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Successional dynamics can vary because of a range of ecological and environmental factors, but our understanding of biogeographic variation in succession, and the processes contributing to community development across ecosystems, is limited. The pattern and rate of recruitment of dispersive propagules likely differs over large spatial scales and can be an important predictor of successional trajectory. Over a 20° tropical-temperate latitudinal gradient, we measured sessile invertebrates over 12 months of community development and successive 3-month recruitment windows to understand succession and how it is influenced by recruitment. Succession and recruitment patterns varied over latitude. In the tropics, fast temporal turnover, fluctuating abundances, and lack of successional progression suggest that the contribution of stochastic processes was high. As latitude increased, successional progression became more apparent, characterized by increasing species richness and community cover and a shift to more competitive taxa over time. At temperate locations, species identities were similar between older communities and recruiting assemblages; however, community composition became more variable across space over time. Such divergence suggests an important role of early colonizers and species interactions on community structure. These findings demonstrate differences in the processes contributing to community development and biodiversity patterns over latitude. Understanding such biogeographic variation in community dynamics and identifying the prevalence of different processes can provide insights into how communities assemble and persist in response to environmental variability. [ABSTRACT FROM AUTHOR]

Student evaluations of teaching (SET) have been examined over the years to better understand the student experience, with an increasing portion of literature exploring the presence of implicit bias in SET surveys against minority gender and ethnic lecturers. This study explores free-text comments made by students from a large public university in Australia over the period 2010-2016, using a semi-supervised statistical approach. Data were collected via surveys administered online at the end of each course to every student officially enrolled in that course via the learning management system, and completion of the surveys was voluntary. We build a probabilistic topic model which incorporates student and lecturer characteristics into the topic formation process. We make statistical inference on the effects of gender and cultural or language backgrounds based on the topic and word prevalence probabilities. The results showed clear separation of topics discussed betweenmale and female lecturers. From a gendered perspective, our topic analyses have found that students are significantly more likely to critique female lecturers to improve on structural aspects of the course, as well as aspects of time management and control of the lecturing environment. In comparison, male lecturers were significantlymore likely to be critiqued on specific aspects related to lecture delivery. Lecturers from non-English speaking backgrounds were more likely to be both critiqued and praised for the clarity of their delivery. [ABSTRACT FROM AUTHOR]

Context. Diseases have affected coral populations worldwide, leading to population declines and requiring active restoration efforts. Aims. Describe population and individual impacts of necrotising disease in the Endangered octocoral Dendronephthya australis. Methods. We quantified population loss and recruitment by using reference photos, survey and GPS mapping and described disease lesions by using histopathology. Key results. From December 2019 to January 2020, we observed polyp loss, necrotic lesions and loss of large colonies of D. australis at Botany Bay, New South Wales, Australia. By September 2020, only a few scattered recruits remained, and all large colonies were lost. Histopathology of colonies sampled in January 2020 confirmed that the disease had resulted in necrosis, gastrovascular canal collapse and internal colony integrity loss, leading to mortality. New recruits were recorded within 10 months of disease onset, and large colonies within 18 months. Conclusions. Although the necrotising disease had significant impacts on both the individual and population level, natural recruitment began quickly. As such, unlike in other populations, restoration is not currently required in the Bare Island D. australis population. Implications. The extent of disease impact at the individual and population levels suggests that monitoring for lesions should be undertaken before developing conservation and restoration strategies for this species. [ABSTRACT FROM AUTHOR]

The influence of habitat complexity on biodiversity is a central theme in ecology, with many studies reporting positive relationships. Reconciliation approaches in urbanised areas, such as eco‐engineering, have increasingly focused on 're‐building' the complexity of degraded and/or homogenised habitats to support biodiversity. Yet, the effects of increasing complexity and biodiversity on ecological functions are rarely measured.We assessed how increasing the physical and/or biogenic complexity of habitats affects the net primary productivity (NPP) and gross primary productivity (GPP), community respiration and nutrient cycling (specifically dissolved inorganic phosphorus and nitrogen) of intertidal sessile marine communities at three sites. We manipulated physical complexity using two types of settlement tiles: 'complex', with crevices and ridges, and 'flat'. We increased biogenic complexity on half the replicates of each tile type by seeding with oysters.Increased physical and biogenic complexity resulted in greater sessile species richness at all sites. Although many variables assessed varied with sites and time of measurements, overall, GPP and NPP were greater on flat tiles than on complex ones. These patterns were not explained by differences in the total surface area of tiles.Daily flux rates of dissolved inorganic phosphorus had a significant positive relationship with biogenic complexity. There were no effects of biogenic or physical complexity on the net fluxes of dissolved inorganic nitrogen.Effects of habitat complexity on the productivity and nutrient cycling of marine sessile communities were largely unrelated to diversity measures, such as richness or abundance of key taxa and functional groups.Synthesis and applications. Eco‐engineering practices that manipulate habitat complexity might benefit from explicit functional targets that also consider associated ecosystem services, as we found that under some conditions there is a trade‐off between biodiversity and functional targets. Our results suggest that increasing habitat complexity has a positive effect on sessile species richness, but not necessarily on productivity (GPP and NPP). The species pool available as well as light availability is likely to mediate effects of complexity on assemblages, so local environment needs to be a key consideration when designing interventions. [ABSTRACT FROM AUTHOR]