“I told him to wait right there and was only in the restroom for like 3 minutes,” you explain to the guide at the visitor booth. You and your parents are completely freaking out because you have lost your little brother at the Rookery Bay National Estuarine Research Reserve. “We will find him,” the guard assures you, “but we need to split up and begin by retracing your steps through the exhibit. Maybe he returned to a part he really liked? I don’t mean to alarm you, but we must find him before dusk when the mangroves become dangerous.”