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Cooperatively breeding species exhibit a range of social behaviours associated with different costs and benefits to group living, often in association with different environmental conditions. For example, recent phylogenetic studies have collectively shown that the evolution and distribution of cooperative breeding behaviour is related to the environment. However, little is known about how environmental variation may drive differences in social systems across populations within species, and how the relationship between environmental conditions and sociality may differ across species. Here, we examine variation in social group size along a steep environmental gradient for two congeneric cooperatively breeding species of fairywrens (Maluridae) and show that they exhibit opposing ecogeographic patterns. Purple-backed fairywrens, a species in which helpers increase group productivity, have larger groups in hot, dry environments and smaller groups in cool, wet environments. By contrast, superb fairywrens, a species with helpers that do not increase group productivity despite the presence of alloparental care, exhibit the opposite trend. We suggest differences in the costs and benefits of sociality contribute to these opposing ecogeographical patterns and demonstrate that comparisons of intraspecific patterns of social variation across species can provide insight into how ecology shapes social systems. 

Abstract Avian mixed-species flocks are ubiquitous across habitats and a model for studying how heterospecific sociality influences the behavior and composition of animal communities. Here, we review the literature on mixed-species flocks and argue that a renewed focus on individual-level interactions among flock members can transform our understanding of this iconic, avian social system. Specifically, we suggest that an individual perspective will further our understanding of (1) how inter- and intraspecific variation in flock participation links to fitness costs and benefits, (2) the implications of familiarity between individuals in structuring mixed-species flock communities, and (3) how social roles within mixed-species flocks are related to social behavior within and across species. We summarize studies that use an individual perspective in each of these areas and discuss knowledge from conspecific social behavior to posit more broadly how individuals may shape mixed-species flocks. We encourage research approaches that incorporate individual variation in traits, relationships, and social roles in their assessment of mixed-species flocking dynamics. We propose that the analysis of individual variation in behavior will be particularly important for explicitly identifying fitness outcomes that led to the evolution of mixed-species flocks, which in turn affect community structure and resilience. 

Nitrogen fixers (diazotrophs) are often an important nitrogen source to phytoplankton nutrient budgets in N-limited marine environments. Diazotrophic symbioses between cyanobacteria and diatoms can dominate nitrogen-fixation regionally, particularly in major river plumes and in open ocean mesoscale blooms. This study reports the successful isolation and growth in monocultures of multiple strains of a diatom-cyanobacteria symbiosis from the Gulf of Mexico using a modified artificial seawater medium. We document the influence of light and nutrients on nitrogen fixation and growth rates of the host diatom Hemiaulus hauckii Grunow together with its diazotrophic endosymbiont Richelia intracellularis Schmidt, as well as less complete results on the Hemiaulus membranaceus - R. intracellularis symbiosis. The symbioses rates reported here are for the joint diatom-cyanobacteria unit. Symbiont diazotrophy was sufficient to support both the host diatom and cyanobacteria symbionts, and the entire symbiosis replicated and grew without added nitrogen. Maximum growth rates of multiple strains of H. hauckii symbioses in N-free medium with N 2 as the sole N source were 0.74–0.93 div d −1 . Growth rates followed light saturation kinetics in H. hauckii symbioses with a growth compensation light intensity (E C ) of 7–16 µmol m −2 s −1 and saturation light level (E K ) of 84–110 µmol m −2 s −1 . Nitrogen fixation rates by the symbiont while within the host followed a diel pattern where rates increased from near-zero in the scotophase to a maximum 4–6 h into the photophase. At the onset of the scotophase, nitrogen-fixation rates declined over several hours to near-zero values. Nitrogen fixation also exhibited light saturation kinetics. Maximum N 2 fixation rates (84 fmol N 2 heterocyst −1 h −1 ) in low light adapted cultures (50 µmol m −2 s − 1) were approximately 40–50% of rates (144–154 fmol N 2 heterocyst −1 h −1 ) in high light (150 and 200 µmol m −2 s −1 ) adapted cultures. Maximum laboratory N 2 fixation rates were ~6 to 8-fold higher than literature-derived field rates of the H. hauckii symbiosis. In contrast to published results on the Rhizosolenia-Richelia symbiosis, the H. hauckii symbiosis did not use nitrate when added, although ammonium was consumed by the H. hauckii symbiosis. Symbiont-free host cell cultures could not be established; however, a symbiont-free H. hauckii strain was isolated directly from the field and grown on a nitrate-based medium that would not support DDA growth. Our observations together with literature reports raise the possibility that the asymbiotic H. hauckii are lines distinct from an obligately symbiotic H. hauckii line. While brief descriptions of successful culture isolation have been published, this report provides the first detailed description of the approaches, handling, and methodologies used for successful culture of this marine symbiosis. These techniques should permit a more widespread laboratory availability of these important marine symbioses. 

Abstract Advances in data‐logging technologies have provided a way to monitor the movement of individual animals at unprecedented spatial and temporal scales. When used in conjunction with social network analyses, these data can provide deep insight into the structure and dynamics of animal social systems. Emergence of these new technologies demands concomitant progress in workflows to translate data streams from automated systems to social networks, based on biologically relevant metrics.Here we outline key considerations for constructing social networks from automated telemetry data. We highlight the need for paying particular attention to the spatial arrangement of receiver stations with respect to the ecology of study system and developing appropriate criteria for quantifying associations.We provide a case study for constructing social networks from automated telemetry data collected over 1 month during a study of acorn woodpeckersMelanerpes formicivorus, a cooperatively breeding bird. The data consisted of detections of known birds near receiver stations placed within core areas of group territories. We use this system to demonstrate how to build social networks to investigate biological questions about patterns of associations between group members and territory visitors across the landscape. 

Experimental data about gene functions curated from the primary literature have enormous value for research scientists in understanding biology. Using the Gene Ontology (GO), manual curation by experts has provided an important resource for studying gene function, especially within model organisms. Unprecedented expansion of the scientific literature and validation of the predicted proteins have increased both data value and the challenges of keeping pace. Capturing literature-based functional annotations is limited by the ability of biocurators to handle the massive and rapidly growing scientific literature. Within the community-oriented wiki framework for GO annotation called the Gene Ontology Normal Usage Tracking System (GONUTS), we describe an approach to expand biocuration through crowdsourcing with undergraduates. This multiplies the number of high-quality annotations in international databases, enriches our coverage of the literature on normal gene function, and pushes the field in new directions. From an intercollegiate competition judged by experienced biocurators, Community Assessment of Community Annotation with Ontologies (CACAO), we have contributed nearly 5,000 literature-based annotations. Many of those annotations are to organisms not currently well-represented within GO. Over a 10-year history, our community contributors have spurred changes to the ontology not traditionally covered by professional biocurators. The CACAO principle of relying on community members to participate in and shape the future of biocuration in GO is a powerful and scalable model used to promote the scientific enterprise. It also provides undergraduate students with a unique and enriching introduction to critical reading of primary literature and acquisition of marketable skills.