As mentioned in my last post on the Painted Hills, this area of Oregon is about so much more than some colorful formations. A little preview at the end of that post last Friday was a short description of the old dairy farm near Mitchell (see above). And it’s from there that we’ll continue our road trip through John Day Fossil Beds National Monument in Oregon.
Travel east from Mitchell on Hwy. 26 toward the monument headquarters at Sheep Rock. You will first come to Picture Gorge, a spectacular cut through stacks of basaltic lavas. The Picture Gorge Basalt is a southern outlier of the great Columbia River Basalt flows to the north. The gorge is named for ancient Native American rock art found on the walls.
To see and photograph some pictographs, drive to the east end of the gorge and park alongside the John Day River. Look up to the walls across the road. From here, if the river is low enough, you can get a much closer look at great rock art alongside the river. Just drop below the road and walk a hundred yards or so upriver, looking for short, smooth walls to your right. A rare pictograph of a salamander can be found.
Midway through Picture Gorge you’ll turn north on Hwy, 19 and drive a short distance to the Sheep Rock Unit. There is a great museum that explains the areas rich fossil heritage. This is an important region of the world for paleontologists. Along with Wyoming’s Green River area, it is where well preserved fossils of ancient mammals, plants and other creatures can be found. These remains, preserved within colorful sedimentary rocks shed off ancient volcanoes that were eroded away long ago, document the explosion of mammalian diversity in the Eocene (56-34 million years ago).
Mammals started off very small, literally in the shadow of dinosaurs. Once the dinosaurs went extinct 65 million years ago, mammals slowly evolved and diversified until an inevitable point. Just as happened with dinosaurs near the peak of their diversity, mammals began to evolve into huge forms. This is well documented in the John Day. In fact, the region has abundant mammal fossils all the way up through the Miocene (23-5 million years ago).
One of the largest mammals of all time was the huge rhino-like brontothere. Enormous ground sloths roamed here as well. Other mammals of the John Day: early horses the size of dogs, camels, a large variety of canids, cats (including early saber-toothed varieties), rodents, even early primates. And it’s not just mammals: huge fossil turtle shells are found.
A very important part of the John Day fossil beds is the amazing variety of plant fossils. This allows the environments in which these animals once lived to be worked out in detail. A period of global warming is documented here, followed by a long slow cooling and drying trend that has continued to the present day. Nowadays of course humans are busy driving the climate in the opposite direction, toward a climate last experienced by those now-extinct mammals of ancient North America.
An Aside: Climate Change – The Debate?
I recall having a group of high school science students at the museum at Sheep Rock. I was showing them the fossils and how they told us the ancient climate was lush and subtropical. On the wall was a chart that showed the estimated CO2 levels in the atmosphere during that period, and how they coincided with the types of plant and animal fossils. A man and his wife were listening off to the side.
Later I heard him telling his wife, “see, what did I tell you? Global warming happened in the past and was natural. We don’t have anything to do with it, even if it was actually happening.” Or words to that effect. I wanted to correct his misinterpretation of the meaning of the evidence but realized it was not a good idea for several reasons. For one thing, a person who uses faulty logic certainly missed something early in their upbringing/education. When they got older they internalized this way of thinking, so that any faulty interpretations they make are perceived to be merely “common sense”. Very difficult to explain anything to such a person.
Though it’s true that a warm, tropical climate is very conducive to a diversity of life, it is the change to those conditions that poses the risk. And that’s especially true for very rapid changes like the one we’re entering now. A transition to an ice-free world is upon us, and we can only pray that it will only be accompanied by a drowning of our coastal cities and dramatic changes to agriculture and water supplies. The worse-case scenarios are much more dire.
Scientists are much too conservative to talk about these darker scenarios with the press. But trust me, they aren’t pretty. Picture enormous clouds of poison hydrogen sulfide gas spewing out of stagnant oceans, killing everything that breathes unless it is hidden underground. There is evidence that this happened during past mass extinctions.
Leaving aside all these sunny thoughts, it’s amazing to think this semi-arid region of grassland looked like present-day Panama in the early Eocene (about 50 million years ago). It had active volcanoes and the coastline was closer. With no Cascade Mountains, there was no rain-shadow effect. The warm Pacific Ocean sent abundant moisture over a lush river-laced landscape dotted with volcanoes. Many of the animals (e.g. camel, rhino & elephant) that during present times are found only in Asia or Africa roamed (in early form) the jungly American wetlands of the west.
Animals like horses and camels evolved here in North America, then migrated across the Bering Land Bridge to Asia and eventually Africa. They went extinct here. Many other now-extinct animals, like brontotheres, oredonts (large & pig-like), creodonts (looked like a cross between a hyena and cat but more heavily built) and nimravids (a sleek & agile saber-toothed pre-cat) all lived, died and eventually went extinct here.
I’ve spent quite a bit of time out here teaching science. After a time, I got to where I could experience that ‘other’ Oregon. Believe it or not, for paleontologists or anyone who sees enough fossils, absorbs enough knowledge, and then quiets themselves while out in the places where the fossils are found, it is possible to time-travel with your mind. You can bring up vivid images of that other world in the silence that surrounds you during semi-meditative states. You actually start to feel the humidity and hear the buzzing of tropical insects. Very cool.
So check out that museum! Right across the road lies the historic Cant Ranch and picturesque Sheep Rock. This is a great place for photos, with the old barns, the John Day River and Sheep Rock begging to be part of your compositions. The rangers run tours of the historic ranch, giving you a picture of the old homesteading days when the west was first being settled by whites and their livestock.
The last part of this series covers the northern part of our loop, including the Clarno Unit of John Day Fossil Beds National Monument. Thanks for reading!