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Sipunculans (also known as peanut worms) are an ancient group of exclusively marine worms with a global distribution and a fossil record that dates back to the Early Cambrian. The systematics of sipunculans, now considered a distinct subclade of Annelida, has been studied for decades using morphological and molecular characters, and has reached the limits of Sanger-based approaches. Here, we reevaluate their family-level phylogeny by comparative transcriptomic analysis of eight species representing all known families within Sipuncula. Two data matrices with alternative gene occupancy levels (large matrix with 675 genes and 62% missing data; reduced matrix with 141 genes and 23% missing data) were analysed using concatenation and gene-tree methods, yielding congruent results and resolving each internal node with maximum support. We thus corroborate prior phylogenetic work based on molecular data, resolve outstanding issues with respect to the familial relationships of Aspidosiphonidae, Antillesomatidae and Phascolosomatidae, and highlight the next area of focus for sipunculan systematics.

In just the last ten years, a growing number of states have sought to join the race to develop and sell ever-more sophisticated drones on the global market. While today the market remains stratified between makers and takers of drones, the gradual emergence of a drones arms race will have some important and potentially dangerous consequences for the international system. The emergence of a race for drones will reshape long-simmering conflicts and rivalries around the world in three ways. First, the proliferation of drones will reset the rules and norms governing surveillance and reconnaissance. Second, drones will become increasingly useful to governments in testing the strategic commitments and the nerves of their rivals. Third, the worldwide proliferation of drones will multiply the risks of conflict spirals stemming from accidents or hijacked drones. Given these risks, Washington’ should take a leading role in slowing the global race for drones and in developing strict legal and normative mechanisms to govern drone usage and sales in the future.

FoxC, FoxF, FoxL1 and FoxQ1 genes have been shown to be clustered in some animal genomes, with mesendodermal expression hypothesised as a selective force maintaining cluster integrity. Hypotheses are, however, constrained by a lack of data from the Lophotrochozoa. Here we characterise members of the FoxC, FoxF, FoxL1 and FoxQ1 families from the annelid Capitella teleta and the molluscs Lottia gigantea and Patella vulgata. We cloned FoxC, FoxF, FoxL1 and FoxQ1 genes from C. teleta, and FoxC, FoxF and FoxL1 genes from P. vulgata, and established their expression during development. We also examined their genomic organisation in C. teleta and L. gigantea, and investigated local syntenic relationships. Our results show mesodermal and anterior gut expression is a common feature of these genes in lophotrochozoans. In L. gigantea FoxC, FoxF and FoxL1 are closely linked, while in C. teleta Ct-foxC and Ct-foxL1 are closely linked, with Ct-foxF and Ct-foxQ1 on different scaffolds. Adjacent to these genes there is limited evidence of local synteny. This demonstrates conservation of genomic organisation and expression of these genes can be traced in all three bilaterian Superphyla. These data are evaluated against competing theories for the long-term maintenance of gene clusters.

What explains variations in violence in post-conflict states? Within the existing literature, violence in post-conflict states is portrayed simply as a threat to an existing peace settlement and is explained by referring to either the legacy of the war (that is, the death and destruction caused by the war itself) or by the legacy of the peace (that is, the nature of the peace settlement). Using a medium-n dataset of fifty four post-conflict states from 1989-2007, this paper will traces variations in violence for five years following the termination of the war, using five different sources of data per year. It finds that post-conflict states, even those that do not relapse into war, feature significant variations in incidence, magnitude, type and target of attack. Even states that are described as stable and peaceful in the existing literature have a range of violent acts, including both strategic and criminal violence, which can have a significant political effect and erode confidence in the peace settlement. More specifically, it also finds that neither explanations focusing on the legacy of the war or peace are sufficient to account for the variations in strategic violence. Drawing on recent work focusing on the organizational dimensions of armed groups (Kalyvas 2006, Weinstein 2007), it develops a theory for explaining the variation in strategic violence based on the capacity of leaders of armed organizations to manage the risks of organizational dissolution through the provision of domestic rewards and in-group policing. It concludes by specifying the mechanisms in which distributional and policing failures generate or facilitate mobilization by new or latent claimants to power in post-conflict states.