Textbooks shape teaching and learning in introductory biology and highlight scientists as potential role models who are responsible for significant discoveries. We explore a potential demographic mismatch between the scientists featured in textbooks and the students who use textbooks to learn core concepts in biology. We conducted a demographic analysis by extracting hundreds of human names from common biology textbooks and assessing the binary gender and race of featured scientists. We found that the most common scientists featured in textbooks are white men. However, women and scientists of colour are increasingly represented in contemporary scientific discoveries. In fact, the proportion of women highlighted in textbooks has increased in lockstep with the proportion of women in the field, indicating that textbooks are matching a changing demographic landscape. Despite these gains, the scientists portrayed in textbooks are not representative of their target audience—the student population. Overall, very few scientists of colour were highlighted, and projections suggest it could take multiple centuries at current rates before we reach inclusive representation. We call upon textbook publishers to expand upon the scientists they highlight to reflect the diverse population of learners in biology.

Whether an ecological community is controlled from above or below remains a popular framework that continues generating interesting research questions and takes on especially important meaning in agroecosystems. We describe the regulation from above of three coffee herbivores, a leaf herbivore (the green coffee scale, Coccus viridis), a seed predator (the coffee berry borer, Hypothenemus hampei), and a plant pathogen (the coffee rust disease, caused by Hemelia vastatrix) by various natural enemies, emphasizing the remarkable complexity involved. We emphasize the intersection of this classical question of ecology with the burgeoning field of complex systems, including references to chaos, critical transitions, hysteresis, basin or boundary collision, and spatial self-organization, all aimed at the applied question of pest control in the coffee agroecosystem.

Due to the difficulty of tracking microbial dispersal, it is rarely possible to disentangle the relative importance of dispersal and species sorting for microbial community assembly. Here, we leverage a detailed multilevel network to examine drivers of bacterial community assembly within flowers. We observed flower visitors to 20 focal plant species in a coflowering community in the Sierra Nevada, revealing 289 species of arthropods. We also analyzed bacterial communities on flowers of each species. We found that plant species with similar visitor communities tend to have similar bacterial communities, and visitor identity to be more important than plant relatedness in structuring floral bacterial communities. However, plant species that were hubs of arthropod visitation were not necessarily hubs of floral bacteria, suggesting an important role for species sorting. Across plant species, the composition of flower-visiting Diptera (flies), bees and non-bee Hymenoptera best predicted bacterial species composition on flowers. Taken together, our analyses suggest dispersal is important in determining similarity in microbial communities across plant species, but not as important in determining the overall macrostructure (nestedness, modularity) and microstructure (connectedness based on shared interactors) of the floral bacterial network. A multilevel network approach thus allows us to address features of community assembly that cannot be considered when viewing networks as separate entities.

Metacommunity structure is strongly influenced by dispersal between habitat patches. Dispersal mode (e.g., active or passively via vector, wind, or water) is recognized to influence metacommunity dynamics, but it is not well understood how within-mode heterogeneity impacts dispersal and community assembly, particularly for microbial communities. Microbes often rely on flower visitors for dispersal among short-lived floral nectar habitats, but it is unclear whether flower visitor guilds (e.g., legitimate visitors vs. larcenists) differentially influence nectar microbial diversity and community structure. We surveyed the community of legitimate nectar foragers and nectar robbers, which damage flowers to obtain floral rewards, of Aquilegia formosa. Then, we evaluated how manipulating access by legitimate nectar foragers, primary nectar robbers, and/or secondary nectar robbers influenced the diversity, species composition, and beta diversity of nectar bacteria within individual flowers. A taxonomically diverse insect community visited A. formosa, and visitors differentially influenced nectar bacterial community structure at within-flower (local) and among-flower (regional) scales. When legitimate nectar foragers were allowed to access A. formosa, we observed an increase in bacterial diversity and changes in bacterial species composition such that common nectar bacteria had higher relative abundances. In contrast, effects of natural and simulated robbing had little effect on bacterial alpha diversity, but simulated robbing decreased the relative abundance of common nectar bacteria, and natural nectar robbing events reduced beta diversity of nectar bacteria. This work highlights the importance of visitor identity on microbial diversity and species composition in flowers, and, more broadly, suggests that vectors can differentially influence metacommunity structure.