This mixed-methods study reports the results of a survey completed by a sample of Puerto Rican social and natural scientists (STEM-S) regarding their perceptions of the intersectionalities of racism, colorism, colonialism, and the culture of science. Most participants ranked themselves as light-skinned and were familiar with the racist stereotypes presented in the survey, with female participants reporting hearing racial stereotypes significantly more frequently than males. Dark-skinned Latinx scientists were more likely to experience discriminatory practices in general, in K-12 schools, and at meetings with colleagues or peers. The higher the professional level, the fewer the interactions with coworkers or peers who were darker-skinned. Power differences among lighter and darker-skinned scientists were attributed to systemic and covert racism, discrimination, and the influences of slavery and colonialism. Fostering anti-racist education in K-16 STEM courses, and more Black and Afro-descendant mentors and role models were suggested as ways to challenge racial inequities in STEM-S fields.