Tackling the difficulties in learning evolution: effects of adaptive self-explanation prompts

Teaching and learning evolution is challenging. Biology education research shows that the underlying evolutionary concepts are poorly understood among students. This prevents a meaningful understanding of the central biological concepts. The instructional format of self-explanation prompts seems to be promising to respond to these difficulties. However, previous research has shown that the interaction between prior knowledge and prompts is an important factor in enhancing effective self-explanations. Nevertheless, there are hardly any studies which focus on the majority of learners in the classrooms, ie students with average prior knowledge. The aim of this study was to analyse the requirements of adaptive self-explanation prompts specifically for these learners. This should enable students at all knowledge levels to be effectively fostered in self-explaining, while they are learning evolution. We investigated the effects of three kinds of prompts for fostering self-explanations: learners with average prior knowledge were prompted with low or/and high-knowledge prompts. Our analysis of 22 verbal protocols by middle-school German students shows that the prompts evoked the intended self-explanations. The most positive impact with regard to self-explanation quality was created by the prompting condition which combines low-knowledge and high-knowledge self-explanation characteristics.     

EvoSketch: Simple simulations for learning random and probabilistic processes in evolution,and effects of instructional support on learners’ conceptual knowledge

Background

Students’ knowledge of scientific principles of evolution is often inadequate, despite its recognized importance for understanding biology. Moreover, difficulties associated with underlying abstract concepts such as randomness and probability can hinder successful learning of evolutionary concepts. Studies show that visualizations, particularly simulations together with appropriate instructional support, facilitate the learning of abstract concepts. Therefore, we have developed interactive, web-based simulation software called EvoSketch in efforts to help learners grasp the nature and importance of random and probabilistic processes in evolutionary contexts. We applied EvoSketch in an intervention study comparing four self-directed study conditions: learning with EvoSketch (1) alone, (2) combined with interpretative support, (3) combined with reflective support, and (4) using texts about randomness and probability instead of EvoSketch. All conditions received no support from any instructors. Knowledge about evolution as well as randomness and probability in the context of evolution, time-on-task, and perceived cognitive load were measured. A sample of 269 German secondary school students (M_age?=?15.6 years, SD?=?0.6 years) participated in the study.

Results

Learners using EvoSketch without additional support obtained higher follow-up test scores regarding their knowledge of randomness and probability than those using the text-based approach. However, use of the simulations together with given instructional support (interpretative or reflective) did not increase students’ performance, relative to the text-based approach. In addition, no significant between-intervention differences were found concerning the knowledge of evolution, while significant differences between the groups were detected concerning students’ perceived cognitive load and time-on-task.

Conclusions

From our findings, we conclude that EvoSketch seems to have a very small positive effect on students’ understanding of randomness and probability. Contrary to our expectations, additional self-directed instructional support did not improve students’ understanding, probably because it was not necessary to understand EvoSketch simulations. When using EvoSketch in the classroom, we recommend increasing the intervention timeframe to several sessions and a variety of evolutionary examples for which EvoSketch serves as an underlying framework.

     

All Aboard! The Polar Express Is Traveling to Science—Understanding the States of Matter while Differentiating Instruction for Young Learners

This standards-based science lesson introduces young learners to scientific inquiry and critical thinking by using activities to demonstrate three phases of matter (solid, liquid, and gas). By learning about the states of matter through a 5E instructional approach, students are encouraged to observe changes in the states of matter and to discuss their understanding in both small and large group forums. Student participants will be involved in hands-on activities along with small and large group discourse while actively learning about the states of matter and enjoying a hot chocolate demonstration with sampling. Developmentally appropriate instructional approaches are emphasized throughout this lesson.     

Revision bingo

Bingo can be a versatile and engaging tool for spicing up end-of-module revision and other contexts in which course content is being reviewed. Instead of numbers being called out, students are given a verbal clue that fits with one of the answers on their playing grid. Get five correct answers in any straight line (including either of the major diagonals) and they win the game. The interactive and light-hearted medium of a bingo game can provide motivation for study and enhance learning by the students. Protein revision bingo is included as an example.     

Myeloperoxidase impairs the contractile function in isolated human cardiomyocytes

We set out to characterize the mechanical effects of myeloperoxidase (MPO) in isolated left-ventricular human cardiomyocytes. Oxidative myofilament protein modifications (sulfhydryl (SH)-group oxidation and carbonylation) induced by the peroxidase and chlorinating activities of MPO were additionally identified. The specificity of the MPO-evoked functional alterations was tested with an MPO inhibitor (MPO-I) and the antioxidant amino acid Met. The combined application of MPO and its substrate, hydrogen peroxide (H₂O₂), largely reduced the active force (F_active), increased the passive force (F_passive), and decreased the Ca²⁺ sensitivity of force production (pCa₅₀) in permeabilized cardiomyocytes. H₂O₂ alone had significantly smaller effects on F_active and F_passive and did not alter pCa₅₀. The MPO-I blocked both the peroxidase and the chlorinating activities, whereas Met selectively inhibited the chlorinating activity of MPO. All of the MPO-induced functional effects could be prevented by the MPO-I and Met. Both H₂O₂ alone and MPO + H₂O₂ reduced the SH content of actin and increased the carbonylation of actin and myosin-binding protein C to the same extent. Neither the SH oxidation nor the carbonylation of the giant sarcomeric protein titin was affected by these treatments. MPO activation induces a cardiomyocyte dysfunction by affecting Ca²⁺-regulated active and Ca²⁺-independent passive force production and myofilament Ca²⁺ sensitivity, independent of protein SH oxidation and carbonylation. The MPO-induced deleterious functional alterations can be prevented by the MPO-I and Met. Inhibition of MPO may be a promising therapeutic target to limit myocardial contractile dysfunction during inflammation.     

The Effects of Drought and Shade on the Performance,Morphology and Physiology of Ghanaian Tree Species

In tropical forests light and water availability are the most important factors for seedling growth and survival but an increasing frequency of drought may affect tree regeneration. One central question is whether drought and shade have interactive effects on seedling growth and survival. Here, we present results of a greenhouse experiment, in which seedlings of 10 Ghanaian tree species were exposed to combinations of strong seasonal drought (continuous watering versus withholding water for nine weeks) and shade (5% irradiance versus 20% irradiance). We evaluated the effects of drought and shade on seedling survival and growth and plasticity of 11 underlying traits related to biomass allocation, morphology and physiology. Seedling survival under dry conditions was higher in shade than in high light, thus providing support for the “facilitation hypothesis” that shade enhances plant performance through improved microclimatic conditions, and rejecting the trade-off hypothesis that drought should have stronger impact in shade because of reduced root investment. Shaded plants had low biomass fraction in roots, in line with the trade-off hypothesis, but they compensated for this with a higher specific root length (i.e., root length per unit root mass), resulting in a similar root length per plant mass and, hence, similar water uptake capacity as high-light plants. The majority (60%) of traits studied responded independently to drought and shade, indicating that within species shade- and drought tolerances are not in trade-off, but largely uncoupled. When individual species responses were analysed, then for most of the traits only one to three species showed significant interactive effects between drought and shade. The uncoupled response of most species to drought and shade should provide ample opportunity for niche differentiation and species coexistence under a range of water and light conditions. Overall our greenhouse results suggest that, in the absence of root competition shaded tropical forest tree seedlings may be able to survive prolonged drought.     

Model eliciting activities: another tool for the elementary teaching toolbox

Abstract

Maximizing classroom time to include meaningful content-based learning with fun engaging activities that simultaneously challenge and encourage students is a hallmark of a successful school day. This article shares one instructional approach that does a model eliciting activity (MEA). A MEA is a real-world, problem-based scenario framed around a fictitious client who writes a letter in which the client poses a problem for students to address. Students use the engineering design process to brainstorm, create, and test models, then compose written and oral responses to the client citing evidence to justify their solution. The content of the client letter is created by the classroom teacher and based on the Next Generation Science Standards, the teacher wishes to address. The depth of the content addressed is at the teacher’s discretion and may vary depending on sequence of lessons within the unit of study, developmental readiness of students, and standard(s) selected.     

Time-course of memory formation differs in honey bee lines selected for good and poor learning

Six lines of the honey bee Apis mellifera capensis were selected for good and poor learning, and compared with respect to the time-course of their memory after a single learning trial to an odour stimulus (geraniol). The good learners showed the well known bi-phasic time-course with a high rate of conditioned responses immediately after learning, followed by a reduction 1–3 min later and a consolidation into a long-term memory after an interval longer than 5 min. Poor learners differed significantly with respect to their consolidation period and the initial high response rate. The initial period (of less than 1 min) is controlled not only by the associative memory of the learning trial but also by a sensitizing effect of the sucrose stimulus which was used as an unconditioned stimulus. It is concluded that the lines selected for learning performance differ with respect to the establishment of a long-term memory trace. As in Drosophila learning mutants, differences between good and poor learners are also affected by non-associative processes involved in sensitization.     

Patterns of Change: Forces and Motion

Patterns of Change: Forces and Motion is an integrated science lesson that uses the 5E lesson cycle to tie together science with language arts, mathematics, literature, technology, engineering and social studies in an engaging format applicable for young learners. This lesson has been uniquely designed for the purpose of providing elementary teachers with ideas for using hands-on minds-on activities to foster inquiry and discussion, while engaging their students to use technology as a learning tool. This lesson has been used on the elementary level to teach students about the forces that have an effect on motion.     

Planning Continuing Medical Education Activities

A review of program development literature in adult education and continuing medical education (CME) indicates the pervasive influence of a single approach to designing instructional activities. An examination of the assumptions of this model indicates several weaknesses. An alternative model is proposed that recognizes the importance and impact of the planners'' interaction with representatives of the learner group, institutional colleagues and persons in outside agencies. Results of previous research, experience in planning, observations of the planning processes of others and discussions with expert continuing medical educators show that planning is a dynamic process of suggesting and selecting from many alternatives those instructional activities with the greatest potential for effecting the desired changes in learners. Through a series of deliberations, needs are specified, instructional activities are designed, goals and objectives are stated, and evaluation techniques are selected. CME planners direct the process and constantly focus on the immediate impact on the learners and ultimately on the learners'' practice behavior.     

Too much teaching, not enough learning: what is the solution?

The curriculum is packed with so much content that teachers resort to telling students what they know and students simply commit facts to memory. The packed curriculum leaves little time for students to acquire a deep understanding of the subject or to develop life-long skills such as critical thinking, problem solving, and communication. However, learning is not committing a set of facts to memory, but the ability to use resources to find, evaluate, and apply information. This paper addresses these concerns by discussing "how we learn" and reviewing the literature on what works to improve learning. It is clear that active processing of information, not passive reception of information, leads to learning. That is, students must construct their own understanding of concepts, relationships, and procedures. Teachers can encourage this process by carefully considering the type and organization of information as well as instructional strategies. Specifically, teachers should reduce the total amount of factual information students are expected to memorize, reduce our use of the passive lecture format, and devote much more effort to helping students become active, independent learners and problem solvers. Collaborative learning activities, interactive models, educational games, and establishing a culture of inquiry/scholarship are critical for achieving these goals.     

Interactive instruction of cellular physiology for remote learning.

The biomedical sciences are a rapidly changing discipline that have adapted to innovative technological advances. Despite these many advances, we face two major challenges: a) the number of experts in the field is vastly outnumbered by the number of students, many of whom are separated geographically or temporally and b) the teaching methods used to instruct students and learners have not changed. Today's students have adapted to technology--they use the web as a source of information and communicate via email and chat rooms. Teaching in the biomedical sciences should adopt these new information technologies (IT), but has thus far failed to capitalize on technological opportunity. Creating a "digital textbook" of the traditional learning material is not sufficient for dynamic processes such as cellular physiology. This paper describes innovative teaching techniques that incorporate familiar IT and high-quality interactive learning content with user-centric instruction design models. The Virtual Labs Project from Stanford University has created effective interactive online teaching modules in physiology (simPHYSIO) and delivered them over broadband networks to their undergraduate and medical students. Evaluation results of the modules are given as a measure of success of such innovative teaching method. This learning media strategically merges IT innovations with pedagogy to produce user-driven animations of processes and engaging interactive simulations.     

Olfactory associative behavioral differences in three honey bee Apis mellifera L. races under the arid zone ecosystem of central Saudi Arabia

Apis mellifera jemenitica is the indigenous race of honey bees in the Arabian Peninsula and is tolerant to local drought conditions. Experiments were undertaken to determine the differences in associative learning and memory of honey bee workers living in the arid zone of Saudi Arabia, utilizing the proboscis extension response (PER). These experiments were conducted on the indigenous race (A. m. jemenitica) along with two introduced European races (A. m. carnica and A. m. ligustica). The data revealed that A. m. jemenitica is amenable to PER conditioning and may be used in conditioning experiments within the olfactory behavioral paradigm. The results also demonstrated that the three races learn and retain information with different capacities relative to each other during the experimental time periods. Native Arabian bees (A. m. jemenitica) exhibited significantly lower PER percentage during second and third conditioning trials when compared to exotic races. Apis mellifera jemenitica also exhibited reduced memory retention at 2?h and 24?h when compared to A. m. carnica and A. m. ligustica. Therefore, the native Arabian bees were relatively slow learners with reduced memory retention compared to the other two races that showed similar learning and memory retention. Three or five conditioning trials and monthly weather conditions (October and December) had no significant effects on learning and memory in A. m. jemenitica. These results emphasized a novel line of research to explore the mechanism and differences in associative learning as well as other forms of learning throughout the year among bee races in the harsh arid conditions of Saudi Arabia. This is the first study in Saudi Arabia to demonstrate inter-race differences regarding olfactory associative learning between native Arabian bees and two introduced European honey bee races.     

A student-centred,problem-based curriculum: 5 years' experience.

In 1987, the University of Sherbrooke''s school of medicine implemented a student-centred, problem-based learning (PBL) curriculum. The experience of the first 5 years is reviewed; program goals, the schedule of learning activities, the instructional format and assessment of student learning are described. The new program is more demanding of teachers and requires better faculty training in pedagogy. No new financial resources have been available. The preclinical reform has led to revision of the clerkship, where sessions on clinical reasoning are now based on the PBL philosophy. Student reactions to the program are reported. The Sherbrooke experience has demonstrated that it is both possible and feasible to shift from a traditional to a problem-based curriculum.     

优化遗传学教学设计的实践与探讨

遗传学教学中采用优化教学设计：加强以学生为中心,促进学生对知识的意义建构;注重信息技术与课程整合,有效利用网络遗传信息资源,培养学生信息素养和自主学习能力;强化研究性实验操作,培养综合能力;重视教与学双边活动,营造融洽互动的教学环境。优化教学设计可充分调动和发挥学生的主体作用,实现知识和能力的转化,为21世纪培养优秀的生物教育工作者。     

Prestige-biased cultural learning: bystander's differential attention to potential models influences children's learning

Reasoning about the evolution of our species' capacity for cumulative cultural learning has led culture-gene coevolutionary (CGC) theorists to predict that humans should possess several learning biases which robustly enhance the fitness of cultural learners. Meanwhile, developmental psychologists have begun using experimental procedures to probe the learning biases that young children actually possess — a methodology ripe for testing CGC. Here we report the first direct tests in children of CGC's prediction of prestige bias, a tendency to learn from individuals to whom others have preferentially attended, learned or deferred. Our first study showed that the odds of 3- and 4-year-old children learning from an adult model to whom bystanders had previously preferentially attended for 10 seconds (the prestigious model) were over twice those of their learning from a model whom bystanders ignored. Moreover, this effect appears domain-sensitive: in Study 2 when bystanders preferentially observed a prestigious model using artifacts, she was learned from more often on subsequent artifact-use tasks (odds almost five times greater) but not on food-preference tasks, while the reverse was true of a model who received preferential bystander attention while expressing food preferences.     

Deep Learning for Population Genetic Inference

Given genomic variation data from multiple individuals, computing the likelihood of complex population genetic models is often infeasible. To circumvent this problem, we introduce a novel likelihood-free inference framework by applying deep learning, a powerful modern technique in machine learning. Deep learning makes use of multilayer neural networks to learn a feature-based function from the input (e.g., hundreds of correlated summary statistics of data) to the output (e.g., population genetic parameters of interest). We demonstrate that deep learning can be effectively employed for population genetic inference and learning informative features of data. As a concrete application, we focus on the challenging problem of jointly inferring natural selection and demography (in the form of a population size change history). Our method is able to separate the global nature of demography from the local nature of selection, without sequential steps for these two factors. Studying demography and selection jointly is motivated by Drosophila, where pervasive selection confounds demographic analysis. We apply our method to 197 African Drosophila melanogaster genomes from Zambia to infer both their overall demography, and regions of their genome under selection. We find many regions of the genome that have experienced hard sweeps, and fewer under selection on standing variation (soft sweep) or balancing selection. Interestingly, we find that soft sweeps and balancing selection occur more frequently closer to the centromere of each chromosome. In addition, our demographic inference suggests that previously estimated bottlenecks for African Drosophila melanogaster are too extreme.     

The thermal mismatch hypothesis explains host susceptibility to an emerging infectious disease

Parasites typically have broader thermal limits than hosts, so large performance gaps between pathogens and their cold‐ and warm‐adapted hosts should occur at relatively warm and cold temperatures, respectively. We tested this thermal mismatch hypothesis by quantifying the temperature‐dependent susceptibility of cold‐ and warm‐adapted amphibian species to the fungal pathogen Batrachochytrium dendrobatidis (Bd) using laboratory experiments and field prevalence estimates from 15 410 individuals in 598 populations. In both the laboratory and field, we found that the greatest susceptibility of cold‐ and warm‐adapted hosts occurred at relatively warm and cool temperatures, respectively, providing support for the thermal mismatch hypothesis. Our results suggest that as climate change shifts hosts away from their optimal temperatures, the probability of increased host susceptibility to infectious disease might increase, but the effect will depend on the host species and the direction of the climate shift. Our findings help explain the tremendous variation in species responses to Bd across climates and spatial, temporal and species‐level variation in disease outbreaks associated with extreme weather events that are becoming more common with climate change.     

Voluntary Modulation of Anterior Cingulate Response to Negative Feedback

Anterior cingulate and medial frontal cortex (dACC/mFC) response to negative feedback represents the actions of a generalized error-monitoring system critical for the management of goal-directed behavior. Magnitude of dACC/mFC response to negative feedback correlates with levels of post-feedback behavioral change, and with proficiency of operant learning processes. With this in mind, it follows that an ability to alter dACC/mFC response to negative feedback may lead to representative changes in operant learning proficiency. To this end, the present study investigated the extent to which healthy individuals would show modulation of their dACC/mFC response when instructed to try to either maximize or minimize their neural response to the presentation of contingent negative feedback. Participants performed multiple runs of a standard time-estimation task, during which they received feedback regarding their ability to accurately estimate a one-second duration. On Watch runs, participants were simply instructed to try to estimate as closely as possible the one second duration. On Increase and Decrease runs, participants performed the same task, but were instructed to “try to increase [decrease] their brain''s response every time they received negative feedback”. Results indicated that participants showed changes in dACC/mFC response under these differing instructional conditions: dACC/mFC activity following negative feedback was higher in the Increase condition, and dACC activity trended lower in the Decrease condition, compared to the Watch condition. Moreover, dACC activity correlated with post-feedback performance adjustments, and these adjustments were highest in the Increase condition. Potential implications for neuromodulation and facilitated learning are discussed.