In the July 7 SN: The impact hypothesis that won’t die, CAR-T cell therapy upgrades, bad news for Antarctica, a quoll conundrum, honeybees know zero, how volcanoes kill, Jupiter’s polar lightning and more.
MONARCH BEWARE As the climate changes, lovely tropical milkweed popular in gardens may become even more of a danger to monarch butterflies than it is now.
Warren Price Photography/Shutterstock
ROVING RIVERS An updated map of the world’s rivers and streams reveals their global fingerprint. Colors denote a river’s width, from deep blue (30 meters) to yellow (thousands of meters).
G. Allen and T. Pavelsky/Science 2018
WHERE’D THEY GO? About 13,000 years ago, during the Pleistocene Epoch, bison, mammoths (illustrated) and other large mammals roamed North America. Researchers continue to argue over what caused their extinction.