A Collared Lizard for World Lizard Day

I was thinking and planning my next post on our recent trip to the Pacific Northwest, but was getting writer's block. I caught a post from the Ash Meadows National Wildlife Refuge that today was World Lizard Day. I don't know how such things are determined (there is also a Collect Rocks Day), but it was enough to make me look for the best picture I could remember taking of a lizard. It was a Collared Lizard (Crotaphytus collaris) that I saw during a field trip stop at Canyon of the Ancients National Monument in southwest Colorado.

Lizards evolved in late Permian or Triassic Time (~250 million years ago). They were part of the dinosaurian ecosystem, but they are not closely related to dinosaurs having split off from more primitive reptiles before the dinosaurs evolved. In a sense birds are closer relatives to the dinosaurs than lizards are, given that birds directly evolved from a group (the theropods) within the dinosaur clade. There are about 6,000 species of lizard in the world today, and they occupy habitats from tropical rainforests to the tundra.

Headed into the Back of Beyond (Again)

I had hoped to finish our blog journey through the most dangerous plate boundary, but there was just too little time between real-world trips. The next journey is taking me and nearly two dozen students on a trip through time, both geological and anthropological. Our combined geology and archaeology class is exploring the fascinating landscapes of the Ancestral Pueblo people and other groups of the southwestern United States.

Archaeologists learning geology, and geologists learning archaeology. It's a symbiotic educational relationship that enriches students of both disciplines. We've done this trip a number of times, and it seems to get better every time.

This summer equinox picture of Fajada Butte at Chaco Canyon is emblematic of our trip, as we see Cretaceous sedimentary rocks of the Mesa Verde Group making up the cliffs and slopes. In the foreground, a small ruin from the people who lived on this land for more than a thousand years as a distinct culture. They then abandoned the region and 700 years later, a different group of people started to build roads again, with an asphaltic covering material (and mechanical air conditioning in their dwellings).

And all of the students are willing to dabble a bit in biology as well, especially when the object of their attention is so colorful.

Geotripper is going to be hit and miss for the next few weeks. I look forward to sharing our adventures in a few weeks!

The Abandoned Lands...A Journey Through the Colorado Plateau: The fusion of geology and architecture, part 1 (and a gratuitous lizard photo).

A Collared Lizard at Castle Rock Pueblo

OK, the lizard was an attention getting device...what I really want to talk about is the stunning beauty that resulted when the Ancestral Pueblo people built their homes in total harmony with the landscape they inhabited. Two places really stand out in my experiences, Hovenweep National Monument on the Utah-Colorado border, and a canyon on Cedar Mesa a bit further west in Utah.

In so many places where humans live, their houses and other buildings are imposed on the landscape regardless of appearance or topography. If the land doesn't conform to the builder's desire, the land gets changed, bulldozed, straightened and groomed. When I first arrived at Hovenweep National Monument and gazed at the structures of the Ancestral Puebloan people, I was struck by how the buildings conformed to the rock.

There is little to be seen of the full extent of the habitations that must have existed here, as many of them remain unexcavated and hidden by sagebrush and debris. Built the most unique structures line the rim of the canyon below the visitor center. It feels like the dwellings and towers grew out of the rock itself. Many of the structures were constructed on top of huge fallen boulders and the buildings follow the contours of the rock.

It is sometimes hard to discern the function of some of the buildings, with the strange placement of doorways and windows. Towers would seem to be used for observation posts, but some of the towers were constructed in the canyon where nothing in particular could be viewed.

Looking across the canyon the twin tower command one's attention, but upon closer inspection, one realizes there is another dwelling inside the big boulder on the right.

There are several rooms in the boulder, and the debris on the top of the boulder suggests there was once a structure on top. I don't really want to be flippant, but I look at these dwellings and I almost imagine Dr. Suess characters living here. Whatever the reasons were for the construction of these wonderful buildings, I have to appreciate the creativity that they represent.

In the next post, I will be getting into the Wayback Machine (does anyone recall that allusion?). It's been a decade or so since I took a walk through a magical canyon on the western edge of the "fertile crescent" of the Ancestral Pueblo people on Cedar Mesa, and discovered a near total fusion of human habitation and rock. It wasn't part of our trip last summer, but it seems to fit the theme of the moment.