The largest fossil spider uncovered to date once ensnared prey back in the age of dinosaurs, scientists find. The spider, named Nephila jurassica, was discovered buried in ancient volcanic ash in Inner Mongolia, China. Tufts of hairlike fibers seen on its legs showed this 165-million-year-old arachnid to be the oldest known species of the largest web-weaving spiders alive today — the golden orb-weavers, or Nephila, which are big enough to catch birds and bats, and use silk that shines like gold in the sunlight. The fossil was about as large as its modern relatives, with a body one inch (2.5...