Faculty and peer interactions play a key role in shaping graduate student socialization. Yet, within the literature on graduate student socialization, researchers have primarily focused on understanding the nature and impact of faculty atone, and much less is known about how peer interactions also contribute to graduate student outcomes. Using a national sample of first-year biology doctoral students, this study reveals distinct categories that classify patterns of faculty and peer interaction. Further, we document inequities such that certain groups (e.g., underrepresented minority students) report constrained types of interactions with faculty and peers. Finally, we connect faculty and peer interaction patterns to student outcomes. Our findings reveal that, while the classification of faculty and peer interactions predicted affective and experiential outcomes (e.g., sense of belonging, satisfaction with academic development), it was not a consistent predictor of more central outcomes of the doctoral socialization process (e.g., research skills, commitment to degree). These and other findings are discussed, focusing on implications for future research, theory, and practice related to graduate training.

Purpose: The purpose of this study is to explore the experience of selecting and engaging in biological sciences laboratory rotations from the perspective of doctoral students. Design/methodology/approach: Within the socialization framework, this study uses a qualitative approach whereby 42 biological sciences students enrolled at highly selective US universities were interviewed in the first and second year of doctoral training about laboratory rotation experiences. Findings: The study revealed how doctoral students used formal and informal information networks, explored research topics, struggled with funding concerns and learned about the social aspect of the laboratories in which they rotated. Originality/value: While rotations are considered a signature pedagogy in the laboratory sciences, students’ experiences within them are understudied. This study offers new knowledge about what doctoral students experience while rotating that can be used to inform and improve rotation processes for both students and universities. © 2019, Emerald Publishing Limited.

The doctoral advisor-typically the principal investigator (PI)-is often characterized as a singular or primary mentor who guides students using a cognitive apprenticeship model. Alternatively, the cascading mentorship model describes the members of laboratories or research groups receiving mentorship from more senior laboratory members and providing it to more junior members (i.e., Pls mentor postdocs, postdocs mentor senior graduate students, senior students mentor junior students, etc.). Here we show that Pis' laboratory and mentoring activities do not significantly predict students' skill development trajectories, but the engagement of postdocs and senior graduate students in laboratory interactions do. We found that the cascading mentorship model accounts best for doctoral student skill development in a longitudinal study of 336 PhD students in the United States. Specifically, when postdocs and senior doctoral students actively participate in laboratory discussions, junior PhD students are over 4 times as likely to have positive skill development trajectories. Thus, postdocs disproportionately enhance the doctoral training enterprise, despite typically having no formal mentorship role. These findings also illustrate both the importance and the feasibility of identifying evidence-based practices in graduate education.