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Captive reptiles are routinely identified as reservoirs of pathogenic bacteria and reports of reptile-associated infections relating to some species are well documented (e.g., salmonellosis). Currently, relatively little is known about the epidemiology and bacteria of ball pythons. We carried out a survey of ball python farms in Togo, West Africa to assess the presence of any potentially pathogenic bacterial taxa that have been identified in recent scientific literature relating to this species. The presence of bacteria belonging to the genera Acinetobacter, Bacteroides, Citrobacter, Enterobacter, Lysobacter, Proteus, Pseudomonas, Staphylococcus, and Tsukamurella in oral and cloacal samples taken from five individual ball pythons is of potential concern for horizontal transmission given that pathogenic species belonging to these genera have been previously documented. The presence of bacteria belonging to the genera Clostridium, Escherichia, Moraxella, and Stenotrophomonas in the oral and rectal samples taken from five mice used to feed ball pythons suggests that they represent a potential reservoir of infection for wild caught ball pythons and their progeny. Furthermore, possible sources of environmental contamination include other captive amphibians, birds, reptiles and mammals, as well as free ranging birds and small mammals. Additional surveillance of ball pythons in the wild and in captivity at python farms in West Africa will shed light on whether or not this type of commercial activity is increasing pathogen exposure and lowering barriers to transmission. Meanwhile, as a precautionary measure, it is recommended that python farms should immediately establish biosecurity and disease surveillance practices to minimize potential horizontal and vertical bacterial transfer.

Diversity among species and genetic diversity within species are both important components of ecological communities that can determine the outcome of species interactions, especially between hosts and parasites. We sought to understand the impact of species diversity on host community resistance to infection by a keystone parasitic plant (Rhinanthus minor L.) and genetic diversity of the parasite on its successful establishment in a grassland community. We used an experimental approach where large pots were planted with mixtures of mesotrophic grassland species at high and low species diversity. The parasitic plant was sown in a proportion of these with high and low genetic diversity treatments. Establishment of the parasite was monitored over 2 years and the pots harvested at the end of each growing season to determine the impact of infection on plant community biomass. We found a strong effect of host plant species diversity on the establishment of the parasitic plant, with successful establishment considerably lower in the high species diversity treatment. Genetic diversity appeared to promote establishment of the parasite in the high species diversity treatment, and also facilitated longer term fitness in the low species diversity treatment. Host community structure was influenced by R. minor, with grass relative biomass decreasing and legume relative biomass increasing when the parasite was present. There was no direct impact of the presence of the parasite on the relative biomass of nonleguminous forbs. Synthesis. Our data demonstrate the importance of host community species diversity in deterring the establishment of a generalist parasite. They also highlight the role of genetic diversity in determining the outcome of host–parasite interactions in multispecies communities. These findings, therefore, have important implications for the establishment and management of species‐rich grasslands and provide insight into the community dynamics of parasitic plants a

The emergence of high-throughput DNA sequencing methods provides unprecedented opportunities to further unravel bacterial biodiversity and its worldwide role from human health to ecosystem functioning. However, despite the abundance of sequencing studies, combining data from multiple individual studies to address macroecological questions of bacterial diversity remains methodically challenging and plagued with biases. Here, using a machine-learning approach that accounts for differences among studies and complex interactions among taxa, we merge 30 independent bacterial data sets comprising 1,998 soil samples from 21 countries. Whereas previous meta-analysis efforts have focused on bacterial diversity measures or abundances of major taxa, we show that disparate amplicon sequence data can be combined at the taxonomy-based level to assess bacterial community structure. We find that rarer taxa are more important for structuring soil communities than abundant taxa, and that these rarer taxa are better predictors of community structure than environmental factors, which are often confounded across studies. We conclude that combining data from independent studies can be used to explore bacterial community dynamics, identify potential ‘indicator’ taxa with an important role in structuring communities, and propose hypotheses on the factors that shape bacterial biogeography that have been overlooked in the past.

The emergence of high-throughput DNA sequencing methods provides unprecedented opportunities to further unravel bacterial biodiversity and its worldwide role from human health to ecosystem functioning. However, despite the abundance of sequencing studies, combining data from multiple individual studies to address macroecological questions of bacterial diversity remains methodically challenging and plagued with biases. Here, using a machine-learning approach that accounts for differences among studies and complex interactions among taxa, we merge 30 independent bacterial data sets comprising 1,998 soil samples from 21 countries. Whereas previous meta-analysis efforts have focused on bacterial diversity measures or abundances of major taxa, we show that disparate amplicon sequence data can be combined at the taxonomy-based level to assess bacterial community structure. We find that rarer taxa are more important for structuring soil communities than abundant taxa, and that these rarer taxa are better predictors of community structure than environmental factors, which are often confounded across studies. We conclude that combining data from independent studies can be used to explore bacterial community dynamics, identify potential ‘indicator’ taxa with an important role in structuring communities, and propose hypotheses on the factors that shape bacterial biogeography that have been overlooked in the past.

For feedback to be effective, it must be used by the receiver. Prior research has outlined numerous reasons why students’ use of feedback is sometimes limited, but there has been little systematic exploration of these barriers. In 11 activity-oriented focus groups, 31 undergraduate Psychology students discussed how they use assessment feedback. The data revealed many barriers that inhibit use of feedback, ranging from students’ difficulties with decoding terminology, to their unwillingness to expend effort. Thematic analysis identified four underlying psychological processes: awareness, cognisance, agency, and volition. We argue that these processes should be considered when designing interventions to encourage students’ engagement with feedback. Whereas the barriers identified could all in principle be removed, we propose that doing so would typically require—or would at least benefit from—a sharing of responsibility between teacher and student. The data highlight the importance of training students to be proactive receivers of feedback.

Background and Aims Successful cryopreservation of bryophytes is linked to intrinsic desiccation tolerance and survival can be enhanced by pre-treatment with abscisic acid (ABA) and sucrose. The pioneer moss Ditrichum plumbicola is naturally subjected to desiccation in the field but showed unexpectedly low survival of cryopreservation, as well as a poor response to pre-treatment. The effects of the cryopreservation protocol on protonemata of D. plumbicola were investigated in order to explore possible relationships between the production in vitro of cryopreservation-tolerant asexual propagules and the reproductive biology of D. plumbicola in nature. Methods Protonemata were prepared for cryopreservation using a four-step protocol involving encapsulation in sodium alginate, pre-treatment for 2 weeks with ABA and sucrose, desiccation for 6 h and rapid freezing in liquid nitrogen. After each stage, protonemata were prepared for light and electron microscopy and growth on standard medium was monitored. Further samples were prepared for light and electron microscopy at intervals over a 24-h period following removal from liquid nitrogen and re-hydration. Key Results Pre-treatment with ABA and sucrose caused dramatic changes to the protonemata. Growth was arrested and propagules induced with pronounced morphological and cytological changes. Most cells died, but those that survived were characterized by thick, deeply pigmented walls, numerous small vacuoles and lipid droplets in their cytoplasm. Desiccation and cryopreservation elicited no dramatic cytological changes. Cells returned to their pre-dehydration and cryopreservation state within 2 h of re-hydration and/or removal from liquid nitrogen. Regeneration was normal once the ABA/sucrose stimulus was removed. Conclusions The ABA/sucrose pre-treatment induced the formation of highly desiccation- and cryopreservation-tolerant propagules from the protonemata of D. plumbicola. This parallels behaviour in the wild, where hig