die-offs preserved

I drove away from the far right glaring, garish edge of Nevada at 9:24 a.m. with a large coffee from McDonald’s. Google said my next destination was four hours away, but I’d mapped out my own roundabout route to see more of the backcountry. I passed Great Salt Lake and the immaculate city to its east and the autumn foliage east of that, turned north in Evanston, Wyoming, and took a forgotten highway through several spare and rusting towns … and still rolled to a stop in the parking lot at 1:24 p.m.

I added Fossil Butte National Monument to my itinerary only a few days before I left. I was looking at books on my shelf to see if there was anything I should give to my sister, and I noticed one I plan to keep called “The Lost World of Fossil Lake.” It depicts a subtropical, lush environment 52 million years ago, after the “end” of the dinosaurs, where ancestors of modern-day fish, turtles, crocodiles, horses, bats and other animals enjoyed a prehistoric idyll of a warmer, wetter North America. The book praises the museum at the park’s visitor center, and it didn’t disappoint: Walls of fossils and casts of more rare preservations are on display along with multimedia presentations that document the area’s geology, early Eocene ecosystem and more recent history.

I was there in time to join the park ranger’s 2 p.m. lecture about the five mass extinctions that redefined the Earth. He spoke in scientific detail about the reasons behind cataclysmic die-offs of flora and fauna — and the slow, anarchical resumption of biodiversity that follows — which always involve big changes to the environment, often from volcanism and the rise of carbon dioxide in the atmosphere. There isn’t much volcanism today, relative to the massive magma expulsion in Siberia scientists believe caused the Permian-Triassic extinction 250 million years ago. And our planet hasn’t encountered any asteroids lately (we’d have noticed), but our oceans are acidifying, the coral reefs are bleaching, the ice caps are melting and CO2 levels are rising faster than at any time outside of previous mass extinction events. He only touched on that at the end.

The three children visiting from Australia grew bored and wandered away to stomp on nearby puddles. The ranger mentioned to me later he’d heard an elk bugle in the distance when we’d started talking about ammonites and how they disappeared at the same time as Tyrannosaurus Rex, and sure enough he showed me through a telescope some 20 elk resting on the ground about halfway up the limestone bluff in the distance. Just before I’d arrived at the park a rainstorm washed away the thousand or so bug splats on my car windshield. It sprinkled a bit as the ranger walked us through the late Devonian extinction, but other than that for the three hours I spent there including my hike on the aspen-dappled Nature Trail, I didn’t have any trouble with rain. It only returned and remained during my three-and-a-half-hour drive to Dinosaur Inn in Vernal, Utah, a quiet, well-appointed place to sleep across the street from the Utah Field House of Natural History State Park Museum. It opens at 9 a.m.