Zion's Navajo Sandstone Shuttle Bus: Jurassic Desert Life on Wheels

From Park Paleontology News*, Vol. 15, No. 2, Fall 2023. By Robyn Henderek, physical scientist, Zion National Park.*

An electric fleet

With a $33 million grant from the U.S. Department of Transportation, and support from partners including the Zion Forever Project, the National Park Foundation, the Utah Department of Transportation, Utah Clean Cities, Iron and Washington Counties and the town of Springdale, Zion National Park has begun replacing its decades-old propane shuttles with an all-electric bus fleet. The new buses will:

• cut greenhouse gas emissions;
• make far less artificial noise;
• carry more riders and serve visitors more efficiently;
• make Zion Canyon more accessible to people of all abilities.

A theme for every bus

The new fleet was a chance to refresh the shuttles' look. Park managers chose a distinct theme for each bus, so the buses are easy to tell apart on the road and each one tells part of Zion's story. Because Zion Canyon's signature rock is the Navajo Sandstone, it was one of the first themes. The evidence suggests that among its ancient dunes were desert oases supporting a thriving ecosystem — so the bus could show life in a place usually imagined as barren.

The artist

Through Zion Forever Project, the park's official non-profit partner, paleoartist Brian Engh was commissioned to design the bus. He is well known among paleontologists for scientific reconstructions of ancient animals and landscapes, and he works from real fossil material: to draw the drooping curve of Otozamites leaves, for instance, he built a model frond. Park staff and Engh planned a wrap along the whole length of the bus, showing the plants and animals that lived on the dunes 190 million years ago.

What the bus shows

The Navajo Sandstone mostly preserves trace fossils — tracks rather than bones — but tracks say a great deal about where their makers lived.

3D model of the Brasilichnium trackway found in the Navajo Sandstone of Zion, with its prints labelled B-1 to B-14. NPS model by Scientists in Parks intern Conner Bennett.

• A burrow. In 2018 a visitor leaving a canyoneering route found a Brasilichnium trackway on a Navajo Sandstone block that had fallen from hundreds of feet up and split along a bedding plane. Tritylodonts, mammal-like reptiles, are among its possible makers, so the bus shows Brasilichnium tracks leading to a tritylodont burrow, the animal peering out over the desert. The burrow is drawn in cross-section to show the sandstone's cross-bedding, left by moving dunes, linking what visitors see in the cliffs to the ancient landscape. The back of the bus also asks riders to Leave No Trace — unlike the Jurassic trackmakers.
• A meal. Two carnivorous coelophysoid theropods — likely makers of Grallator tracks — one holding a lizard-like sphenodontian in its jaws.
• A family. Plant-eating Seitaad feeding on Otozamites leaves.
• An oasis in the background, where water — the ecosystem's lifeblood — would have drawn animals struggling to survive in the dry landscape.
• A resting giant. Inspired by rare crouching Eubrontes tracks at the nearby Johnson Farm Tracksite in St. George, Utah, the bus shows a large, colourful Dilophosaurus — a likely Eubrontes trackmaker — resting its forearms in the sand.

Engh had worked in many media, but never within the limits of a vehicle; he designed the scene around the wheel wells, windows and front doors.

For decades to come

The Navajo Sandstone bus is expected to run for decades, carrying millions of visitors through the park. By showing the ancient life preserved in the canyon walls, the park hopes it will spark wonder in the next generation of paleontologists and park rangers who step aboard.

Sources

• National Park Service, "New Navajo Sandstone-Themed Electric Shuttle Bus Transports Visitors Back in Time at Zion National Park," by Robyn Henderek, Park Paleontology News, Vol. 15, No. 2, Fall 2023. https://www.nps.gov/articles/000/new-navajo-sandstone-themed-electric-shuttle-bus-transports-visitors-back-in-time-at-zion-national-park.htm
• Zion National Park, "Zion National Park receives $33 million federal transit grant." https://www.nps.gov/zion/learn/news/zion-national-park-receives-33-million-federal-transit-grant.htm
• The original's photographs of the bus show artwork commissioned from a private artist by a non-profit partner, and are not reproduced here.
• Words on this page from people and organisations outside the federal government are paraphrased; rewritten in hubnx's own words.