Front Matter

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• Opinion: In the wake of Paris Agreement, scientists must embrace new directions for climate change research
  The agreement is an admirable first step, but scientists must come to terms with both its research and policy implications. Image courtesy of Flickr/jmdigne.

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• Inner Workings: Will hagfish yield the fibers of the future?
  Researchers are looking to capitalize on the extraordinary slime that the proto-fish secretes, which consists of remarkably strong threads. Image courtesy of Andra Zommers and Douglas Fudge.

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• Core Concept: Basket trial approach capitalizes on the molecular mechanisms of tumors
  Some researchers, taking into account cancer’s heterogeneity, believe basket trials will help them better identify the populations most likely to benefit from a given drug. Image courtesy of Jane Ades (National Human Genome Research Institute, Bethesda).

PNAS in the News

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• How bumblebees detect electric fields
  Small, vibrating hairs may explain how bumblebees sense and interpret electric fields, according to a study.
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• Beer brewing in ancient China
  Archaeological artifacts from a site in northern China suggest a 5,000-year-old recipe for beer, according to a study.
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• Leaping eels lend credence to Humboldt’s legend
  Experiments with electric eels housed in an aquarium lend support to a centuries-old account of eel fishing by the German naturalist Alexander von Humboldt, according to a study.
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