Entomologist Sarah Han has always been into spiders. "I grew up in California and there are a lot of black widows," says Han. "I would keep them as pets. One day, one of them escaped. That's a mistake ...

During the cold and quiet winter, most insects and their predators vanish from sight. But tucked into silken sacs under pear tree bark, some tiny hunters are very much awake. These are Clubiona ...