Meiosis is the process by which a single diploid cell produces four haploid cells, each carrying one copy of each chromosome. In males, all four of these haploid cells become sperm, whereas, in ...

Cultural ecosystem services (ES) are consistently recognized but not yet adequately defined or integrated within the ES framework. A substantial body of models, methods, and data relevant to cultural ...

It’s a late-May morning in the misty mountain town of Monteverde, Costa Rica, and plant ecophysiologist Sybil Gotsch is climbing a very tall tree. Suited up in a red helmet and harness, she uses a ...

As early-career researchers, we are acutely aware that while behavioral science research typically focuses on Western populations, it aims to draw universal conclusions about human behavior. We were ...

Edited by Lawrence Goldstein, University of California at San Diego, La Jolla, CA; received June 16, 2024; accepted July 16, 2024 ...

Igor Dawid in his office at the NIH in 1996. Igor joined the National Cancer Institute (NCI) at the NIH, Bethesda, MD, in 1978. He became head of the Section on Developmental Biology at the National ...

In today's digital age, effectively communicating and promoting your research through the appropriate channels is crucial for ensuring your work reaches your intended audience and garners the ...

PNAS is one of the world's most-cited and comprehensive multidisciplinary scientific journals, publishing more than 3,500 research papers annually. The Proceedings of the National Academy of Sciences ...

As a signatory to the San Francisco Declaration on Research Assessment, PNAS is invested in improving the evaluation of scholarly research outputs. We track a range of article and journal metrics, ...

The optical properties of microstructures on butterfly wings are well studied in the visible spectrum, providing an understanding of the origins of structural coloration. Meanwhile, there is a need ...

PNAS publishes exceptional research in all branches of the biological, physical, and social sciences. In addition to research, PNAS publishes Front Matter, Perspectives, and more.

Large volumes of liquid water transiently existed on the surface of Mars more than 3 billion years ago. Much of this water is hypothesized to have been sequestered in the subsurface or lost to space.