With the advent of wireless technology, new tools are available that are intended to enhance students' learning and attitudes. To assess the effectiveness of wireless student response systems in the biology curriculum at New Mexico State University, a combined study of student attitudes and performance was undertaken. A survey of students in six biology courses showed that strong majorities of students had favorable overall impressions of the use of student response systems and also thought that the technology improved their interest in the course, attendance, and understanding of course content. Students in lower-division courses had more strongly positive overall impressions than did students in upper-division courses. To assess the effects of the response systems on student learning, the number of in-class questions was varied within each course throughout the semester. Students' performance was compared on exam questions derived from lectures with low, medium, or high numbers of in-class questions. Increased use of the response systems in lecture had a positive influence on students' performance on exam questions across all six biology courses. Students not only have favorable opinions about the use of student response systems, increased use of these systems increases student learning.

The white oaks Quercus gambelii and Q. grisea overlap in distribution in New Mexico and Arizona. Within the region of overlap, there are numerous instances of contact between the two taxa. In some areas of contact morphologically, intermediate trees are common, whereas in others, morphologically intermediate trees are rare or absent. We describe a set of RAPD markers that distinguish between the two species and use these markers to examine patterns of gene exchange in an area of contact in the San Mateo Mountains of New Mexico. The markers are highly coincident with morphology and confirm that hybridization between the two species takes place. Despite the occurrence of hybrids, both species remain distinct, even in areas of sympatry, and marker exchange appears to be limited.

Peer-facilitated workshops enhanced interactivity in our introductory biology course, which led to increased student engagement and learning. A majority of students preferred attending two lectures and a workshop each week over attending three weekly lectures. In the workshops, students worked in small cooperative groups as they solved challenging problems, evaluated case studies, and participated in activities designed to improve their general learning skills. Students in the workshop version of the course scored higher on exam questions recycled from preworkshop semesters. Grades were higher over three workshop semesters in comparison with the seven preworkshop semesters. Although males and females benefited from workshops, there was a larger improvement of grades and increased retention by female students; although underrepresented minority (URM) and non-URM students benefited from workshops, there was a larger improvement of grades by URM students. As well as improving student performance and retention, the addition of interactive workshops also improved the quality of student learning: Student scores on exam questions that required higher-level thinking increased from preworkshop to workshop semesters.

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In the field, population density of a shoot—galling sawfly Euura lasiolepis was on eighth as great and mortality was five times as great in dry habitats as in wet habitats. The effect of host water stress on Euura populations was experimentally tested by initiating Euura populations on potted Salix lasiolepis willow plants given various amounts of water. As in wild populations Euura mortality was much higher (2.5 times) on waterstressed Salix. The life table analyses of experimental Euura cohorts began with the potential number of eggs in the adult females of the preceding generation. This enabled us to describe the effects of female reproductive responses to host quality on Euura densities. These responses, failure to initiate a gall or to release an egg during gall initiation, resulted in a 27.5% reduction of the Euura cohort on hosts given a high—water treatment and an 85.1% reduction on low—water hosts. Excluding behavioral limits on the potential number of eggs laid, first—instar larval death was the largest and most variable Euura mortality factor of the experimental populations. Host water treatment accounted for 51.9% of the variance in first—instar larval mortality (P ° .001), with 13.6% of the first instars dying on hosts given high—water treatments and 54.5% dying on the low—water hosts. The threefold decrease in gall initiation and egg release on water—stressed hosts has probably been selected for by the fourfold increase in first—star larval mortality on these water—stressed hosts. From an evolutionary perspective the reproductive behaviors have amplified the effects of the first—instar mortality. From an ecological perspective the reproductive responses of the adult females were the critical factors regulating Euurra densities. Understanding the effect of variation in host quality on herbivore survivorship and behavior is essential to understanding the densities of local herbivore populations and should be routinely incorporated into life table analyses.