Scientists, students and volunteers are descending on the Golden Gate National Recreation Area this Friday and Saturday to record as many plant and animal species as possible in 24 hours. It's part of an event called a BioBlitz.
Traditional bioblitzes often include scientists intensively collecting specimens over a 24-hour period. That takes special equipment and, depending on the species and the park, special permits. But with help from smartphones, just about anyone can produce a remarkable quantity of usable data.