Recent studies in mice suggest that how the egg cells hold onto and get rid of their proteins may be key to this survival. Although most proteins are renewed every few days, two studies show that some ...

Mammalian organs, including the lung and the kidney, often use a branched design to maximize their functional capacity and efficiency. Lung formation requires two developmental processes: branching ...

Over 4 million premature deaths per year are attributed to air pollution, most of which are in low- and middle-income countries where residents do not have access to reliable information on air ...

Chickens are the world’s most numerous domestic animal. In order to understand when, where, and how they first became associated with human societies, we critically assessed the domestic status of ...

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, ...

In research using laptop screens, cats quickly learned to associate sounds and animations. Image credit: Sheila Fitzgerald/Shutterstock.

PNAS provides free and immediate access to PNAS content in lower-income areas of the world. PNAS is committed to providing full and immediate access to current scientific research across many fields ...

When Carl Linnaeus invented binomial nomenclature in the 18th century, it provided a universal language for scientists. Giving each species a unique name is essential for effective communication, ...

The study of human behavior traditionally focuses on the here and now. After all, people cannot take surveys or participate in experiments if they are not alive today. Here, we propose a way to ...

PNAS may distribute embargoed copies of an accepted article to the press prior to publication. Embargoes expire at 3:00 PM US Eastern time, Monday of the publication week. Authors may talk freely with ...

Plasmonic materials have been touted as ideal photocatalysts due to their extremely large optical cross-sections and ability to generate uniquely energetic nanoscale environments. However, many ...

Debris flows are fast-flowing and dangerous slurries of soil and water that often form when intense rainfall soaks hillsides burned by wildfire. As climate change intensifies this hazard, models ...