For many students biochemistry is a demanding course because they are expected to apply previously learned foundational concepts to new biological contexts. These foundational concepts serve as a scaffold onto which to build threshold concepts such as the physical basis of interactions. Unfortunately, many students possess misconceptions or gaps in knowledge of these foundational concepts which hinder their understanding of new information. This paper describes the implementation of an iterative process to improve student foundational concept learning in an introductory biochemistry course. The process includes pre-assessment of foundational concept knowledge, introduction of interventions targeting low performing concepts and re-assessment of student learning gains. Diverse active learning strategies such as problembased worksheets, tactile learning activities, review activities and learning cycle activities were introduced to target concepts including hydrogen bonding, pH/pKa, bond energy and chemical equilibrium. While all active learning strategies resulted in improved posttest scores compared to pretest scores, no one strategy appears to be more beneficial than another. Survey results suggest students recognized the value of utilizing the various active learning strategies in the classroom to enhance critical thinking skills, engagement during class time, and collaboration skills. The process allows instructors the breadth and flexibility to introduce diverse active learning strategies tailored to their specific student needs in an effort to improve student foundational concept learning.

Few studies have attempted to determine how physical injury affects predators. One of the ways that physical injury can be expressed is by autotomy or the voluntary loss of a body part. Here, we examined whether the loss of specific legs affects the foraging success of the wolf spider Rabidosa santrita (predator) on another species, Pardosa valens (prey). We also wanted to identify whether the loss of legs in both the predator and prey would impact the outcome of a predation event. Both predator and prey were collected from a creek bed at Portal, AZ, in 2012. Predators were randomly assigned groups where all prey items were intact or all prey had one randomly chosen leg IV removed. Within these groups, predators were organized into a control, leg I autotomy, or leg IV autotomy treatment. All predators had their pre-and post-foraging running speed determined. Predators were introduced into chambers with five prey items and allowed to forage for 1 h. The leg position autotomized or the comparison of pre-and post-foraging trials had no effect on predator running speed. Additionally, there was no significant effect of either predator or prey leg treatment on the total proportion of prey items captured by the end of the foraging trials. Survival analyses indicated that intact prey items tended to have a higher survival rate when predators were missing a leg IV than when predators were intact. When both the predator and prey were missing legs, no significant difference in prey survival rates was detected. We suggest that for predators that inhabit complex, heterogeneous habitats and are classified as ambush predators, the loss of a limb may affect prey capture success, especially when the prey is intact, but that increased sample size is necessary to determine whether this trend is significant.

Geographical isolation can over time accumulate life-history variation which can eventually lead to speciation. We used five species of Vaejovis scorpions that have been isolated from one another since the Pleistocene glaciation to identify if biogeographical patterns have allowed for the accumulation of life-history variation among species. Gravid females were captured and brought back to the lab until giving birth. Once offspring had begun to disperse, measurements of female size, reproductive investment, offspring size, offspring number, and variation in offspring size were recorded. Differences in how each species allocated energy to these variables were analysed utilizing path analysis and structural equation modelling. Female and offspring size, litter size, and total litter mass differed among species, but relative energetic investment did not. Most significant differences among species were not present after removing the effect of female size, indicating that female size is a major source of life-history variation. Path analyses indicated that there was no size-number trade-off within any species and that each species allocates energy toward total litter mass differently. Additionally, as offspring size increased, the variation in offspring mass decreased. These results show that each species allocates the same relative amount of energy in different ways. The variation seen could be a response to environmental variability or uncertainty, a product of maternal effects, or caused by the sufficient accumulation of genetic differences due to geographical isolation.

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