Friday, June 26, 2015

A Recent Find

Earlier in the month, I volunteered to help the Colorado State University field school when they conducted an excavation at a nearby site here in Douglas County. It's common for archaeology field schools to take their students to archaeological sites other than the one they are working on to broaden their exposure to other site types and materials. Another volunteer and I who are familiar with local archaeology helped by taking the students to some local sites after their work day was done.

On one of these visits to a site located on County Open Space lands, one of the students saw what she identified as an odd-looking biface on the site surface (see picture). Having previously worked in the Great Basin and California I was able to identify this as a Paleoindian crescent tool, an artifact rarely found here in Colorado. These date to about 8 - 12,000 BP and here is a short article about them.

Here is a picture of a crescent we found on one of my projects in the Mojave Desert in California about ten years ago.

The current theory is that most of these were actually used as projectile points on atlatl darts. They were mounted transversely with the concave end oriented as the "tip" of the point. It is believed that these were used for hunting water fowl. In the late Pleistocene, the Great Basin and California were covered with many large permanent lakes (Great Salt Lake is a shrunken remnant of one of these) that would have teemed with millions of ducks, geese and swans. Research has shown that these crescents are usually found near the shores of these extinct Pleistocene lakes (the one we pictured above from California certainly was) and excavated sites containing them have significant quantities of water fowl bone.

If you are interested in learning more about this artifact type and its likely role in the peopling of the Americas, I recommend you watch this YouTube video of a lecture given by Dr. Jon Erlandson of the University of Oregon a few years ago. If you watch, stay on through the Q & A period at the end which contains lots of information. If you really want to dig in, you can go here and buy a copy of a comprehensive article on them by Dr. Madonna Moss and Erlandson published in the Journal of World Prehistory in 2013.

As I alluded to earlier, these are extremely rare in Colorado, where we didn't have those large Pleistocene lakes. The Moss and Erlandson article contains a distribution map that shows two in our state and one each in Wyoming and New Mexico. Asking around to knowledgeable people, I have been able to find a picture of one from a private collection in northeastern Colorado. We certainly would have had water fowl here, but not in the huge numbers that would have merited devoting a large number of distinctive projectile points to hunting them. The site this one was found on is located near a confluence of two major creeks, but not near any lake.

I am also intrigued by the fact that this crescent is made of a locally sourced petrified wood. It was locally made, and not some exotic object traded in from elsewhere. Did the person who made this travel to the Great Basin where he found out about crescents and come back to make one? Or migrate from the Great Basin to here, perhaps? Interesting to speculate.

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