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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
Did the Caribbean sweep into the western Amazon millions of years ago, shaping the region’s rich biodiversity?
Image credit: Tacio Cordeiro Bicudo (University of São Paulo, São Paulo, Brazil), Victor Sacek (University of São Paulo, São Paulo, Brazil), and Lucy Reading-Ikkanda (artist).
Settlements 4,200 years ago may have suffered from overpopulation before drought and lower temperatures ultimately made them unsustainable.
Image credit: Andrea Ricci.
Better explicating the strengths and shortcomings of these models will help refine projections and improve transparency in the years ahead.
Image credit: Witsawat.S.
In the News
Some songbird parents might improve their own fitness by manipulating their offspring into leaving the nest early, at the cost of fledgling survival, a study finds.
Image credit: Gil Eckrich (photographer).
Moth wing scales, which are used for camouflage against bats, act as ultrasound-absorbing metamaterials, according to a study.
Image credit: Simon Reichel, Thomas Neil, Zhiyuan Shen, and Marc W. Holderied.
A study finds that bees display an awareness of their own body size and shape as they navigate obstacles during flight.
Image credit: Charlotte Doussot.
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Science Sessions Podcasts
Mara Reed and Michael Manga explore why Yellowstone's Steamboat Geyser resumed erupting in 2018.