Dehydrated snakes reduce postprandial thermophily.

Transient thermophily in ectothermic animals is a common response during substantial physiological events. For example, ectotherms often elevate body temperature after ingesting a meal. In particular, the increase in metabolism during the postprandial response of pythons - known as specific dynamic action - is supported by a concurrent increase in preferred temperature. The objective of this study was to determine whether hydration state influences digestion-related behavioral thermophily. Sixteen (8 male and 8 female) Children's pythons (Antaresia childreni) with surgically implanted temperature data loggers were housed individually and provided with a thermal gradient of 25-45°C. Body temperature was recorded hourly beginning 6 days prior to feeding and for 18 days post-feeding, thus covering pre-feeding, postprandial and post-absorptive stages. Each snake underwent this 24 day trial twice, once when hydrated and once when dehydrated. Our results revealed a significant interaction between temperature preference, digestive stage and hydration state. Under both hydrated and dehydrated conditions, snakes similarly increased their body temperature shortly after consuming a meal, but during the later days of the postprandial stage, snakes selected significantly lower (∼1.5°C) body temperature when they were dehydrated compared with when they were hydrated. Our results demonstrate a significant effect of hydration state on postprandial thermophily, but the impact of this dehydration-induced temperature reduction on digestive physiology (e.g. passage time, energy assimilation) is unknown and warrants further study.

An Exploration across Institution Types of Undergraduate Life Sciences Student Decisions to Stay in or Leave an Academic-Year Research Experience.

Undergraduate research is one of the most valuable activities an undergraduate can engage in because of its benefits, and studies have shown that longer experiences are more beneficial. However, prior research has illuminated that undergraduates encounter challenges that may cause them to exit research prematurely. These studies have been almost exclusively conducted at research-intensive (R1) institutions, and it is unclear whether such challenges are generalizable to other institution types. To address this, we extended a study previously conducted at public R1 institutions. In the current study, we analyze data from 1262 students across 25 public R1s, 12 private R1s, 30 master's-granting institutions, and 20 primarily undergraduate institutions (PUIs) to assess 1) to what extent institution type predicts students' decisions to persist in undergraduate research and 2) what factors affect students' decisions to either stay in or consider leaving their undergraduate research experiences (UREs) at different institution types. We found students at public R1s are more likely to leave their UREs compared with students at master's-granting institutions and PUIs. However, there are few differences in why students enrolled at different institution types consider leaving or choose to stay in their UREs. This work highlights the importance of studying undergraduate research across institutions.

Factors that predict life sciences student persistence in undergraduate research experiences.

Undergraduate research experiences (UREs) have the potential to benefit undergraduates and longer UREs have been shown to lead to greater benefits for students. However, no studies have examined what causes students to stay in or consider leaving their UREs. In this study, we examined what factors cause students to stay in their UREs, what factors cause students to consider leaving their UREs, and what factors cause students to leave their UREs. We sampled from 25 research-intensive (R1) public universities across the United States and surveyed 768 life sciences undergraduates who were currently participating in or had previously participated in a URE. Students answered closed-ended and open-ended questions about factors that they perceived influenced their persistence in UREs. We used logistic regression to explore to what extent student demographics predicted what factors influenced students to stay in or consider leaving their UREs. We applied open-coding methods to probe the student-reported reasons why students chose to stay in and leave their UREs. Fifty percent of survey respondents considered leaving their URE, and 53.1% of those students actually left their URE. Students who reported having a positive lab environment and students who indicated enjoying their everyday research tasks were more likely to not consider leaving their UREs. In contrast, students who reported a negative lab environment or that they were not gaining important knowledge or skills were more likely to leave their UREs. Further, we identified that gender, race/ethnicity, college generation status, and GPA predicted which factors influenced students' decisions to persist in their UREs. This research provides important insight into how research mentors can create UREs that undergraduates are willing and able to participate in for as long as possible.