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.

This study of 2111 undergraduates examined the impact of online science courses on their anxiety. More than 50% of students reported experiencing at least moderate anxiety in online science courses. Aspects of online learning that increase and decrease anxiety are identified, and actions that instructors can take to lessen anxiety in online science courses are offered.

Crustaceans are known for their ability to autotomize and regenerate their appendages. The appendages that are most often autotomized are their chela, often specialized as claws, which serve essential functions including foraging, fighting, mating, and predator defense. Crustaceans with autotomized or regenerated chelae may suffer decreases in their ability to perform these functions compared to individuals with intact or original claws. It is noteworthy that although regenerated claws can grow back to the expected size of an original claw, regenerated claws often differ from original claws in external morphology and internal musculature. Both male and female crayfishes wield a pair of enlarged claws. It surprisingly remains unknown how the regeneration of crayfish claws influences the claws’ ability to generate pinching forces, which has previously been shown to influence the outcome of territorial contests. We investigated the relationship between claw regeneration and claw strength among male and female virile crayfish, Faxonius virilis (Hagen 1870). We found that maximal pinching forces of regenerated claws were weaker than the maximal pinching forces of original claws in both sexes (36% and 40% weaker in males and females, respectively). Further, regenerated claws had proportionally less muscle mass compared to original claws of equivalent size. These results present evidence of how claw regeneration influences pinching strength in crayfishes and suggest that such regeneration may be the functional mechanism that produces dishonest (large but weak) claws in crayfishes, but behavioral observations are required to support this hypothesis.

Resumen AbstractIn September 2006, at Parque Nacional Cerros de Amotape, department of Tumbes, Peru, 39 individuals of bats belonging to 16 species were captured. Parasitological analysis determined that only two individuals of the species Phyllostomus hastatus (Phyllostomidae) and Noctilio leporinus (Noctilionidae) were parasitized. The cestodes were collected from the small intestine and identified as Atriotaenia hastati Vaucher, 1982 (Anoplocephalidae) and Vampirolepis sp. (Hymenolepididae). Atriotaenia hastati is a new record for Peru and Vampirolepis sp. is registered for the first time in Tumbes and a new host, Noctilio leporinus.

Many studies on persistence in undergraduate research experiences have been almost exclusively conducted at research-intensive (R1) institutions, and it is unclear whether such challenges are generalizable across institution types. A study previously conducted across public R1 institutions was extended to include other institution types to address this question.