High environmental stress and productivity increase functional diversity along a deep‐sea hydrothermal vent gradient

peer reviewedProductivity and environmental stress are major drivers of multiple biodiversity facets and faunal community structure. Little is known on their interacting effects on early community assembly processes in the deep sea (>200 m), the largest environment on Earth. However, at hydrothermal vents productivity correlates, at least partially, with environmental stress. Here, we studied the colonization of rock substrata deployed along a deep‐sea hydrothermal vent gradient at four sites with and without direct influence of vent fluids at 1,700‐m depth in the Lucky Strike vent field (Mid‐Atlantic Ridge [MAR]). We examined in detail the composition of faunal communities (>20 μm) established after 2 yr and evaluated species and functional patterns. We expected the stressful hydrothermal activity to (1) limit functional diversity and (2) filter for traits clustering functionally similar species. However, our observations did not support our hypotheses. On the contrary, our results show that hydrothermal activity enhanced functional diversity. Moreover, despite high species diversity, environmental conditions at surrounding sites appear to filter for specific traits, thereby reducing functional richness. In fact, diversity in ecological functions may relax the effect of competition, allowing several species to coexist in high densities in the reduced space of the highly productive vent habitats under direct fluid emissions. We suggest that the high productivity at fluid‐influenced sites supports higher functional diversity and traits that are more energetically expensive. The presence of exclusive species and functional entities led to a high turnover between surrounding sites. As a result, some of these sites contributed more than expected to the total species and functional β diversities. The observed faunal overlap and energy links (exported productivity) suggest that rather than operating as separate entities, habitats with and without influence of hydrothermal fluids may be considered as interconnected entities. Low functional richness and environmental filtering suggest that surrounding areas, with their very heterogeneous species and functional assemblages, may be especially vulnerable to environmental changes related to natural and anthropogenic impacts, including deep‐sea mining

The power to pardon in late medieval and early modern Europe: New perspectives in the history of crime and criminal justice

Over the past 30 years, few sources have been the subject of more scholarly attention than medieval and early modern pardon letters. These charters, issued by the royal or princely chancery in response to a petition addressed to the monarch and his council, were the strongest manifestation of the sovereign's right to remit crimes in many European polities, including France, England, the Low Countries, Castile, and Portugal. Following the paradigmatic interpretation of ordinary violence as the expression of well‐integrated social behaviours, historians of crime and criminal justice have found in petitions and pardon letters records of powerful narratives describing episodes of violence in the population's everyday life. Yet scholars have also debated the reliability of these stories, as they were obviously designed to support the petitioners' claim for pardon. Another major historiographical controversy concerns the articulation between the power to pardon and the criminal policies of the monarchs. While some historians considered the granting of pardon letters as the product of a weak or corrupted justice system that preferred to remit crimes in exchange for money rather prosecuting the perpetrators, others argued that the rise of the power to pardon followed the process of early modern State‐building and served to temper criminal prosecutions and assert the sovereign's right over the life and death of his subjects. This essay introduces the reader to the historiography of pardon letters and shows its connections with the recent developments in the history of crime and criminal justice in late medieval and early modern Europe