HIKES Lake Mead, North Bowl of Fire: Tuesday, hike six to seven strenuous miles through the mountains of sculpted sandstone to an overlook of the Muddy Mountain Wilderness. High-clearance vehicle is required. Contact the Alan Bible Visitor Center at 293-8990.

By KEITH ROGERS REVIEW-JOURNAL When Steven Theodore and his son, Evan, set out on a hike on a cool, September morning last year at Valley of Fire State Park, they didn't know they had crossed paths with a bunch of squirrellike animals that had scampered up a sand dune 175 million years ago.