Peter J. T. White

Clicking for grades? Really? Investigating the use of clickers for awarding grade-points in post-secondary education

Using classroom response systems (clickers) to accumulate grade-points has become a controversial practice as response systems have become more widely used in the last decade. Although some instructors opt to use clickers on a non-grades basis, it has become quite common to reward students for (a) correct answers, (b) participating in clicker questions regardless of whether their answer is correct or incorrect, and (c) a combination of participation and correctness. Here, we discuss the appropriateness of using clickers for accumulating grade-points in academia and address two of the most common concerns raised with such practices: technology failure and cheating. The paucity of literature on clicker technology failure suggests that it is more sensationalized than real. Cheating remains a real issue, but can be minimized by educating students about clicker-related cheating policies and by staying away from high-stakes clicker-based testing. Research and expert opinion leads us to believe that the appropriateness of using clickers for accumulating grades depends on how they are used. We recommend rewarding students for giving correct answers or for participating in high-value constructivist learning activities. Rewarding students with participation grade-points for incorrect answers to trivia-style or simple-factual questions should be avoided because it primarily serves to reward students for their attendance in class.

The relationship between native and non-native species differs among taxa in Canadian national parks

ABSTRACT Invasive species are a growing international conservation concern. In Canada, the federal agency responsible for national parks, Parks Canada, has recently identified non-native species as important threats to the integrity and richness of Canadian national parks. To test for potential effects of non-native species on native richness, we examined the relationship between native and non-native/invasive species for 3 taxa – plants, mammals, and birds – in 42 Canadian national parks. We found positive relationships between native and non-native/invasive species richness for plants and birds and a negative relationship between native and non-native/invasive mammal species richness. Consistent with most large-scale studies, our results suggest that for birds and plants, regions that are good for native species are also good for non-native species. However, we provide one of the few examples of a negative relationship between native and non-native/invasive species. In mammals we show that there are more non-natives present in species-poor communities. This may indicate that non-native mammal species are having a negative impact on native species, that non-native mammal species are more able to invade richness-poor communities, or that a third factor such as fire, habitat degradation, or climate change has a negative effect on native species while having a positive effect on non-native species. In any case, it is evident that the pattern present between native and non-native mammals differs from those in plants and birds and could be representative of a negative effect associated with non-native introductions.

The Technical and Performance Characteristics of a Low-Cost, Simply Constructed, Black Light Moth Trap

The universal mercury vapor black light trap is an effective device used for collecting moth specimens in a wide variety of habitats; yet, they can present challenges for researchers. The mercury vapor trap is often powered by a heavy automotive battery making it difficult to conduct extensive surveys in remote regions. The mercury vapor trap also carries a considerable financial cost per trap unit, making trapping challenging with low research budgets. Here, we describe the development and trapping properties of a lighter, simply constructed, and less expensive trap. The LED funnel trap consists of a funnel, soda bottles with plastic vanes, and is powered by rechargeable 9-V batteries. Two strips of low-wavelength LEDs are used as attractants. We tested the trapping parameters of this trap design compared to a standard mercury vapor trap over 10 trap nights in a suburban woodlot in the summer of 2015. The mercury vapor trap caught significantly more moth individuals than the LED trap (average of 78 vs 40 moths per trap night; P < 0.05), and significantly more species than the LED trap (23 vs 15 per trap night; P < 0.05); the mercury vapor trap caught a total of 104 macromoth species over the duration of the study, compared to a total of 87 by the LED trap. Despite the lower yields, the low cost of the LED trap (<

Human-disturbance and caterpillars in managed forest fragments

30 ea.) makes it superior to the mercury vapor trap in cost-acquisition per moth species and per moth individual trapped. The LED trap may be a viable alternative to the standard mercury vapor trap, facilitating insect trapping in more diverse settings.

Community Patterns in Urban Moth Assemblages

The impact of forest-edge habitat on Lepidoptera assemblages has been well-studied, but the impact of trailside habitat has rarely been considered. We surveyed caterpillar populations in relation to recreational trails at 72 quadrats in four forest fragments in southeastern, Quebec, Canada. We found a consistent negative relationship between trails in the forest and both the abundance and species diversity of caterpillars within and among forest fragments. Conversely, caterpillar presence was not related to the presence of favorable host trees at a given quadrat. We suggest that the negative effect of trails may be due to increased predation pressure in trailside habitat and to conditions that make trailside habitat less preferable for oviposition. These results underscore the importance of managing trails to limit the amount of intra-forest disturbance experienced in important forest fragment remnants.

Testing two methods that relate herbivorous insects to host plants

ABSTRACT. In order to gain a better understanding of the effects of urbanization on insect biodiversity we compared moth assemblages between residential yards and urban woodlots in East Lansing, Michigan. We surveyed 36 sites over six trapping nights, for a total of 24 hours of nighttime light-trapping at each site. We captured over 2700 macromoth individuals and over 4000 micromoth individuals; more than 97% of macromoth individuals were identified to species. We analyzed differences in life history traits such as body size and feeding guild between residential moths and urban woodlot moths. Urban woodlots had a higher overall abundance of moths and higher species richness than residential yards. Residential yards were found to have a high proportion of “tourist species.” Urban woodlot moth species were significantly larger than residential moth species, leading us to hypothesize that larger moths may be more prone to predation in open habitats. The woodlot moth assemblage was also characterized by a higher percentage of tree generalist species; the residential moth assemblage had a higher percentage of grass/herb generalist species.

An Aerial Approach to Investigating the Relationship between Macromoths and Artificial Nighttime Lights Across an Urban Landscape

Abstract Insect herbivores are integral to terrestrial ecosystems. They provide essential food for higher trophic levels and aid in nutrient cycling. In general, research tends to relate individual insect herbivore species to host plant identity, where a species will show preference for one host over another. In contrast, insect herbivore assemblages are often related to host plant richness where an area with a higher richness of hosts will also have a higher richness of herbivores. In this study, the ability of these two approaches (host plant identity/abundance vs. host plant richness) to describe the diversity, richness, and abundance of an herbivorous Lepidoptera assemblage in temperate forest fragments in southern Canada is tested. Analyses indicated that caterpillar diversity, richness, and abundance were better described by quadrat-scale host plant identity and abundance than by host plant richness. Most host plant-herbivore studies to date have only considered investigating host plant preferences at a species level; the type of assemblage level preference shown in this study has been rarely considered. In addition, host plant replacement simulations indicate that increasing the abundance of preferred host plants could increase Lepidoptera richness and abundance by as much as 30% and 40% respectively in disturbed remnant forest fragments. This differs from traditional thinking that suggests higher levels of insect richness can be best obtained by maximizing plant richness. Host plant species that are highly preferred by the forest-dwelling caterpillar assemblage should be given special management and conservation considerations to maximize biodiversity in forest communities.

Molecular Sculpting: Active Learning of Subcellular Systems & Processes

Abstract Urbanization represents a dramatic type of habitat change. Not only does it remove natural habitat for ecological communities, it also increases artificial nighttime light levels that can have negative impacts on night-flying species, such as moths. Feeding, mating and oviposition behaviors of moths can be affected by artificial nighttime lights, and they become more exposed to predators such as bats. In this study, an aerial approach was used to measure the prevalence of artificial nighttime light across an urban landscape (East Lansing, Michigan, USA). These light levels were related to macromoth species richness and abundance at 32 urban trapping sites. Both moth species richness and abundance were positively related to vegetation cover across the landscape, but there was no consistent, discernible impact of artificial nighttime light on either variable. This may be due to the lower attractiveness of high-pressure sodium lights that are used across this particular urban landscape, or to a negative association between the prevalence of landscape light levels and the amount of landscape vegetation. There is also a possibility that macromoths in urban areas have adapted to be less sensitive to light. This study is one of the first to use an aerial approach to measuring urban nighttime lights and departs from the most commonly held theory that increased light prevalence is associated with a depauperate moth assemblage.

A Cross-Course Investigation of Integrative Cases for Evolution Education.

Abstract Students often struggle to understand the complex molecular systems and processes presented in introductory biology courses. These include the Calvin cycle, the Krebs cycle, transcription and translation, and DNA replication, among others. Traditionally, these systems and processes are taught using textbook readings and PowerPoint slides as lecture aids; video animations have also become popular in recent years. Students tend to be passive observers in many of these methods of instruction, relying heavily on “memorization” learning techniques. To address this, I developed an active-learning intervention called “molecular sculpting” in which students construct two-dimensional or three-dimensional versions of an assigned molecular system or process, complete with representations of proteins, chromosomes, electrons, protons, and other molecules (depending on the system). The value of this learning activity was measured in five class sessions in an introductory biology course during the 2014–2015 academic year. Pre- and postclass written assignments showed that students were often able to describe course concepts more completely after sessions in which sculpting was used, compared with sessions without sculpting. Molecular sculpting is a unique, hands-on activity that appears to have significant learning gains associated with it; it can be adapted for use in a variety of K—14 biology courses.

Human impacts on environment-diversity relationships: evidence for biotic homogenization from butterfly species richness patterns

Evolution is a cornerstone theory in biology, yet many undergraduate students have difficulty understanding it. One reason for this is that evolution is often taught in a macro-scale context without explicit links to micro-scale processes. To address this, we developed a series of integrative evolution cases that present the evolution of various traits from their origin in genetic mutation, to the synthesis of modified proteins, to how these proteins produce novel phenotypes, to the related macro-scale impacts that the novel phenotypes have on populations in ecological communities. We postulated that students would develop a fuller understanding of evolution when learning biology in a context where these integrative evolution cases are used. We used a previously developed assessment tool, the ATEEK (Assessment Tool for Evaluating Evolution Knowledge), within a pre-course/post-course assessment framework. Students who learned biology in courses using the integrative cases performed significantly better on the evolution assessment than did students in courses that did not use the cases. We also found that student understanding of evolution increased with increased exposure to the integrative evolution cases. These findings support the general hypothesis that students acquire a more complete understanding of evolution when they learn about its genetic and molecular mechanisms along with macro-scale explanations.