Archive for July, 2017


Tijeras Pueblo Overlook

I’ve written some posts before on the interesting recent research being done on the analysis of DNA and stable isotopes to study the genetics and subsistence of the turkeys of the prehistoric Southwest. A recent short paper adds an interesting dimension to this research, by looking at these issues in a sample of turkey remains from a site on the fringe of the Pueblo world, near its interface with the Plains.

The site in question is Tijeras Pueblo, in the Sandia Mountains just east of Albuquerque, New Mexico. The researchers were interested primarily in looking at the stable isotope chemistry of these turkeys to determine whether they primarily ate maize or wild plants, to try to determine how they were raised. In addition, they looked at the DNA of a subset of them to see if they belonging to a previously identified genetic line of domestic turkeys identified in the prehistoric Southwest, or to a separate line associated with modern wild turkeys. In theory, one might expect that turkeys that ate maize belonged to the domesticated line and ones that ate wild foods belonged to the wild one.

In fact, however, what they found was more complicated and interesting. The turkeys fell into two groups which were quite distinct in their chemistry: one that seemed to have eaten maize and another one that seemed to have eaten wild plants. However, the latter group did not have chemistry quite the same as that of the modern wild turkey specimens they compared it to, and was instead somewhat “intermediate” between the maize-fed ones and the wild ones. This suggested to the authors that these turkeys may have been free-ranged, eating a mix wild plants, some maize, and perhaps also insects, and that some of this free ranging may have been in the cornfields for pest control. Similar husbandry practices are documented in the modern Pueblos but had not previously been identified prehistorically.

Even more interesting, however, was the genetic data. Despite the sharp distinction between subsistence strategies implied by the chemical evidence, almost all of the tested specimens belonged to the domesticated ancient Southwestern lineage, and not the wild one. This suggests that the difference in husbandry practices did not correlate to separate origins of the turkeys, but to something different.

Comparisons to specimens from other areas shed some light on possible reasons for this pattern. The researchers compared these turkeys to some from the Albuquerque area, from the Gallina area, and from Arroyo Hondo Pueblo to the north in the Northern Rio Grande area. Since Tijeras Pueblo is at a relatively high elevation where maize agriculture is somewhat marginal, it might be expected that this environment explains part of the difference in turkey husbandry. And when compared with the nearby but much lower Albuquerque samples and the more distant but comparably high-elevation Gallina ones, there is some evidence for this: the Albuquerque samples grouped with the maize-fed Tijeras ones, and most of the Gallina samples grouped with the free-range Tijeras ones. However, the Arroyo Hondo samples, though also high-elevation, showed a much more maize-based pattern, so there is something more than environmental difference going on here.

The authors suggest that the position of Tijeras Pueblo on the eastern fringe of the Pueblo world, at its interface with the very different cultural world of the Plains, may account for the diversity of the turkey husbandry types shown in their data. Conversely, Arroyo Hondo was further within the Pueblo world, while the Gallina region was culturally distinct in ways that are still poorly understood. The authors recognize, however, that further research will be necessary to flesh out the context of these results. In any case, this is a very interesting paper that adds another little bit to our knowledge of the past.

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