For the first time ever, the genome of a knotty sea spider was sequenced in high resolution. Prashant Sharma / University of Wisconsin Though sea spiders have thrived for millions of years in a ...

When a spider bites, it typically leaves two puncture marks on the skin, a hallmark of arachnid encounters. In the United States, there are over 3,500 species of spiders, but only a handful are known ...