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See the free collection of PNAS coronavirus papers and learn more about our response to COVID-19.
Front Matter
Intact ecosystems have a big role in sequestering carbon. Hence, safeguarding the biosphere from further degradation is an existential challenge for humanity.
Image credit: Shutterstock/Kritskiy-ua.
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).
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
Profile of NAS member and molecular biologist Howard Y. Chang
Image credit: Howard Hughes Medical Institute.
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