How a giant tortoise could help you live longer, brain zapping to treat depression, and a male contraceptive trial. Plus, dark fluid could be the explanation for dark matter and dark energy, maybe.

Chinese scientists report editing the genome of human embryos, the role of oxytocin in human/dog relations, chimps that hunt with spears, unexpected bacterial complications in organ transplants, another magma chamber found at the Yellowstone supervolcano and celebrating 25 years of Hubble.