Virgin birth in a hammerhead shark.

Parthenogenesis has been documented in all major jawed vertebrate lineages except mammals and cartilaginous fishes (Class Chondrichthyes: sharks, batoids, chimeras). Reports of captive female sharks giving birth despite being held in the extended absence of males have generally been ascribed to prior matings coupled with long-term sperm storage by the females. Here we provide the first genetic evidence for chondrichthyan parthenogenesis, involving a hammerhead shark. This finding also broadens the known occurrence of a specific type of asexual development (automictic parthenogenesis) among vertebrates, extending recently raised concerns about the potential negative effect of this type of facultative parthenogenesis on the genetic diversity of threatened vertebrate species.

The Region between State and Nation: British and Irish conceptions of Northern Ireland as a European Region

This article investigates the concept of regionalism in the EU and its relationship to changing conceptions of the nation-statehood in Ireland and Britain. More specifically, it examines how the notion of regionalism has developed in official discourse during states' adaptation to both internal challenges and the process of European integration. I explore this question through an analysis of the British and Irish state elites approaches to the Northern Ireland conflict and their perceptions of European regionalism in this context. In identifying the differences and, indeed, similarities between these states' approaches to European and regional dynamics, I develop new perspective on post-Agreement Northern Ireland and the concept of multilevel governance.