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See the free collection of PNAS coronavirus papers and learn more about our response to COVID-19.
See the free collection of PNAS coronavirus papers and learn more about our response to COVID-19.
Front Matter
People are increasingly dividing themselves into social and political factions. Models can hint at how it happens—and maybe offer ways to mitigate it.
Image credit: Dave Cutler (artist).
A computer visualization of the fossilized plant Asteroxylon mackiei could potentially offer clues as to how modern plants emerged.
Image credit: Matt Humpage (artist).
Saltwater is far more abundant on Earth, yet about half of the known fish species live in freshwater. The longstanding question is why.
Image credit: Florian Moser (photographer).
In the News
A study suggests that the central-western Greenland Ice Sheet (GIS) is approaching a critical transition and will undergo significantly enhanced melting in the near future.
Image credit: Pixabay/mariohagen.
A study explores how white bar formation in clownfish may be tied to differential recruitment in and adjustment to different sea anemone species.
Image credit: Pauline Salis.
Genetic analyses reveal that the Sudanese Kordofan melon is the closest relative and may be a precursor of domesticated watermelons.
Image credit: Shan Wu.
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Science Sessions Podcasts
Maggie Wagner and Manuel Kleiner report that the interaction between maize and soil microbes influences hybrid vigor.
Featured Profile
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Profile of NAS member and molecular biologist Howard Y. Chang
Image credit: Howard Hughes Medical Institute.