Science

• The Complex Social Lives of Viruses

  New research has uncovered a social world full of cheating, cooperation, and other intrigues, suggesting that viruses make sense only as members of a community.

• How Big Dairy Took Over Your TikTok Feed—With Help From Uncle Sam

  A vast constellation of celebrities, from Kelly Ripa to the McDonald’s mascot Grimace, have helped push dairy sales.

• There’s New Hope for an HIV Vaccine

  A trial vaccine has succeeded in generating low levels of antibodies needed to target HIV. It’s a first but much-needed step toward preventing infection.

• Lab-Grown Meat Is on Shelves Now. But There’s a Catch

  A store in Singapore is selling lab-grown chicken, but it contains only 3 percent animal cells.

• Wegovy Can Keep Weight Off for at Least 4 Years, Research Shows

  Users receiving weekly injections saw their weight fall, plateau, and stabilize over the course of a four-year trial—but it’s still unclear how long these effects last after stopping taking the drug.