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Phenology is an ecologically critical attribute that is commonly coordinated with other plant traits. Phenological shifts may be the result of evolutionary adjustments to persistently new conditions, or they may be transitory, varying with annual fluxes in abiotic conditions. In summer-dry, fire-prone Mediterranean-type climates, for example, many plant lineages have historically migrated from forests to more arid shrublands resulting in adaptive trait changes. These shifts in habitat abiotic conditions and biotic interactions influence morphology of flowers and fruits and interact with phenological timing. The Arbutoideae (Ericaceae) is one lineage that illustrates such modifications, with fruit characters evolving among genera from fleshy to dry fruit, thin to stony endocarps, and bird to rodent dispersal, among other changes. We scored herbarium collections and used ancestral trait analyses to determine phenological shifts among the five Arbutoid genera found in semi-arid climates. Our objective was to determine if phenology shifts with the phylogenetic transition to different reproductive characters. Our results indicate that phenological shifts began with some traits, like the development of a stony endocarp or dry fruits, but not with all significant trait changes. We conclude that early phenological shifts correlating with some reproductive traits were permissive for the transition to other later character changes. Key words: Ericaceae, fire regime, obligate seeding, scatter-hoarding, seed predation. La phenologie est un attribut critique d'un point de vue ecologique qui est generalement coordonne avec d'autres traits des vegetaux. Les changements phenologiques peuvent etre le resultat d'ajustements evolutifs a de nouvelles conditions persistantes, ou transitoires, qui varient avec le flux annuel des conditions abiotiques. Dans les climats mediterraneens secs en ete et sujets aux incendies, par exemple, de nombreux lignages de vegetaux ont historiquement migre des forets vers des zones arbustives plus arides, entrainant des changements en matiere de traits adaptatifs. Ces changements dans les conditions abiotiques de l'habitat et les interactions biotiques influencent la morphologie des fleurs et des fruits et interagiront avec le calendrier phenologique. Les Arbutoideae (Ericaceae) constituent un lignage qui illustre de telles modifications, les caracteres des fruits evoluant parmi les genres, de fruits charnus a secs, d'endocarpes minces a pierreux, et de dispersion par les oiseaux a une dispersion par les rongeurs, entre autres changements. Les auteurs ont analyse des collections d'herbiers et utilise l'analyse de traits ancestraux pour caracteriser les changements phenologiques parmi les cinq genres d'Arbutoides trouves dans des climats semi-arides. Leur objectif consistait a determiner si la phenologie change avec la transition phylogenetique vers des caracteres reproducteurs differents. Leurs resultats indiquent que les changements phenologiques ont commence avec certains traits, comme le developpement d'un endocarpe pierreux ou de fruits secs, mais pas avec tous les changements de traits significatifs. Ils concluent que les changements phenologiques precoces en correlation avec certains caracteres reproducteurs etaient permissifs pour la transition vers d'autres changements de caracteres ulterieurs. [Traduit par la Redaction] Mots-cles : Ericaceae, regime des incendies, semis obligatoire, eparpillement, predation des graines., Introduction Phenological changes that occur in coordination with fruit types is an understudied dimension of fruit evolution compared with dispersal or other traits (Forrest and Miller-Rushing 2010). Most studies investigating [...]

Many efforts to improve science teaching in higher education focus on a few faculty members at an institution at a time, with limited published evidence on attempts to engage faculty across entire departments. We created a long-term, department-wide collaborative professional development program, Biology Faculty Explorations in Scientific Teaching (Biology FEST). Across 3 years of Biology FEST, 89% of the department's faculty completed a weeklong scientific teaching institute, and 83% of eligible instructors participated in additional semester-long follow-up programs. A semester after institute completion, the majority of Biology FEST alumni reported adding active learning to their courses. These instructor self-reports were corroborated by audio analysis of classroom noise and surveys of students in biology courses on the frequency of active-learning techniques used in classes taught by Biology FEST alumni and nonalumni. Three years after Biology FEST launched, faculty participants overwhelmingly reported that their teaching was positively affected. Unexpectedly, most respondents also believed that they had improved relationships with departmental colleagues and felt a greater sense of belonging to the department. Overall, our results indicate that biology department-wide collaborative efforts to develop scientific teaching skills can indeed attract large numbers of faculty, spark widespread change in teaching practices, and improve departmental relations.

Premise: Ceanothus (Rhamnaceae) is a large genus of shrubs that dominate California chaparral and are resilient to fires. Persistence is ensured by resprouting and/or seedling recruitment from dormant seed banks. Some species do both and others, the obligate seeders, are entirely dependent on seedling recruitment. The distribution of these two modes within the genus is poorly documented. Methods: We used all available publications that document species responses to fire and filled most gaps in the literature based on extensive field studies of more than 60 recent wildfires in California. Results: The genus is divided into two subgenera, Ceanothus and Cerastes. Ceanothus is widely considered to comprise mostly resprouting species and Cerastes to consist of only obligate seeders. The subgenus Ceanothus includes resprouting species throughout their range from the eastern United States and Midwest to western United States. Within the California Floristic Province (CFP), a few species are unique in producing massive lignotubers that develop from repeated fires; however, within the CFP, the majority of species in this subgenus do not resprout and are obligate seeders. Two have disjunct subspecies that are facultative seeders or obligate seeders. Conclusions: Previously, speciation in this genus was contended to have occurred in the late Miocene within the CFP. The syndrome of obligate seeding is most strongly represented in this region, and we hypothesize that evolution of this syndrome was a response to increased predictability of fire driven by the Mediterranean climate and the long interval between fires. [ABSTRACT FROM AUTHOR]

Many efforts to improve science teaching in higher education focus on a few faculty members at an institution at a time, with limited published evidence on attempts to engage faculty across entire departments. We created a long-term, department-wide collaborative professional development program, Biology Faculty Explorations in Scientific Teaching (Biology FEST). Across 3 years of Biology FEST, 89% of the department's faculty completed a weeklong scientific teaching institute, and 83% of eligible instructors participated in additional semester-long follow-up programs. A semester after institute completion, the majority of Biology FEST alumni reported adding active learning to their courses. These instructor self-reports were corroborated by audio analysis of classroom noise and surveys of students in biology courses on the frequency of active-learning techniques used in classes taught by Biology FEST alumni and nonalumni. Three years after Biology FEST launched, faculty participants overwhelmingly reported that their teaching was positively affected. Unexpectedly, most respondents also believed that they had improved relationships with departmental colleagues and felt a greater sense of belonging to the department. Overall, our results indicate that biology department-wide collaborative efforts to develop scientific teaching skills can indeed attract large numbers of faculty, spark widespread change in teaching practices, and improve departmental relations.

We investigated the hypothesis that maritime climatic factors associated with summer fog and low cloud stratus (summer marine layer) help explain the compositional diversity of chaparral in the coast range of central California. We randomly sampled chaparral species composition in 0.1-hectare plots along a coast-to-interior gradient. For each plot, climatic variables were estimated and soil samples were analyzed. We used Cluster Analysis and Principle Components Analysis to objectively categorize plots into climate zone groups. Climate variables, vegetation composition and various diversity measures were compared across climate zone groups using ANOVA and nonmetric multidimensional scaling. Differences in climatic variables that relate to summer moisture availability and winter freeze events explained the majority of variance in measured conditions and coincided with three chaparral assemblages: maritime (lowland coast where the summer marine layer was strongest), transition (upland coast with mild summer marine layer influence and greater winter precipitation), and interior sites that generally lacked late summer water availability from either source. Species turnover (β-diversity) was higher among maritime and transition sites than interior sites. Coastal chaparral differs from interior chaparral in having a higher obligate seeder to facultative seeder (resprouter) ratio and by being dominated by various Arctostaphylos species as opposed to the interior dominant, Adenostoma fasciculatum. The maritime climate influence along the California central coast is associated with patterns of woody plant composition and β-diversity among sites. Summer fog in coastal lowlands and higher winter precipitation in coastal uplands combine to lower late dry season water deficit in coastal chaparral and contribute to longer fire return intervals that are associated with obligate seeders and more local endemism. Soil nutrients are comparatively less important in explaining plant community composition, but heterogeneous azonal soils contribute to local endemism and promote isolated chaparral patches within the dominant forest vegetation along the coast.

We analyzed tidal wetland vegetation patterns in the San Francisco Bay–Delta estuary (Bay–Delta) and discuss their significance for future conservation. Our objective was to conduct a balanced, random sample of six historic “remnant” tidal wetlands along a salinity gradient that ranged from southern San Pablo Bay to the lower Delta. We also wanted to compare diversity among these sites at five different scales, ranging from small subplots to total species per site. We randomly established twenty 0.1-ha plots at each site, and sampled ten 7-m2 circular subplots (subplot scale) in each plot for species presence and cover. We calculated total species per plot (plot scale) and total species per site (site scale) based on these subplot data. We calculated importance values for each species found in subplots based on frequency of occurrence and proportion of total cover at each site. In addition, we recorded species found within the 0.1-ha plot but not sampled in subplots (plot_all scale), and calculated the total species for each site based on these plot_all data (site_all scale). Thus, richness at each site was evaluated at five different scales that ranged from 7 m2 to 20,000 m2. We conducted a one-way ANOVA that compared mean richness among three scales with continuous data: subplot, plot, and plot_all. At lower estuary (San Pablo Bay) sites, richness values at these three scales were significantly lower than upper estuary (Suisun–Delta) sites. In Suisun–Delta sites, significant differences in richness varied, depending on sampling scale. Rush Ranch, a brackish wetland, had the highest average number of species per plot, whereas Sand Mound Slough, a freshwater wetland, had the highest average number of species at the subplot scale and the most total species at the site_all scale. Sand Mound Slough also had the highest number of unique species (22) compared to the other sites. We found a strong negative correlation (r2 = 0.99) between total species number and salinity (the most in the Delta at the lowest salinity, and the least at China Camp with the greatest salinity). Our analysis suggests the following conservation recommendations: (1) restore habitat for freshwater plant species diversity in the Delta; (2) restore transitional brackish wetland habitat in salt marshes of the San Pablo Bay and San Francisco Bay; and (3) focus on control of pepperweed (Lepidium latifolium) in brackish marshes.

Climate change will affect tidal wetlands with higher rates of sea-level rise and higher concentrations of salt in brackish and freshwater tidal systems, in addition to causing increases in atmospheric CO2 concentration, warmer temperatures, and shifts in precipitation. In the San Francisco Bay–Delta, the areas most likely to be affected—brackish and freshwater tidal wetlands—are also the sites with the majority of endemic plant species and the greater biodiversity and productivity. Effects on the San Francisco Bay– Delta estuary are complex and difficult to predict, but a few things are clear. Biodiversity of the tidal wetland system in the San Francisco Bay–Delta region will decline, with subsequent effects on ecosystem functioning and services. Altered plant production, physiological tolerances, and shifts in rates of mortality will modify wetland plant communities in ways not yet predictable. Lower ecosystem productivity from salinity increases will affect both primary and detrital-based food webs. Such changes will cascade via the food webs into invertebrate, bird, and pelagic systems. Tidal wetlands are especially sensitive to processes that climate change will alter. Several of these altered processes are exacerbated by water diversions from the Delta.

Early restoration efforts in San Francisco Bay focused primarily on establishing appropriate elevations for plant recruitment, based on plant distributions in natural wetlands. Sites were graded and planted, and tidal connections were re-established with the expectation that restored wetlands would quickly resemble natural ecosystems. Over time, restoration efforts have evolved, with the realization that natural development of restoration sites is preferable, including a dense channel network and the accumulation of soils of appropriate texture. Bay restoration efforts also have grown substantially in size and scope. Whereas projects of 50 hectares were considered large in the 1980s, now many projects are 100s of hectares. Larger projects are on the scale of 1000s of hectares, with the largest approximately 6000 hectares (the South Bay Salt Pond Restoration Project). This massive increase in scale has brought enormous restoration opportunities, but it also has increased the complexity of restoration projects and highlighted the necessity of large-scale public involvement. Awareness of non-native plants at restoration sites is just one example of factors that have increased restoration complexity. Potential impacts of climate change also have moved to the forefront of restoration design, as sea-level rise and potential shifts in salinity are critical factors for long-term restoration planning.