New Political Parties as Innovators - Formation and Success

This cumulative dissertation investigates the formation and success of new political parties in developed democracies from the perspective of the programmatic competition between parties (see. introduction in chapter 1). It starts by arguing that the current state of the programmatic supply by existing parties is a central determinant for the likelihood of new party formation (chapter 2). A low programmatic diversity of existing parties creates scope for programmatic innovations by new parties. The dissertation establishes a connection between the literature on new parties and niche parties by analyzing the latter as typical cases of innovating new parties (chapter 3). For this purpose, the author combines two concepts with corresponding measures in order to capture the programmatic profiles of parties. Nicheness refers to differences in the emphasis of topics between a given party and its counterparts while programmatic concentration shows the narrowness of a given policy profile. Chapter 4 investigates how the variation in the programmatic profiles of niche parties affect their long-term electoral performance. Previous studies on niche parties have not fully taken into account the evolutionary aspect of the programmatic profiles of these parties. Acknowledging the variation in programmatic profiles between niche parties and over time, the article argues that the electoral effects of nicheness and programmatic concentration as programmatic features of niche parties vary over their lifecycle. The literature on new parties assumes that they can benefit from the poor representation of parts of the electorate by existing parties. This strand of research provides plausible results, but it operates on the macro level, which is problematic for theoretical and methodological reasons. The study in chapter 5 overcomes these problems through a multilevel analysis of the vote choice between new parties, existing parties and abstention.

Phylum-wide transcriptome analysis of oogenesis and early embryogenesis in selected nematode species

Oogenesis is a prerequisite for embryogenesis in Metazoa. During both biological processes important decisions must be made to form the embryo and hence ensure the next generation: (1) Maternal gene products (mRNAs, proteins and nutrients) must be supplied to the embryo. (2) Polarity must be established and axes must be specified. While incorporation of maternal gene products occurs during oogenesis, the time point of polarity establishment and axis specification varies among species, as it is accomplished either prior, during, or after fertilisation. But not only the time point when these events take place varies among species but also the underlying mechanisms by which they are triggered. For the nematode model Caenorhabditis elegans the underlying pathways and gene regulatory networks (GRNs) are well understood. It is known that there the sperm entry point initiates a primary polarity in the 1-celled egg and with it the establishment of the anteroposterior axis. However, studies of other nematodes demonstrated that polarity establishment can be independent of sperm entry (Goldstein et al., 1998; Lahl et al., 2006) and that cleavage patterns, symmetry formation and cell specification also differ from C. elegans. In contrast to the studied Chromadorea (more derived nematodes including C. elegans), embryos of some marine Enoplea (more basal representatives) even show no discernible early polarity and blastomeres can adopt variable cell fates (Voronov and Panchin 1998). The underlying pathways controlling the obviously variant embryonic processes in non-Caenorhabditis nematodes are essentially unknown. In this thesis I addressed this issue by performing a detailed unbiased comparative transcriptome analysis based on microarrays and RNA sequencing of selected developmental stages in a variety of nematodes from different phylogenetic branches with C. elegans as a reference system and a nematomorph as an outgroup representative. In addition, I made use of available genomic data to determine the presence or absence of genes for which no expression had been detected. In particular, I focussed on components of selected pathways or GRNs which are known to play essential roles during C. elegans development and/or other invertebrate or vertebrate model systems. Oogenesis must be regulated differently in non-Caenorhabditis nematodes, as crucial controlling components of Wnt and sex determination signaling are absent in these species. In this respect, I identified female-specific expression of potential polarity associated genes during gonad development and oogenesis in the Enoplean nematode Romanomermis culicivorax. I could show that known downstream components of the polarity complexes PAR-3/-6/PKC-3 and PAR-1/-2 are absent in non-Caenorhabditis species. Even PAR-2 as part of the polarity complex does not exist in these nematodes. Instead, transcriptomes of nematodes (including C. elegans), show expression of other polarity-associated complexes such as the Lgl (Lethal giant larvae) complex. This result could pose an alternative route for nematodes and nematomorphs to initiate polarity during early embryogenesis. I could show that crucial pathways of axis specification, such as Wnt and BMP are very different in C. elegans compared to other nematodes. In the former, Wnt signaling, for instance, is mediated by four paralogous beta-catenins, while other Chromadorea have fewer and Enoplea only one beta-catenin. The transcriptomes of R. culicivorax and the nematomorph show that regulators of BMP (e.g. Chordin), are specifically expressed during early embryogenesis only in Enoplea and the close outgroup of nematomorphs. In conclusion, my results demonstrate that the molecular machinery controlling oogenesis and embryogenesis in nematodes is unexpectedly variable and C. elegans cannot be taken as a general model for nematode development. Under this perspective, Enoplean nematodes show more similarities with outgroups than with C. elegans. It appears that certain pathway components were lost or gained during evolution and others adopted new functions. Based on my findings I can conjecture, which pathway components may be ancestral and which were newly acquired in the course of nematode evolution.