Dispersal syndrome and landscape fragmentation in the salt-marsh specialist spider Erigone longipalpis

Dispersal and its evolution play a key role for population persistence in fragmented landscapes where habitat loss and fragmentation increase the cost of between-habitat movements.In such contexts,it is important to know how variation in dispersal and other traits is structured,and whether responses to landscape fragmentation are aligned with underlying dispersal-trait correlations,or dispersal syndromes.We,therefore,studied trait variation in Erigone longipalpis,a European spider species specialist of(often patchy)salt marshes.We collected spiders in two salt-marsh landscapes differing in habitat availability.We then reared lab-born spiders for two generations in controlled conditions,and measured dispersal and its association with various key traits.Erigone longipalpis population densities were lower in the more fragmented landscape.Despite this,we found no evidence of differences in dispersal,or any other trait we studied,between the two landscapes.While a dispersal syndrome was present at the among-individual level(dispersers were more fecund and faster growing,among others),there was no indication it was genetically driven:among-family differences in dispersal were not correlated with differences in other traits.Instead,we showed that the observed phenotypic covariations were mostly due to within-family correlations.We hypothesize that the dispersal syndrome is the result of asymmetric food access among siblings,leading to variation in development rates and carrying over to adult traits.Our results show we need to better understand the sources of dispersal variation and syndromes,especially when dispersal may evolve rapidly in response to environmental change.

Editorial

Dear All,It is with great pleasure that we welcome you to the first issue of our journal,PUQR–Probability,Uncertainty and Quantitative Risk,a peer-reviewed openaccess journal.Considering its recent and very dynamic development,the theory of backward stochastic differential equations has attracted many researchers,with its vast field of applications in stochastic control,games,finance,and deterministic and stochastic partial differential equations.This has spurred the development of new areas for research such as nonlinear dynamic expectation theory,e.g.,g and G-expectation,and path-dependent partial differential equations,while also finding new applications for problems of ambiguity,uncertainty,quantitative risk,and recursive utility in finance and economics.As we further this field,it is important to provide a forum to stimulate future development with a journal that focuses on these topics.More precisely。

Expert group syndrome at high altitude

During a training session for the university diploma of Mountain medicine delivered by University Sorbonne Paris Nord for medical doctors,one of the participants developed signs of maladaptation to high altitude at 3600 m,the severity of which was incorrectly interpreted.Information was sparingly given by the patient(an anesthetist)to several of his colleagues and no one was in charge to collect clinical data,take a history,and provide appropriate treatment.The combination of the absence of designation of a supervising doctor and the difficulty of communicating with the patient led to a lack of coordinated management and to an evolution of the symptoms towards severe acute mountain sickness.Fortunately,the very rapid management of the patient and a rapid helicopter evacuation,as soon as the symptoms worsened towards the onset of a suspected high altitude cerebral and/or pulmonary edema,allowed rapid resolution without sequelae.Environmental,medical,psychological,and managerial factors led to this Expert Group Syndrome.