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The reduction in coral cover on many contemporary tropical reefs suggests a different set of coral community assemblages will dominate future reefs. To evaluate the capacity of reef corals to persist over various time scales, we examined coral community dynamics in contemporary, fossil, and simulated future coral reef ecosystems. Based on studies between 1987 and 2012 at two locations in the Caribbean, and between 1981 and 2013 at five locations in the Indo-Pacific, we show that many coral genera declined in abundance, some showed no change in abundance, and a few coral genera increased in abundance. Whether the abundance of a genus declined, increased, or was conserved, was independent of coral family. An analysis of fossil-reef communities in the Caribbean revealed changes in numerical dominance and relative abundances of coral genera, and demonstrated that neither dominance nor taxon was associated with persistence. As coral family was a poor predictor of performance on contemporary reefs, a trait-based, dynamic, multi-patch model was developed to explore the phenotypic basis of ecological performance in a warmer future. Sensitivity analyses revealed that upon exposure to thermal stress, thermal tolerance, growth rate, and longevity were the most important predictors of coral persistence. Together, our results underscore the high variation in the rates and direction of change in coral abundances on contemporary and fossil reefs. Given this variation, it remains possible that coral reefs will be populated by a subset of the present coral fauna in a future that is warmer than the recent past.

Introduction The arrival and establishment of marine non-indigenous species can have dramatic effects on the structure and functioning of coastal ecosystems (Galil 2007; Wallentinus and Nyberg 2007; Ehrenfeld 2010). Early [...]

This open-access special issue features 12 full articles representing emerging trends from the international DNA barcoding community. Several articles highlight how DNA-based techniques are elucidating the species diversity, biogeography, and [...]

The Sahara desert is the largest warm desert in the world and a poorly explored area. Small water-bodies occur across the desert and are crucial habitats for vertebrate biodiversity. Environmental DNA (eDNA) is a powerful tool for species detection and is being increasingly used to conduct biodiversity assessments. However, there are a number of difficulties with sampling eDNA from such turbid water-bodies and it is often not feasible to rely on electrical tools in remote desert environments. We trialled a manually powered filtering method in Mauritania, using pre-filtration to circumvent problems posed by turbid water in remote arid areas. From nine vertebrate species expected in the water-bodies, four were detected visually, two via metabarcoding, and one via both methods. Difficulties filtering turbid water led to severe constraints, limiting the sampling protocol to only one sampling point per study site, which alone may largely explain why many of the expected vertebrate species were not detected. The amplification of human DNA using general vertebrate primers is also likely to have contributed to the low number of taxa identified. Here we highlight a number of challenges that need to be overcome to successfully conduct metabarcoding eDNA studies for vertebrates in desert environments in Africa.Key words: eDNA, spike, Mauritania, vertebrate, turbid, desert, biodiversity.Le desert du Sahara est le plus chaud au monde et constitue une region peu exploree. De petits plans d'eau sont presents dans le desert et sont des habitats cruciaux pour la biodiversite des vertebres. L'ADN environnemental (ADNe) est un outil puissant pour la detection des especes et il est de plus en plus employe pour realiser des mesures de la biodiversite. Cependant, il existe plusieurs difficultes liees a l'echantillonnage de l' ADNe au sein de tels plans d'eau troubles et il est souvent impossible d'avoir recours a des outils electriques dans des environnements desertiques isoles. Les auteurs ont mis a l'essai une methode de filtration manuelle en Mauritanie et ont fait appel a une pre-filtration pour contourner les problemes lies a l'eau trouble dans les regions arides eloignees. Des neuf especes de vertebres attendues au sein des plans d'eau, quatre ont ete detectees visuellement, deux via meta-codage a barres et une via les deux approches. Des difficultes liees a la filtration de l'eau trouble ont entraine de nombreuses contraintes, limitant le protocole d'echantillonnage a un seul par site ce qui peut expliquer que plusieurs des especes attendues n'aient pas ete detectees. L'amplification d'ADN humain a l'aide d'amorces generiques pour vertebres pourrait aussi avoir contribue au faible nombre de taxons identifies. Dans ce travail, les auteurs soulignent plusieurs defis qu'il faudra surmonter pour realiser avec succes des etudes de meta-codage a barres de l' ADNe chez les vertebres dans les environnements desertiques de l'Afrique. [Traduit par la Redaction]Mots-cles: ADNe, doper, Mauritanie, vertebre, trouble, desert, biodiversite., IntroductionKnowledge on species distribution is essential in many fields of biology, and the identification of areas with high species richness is crucial to protect global and regional hotspots of biodiversity [...]

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