In 2013, a vaccine policy inadvertently launched a massive natural experiment that would offer new clues about the roots of ...

Dive into PNAS Front Matter for editorials, interviews, science news, and commentary that offer expert perspective on today’s most important research findings.

Pseudo-colored amoebae explore the openings of two-micrometer channels. Lysergic acid diethylamide (LSD) is a well-known psychedelic drug. Although it holds promise as a potential treatment for some ...

PNAS publishes peer-reviewed research in psychological and cognitive sciences, including studies on decision-making, language processing, emotional regulation, cognitive development, and more. These ...

Diamant and Yeh surveyed urban (University of California, Los Angeles campus) and non-urban populations of dark-eyed juncos (Junco hyemalis) between 2018 and 2025 (1). Second-year urban birds had ...