Proceedings of the National Academy of Sciences (PNAS)

Vaccine data suggest immunity could mitigate dementia. What’s the biology behind these apparent effects?

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

AI cannot replace human participants in behavioral research

AI tools offer researchers real benefits, including literature reviews, data analysis, and even drafting articles. A more troubling use of this technology, however, is becoming widespread. Researchers ...
PNAS

In This Issue

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

Reply to Doyle: Emphasizing independent gene duplications and convergent molecular function

The duplication history of NFP (7) is thus inconsistent with a single origin of RNS (4). With no new data, Doyle has challenged our interpretation of molecular convergence of NFP by focusing on ...
PNAS

Correction for Chi et al., Urban tree canopy fragmentation and child mortality in low- and middle-income countries

The authors note that the affiliation for Simone Fatichi should appear as Department of Civil and Environmental Engineering, College of Design and Engineering, National University of Singapore, ...
PNAS

Behavioral similarity likely drives interbrain neural synchrony

Hyperscanning methods where brain imaging data are acquired from two or more people simultaneously are increasingly being used in the field of social neuroscience. However, the interpretation of these ...
PNAS

Unexplained rapid bill-size changes in an urban bird during the COVID-19 anthropause

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 ...
PNAS

Retraction for Wang et al., Chemical ecology and convergent evolution of natural hallucinogens: From ecological defense to conserved neural targets

The editors are retracting this article because of undisclosed competing interests involving the handling editor and a reviewer. As a result, PNAS cannot be confident that the manuscript received an ...