Ecology, population genetics and conservation of the African violet

The ongoing rapid fragmentation of tropical forests is a major threat to global biodiversity. This is because many of the tropical forests are so-called biodiversity 'hotspots', areas that host exceptional species richness and concentrations of endemic species. Forest fragmentation has negative ecological and genetic consequences for plant survival. Proposed reasons for plant species' loss in forest fragments are, e.g., abiotic edge effects, altered species interactions, increased genetic drift, and inbreeding depression. To be able to conserve plants in forest fragments, the ecological and genetic processes that threaten the species have to be understood. That is possible only after obtaining adequate information on their biology, including taxonomy, life history, reproduction, and spatial and genetic structure of the populations. In this research, I focused on the African violet (genus Saintpaulia), a little-studied conservation flagship from the Eastern Arc Mountains and Coastal Forests hotspot of Tanzania and Kenya. The main objective of the research was to increase understanding of the life history, ecology and population genetics of Saintpaulia that is needed for the design of appropriate conservation measures. A further aim was to provide population-level insights into the difficult taxonomy of Saintpaulia. Ecological field work was conducted in a relatively little fragmented protected forest in the Amani Nature Reserve in the East Usambara Mountains, in northeastern Tanzania, complemented by population genetic laboratory work and ecological experiments in Helsinki, Finland. All components of the research were conducted with Saintpaulia ionantha ssp. grotei, which forms a taxonomically controversial population complex in the study area. My results suggest that Saintpaulia has good reproductive performance in forests with low disturbance levels in the East Usambara Mountains. Another important finding was that seed production depends on sufficient pollinator service. The availability of pollinators should thus be considered in the in situ management of threatened populations. Dynamic population stage structures were observed suggesting that the studied populations are demographically viable. High mortality of seedlings and juveniles was observed during the dry season but this was compensated by ample recruitment of new seedlings after the rainy season. Reduced tree canopy closure and substrate quality are likely to exacerbate seedling and juvenile mortality, and, therefore, forest fragmentation and disturbance are serious threats to the regeneration of Saintpaulia. Restoration of sufficient shade to enhance seedling establishment is an important conservation measure in populations located in disturbed habitats. Long-term demographic monitoring, which enables the forecasting of a population s future, is also recommended in disturbed habitats. High genetic diversities were observed in the populations, which suggest that they possess the variation that is needed for evolutionary responses in a changing environment. Thus, genetic management of the studied populations does not seem necessary as long as the habitats remain favourable for Saintpaulia. The observed high levels of inbreeding in some of the populations, and the reduced fitness of the inbred progeny compared to the outbred progeny, as revealed by the hand-pollination experiment, indicate that inbreeding and inbreeding depression are potential mechanisms contributing to the extinction of Saintpaulia populations. The relatively weak genetic divergence of the three different morphotypes of Saintpaulia ionantha ssp. grotei lend support to the hypothesis that the populations in the Usambara/lowlands region represent a segregating metapopulation (or metapopulations), where subpopulations are adapting to their particular environments. The partial genetic and phenological integrity, and the distinct trailing habit of the morphotype 'grotei' would, however, justify its placement in a taxonomic rank of its own, perhaps in a subspecific rank.

Landscape ecology and genetics of the wolf in Italy

This PhD Thesis includes five main parts on diverse topics. The first two parts deal with the trophic ecology of wolves in Italy consequently to a recent increase of wild ungulates abundance. Data on wolf diet across time highlighted how wild ungulates are important food resource for wolves in Italy. Increasing wolf population, increasing numbers of wild ungulates and decreasing livestock consume are mitigating wolf-man conflicts in Italy in the near future. In the third part, non-invasive genetic sampling techniques were used to obtain genotypes and genders of about 400 wolves. Thus, wolf packs were genetically reconstructed using diverse population genetic and parentage software. Combining the results on pack structure and genetic relatedness with sampling locations, home ranges of wolf packs and dispersal patterns were identified. These results, particularly important for the conservation management of wolves in Italy, illustrated detailed information that can be retrieved from genetic identification of individuals. In the fourth part, wolf locations were combined with environmental information obtained as GIS-layers. Modern species distribution models (niche models) were applied to infer potential wolf distribution and predation risk. From the resulting distribution maps, information pastures with the highest risk of depredation were derived. This is particularly relevant as it allows identifying those areas under danger of carnivore attack on livestock. Finally, in the fifth part, habitat suitability models were combined with landscape genetic analysis. On one side landscape genetic analyses on the Italian wolves provided new information on the dynamics and connectivity of the population and, on the other side, a profound analysis of the effects that habitat suitability methods had on the parameterization of landscape genetic analyses was carried out to contributed significantly to landscape genetic theory.

Aspects of the biology of Mya arenaria and Ensis spp. (Mollusca; Bivalvia) in the Irish Sea and adjacent areas

This study was undertaken to investigate the general biology, including the reproductive cycle and health status, of two clam taxa in Irish waters, with particular reference to the Irish Sea area. Monthly samples of the soft shell clam, Mya arenaria, were collected from Bannow Bay, Co. Wexford, Ireland, for sixteen months, and of the razor clam, Ensis spp. from the Skerries region (Irish Sea) between June 2010 and September 2011. In 2010, M. arenaria in Bannow Bay matured over the summer months, with both sexes either ripe or spawning by August. The gonads of both sexes of E. siliqua developed over autumn and winter 2010, with the first spawning individuals being recorded in January 2011. Two unusually cold winters, followed by a warmer than average spring, appear to have affected M. arenaria and E. siliqua gametogenesis at these sites. It was noted that wet weight of E. siliqua dropped significantly in the summer of both 2010 and 2011, after spawning, which may impact on the economic viability of fishing during this period. Additional samples of M. arenaria were collected at Flaxfort (Ireland), and Ensis spp. at Oxwich (Wales), and the pathology of all clams was examined using both histological and molecular methods. No pathogenic conditions were observed in M. arenaria while Prokaryote inclusions, trematode parasites, Nematopsis spp. and inflammatory pathologies were observed at low incidences in razor clams from Ireland but not from Wales; the first time these conditions have been reported in Ensis spp. in northern European waters. Mya arenaria from sites in Europe and eastern and western North America were investigated for genetic variation using both mitochondrial (cytochrome oxidase I (COI) and 16S ribosomal RNA genes) and nuclear markers (10 microsatellite loci). Both mitochondrial CO1 and all nuclear markers showed reduced levels of variation in certain European samples, with significant differences in haplotype and allelic composition between most samples, particularly those from the two different continents, but with the same common haplotypes or alleles throughout the range. The appearance of certain unique rare haplotypes and microsatellite alleles in the European samples suggest a complicated origin involving North American colonization but also possible southern European Pleistocene refugia. Specimens of Ensis spp. were obtained from five coastal areas around Ireland and Wales and species-specific PCR primers were used to amplify the internal transcribed spacer region 1 (ITS1) and the mitochondrial DNA CO1 gene and all but 15 razor clams were identified as Ensis siliqua. Future investigations should focus on continued monitoring of reproductive biology and pathology of the two clam taxa (in particular, to assess the influence of environmental change), and on genetics of southern European M. arenaria and sequencing the CO1 gene in Ensis individuals to clarify species identity

Biology of sensory systems

Since publication of the first edition, huge developments have taken place in sensory biology research and new insights have been provided in particular by molecular biology. These show the similarities in the molecular architecture and in the physiology of sensory cells across species and across sensory modality and often indicate a common ancestry dating back over half a billion years. Biology of Sensory Systems has thus been completely revised and takes a molecular, evolutionary and comparative approach, providing an overview of sensory systems in vertebrates, invertebrates and prokaryotes, with a strong focus on human senses. Written by a renowned author with extensive teaching experience, the book covers, in six parts, the general features of sensory systems, the mechanosenses, the chemosenses, the senses which detect electromagnetic radiation, other sensory systems including pain, thermosensitivity and some of the minority senses and, finally, provides an outline and discussion of philosophical implications. New in this edition: - Greater emphasis on molecular biology and intracellular mechanisms - New chapter on genomics and sensory systems - Sections on TRP channels, synaptic transmission, evolution of nervous systems, arachnid mechanosensitive sensilla and photoreceptors, electroreception in the Monotremata, language and the FOXP2 gene, mirror neurons and the molecular biology of pain - Updated passages on human olfaction and gustation. Over four hundred illustrations, boxes containing supplementary material and self-assessment questions and a full bibliography at the end of each part make Biology of Sensory Systems essential reading for undergraduate students of biology, zoology, animal physiology, neuroscience, anatomy and physiological psychology. The book is also suitable for postgraduate students in more specialised courses such as vision sciences, optometry, neurophysiology, neuropathology, developmental biology.

Biology of sensory systems

A comprehensive and highly illustrated text providing a broad and invaluable overview of sensory systems at the molecular, cellular and neurophysiological level of vertebrates, invertebrates and prokaryotes. It retains a strong focus on human systems, and takes an evolutionary and comparative approach to review the mechanosenses, chemosenses, photosenses, and other sensory systems including those for detecting pain, temperature electric and magnetic fields etc. It incorporates exciting and significant new insights provided by molecular biology which demonstrate how similar the molecular architecture and physiology of sensory cells are across species and across sensory modality, often indicationg a common ancestry dating back over half a billion years. Written by a renowned author, with extensive teaching experience in the biology of sensory systems, this book includes: - Over 400 illustrations - Self–assessment questions - Full bibliography preceded by short bibliographical essays - Boxes containing useful supplementary material. It will be invaluable for undergraduates and postgraduates studying biology, zoology, animal physiology, neuroscience, anatomy, molecular biology, physiological psychology and related courses.

A comparative study of life history and gene flow in darters (Pisces: Percidae)

Gene flow, or the exchange of genes between populations, is important because it determines the evolutionary trajectory of a species, including the relative influences of genetic drift and natural selection in the process of population differentiation. Gene flow differs among species because of variation in dispersal capability and abundances across taxa, and historical forces related to geological or lineage history. Both history and ecology influence gene flow in potentially complicated ways, and accounting for their effects remains an important problem in evolutionary biology. This research is a comparative study of gene flow and life-history in a monophyletic group of stream fishes, the darters. As a first step in disentangling historical and ecological effects, I reconstructed the phylogenetic relationships of the study species from nucleotide sequences in the mtDNA control region. I then used this phylogeny and regional glaciation history to infer historical effects on life-history evolution and gene flow in 15 species of darters. Gene flow was estimated indirectly, using information from 20 resolvable and polymorphic allozyme loci. When I accounted for historical effects, comparisons across taxa revealed that gene flow rates were closely associated with differences in clutch sizes and reproductive investment patterns. I hypothesized that differences in larval dispersal among taxa explained this relationship. Results from a field study of larval drift were consistent with this hypothesis. Finally, I asked whether there was an interaction between species' ecology and genetic differentiation across biogeographically distinct regions. Information from allozymes and mtDNA sequences revealed that life history plays an important role in the magnitude of species divergence across biogeographic boundaries. These results suggested an important association between life histories and rates of speciation following an allopatric isolation event. This research, along with other studies from the literature, further illustrates the enormous potential of North American freshwater fishes as a system for studying speciation processes. ^

Taxonomy, ecology, and control of hypsipyla shoot borers of meliaceae

Hypsipyla grandella and Hypsipyla robusta are serious pests of species of the subfamily Swietenioideae of the family Meliaceae in virtually every moist tropical region of the world. An international workshop reviewed the ecology and control of Hypsipyla shoot borers of Meliaceae, identified promising control methods, and set priorities for future research. The conclusions of the workshop are presented with specific recommendations for research in aspects of the taxonomy, biology, and ecology of Hypsipyla, and pest management options that use host plant resistance and chemical, biological, and silvicultural control