Joe Palca Joe Palca is a science correspondent for NPR.
Joe Palca, photographed for NPR, 17 January 2019, in Washington DC.
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Joe Palca

These mutant nematode worm embryos are genetically identical, but fluorescence imaging shows they are not exactly the same. The pink spots are mRNA molecules involved in gut development. Some twins have spots and some don't, which means some will develop guts and others won't. Arjun Raj hide caption

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Arjun Raj

Identical Twins Are Not Truly Identical

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Scientific Tinkering Leads To New Cell Insight

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A technician works on a Toyota Prius hybrid at a production facility in Aichi Prefecture, Japan. According to experts, cars like the Prius are the next step in a future that's moving toward vehicles with more robotic-type control systems that can analyze driving conditions and act accordingly. Kyodo/AP hide caption

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Kyodo/AP

A thin (0.1 mm) layer of water that is frozen and examined under polarized light. Courtesy of Rainer Stahlberg and Gerald H. Pollack, University of Washington hide caption

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Courtesy of Rainer Stahlberg and Gerald H. Pollack, University of Washington

The bdelloid rotifer Philodina gregaria. Bdelloid rotifers are tiny invertebrates that reproduce asexually. Courtesy of Micrographia hide caption

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Courtesy of Micrographia

Researchers dyed sperm from each deer mouse a different color; in this case, red represents one male and green another. The sperm joined together with their own kind, as seen here, allowing them to swim faster than those that did not cluster together. Heidi Fisher hide caption

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Heidi Fisher

A two-dimensional representation of E8 symmetry, the type of symmetry exhibited by particles in the study. John Stembridge hide caption

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John Stembridge

Scientist turned director Valerie Weiss discusses a scene with cinematographer Jamie Urman on the set of her film, Losing Control. Courtesy of Richard Salazar hide caption

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Courtesy of Richard Salazar

Filmmaking Scientist Experiments With Comedy

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Of Fish And Flies: The Evolutionary Role Of Genes

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Stockholm Visit Worth More Than A Nobel

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