National Geographic : 2012 Jul
NOW PHOTOS: MICHAEL SHEEHAN WASPS ; SUE O'CONNOR. GRAPHIC: ÁLVARO VALIÑO. SOURCE: USGS Wonder Wasp A small number of species, including humans, primates, and some wasps, have a special skill for learning faces. About Face We know that paper wasps can deliver many mighty stings. Now research shows that one type, Polistes fuscatus, can also distinguish among wasps' faces, indi- cating it has brains in addition to brawn. When charged with choosing between pictures of two dif- ferent wasps, the insects identified the image linked to a reward 74 percent of the time, says biolo- gist Michael Sheehan. When pictures of caterpillars---their prey---were swapped in, the success rate plummeted to 53 percent. Sheehan tweaked the wasp photos (such as bottom row, center) and retested. This time the bugs flopped. The upshot? If facial features are intact, these social creatures can spot a face in the crowd. ---Catherine Zuckerman ANCIENT ANGLERS Deep-sea dinners have been on our menus since the Stone Age. That's what Sue O'Connor of the Australian National University learned when Timor-Leste's Jerimalai shelter---home to Pleistocene-epoch humans---yielded 42,000-year-old bones from tuna and other species. The site also surrendered the world's oldest fishhook (left). As many as 23,000 years ago, it was fashioned from a sharpened snail shell, likely strung with bait, and used to snare reef fish. O'Connor says the bones and hook show "that early modern humans had advanced maritime skills," helping them reach Australia some 50,000 years ago. ---Jeremy Berlin 57% of natural diamonds mined each year become jewelry. The other 54.6 million carats are used in industry.