Ceratocystis spp., but in some cases it might extend to levels of mutualism. The taxonomic history of the genus is complex and has, during the course of more than 100 years, been intertwined with several other genera. However, in recent years, the resolution arising from DNA sequence comparisons has resulted in the recognition of at least four major groups within Ceratocystis. major groups within Ceratocystis. Ceratocystis species in the broad sense (including Ambrosiella) represent ecologically diverse assemblages, including four very clearly defined groups. One of these groups, which I refer to as the C. coerulescens sensu lato (s.l.) group, which mainly cause blue-stain in timber, is the only group that is known to have a very close association with conifer-infesting bark beetles. Perhaps the best-known group is the C. fimbriata s.l. assemblage of species, which includes a large number of serious pathogens of angiosperms, mostly trees. This group also includes nonpathogenic wound-infecting species. There are no specific insect vectors of these species but they produce fruity aromas, which attract a wide range of insects such as flies, ants, mites and nitidulid beetles that aid in their dissemination to fresh wounds. The majority of the species in the C. fimbriata s.l. group are primary pathogens causing cankers that can girdle and eventually kill the affected areas. The third group of fungi in the broadly defined Ceratocystis s.l. is the C. moniliformis s.l. group. This group includes only saprophytes that, similar to species in C. fimbriata s.l., produce fruity odours and they are thus vectored by opportunistic insects including flies and nitidulid beetles. Ambrosiella spp. are broadly included in the assemblage accommodating Ceratocystis spp. These fungi have no known sexual state and they live in obligate symbioses with ambrosia beetles (Scolytinae). Ceratocystis and its relatives have had a complex taxonomic history ever since the genus was first described by Halstead in 1890. Much of the confusion regarding their taxonomy has arisen from a dependence on morphology for classification and the fact that these and other fungi have undergone convergent evolution related to their association with insects. Until the late 1990s, genera and species in this group were described based only on morphology, although the importance of various morphological features was strongly debated. However, between 1950- 1999, a turning point arose in the way that these fungi were recognised. This change emerged first from the inclusion of various chemical approaches and then later the application of molecular techniques to identify them. The most dramatic changes have come with the widespread application of DNA sequence comparisons, which were first applied to the group in the early 1990’s. This made it possible to define higher-order relationships and brought the first clear evidence that species in Ceratocystis and Ophiostoma were phylogenetically unrelated. A complete taxonomic history of this group is provided in the timeline presented in Table 1. This thesis deals primarily with two groups in the broadly defined Ceratocystis. These are species in the C. moniliformis s.l. and the C. fimbriata s.l. complexes, but with a considerably greater focus on the C. fimbriata s.l. complex. Morphologically, species in the two complexes are easy to distinguish from each other even though they share some common characteristics. Species in both complexes have hat-shaped ascospores and both have the anamorphic characteristics typical of species in the genus Thielaviopsis. The ascomatal bases are mostly globose to sub-globose with elongated necks. There are two main features that species in the C. moniliformis s.l. complex have that are not observed in the C. fimbriata s.l. complex. One is a very distinct “collar-like” structure at the base of the ascomatal necks of species in the C. moniliformis s.l. complex. These “collar-like” structures result in the necks being fragile and they dislodge from the ascomatal bases very easily. The other distinct characteristic is that these fungi have conical spines on their ascomatal bases, giving the structures a textured appearance. This is in contrast to the ascomatal bases in the C. fimbriata complex that are smooth. Species in the C. moniliformis s.l. complex are non-pathogenic and cause only some sap-stain in the host tissues. The C. fimbriata s.l. complex includes a large number of primary pathogens, mainly of trees but also including root crops. A phylogenetic tree including all species in the C. fimbriata s.l and C. moniliformis s.l. complexes is presented in Figure 1-3. In generating this tree, three gene regions i.e. the Internal Transcribed Spacer Region including the 5.8S rRNA operon (ITS), part of the the Beta-Tubulin 1 (BT) gene and part of the Transcription Elongation Factor 1 alpha (TEF) gene have been combined to represent species in the two complexes. Both Bootstrap as well as Bayesian analyses were run to obtain confidence intervals. More detailed methods are presented in the legends to the trees. Chapter one of this thesis presents a review of the groups in Ceratocystis. With the aid of DNA sequence comparisons, three phylogenetically distinct groups are identified. These groups are characterised by three well-known species each now defined as a species complex i.e. the Ceratocystis coerulescens complex, the C. moniliformis s.l. complex and the C. fimbriata s.l. complex. Species of Ambrosiella are also recognised as representing a discrete and related group. These three species complexes are not only differentiated based on DNA sequence comparison but have distinct morphological features that distinguish them from each other. They are also defined by having very distinct ecological roles in nature. Chapter 2 specifically reviews the key literature dealing with the taxonomy of species in the C. fimbriata complex. This group is defined by Ceratocystis fimbriata s.s., which was first described as a pathogen causing black rot on sweet potato. Subsequent to the emergence of DNA sequencing techniques to define species, many new species in the C. fimbriata s.l. complex have been defined and described. Chapters three and four of this thesis deal with a species of Ceratocystis collected from dying Mango trees in Oman. A very serious disease known as Mango Sudden Decline disease was first observed in Oman and has recently been subjected to intensive investigation. This led to a recognition that a species related to C. fimbriata might be responsible for the disease of Mangifera indica. As part of the process of identifying the causal agent of Mango Sudden Decline, two Ceratocystis spp. were described. One is the previously described and nonpathogenic C. omanensis residing in the C. moniliformis s.l. complex and the other is C. manginecans, a virulent pathogen residing in the C. fimbriata s.l. complex (Chapter 4). Chapters five through eleven of this thesis include the descriptions of new species in the C. fimbriata complex that have emerged over a seven year period. These descriptions have all relied strongly on DNA sequence based phylogenetic inference as well as morphology. It is important to recognise, however, that the morphological features are very similar in most species and that differences rely on the size ranges of key features in this group. The genus Ceratocystis represents a complex of many species and is set to be sub-divided into at least three discrete genera, not including Ambrosiella, which is also closely related and already well-defined. Studies in this thesis began at a time when it became possible to define species of Ceratocystis based strongly on a phylogenetic concept. Thus, while morphological and ecological features were taken into account, there has been a heavy reliance on DNA sequence comparisons. It is likely that in coming years, new gene regions will be recognised that will allow a refinement of genus and species boundaries. Furthermore, having access to whole-genome sequencing will add deeply to our understanding of taxonomic relationships between these important and fascinating fungi. It is my hope that the foundation provided by the studies incorporated in this thesis will be useful as this new wave of study emerges. / Thesis (PhD)--University of Pretoria, 2013. / gm2013 / Genetics / unrestricted