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The PREDICTS project-Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)-has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.

Rock-dwelling land snails, feeding on algae and lichens that grow on stone surfaces, may influence the structure and function of these ecosystems. Yet, little is known about the life history of rock-dwelling snails. We performed a 30-month mark-release-resight study in four populations of Chondrina clienta (Westerlund, 1883) inhabiting vertical walls of abandoned limestone quarries on the Baltic island of Oland, Sweden, to assess growth rate and survival of juvenile snails and determine age at maturity. We marked 800 individuals ranging in shell height from 1.4 to 4.9 mm, released them in their original habitat, and remeasured their shell height at intervals of 6 months. Shell growth of juvenile C. clienta was affected by the site (quarry wall) and the size of the individual, being highest in medium-sized snails. Shell growth occurred during both summer and winter. Annual apparent survival rates of C. clienta were size-dependent and ranged from 58.6% to 96.3%. Sexual maturity was reached at an age of 5 years, which is later than in most large snail species. Our study extends current knowledge on life history of land snails to a rarely studied group dwelling on rock surfaces. Key words: age at maturity, annual survival rate, Chondrina clienta, individual growth, life history, rock-dwelling land snail, terrestrial gastropod. Si les escargots terrestres vivant sur la roche et se nourrissant d'algues et de lichens sur les surfaces rocheuses peuvent influencer la structure et la fonction de ces ecosystemes, les connaissances sur le cycle biologique de ces animaux sont pourtant tres limitees. Nous avons mene une etude consistant a marquer, relacher, puis reexaminer des individus sur une periode de 30 mois dans quatre populations de Chondrina clienta (Westerlund, 1883) vivant sur les parois verticales de carrieres de calcaire abandonnees dans l'ile balte d'Oland (Suede), afin d'evaluer le taux de croissance et la survie d'escargots juveniles et de determiner leur age a la maturite. Nous avons marque 800 individus dont les hauteurs de la coquille allaient de 1,4 a 4,9 mm, les avons ensuite relaches dans leur habitat d'origine, puis remesure la hauteur de leur coquille tous les 6 mois. La croissance de la coquille de C. clienta juveniles variait selon le site (paroi de la carriere) et la taille de l'individu, le taux de croissance etant le plus eleve pour les escargots de taille moyenne. La croissance de la coquille s'effectuait tant l'ete que l'hiver. Les taux annuels de survie apparente de C. clienta dependaient de la taille et allaient de 58,6 % a 96,3 %. La maturite sexuelle etait atteinte a l'age de 5 ans, soit plus tard que pour la plupart des especes d'escargot de grande taille. Notre etude elargit les connaissances actuelles sur le cycle biologique des escargots terrestres a un groupe rarement etudie qui vit sur les surfaces rocheuses. [Traduit par la Redaction] Mots-cles : age a la maturite, taux de survie annuel, Chondrina clienta, croissance individuelle, cycle biologique, escargot terrestre vivant sur la roche, gasteropode terrestre., Introduction Growth is an important life-history process, influencing a range of later fitness-related traits such as age and size at maturity and total reproductive output (Stearns 1992; Charnov 2004; English [...]

Knowledge of patterns of genetic diversity in populations of threatened species is vital for their effective conservation. However, destructive sampling should be avoided in threatened species so as not to additionally increase the risk of local population extinction. We exclusively used beetle remains and beetles collected after death to analyze local and regional patterns of genetic variation in the endangered flightless longhorn beetle Iberodorcadion fuliginator in the border region of Switzerland, France and Germany, in grassland remnants. We extracted DNA from the beetles' remains and genotyped 243 individuals at 6 microsatellite loci. We found moderate genetic differentiation between populations, each belonging to one of two metapopulations situated on either side of the river Rhine, but distinct genetic differentiation between populations across metapopulation. The genetic distance between populations was correlated with the geographic distance between the sites sampled. Genetic structure analysis inferred the presence of two genetic clusters. The populations in the Alsace (France) represent one cluster, together with the Swiss populations near Basel, which is separated by the river Rhine from the cluster composed of the populations in southwestern Germany. Thus, the historical separation by the river Rhine surpasses more recent effects of human-induced habitat fragmentation on the genetic differentiation in I. fuliginator. [ABSTRACT FROM AUTHOR]