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The COVID-19 pandemic forced higher-education institutions to close campuses and pivot all face-to-face (F2F) instruction online. This transition to Crisis Distance Education (CDE) was unprecedented in scope and speed as it was implemented globally. We surveyed students in a large, introductory-level biology course to understand their opinions about the curricular changes we implemented, usefulness of resources we provided, and the extent to which they felt supported by course personnel during the transition to CDE. The survey included both Likert-scale and open-ended questions. In general, students had a positive opinion of the transition, particularly the option for synchronous or asynchronous participation in the remainder of the course. Students valued opportunities to communicate with course personnel, but gave mixed responses for whether more or less communication was desired. Students reported high use of graded resources, but low use of ungraded resources. Our results suggest that when faced with an unexpected transition to CDE, it is important to maintain regular, supportive, and synchronous communication, but also remain flexible for asynchronous participation. Grades and immediate point rewards were important factors motivating student use of e-resources and maintaining student engagement. These factors are important considerations when shifting instruction to CDE for a limited or extended time. [ABSTRACT FROM AUTHOR]

The article discusses the requirements for a case study to have a story not only to entertain but also to educate, citing the example of case studies available in the collection of the organization National Center for Case Study Teaching in Science. It also discusses the use of videos as a pedagogical tool.

The authors stress the importance of engaging in discussions to consider how to effectively educate life science students to have the data literacy they need to meet the challenges and changing face of science in the future.

Students often have limited understanding of the major innovations in plant evolution. We developed a card sorting activity based on tree thinking that is suitable for students with a wide range of abilities and experience. Through this activity, students learn how scientists organize taxa into biologically meaningful, natural groups that illustrate important events in terrestrial plant evolution. The activity corresponds to several NGSS standards and is suitable for use in classroom or laboratory settings and as a public educational outreach activity. The Botanical Phylo-Card Game addresses several components of Next Generation Science Standards (NGSS Lead States, 2013) such as Inheritance/Variation in Traits (3-LS3-1, HS-LS3-1, HS-LS4-2) and Natural Selection/Evolution (MS-LS4-2, HS-LS4-1). The game involves disciplinary core ideas about biodiversity, evolution, and common ancestry; crosscutting concepts regarding identification and interpretation of patterns; and scientific practices of constructing explanations and engaging in arguments from evidence that can guide individualized implementation and assessment of the activity by different instructors. [ABSTRACT FROM AUTHOR]

PREMISE OF THE STUDY: Bet-hedging strategies maximize long-term geometric fitness at the cost of reduced arithmetic fitness by offsetting different mortality risks. Heterocarpic systems accomplish bet-hedging through the production of two or more fruit types that vary in dormancy and dispersal ability. It is unknown whether heterocarpy also offsets predispersal mortality risks. To address this question, we investigated whether heterocarpy in Grindelia ciliata (Asteraceae) also offsets mortality risks posed by a seed predator Schinia mortua (Noctuidae) to increase plant fitness. METHODS: We conducted two manipulative experiments to quantify critical life history components of this plant-insect interaction. We measured predispersal achene mortality from herbivory, postdispersal achene mortality in the seed bank, and seedling emergence. These measurements were then used in deterministic models to evaluate evolutionary consequences of predispersal seed mortality in G. ciliata. KEY RESULTS: Dormant achene types were less vulnerable to herbivory but more susceptible to mortality in the seed bank due to delayed seed emergence. Nondormant achene types experienced high predispersal mortality but low seed bank mortality due to rapid germination. Our herbivore-dependent model improved fit between observed and expected proportions of dormant and nondormant G. ciliata achenes and showed that heterocarpy could evolve in the absence of postgermination mortality. CONCLUSIONS: Our study provides empirical support of how predispersal herbivory can be equally important to postdispersal seed mortality risks in the evolution and maintenance of a heterocarpic reproductive system and expands understanding of how bethedging theory can be used to understand this unique reproductive strategy. [ABSTRACT FROM AUTHOR]

Effective conservation requires an understanding of the genetic interactions among populations and individuals of a species, particularly those with fragmented, isolated distributions. Alnus maritima (seaside alder) is a rare tree species with an extremely fragmented distribution of highly isolated populations in the Delmarva Peninsula, Georgia, and Oklahoma. We conducted a mating system study to estimate the outcrossing rate, inbreeding coefficient, biparental inbreeding rate, and correlation of paternity in progeny from a Georgia and an Oklahoma population to investigate the effects of isolation on the A. maritima mating system. Data from nine microsatellite loci showed similarly high multilocus outcrossing rates in both populations (tm = 0.94). Individual tree outcrossing rates were also high (tm = 0.873-1.047). There was no significant biparental inbreeding in either population, but there was significantly higher correlated paternity in the Oklahoma population. Results showed the high outcrossing expected for a wind-pollinated, monoecious species that can promote the maintenance of genetic variation detected in A. maritima seed pools and standing populations. Likewise, pollen flow among Oklahoma populations may promote maintenance of regional genetic variation. However, despite the genetic diversity in the seed pool generated by A. maritima's highly outcrossed mating system, failure of new individuals to be recruited into populations from seed presents an obstacle that will need to be considered when developing conservation strategies for this rare species. [ABSTRACT FROM AUTHOR]

Comparisons of population genetic diversity between related rare and widespread species provide valuable insights to the con- sequences of rarity and are critical for conservation planning. Population genetic diversity of A. maritima, a rare species, was compared with its common, widespread congener A. serrulata to evaluate the impacts of small population size and high isolation on genetic diversity in A. maritima and to provide population genetic data to be used in conservation planning for A. maritima. Genetic data were also used to evaluate whether the disjunct distribution of A. maritima was due to range reduction or anthropogenic dispersal. Genetic diversity was lower in A. maritima (He = 0.217) than in A. serrulata (He = 0.268), and there is also higher inbreeding within A. maritima populations (f= 0.483) than A. serrulata populations (f= 0.269). The partitioning of genetic varia- tion was also higher among A. maritima populations (0 = 0.278), but not significantly different from that of A. serrulata (0 = 0. 197). Significant genetic differences among A. maritima populations support using local populations as seed sources for regional conservation efforts. The results also indicate that the highly disjunct distribution of A. maritima is due to natural range reduction in the past and not anthropogenic establishment of Oklahoma and Georgia populations. [ABSTRACT FROM AUTHOR]

We conducted a population genetic analysis of the heterocarpic species Heterotheca subaxillaris (Asteraceae, camphorweed) to determine whether there are mating system and, consequently, genotypic differences between ray and disc achene pools that correspond to ecological differences between achene morphs. No significant differences in levels of genetic diversity were detected between ray and disc achene pools of H. subaxillaris. A mixed mating system was measured overall (tm[sub TOTAL] = 0.648) and in separate ray (tm[sub RAY] = 0.736) and disc (tm[sub DISC] = 0.651) achene pools, and significant levels of inbreeding were detected in achene pools of most populations. We did not identify any relationships between the mating system of a floret and the dispersal traits of the achene morph it produces, nor did we identify a relationship between achene dispersal traits and the genotype of the seed contained within it. Our results indicate that frequent founder events and population bottlenecks promote high coancestry of individuals and significant levels of inbreeding within populations. Such high levels of inbreeding may impact the fitness of progeny from different achene morphs. However, differences in dispersal characteristics and seed provisioning between achene morphs may also shape progeny establishment success such that severity of inbreeding depression is reduced in H. subaxillaris and intermediate levels of self-fertilization can be evolutionarily stable. [ABSTRACT FROM AUTHOR]

Determines the ecological and genetic differences between ray and disc achene pools of the heteromorphic species Prionopsis ciliata. Heavier weight of ray achenes versus disc achenes; Detection of heterozygote deficiency in ray and disc achene seed pools; Self-fertilization of ray and disc florets.

Presents a comparative study floral development and male sterility in Ocotea tenera. Diagram of an Ocotea tenera flower in a longitudinal section; Methodology of study used; Developmental differences observed among gender classes; Arguments for gene, or genes, causing abortion of pollen grains in flowers of HF trees; Discussion on flower development and gender system evolution in Ocotea tenera.

Analyzes the structural specialization of female and hermaphroditic flowers of Lauraceae trees. Elements of the evolution of gynodioecy from hermaphroditism; Evaluation of the gender system evolution; Variations in the high fruiting and nonfruiting trees; Characteristics of hermaphroditic flowers; Efficiency of nutrient allocation.

Examines the progeny arrays of the Lauraceae plant, Ocotea tenera to estimate the reproductive outcrossing rate in the overall plant population. Differences in outcrossing percentages in hermaphroditic and female trees; Heterogeneity observed in single-locus outcrossing loci.

Phylogenetic trees are used throughout biology to represent evolutionary relationships and communicate ideas about evolutionary processes. Dedicated instruction in how to read and interpret phylogenetic trees (i.e., tree thinking) is necessary for students to be able to access this information. There are many cognitive barriers to mastering tree-thinking skills, and for some students, such as students who are blind or low-vision, there are physical barriers. We used a Universal Design for Learning (UDL) approach to increase the accessibility of the Great Clade Race, an effective activity for teaching tree-thinking skills. Here we provide an example of how applying a UDL approach reduced not only known barriers, but also barriers that were undetected until they were removed, providing benefits to all students. [ABSTRACT FROM AUTHOR]

Seed mortality due to low winter temperatures has been proposed as an explanation for the lack of seedling recruitment in natural populations of the rare riparian species Alnus maritima, but other factors such as the absence of essential root symbionts or canopy clearing disturbances could also limit establishment of new individuals. We investigated whether any of these factors could be identified as preventing recruitment into existing seaside alder populations. Stratification studies showed that not only can seeds withstand low temperatures, longer periods of cold stratification promote earlier seed germination and expand the temperature range for germination. Root microbiome studies unexpectedly found that seedlings inoculated with the native microbiome prior to planting had lower survival compared to uninoculated individuals, and uninoculated individuals declined in survivorship after natural inoculation in the field. Canopy disturbance by burning or clipping vegetation promoted neither seedling growth nor survival initially, with seedling survival lower in burned plots due to the release of an aggressively growing competitor. Our results show that physiological stress by microbial symbionts and competition with other species are likely primary limiting factors—more so than seed mortality from low temperatures—and should be the focus of future conservation efforts. [ABSTRACT FROM AUTHOR]

Phylogenies are a ubiquitous visual representation of core concepts in evolutionary biology and it is important that students develop an ability to read and correctly interpret these diagrams. However, as with any representation of complex disciplinary information, learning to correctly interpret phylogenies can be challenging, requiring that a diversity of educational strategies be deployed. Representational competence is the ability to develop and effectively use abstract representations. Accurately interpreting a phylogenetic tree as a presentation of evolutionary relationships requires that students develop general representational competence as well as knowledge of specific technical aspects of tree interpretation, such as knowing the graphical components of trees and what they represent. Here, we report on the development of a basic diagnostic tool of students' representational competence and technical skills with phylogenies, the Basic Evolutionary Tree‐Thinking Skills Instrument (BETTSI). This short, multiple‐choice instrument was designed to provide instructors with a quick diagnostic of students' ability to read and interpret phylogenies. It has been checked for reliability and validity and provides a convenient formative and summative assessment of students' understanding of evolutionary trees. [ABSTRACT FROM AUTHOR]

Alnus maritima and Alnus serrulata are riparian shrubs that occur in similar habitats in the southern and eastern United States. Alnus serrulata is abundant throughout this range, but A. maritima is rare, occurring only in small populations in Oklahoma and Georgia and on the Delmarva Peninsula. Alnus maritima is more resistant than A. serrulata to water and temperature stresses, but the degree to which insolation influences the restricted distribution of A. maritima is unknown. Our goals were to characterize the shade tolerance of A. maritima and A. serrulata and determine whether differences in shade tolerance could help explain the differing ecological success of the two species. Measurements in nature showed that leaves of A. serrulata have greater concentrations of chlorophyll than do leaves of A. maritima, and a greater percentage of A. serrulata inhabit shaded sites. Two experiments evaluating the resistance of seedlings to light-deficit stress revealed that A. maritima had a greater photosynthetic capacity and grew more quickly than A. serrulata in full sunlight. In shade, survival of seedlings was lower and reductions in photosynthesis and growth were greater for A. maritima than for A. serrulata. We conclude that A. serrulata is tolerant and A. maritima is intolerant of shade. Moreover, we conclude that shade intolerance strongly restricts the potential niches of A. maritima within the region where the shade-tolerant A. serrulata is comparatively abundant. [ABSTRACT FROM AUTHOR]