Archive for the ‘Outliers’ Category

Animas River, Durango, Colorado

Animas River, Durango, Colorado

The fourth chapter of Crucible of Pueblos discusses the eastern portion of the Mesa Verde region, essentially the northern portion of the watershed of the San Juan River from the La Plata drainage east to the San Juan headwaters. This area has seen less research than some other parts of the Southwest, but several major salvage projects in recent decades have added a lot of data on Pueblo I period settlement in particular. The most important of these has been the Animas-La Plata Project associated with the inundation of Ridges Basin to create Lake Nighthorse south of Durango. These projects haven’t revolutionized our understanding of the Pueblo I period the way the Dolores Project did in the Central Mesa Verde region in the 1980s, but they have added large bodies of systematically collected data to broaden our understanding of the period.

The picture that emerges from this evidence shows the Pueblo I period to have been a dynamic, complex time in this region. Indeed, in some respects “chaotic” might be an appropriate descriptor. Population movement, both within the region and between it and other regions nearby, was frequent, sites were short-lived, and evidence for violence is abundant. The population fluctuated wildly but was never very large compared to other areas, but even this small population seems to have been culturally and perhaps ethnically diverse, which may have contributed to the instability and violence. Some of the earliest aggregated villages in the northern Southwest arose in this region during the eighth century AD, but they all appear to have been highly unstable: none lasted more than a few decades, and most appear to have met violent ends. Perhaps relatedly, these villages never held more than a small portion of the overall regional population, in contrast to early villages in some other regions. By the end of the Pueblo I period around AD 900 most parts of the region were largely depopulated, with the residents apparently moving primarily to the south, where many of them likely ended up at Chaco Canyon and were involved in the rise of the Chaco Phenomenon over the course of the tenth and early eleventh centuries.

The authors of this chapter divide their region into four “districts”: La Plata, Durango, Piedra, and Navajo Reservoir/Fruitland. While showing similarities in material culture suggesting connections with each other, the districts have markedly different demographic trajectories, and it seems clear that there was significant population movement among them over the course of the Pueblo I period.

Despite an earlier Basketmaker II occupation, Basketmaker III period settlement was limited to nonexistent in most of the districts, implying that the Pueblo I occupation was primarily the result of migration into the region. Only the La Plata district shows clear evidence for a small BMIII occupation, and even this is probably too small to account on its own for the larger population in the district during Pueblo I. It appears, then, that beginning in the AD 720s there was a migration of people into the La Plata and Durango districts, probably from the south. Site densities increased markedly around 750, especially around Durango, suggesting a further wave of migration, again from the south. It was at this time that the earliest villages began to develop in these areas, although most of the population continued to live in widely scattered hamlets and individual residences. These villages were short-lived and seem to have collapsed in the early 800s, in some cases with evidence for intense violence including, at Sacred Ridge in Ridges Basin, the earliest evidence for the sort of “extreme processing” (probably including cannibalism) of human remains that would recur periodically in later periods of Pueblo prehistory.

The collapse of the early villages in the Durango district appears to have coincided with a general depopulation of that district, with residents emigrating in multiple directions. Some went west and appear to have contributed to the rise of large villages in the Central Mesa Verde region, particularly in the Dolores area, where one large and well-documented community, Grass Mesa Village, shows evidence in its material culture for strong ties to the east. Other Durango people may have gone south into the Frances Mesa area in the lower Animas River valley, possibly mixing with other groups migrating north at the same time. This occupation was short-lived and may have ended with the people moving north into the Dolores area to join the villages there. Some Durango people may also have gone east to form the first Pueblo I occupation in the Piedra district, although this area has seen less research than others and the picture isn’t as clear. Recent surveys do suggest that the Piedra was somewhat marginal to developments elsewhere in the region during Pueblo I, and that its population was both smaller than had been thought and mostly limited to the late Pueblo I period. The fate of the La Plata population is less clear, but there is a definite decline in site numbers after AD 800 coinciding with an increased number of sites in the Mancos River drainage to the west, suggesting emigration to the west there as well.

Chimney Rock Great House

Chimney Rock Great House

As it turned out, the Dolores villages weren’t very stable either, and after their collapse in the mid- to late ninth century people seem to have migrated back into the eastern Mesa Verde region. A surge of immigration into the Fruitland/Navajo Reservoir district after about 880 contributed to the highest regional population of the whole Pueblo I period, although it still wasn’t very high (3,000 people at most regionwide, and likely more like 2,000). The Piedra district also saw a considerable increase in population at this time. The Fruitland/Navajo Reservoir occupation was short-lived, with more evidence of violent ends for some village sites, and it seems that most or all of the people moved south, with at least some of them joining the growing communities in and around Chaco Canyon. There may have been some migration south from the Piedra district as well, but it continued to be occupied into the Pueblo II period after 900. The Piedra people seem to have been somewhat isolated from developments elsewhere in the Pueblo world during early Pueblo II, which is unsurprising given that they were left quite isolated geographically by the depopulation of the Animas drainage and Navajo Reservoir area. They don’t seem to have been completely cut off, however, and ongoing contact with Chaco in particular is suggested by the development of the Chimney Rock great house with its remarkable astronomical alignments in the eleventh century.

There are several noteworthy characteristics of this pattern of settlement and migration, which the authors of this chapter point out. One is the obvious importance of population movement, versus natural increase or decrease, in explaining the wild demographic swings both in the region as a whole and among its individual districts during this period. It was a very dynamic period, when people rarely lived in the same place for more than two or three generations. It’s not clear entirely why, but one reason is likely linked to one of the other noteworthy characteristics: widespread violence, including some of the most extreme violent incidents in the whole archaeological record of the Southwest. Interestingly, much of this violence, including the “extreme processing” incident at Sacred Ridge, appears to have been linked to internal conflicts within communities, especially the early villages. This may in turn explain why relatively few people in this region lived in villages, although it still leaves open the question of why anyone did. The authors suggest that one factor may have been the perception of safety in numbers in a chaotic era, although this ultimately proved to be illusory. It’s not clear to what extent warfare between communities was actually occurring, however, and the widespread popularity of a scattered settlement pattern suggests it may not have been that major a concern for most people. On the other hand, palisades around individual residents units are fairly common in the region, so it may be primarily a matter of different strategies for dealing with violence.

One other noteworthy thing about the violence is that the “extreme processing” phenomenon appears to have been exclusive to the eastern Mesa Verde region during this period. This is interesting because in later periods it occurs in other regions, most notably in the Central Mesa Verde region during the mid-twelfth century, where it is possibly associated with the collapse of the Chaco system. There has been much dispute and discussion about the occurrence of cannibalism as part of at least some of these assemblages, which I’ve discussed at length before. The fact that it appears earliest in the eastern Mesa Verde region during Pueblo I, when it appears to be limited to that region, adds an important piece of context for understanding the phenomenon. While the occurrence of ritual cannibalism in Mesoamerica has led some to look there for the roots of cannibalism in the Southwest, there are some important differences in the apparent practices behind the assemblages that make a Mesoamerican source difficult to document, and if the eastern Mesa Verde region was in fact the part of the Southwest where these practices originated that makes the Mesoamerican connection even more tenuous. While the exact connections between specific Basketmaker and Pueblo populations in different areas are hard to pin down, it’s generally thought that the eastern Basketmakers were both ancestral to later Pueblo populations in the same areas and descended from earlier Archaic populations. Importantly, these eastern groups generally show much less evidence for Mesoamerican influence than western groups, among whom “extreme processing” events are both much rarer and, when they do occur, much later than in the east. Obviously it’s not that there was no Mesoamerican influence among eastern groups, since they did have maize agriculture and so forth, but there’s much less evidence for specific, direct influence than in the west. This implies that “extreme processing,” including cannibalism, may actually have been a practice that developed indigenously in the eastern Mesa Verde region and spread to other parts of the northern Southwest as part of the widespread population movements following Pueblo I.

Finally, the violent and chaotic nature of the Pueblo I period in the eastern Mesa Verde region, whatever the underlying reasons for it, adds some context for the attractiveness of new social formations in other regions, such as the Pueblo I villages in the Dolores area and the emerging great-house communities of early Pueblo II in and around Chaco. While the Dolores villages were not ultimately able to deliver the kind of peace and stability that immigrants from the eastern Mesa Verde region may have been looking for, Chaco apparently was. Furthermore, once Chaco rose to regional prominence in the eleventh century it was able to extend that peace and stability over an unprecedentedly large area of the northern Southwest, including the eastern Mesa Verde region itself. Understanding how the system that emerged in Chaco Canyon was able to achieve this remarkable feat when no one had succeeded at anything like it before is one of the most important questions in Southwestern prehistory, and it is still very much an unanswered one. One important piece of the puzzle, however, is clearly the Pueblo I context in the Chaco area itself, and it is to this that we now turn.

Chaco Street in Aztec, New Mexico

Chaco Street in Aztec, New Mexico

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Utah Welcome Sign

Utah Welcome Sign

The third chapter of Crucible of Pueblos deals with the western part of the Mesa Verde or Northern San Juan region, which basically corresponds to what is now the southeastern corner of Utah. In this context the area is bounded by Cedar Mesa on the west and the Abajo Mountains on the north, as well as by the borders with Colorado and Arizona on the east and south. This is a fairly standard way to define this area archaeologically except that the western boundary is more restrictive than usual, which appears to mainly be a decision based on the near-total lack of sites dated to the Pueblo I period west of the eastern edge of Cedar Mesa. (There are actually Pueblo sites dating to this period much further west in southwestern Utah and southern Nevada, the so-called “Virgin Anasazi,” but they aren’t included in this book at all for some reason.)

The authors divide their study area into a series of physiographic sub-regions based primarily on elevation, which is a useful way to track changes in occupation patterns over the course of the period they discuss. It’s also a different approach to defining sub-regions than most of the other chapters in the book use. These sub-regions are important because the differences in precipitation and growing season length among them seem to have been important factors behind shifting settlement patterns during the period of interest. These shifts seem to have mainly taken place across the region rather than separately in spatial sub-regions such as drainages, as was the case in some other regions.

One way this region differs from others, and especially from the Central and Eastern Mesa Verde regions, is that there has been a relative lack of large-scale salvage excavation projects to provide large amounts of detailed archaeological data. Instead, most data is from surveys and small-scale excavations, and detailed chronological information in particular is missing for most sites that have been recorded. Rough dating of sites to Pecos Classification period at best based on frequencies of a few ceramic types is the norm here, which limits the comparability of data on trends in settlement over time. Nevertheless, the authors of this chapter do their best to come up with a coherent narrative of settlement during the Basketmaker III and Pueblo I periods in this area, which seems to have been an important one for understanding the cultural development of early farming populations and the origins of aggregated villages.

The most striking pattern in the population dynamics of this region in the Basketmaker III and Pueblo I periods is of apparent cycles of population growth and decline on the scale of decades and of greater magnitude than can be explain by internal demographic processes, implying migration into and out of the region multiple times. Most interestingly, these cycles appear to be largely complementary to similar cycles in other nearby regions, especially the Central Mesa Verde region just to the east. This strongly implies that one of the major factors in population changes in both these regions was movement between them.

To go into greater detail, the story told in this chapter begins in the seventh century AD with the expansion of Basketmaker III populations across the region from the narrow area of Basketmaker II settlement along the San Juan River and its major tributaries. The authors attribute this expansion in part to the introduction of beans and pottery, which freed farming populations from dependence on outcrops of limestone to cook with their corn for nitrogen-fixing purposes. Population spread especially into the upland areas with deep soils well-suited to dry farming. Over the course of the Basketmaker III period scattered hamlets began to consolidate into “proto-villages” with public architecture such as oversized pit structures surrounded by scattered households. The authors note the similarity of this pattern to the later Pueblo II great house communities, which is indeed an interesting parallel.

There appears to have been a regional population decline in the early eighth century, although this may be an artifact of the limited data set and difficulty assigning sites to precise time periods. In any case, there is evidence of a noticeable population increase after AD 750, with several villages of tightly clustered households containing public architecture appearing, along with a considerable number of smaller residential sites and a few sites in highly defensive locations, especially at the western edge of the region near Cedar Mesa. The population increase was accompanied by the introduction of a strikingly different type of pottery, Abajo Red-on-orange, which shows many similarities to pottery from the Mogollon region far to the south and likely reflects long-distance migration of some sort. There were still many continuities in architecture and other aspects of material culture, however, which suggests that these migrants combined with local populations rather than replacing them.

The largest and most famous of the villages that developed during this early Pueblo I period is Alkali Ridge Site 13, excavated by J. O. Brew in the 1940s. This site consisted of a series of long, continuous arcing roomblocks, made up of “room suites” of one “habitation” room backed by two smaller “storage” rooms. This is a pattern that would become standard for Pueblo I villages at a slightly later date, and would endure in various forms for centuries. Site 13 consists of six of these arcs, four of which were excavated by Brew. Three of the arcs excavated by Brew also had oversized pit structures with highly formalized features suggesting possible use as public architecture of some sort.

There were other village-sized sites that were established at this time, although few have been excavated. These are among the earliest sites of this size and level of organization in the northern Southwest, and continuities with later sites in other regions suggest they may have been very influential on later developments.

In addition to the early village sites, defensive sites on high, inaccessible promontories began to appear during the early Pueblo I period. These sites have not been studied in any depth, and little is known about them. Some appear to have evidence of extensive residential populations and/or public architecture, while others don’t. One intriguing pattern is an apparent line of them at the western edge of the region along the eastern margins of Cedar Mesa. This, combined with the lack of Pueblo sites to the west, has suggested to some researchers that there was a buffer area or “no-man’s-land” between the Pueblo population in southeastern Utah and early Fremont populations northwest of the Colorado River during this period. It’s worth noting, however, that there were also a few of these apparent defensive sites well within the Mesa Verdean Pueblo region, including the Fortified Spur site near the Colorado-Utah border, so tensions may have been internal as well as external at this point.

During the middle Pueblo I period from AD 825 to 880 there appears to have been a regional population decline, although again this may be due in part to data gaps. It is noteworthy, however, that this is the period of a major population increase in the Central Mesa Verde region to the east, including the formation of the well-known cluster of aggregated villages in the Dolores River Valley, some of which show some striking similarities to earlier Utah villages such as Site 13. It is reasonable to postulate that a pattern of emigration from southeast Utah into southwest Colorado led to this pattern. Southeast Utah wasn’t completely depopulated, however. In addition to scattered small sites throughout the region, there are a very few larger communities firmly dated to this period, including an intriguing site on Elk Ridge called the Pillars that has extensive evidence for middle Pueblo I residential architecture and some tentative evidence for public architecture as well. There are several other sites in the same general area that have more tentative evidence for occupation during this time, and it seems this may have been one of a handful of population clusters in the region during a time of otherwise low population.

After AD 880 population rapidly increased again, and many large villages were built between this point and AD 950. This was a period of rapid depopulation in the Central Mesa Verde region, again suggesting a complementary pattern of migration between the two regions. Many of these new village sites were in highly defensive locations, including some that were nowhere near the frontiers of the region. There is also an intriguing pattern of continuity in location between these early villages and later Pueblo II great house communities from the eleventh century. This pattern is made even more intriguing by two phenomena:

  1. Some of these sites, such as Red Knobs and Nancy Patterson Village, have evidence for masonry roomblocks similar to the “proto-great houses” known from many sites in New Mexico in and around Chaco Canyon during this same time.
  2. There seems to have been another depopulation of southeastern Utah around AD 950, implying that population at these sites was not actually continuous despite these similarities.

It has long seemed to me that southeastern Utah is a crucial area for understanding Chaco. There are several lines of evidence suggesting that at least some people living in Chaco Canyon and involved in its rise to regional dominance had strong ties to Utah, and I suspect those ties were more important in the emergence of the Chaco system than has been generally recognized. This chapter adds some much-needed context on the earlier history of Pueblo populations in Utah, and to me it strongly reinforces those ideas about the importance of Utah to Chaco. The exact nature of these relationships and their importance is still unclear, and the relatively sketchy data available make it harder to figure out, but it still definitely seems like there is something important here.

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McPhee Reservoir and Mesa Verde Escarpment from McPhee Campground

McPhee Reservoir and Mesa Verde Escarpment

The second chapter of Crucible of Pueblos discusses the Central Mesa Verde region, which is defined as basically the southwestern corner of Colorado, bounded on the west and south by the modern borders with Utah and New Mexico, on the east by the La Plata River valley, and on the north by the highlands north of the Dolores River. This is the region where Pueblo I period villages have been most extensively studied, primarily by the Dolores Project during the construction of McPhee Reservoir in the 1980s and in subsequent research by archaeologists building on that work. As a result, there’s not a whole lot that’s new in this chapter for someone who has been following the literature on this topic, although it does make a good introduction to the subject for someone who hasn’t. It also discusses some parts of the area, especially the northern and eastern fringes, that have seen much less research than the well-studied Great Sage Plain (including the Dolores sites) and Mesa Verde proper. Overall, the data assembled here is among the most detailed and reliable available to analyze demographic trends and population movements during the Pueblo I period in the northern Southwest.

Among the key factors that the authors discuss are the inherent attractiveness of this region to early farmers because of its good soil and relatively favorable climatic conditions compared to other nearby areas. Indeed, this is the only part of the northern Southwest that has seen extensive dry farming in modern times, and it is still primarily agricultural in use. This makes it unsurprising that early farmers would have concentrated here, as indeed they did, starting in the Basketmaker III period ca. AD 600 and increasing steadily in population through about 725. These early sites generally consisted of scattered hamlets presumably housing individual families. Villages, which in this context means clusters of multiple residential roomblocks in close proximity, began to appear around 750, often in association with great kivas, which had previously been rare in this region for reasons that are unclear.

Villages to both the west and east, discussed in subsequent chapters, date to the same period as these early ones in the Central Mesa Verde villages, and there was a striking variety in community organization and layout across the broader region. The dissolution of the eastern and western villages seems to have contributed to an influx of population into the Central Mesa Verde area in the early ninth century, resulting in the largest and densest concentration of population seen to that date. Village layout also became more standardized, with two main patterns dominating, one associated with great kivas and another including U-shaped roomblocks that were likely ancestral to later “great houses.” These villages, most extensively documented at Dolores, were however short-lived, and by the early tenth century the area was almost completely depopulated, with the former inhabitants apparently moving primarily to the south, into the southern part of the San Juan Basin, where they seem to have played a key role in the developments that led to the rise of Chaco Canyon as a major regional center in the eleventh century.

As I said before, none of this is groundbreaking information at this point, and I’ve discussed some of the implications of the Dolores data before. It is however useful to have a synthesis of this region during this important period to refer to, and this chapter works well for that purpose.

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Looking East from Casamero Pueblo

Looking East from Casamero Pueblo

Unmanned aerial vehicles (UAVs), popularly known as “drones,” have become increasingly common in recent years as the technology behind them has developed. Some uses are controversial, such as military applications and uses that might violate privacy expectations or be dangerous to other aircraft, but other uses are more benign and can potentially open up new frontiers.

In archaeology, UAVs are increasingly being used for aerial photography and remote sensing in many places around the world. These are types of research that have been established for decades, but that until recently were prohibitively expensive for most archaeologists since they required both expensive camera equipment and the use of airplanes or helicopters. With the development of both lighter, less expensive cameras and UAVs that are robust enough to carry them, this type of research is now much more practical.

A recent paper by a team of researchers including Jesse Casana of the University of Arkansas and John Kantner of the University of North Florida reported on research using a UAV to take infrared thermal imagery, or aerial thermography, as well as color photography, of sites in the Blue J community south of Chaco Canyon, New Mexico. (Casana has the paper posted on his Academia.edu page.) Kantner has been studying Blue J and the surrounding area for several years and has come up with some interesting results.

Blue J is in an area at the southern edge of the San Juan Basin that is thick with Chacoan outlier communities, most of which date to fairly early in the Chacoan era and many of which were apparently abandoned while the Chaco system was flourishing. Casamero Pueblo is one site very close to Blue J where a great house has been excavated and is open to public visitation. These communities typically have one or more great houses and great kivas, and in fact it is unusually common for communities here to have multiple great houses compared to other Chacoan outlier communities. At Blue J, however, Kantner has so far not identified any great houses or great kivas. As he says on his website:

Turquoise, marine shell, jet, azurite, malachite, and other exotic materials attest to the success of Blue J’s inhabitants. Oddly, however, what was originally thought to be a great house turned out to be a normal residential structure, making Blue J the only community for miles around without Chacoan architectural influence.

Now, part of what’s going on here may have to do more with how archaeologists define “great house” than with anything about Blue J specifically. The function of the monumental buildings that have been given this label remains a point of active contention among scholars, with some arguing that they were primarily residential, perhaps housing community elites or religious leaders, and others arguing that they were non-residential public architecture, perhaps with ritual significance as sites of pilgrimage and/or communal feasting. Kantner belongs to the latter camp, so finding “normal” residential features at a suspected great house removes it from consideration as such, whereas another archaeologist might interpret such findings differently. (It’s worth noting that many if not most excavated “great houses” have showed at least some evidence for residential use, and in some cases they have not been noticeably different from other residential structures in a community except in size and location.)

The focus of the recent study was on demonstrating the potential for using UAVs to do fast, inexpensive survey of large sites and to identify buried features. Blue J is well suited for this on both counts. It is located at the foot of a steep cliff, which has resulted in many sites in the community being covered with substantial deposits of sediment carried by water and wind, making them difficult to identify on the surface. It is also fairly large for a Chacoan outlier community, with over 50 residential sites identified through previous surveys, which makes a fast method of survey over a large area an attractive proposition.

The study consisted of doing several flights with a UAV over the site, at different times of day and night, primarily with the infrared thermal camera to capture differences in temperature that are expected to be present between archaeological features and the dry desert soil. The original intent was to do some of the flights in the hottest part of the afternoon, but high winds ended up making this impossible. The results were nevertheless impressive: one site that had been previously identified through survey and limited excavation showed up clearly in the imagery, with buried walls visible in some of the images. Several other sites that had been identified but not excavated showed up as well, with buried walls again visible. A large circle showing a possible great kiva is particularly interesting given that no great kiva has yet been identified from surface survey.

Obviously further work is necessary to confirm some of the results from the imaging, but this is a very successful demonstration of the potential for this technology to improve survey and site identification so that further research can be focused on the most promising locations for sites. Other sensing techniques such as ground-penetrating radar have also been tried in the Southwest, but they are much slower and can be thrown off by some characteristics of the desert environment. Aerial thermography using UAVs offers another option that seems to have a lot of potential and it will be interesting to see how it is used as the technology continues to advance.
Casana, J., Kantner, J., Wiewel, A., & Cothren, J. (2014). Archaeological aerial thermography: a case study at the Chaco-era Blue J community, New Mexico Journal of Archaeological Science, 45, 207-219 DOI: 10.1016/j.jas.2014.02.015

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Old Bonito from Above

Old Bonito from Above

Having introduced the basics of archaeological use of DNA evidence, and discussed some other applications of DNA studies in archaeology, let’s take a look at the data relevant to the Southwest specifically. For modern populations in North America overall, there are some broad trends that have been identified in mitochondrial haplogroup distribution by region, as first elucidated by Joseph Lorenz and David Glenn Smith of UC Davis in 1996. They only looked at haplogroups A, B, C, and D, since haplogroup X had not yet been identified as a founding haplogroup at that time. Their results showed that there are definite patterns in haplogroup distributions by region. For the Southwest specifically, they found most groups showed very high levels of B and low levels of A, despite the fact that A was the most common haplogroup in their sample overall. The main Southwestern groups that showed high levels of A were the Athabascan-speaking tribes (Navajo and Apache), which is unsurprising since northern Athabascan groups, along with most other groups in the Arctic and Subarctic, are almost exclusively A, and it’s well established that the southern Athabascans immigrated into the Southwest from the north relatively recently. Some other Southwestern groups show some representation of A as well, which Lorenz and Smith attribute to intermixing with the Athabascans (although as I’ll discuss below this doesn’t seem to be the whole story). Similarly, the Navajos and Apaches showed substantial representation of B and C, unlike their northern cousins, and this is probably due to intermixing with the Pueblos and other Southwestern populations.

A subsequent study by Smith, Lorenz, and some of their students at Davis looked specifically at haplogroup X, which had been identified in both modern and ancient Native American samples by then and was established as a founding haplogroup. They found it widely distributed among modern populations speaking a variety of languages but particularly among speakers of Algonquian and Kiowa-Tanoan languages. The Kiowa-Tanoan connection is of particular interest for Southwestern purposes, of course, as this is one of the main language families spoken by the eastern Pueblos in New Mexico. In this case, haplogroup X was found in the Kiowa and Jemez samples. This is very interesting since the Jemez are Pueblo and the Kiowa are not, and the relationship between the Kiowa and the Tanoan-speaking Pueblos is a longstanding mystery. It’s hard to know how to interpret the haplogroup X data in this connection. Since X is so rare overall the fact that it is so concentrated in certain groups seems meaningful somehow, but since it’s still pretty rare in those groups and little follow-up research on this has since been done it remains quite mysterious.

Turning to the ancient evidence, the first work in the Southwest was associated mostly with the University of Utah. In 1996 Ryan Parr, Shawn Carlyle, and Dennis O’Rourke published a paper reporting on aDNA research on the remains of 47 Fremont individuals from the Great Salt Lake area, 30 of which could be assigned to a haplogroup. The Fremont have always been something of a mystery, with many Southwestern cultural features but living on the northern fringes of the Southwest and having some notable differences from Pueblo cultures to the south. What the Utah researchers found, however, seemed to show the Fremont patterning genetically with the Pueblos rather than with other groups in the Great Basin or Plains. Haplogroup A was completely missing from their sample, while B was by far the most common haplogroup and C and D were also present in small numbers. This seems to clearly rule out one theory about the Fremont, which is that they were composed in part of Athabascans on their way south from the Subarctic, and also casts in serious doubt other theories linking them to later cultures on the Plains (where haplogroup A is also very common). It’s true that there is internal cultural variation within the construct “Fremont” and it’s quite possible there was genetic variation as well, but the Great Salt Lake Fremont were the furthest north of the identified subdivisions and the closest to the Plains, so if even they show more genetic similarities to the Southwest that is strong evidence against theories associating them with areas to the north and east.

It’s also noteworthy that the Fremont distribution is in contrast to what Lorenz and Smith found among modern Numic peoples who now occupy the Fremont’s Great Basin home. The Numic Paiute/Shoshone sample that Lorenz and Smith looked at lacked haplogroup A, but it showed a very high proportion of haplogroup D (the highest in their whole study, in fact) and a low proportion of B and C. This doesn’t totally rule out some Fremont contribution to Numic ancestry, but it makes it seem unlikely that there was substantial genetic continuity between Fremont and Numic populations, which supports the “Numic Expansion” hypothesis for the late prehistory of the Great Basin. Smith and his student Frederika Kaestle later published a paper making this exact argument, using not only the Fremont data but additional ancient remains from the western Great Basin to argue that the differences in haplogroup frequencies supported a replacement of the earlier Basin inhabitants by the Numa.

Following up on this research, a subsequent paper by the same Utah researchers added in data from the Anasazi. They successfully assigned 27 Anasazi samples to haplogroups. Of these, 12 were from southeastern Utah, 9 were from Canyon del Muerto, 4 were from Canyon de Chelly, and 2 were from Chaco Canyon. Of the Chaco remains, one came from the debris in Room 56 at Pueblo Bonito, a part of the north burial cluster in Old Bonito which was very crudely worked over by Warren K. Moorehead in the 1890s. The other I can’t seem to find any specific information on. All of the Anasazi remains analyzed in this study were from the collections of the American Museum of Natural History, which makes me surprised that only two Chaco samples were involved. It’s possible that more were analyzed but only these two produced enough DNA to work with. In any case, if in fact there are more Chaco remains at the AMNH that have not yet been analyzed for DNA it would be very helpful to analyze them.

The results of this analysis were consistent with the standard archaeological understanding that the modern Pueblos are the descendants of the Anasazi. B was the most common haplogroup, with smaller levels of A and C. D wasn’t present at all, and two of the specimens didn’t fall into any of the four haplogroups, implying that they might have belonged to X. (The two Chaco samples belonged to haplogroups B and C; the sample from Room 56 belonged to haplogroup B.) Note that A is present here in populations dating well before any likely admixture with Athabascans, which is evidence against Lorenz and Smith’s contention that the presence of A in modern Pueblos can be attributed entirely to mixture with Athabascans.

Based on the dominance of B and low levels of other haplogroups, these researchers concluded that the Anasazi remains they analyzed were not significantly different from the Fremont remains they had analyzed earlier, adding further support to their contention that the Fremont pattern with the Pueblos. Note, however, that the Fremont hadn’t shown haplogroup A at all, while the Anasazi had it at a low but still respectable level (22%). Also, the Fremont showed a low level of haplogroup D, which the Anasazi didn’t have at all. These differences don’t necessarily mean the Fremont and Anasazi weren’t related, of course, but they do show how much that similarity is a judgment call supported by questionable statistics. In this case one big problem with the statistical analysis was treating the haplogroup frequencies as ratio-level data, which implies that they are meaningfully representative of the underlying populations despite the very small and non-random samples. This is highly implausible. This problem means that the authors’ conclusions about whether differences between samples were “significant” or not in a statistical sense is not really meaningful since it can’t reasonably be expected to generalize to the populations, which are what we really care about.

In addition, as Connie Mulligan pointed out in the general paper on aDNA that I discussed previously, the differences that the Davis researchers found between the haplogroup frequencies of the Fremont and Numic samples, which they used as evidence of a lack of population continuity, were actually quite similar statistically to the differences the Utah researchers found between the Fremont and Anasazi, which they interpreted as not being significant! This disconnect goes to show that there’s actually quite a bit of subjective judgment in interpreting results like this, despite the superficial impression of “objective” statistical data.

One way to overcome this confusion would be to increase the number of samples analyzed and try to make them as close to representative of the underlying populations as possible. That would certainly help, but the fundamental problem of defining the ancient population of interest, and the apparent impossibility of analyzing a sample from it that could be assumed to be truly representative, are daunting challenges. A more productive approach, which subsequent research has in fact been following, is to do more in-depth analysis of available samples, so that more detailed data than crude haplogroup assignments are possible.

One way to do more in-depth analysis would be to move away from relying exclusively on haplogroup assignments and look instead at the nuclear genome. Sequencing the whole nuclear genome provides vastly more, and more statistically robust, information than mitochondrial haplogroup assignment, as commenter ohwilleke pointed out in response to my initial DNA post. Most of the studies mentioned in my previous post in other parts of the world have used this methodology, with very informative results. This type of analysis has, however, not been done on ancient remains from the American Southwest to my knowledge. I’m not sure why exactly, but there are various reasons including cost and level of preservation of remains that could account for this lacuna.

Instead, Southwestern researchers have mostly doubled down on mitochondrial haplotype analysis and extended its reach by looking at further mutations within the defined haplogroups to identify sub-haplogroups that can further narrow down genetic relationships. This has been a productive line of investigation, as exemplified by a very interesting paper from 2010 dealing with Chaco-era sites in the area of Farmington, New Mexico.

B-Square Ranch, Farmington, New Mexico

B-Square Ranch, Farmington, New Mexico

The paper, by Meradeth Snow and David Glenn Smith of Davis and Kathy Durand of Eastern New Mexico University, analyzed human remains from two sites on the B-Square Ranch, a large ranch that includes most of the land south of the San Juan River in Farmington. The ranch is owned by the Bolack family, which has long been prominent in local and statewide affairs. Its patriarch for many years was Tom Bolack, who was governor of New Mexico for a brief period in the 1960s and was also well known for his elaborate produce displays at the State Fair. His son Tommy Bolack, who took over management of the ranch when Tom died, has long had an interest in archaeology and did his own excavations in various of the many archaeological sites on the ranch. In recent years rather than continuing his own excavations he has worked with Linda Wheelbarger, a professional archaeologist who teaches at San Juan College in Farmington, to conduct field schools in the summers for SJC students as well as analyses of artifacts and human remains from both these recent excavations and his own earlier amateur work.

Among these analyses was the aDNA analysis of remains that Bolack excavated from the Tommy and Mine Canyon sites, two small-house sites on the ranch dating to the Chaco era. The Tommy site is slightly earlier, dating to approximately AD 800 to 1100, while the Mine Canyon site dates to approximately AD 1100 to 1300. Since the Tommy site seems to have been abandoned at approximately the same time the Mine Canyon site was founded, one obvious interpretation is that the Mine Canyon site was founded by the same people who had previously lived at the Tommy site. The DNA evidence, however, challenges this interpretation and suggests a more complicated story.

For this study, 73 samples were sent to Davis for aDNA analysis. This included a mix of tooth and bone samples. Of these samples, 48 (65.7%) could be assigned to a mitochondrial haplogroup. Of these, 26 were from the Tommy site and 12 from the Mine Canyon site.

The successfully analyzed samples from the Tommy site showed a typical distribution of haplogroups for a Southwestern population: 3% A, 69% B, 14% C, and 14% D. (This study didn’t look for haplogroup X, and all successfully analyzed samples fell into one of the other founding haplogroups.) The Mine Canyon sample, however, showed a very unusual distribution: 58% A, 33% B, 8% C, and 0% D. This is an exceptionally high proportion of haplogroup A, which is generally fairly rare in the Southwest except in Athabascan groups which are generally thought to have arrived in the region well after these sites were abandoned. Haplogroup A is also very common in Mesoamerica, which makes its dominance in a Chaco-associated site particularly intriguing given the evidence for contact with Mexico seen at Chaco Canyon itself and some outlying Chacoan sites.

The authors are careful to note that these are very small sample sizes, which makes sampling bias a very real possibility to account for this sort of striking result. They compare these distributions to several other ancient and modern Southwestern and Mesoamerican populations using Fisher’s exact test and find, unsurprisingly, that the Tommy site sample isn’t significantly different from other ancient Southwestern populations but is significantly different from all the modern populations as well as the ancient Mesoamerican ones. The Mine Canyon sample, on the other hand, was found to be significantly different from all the ancient Southwestern samples as well as all the modern Southwestern ones except the Athabascan Navajo and Apache, while it wasn’t significantly different from any of the ancient or modern Mesoamerican samples. This result is clearly driven primarily by the unusually high proportion of haplogroup A at Mine Canyon, which means it doesn’t really add much to the paper. Although Fisher’s exact test does take into account the small sample sizes, it doesn’t address the more fundamental problem with this sort of use of statistics on this type of data which can’t really be trusted to be representative of the underlying population of interest. This is the sort of thing I was talking about in the earlier post under the somewhat tongue-in-cheek label of “elaborate statistical techniques” on data that don’t necessarily fit the necessary requirements for their use. This sort of technique is not actually very elaborate compared to more sophisticated statistical analyses used for studies of whole genomes, where the number of data points is immense and they can actually be assumed to be representative of the analyzed individual’s full ancestry. Calculating P-values for differences between two samples based on four data points for each, when neither sample is necessarily representative of its underlying population of interest, is not very useful, but very common in mtDNA studies at least in the Southwest. To their credit, the authors of this paper are well aware of the weaknesses of this part of it and are careful to downplay the significance of the statistical analysis.

With these intriguing preliminary results, the researchers attempted further sequencing to identify more specific mutations that might define sub-haplogroups and clarify relationships on a more granular scale. Of the 48 samples that could be assigned to haplogroups, 23 were successfully sequenced for mutations in a region of the mitochondrial genome known to be highly variable. (Note how small the sample gets with subsequent levels of analysis.) Poor preservation was a major problem at this point, and there wasn’t enough genetic material remaining to construct the sort of network diagram that is often included in papers like this, showing specific mutations and the relationships they imply between specific ancient and modern samples.

The most interesting results from this further sequencing were with haplogroup A. Of the 8 samples initially identified as belonging to this haplogroup, 6 samples from the Mine Canyon site showed two distinctive mutations that are otherwise known only from 3 modern Zuni samples, along with one Tohono O’odham and one Chumash sample. Importantly, this set of mutations is unknown from both Mesoamerican and Athabascan groups. This is strong evidence that the dominance of haplogroup A at the Mine Canyon site does not indicate either migration from Mesoamerica or an early Athabascan presence in the Southwest; instead, it seems that this site just happens to have had an unusually high proportion of a rare but natively Southwestern lineage which survived into modern times at Zuni (and may have had some connections further west). The samples belonging to haplogroup B similarly showed the dominance of a sub-haplogroup distinctive to the Southwest and unknown in Mesoamerica.

The differences between the Tommy site and the Mine Canyon site in haplogroup frequencies, while they may well be a function in part of the small sample sizes, may also provide evidence for complex population movements within the late prehistoric Southwest. The exact parameters of these movements can’t be defined until more evidence is available from other areas, however, especially Chaco Canyon and the Mesa Verde region.

Overall, despite the poor preservation of the samples involved, this study provides important support for a finding that has come out consistently across all lines of evidence relating ancient to modern Pueblo people: there is a lot of evidence for continuity over time on a regional scale with complex movements within the Southwest, but little to no evidence of significant population movement into or out of the Southwest in recent centuries. (There is a whole other debate about the extent of population movement into the Southwest much earlier, at the time when agriculture was first introduced, which I haven’t discussed much in these posts and which isn’t of much importance for the specific issue I’m addressing here.) I think there is a lot of potential for more detailed reconstruction of movement within the Southwest based on a combination of lines of evidence, but we’re certainly not there yet.

I’ve gotten some questions about how the DNA evidence relates to the issue of hierarchy at Chaco. I’ll have a more extensive post on the evidence for social hierarchy, which I think is extensive, but the short answer is that DNA doesn’t really provide any evidence one way or the other on this point. Since all evidence points to a general pattern of population continuity in the Southwest at least since the introduction of agriculture, the genetic patterns of any elites that arose wouldn’t be likely to differ in any noticeable way from those of the commoners they rose from. Indeed, the one sample to be analyzed for mitochondrial DNA that is very likely to come from an elite Chacoan context, the sample from Room 56 at Pueblo Bonito, belonged to haplogroup B, the most common in both ancient and modern Southwestern populations. It’s theoretically possible to imagine an elite group immigrating into the Southwest from Mesoamerica, and theories have been proposed along these lines, but the DNA evidence doesn’t particularly support this, and it’s much more likely based on all lines of evidence that the rise of an elite at Chaco was a primarily indigenous development involving some indirect influence from Mexico but little to no permanent population movement over that distance.

This is the last substantive post in my series about “tracing the connections” between the ancient and modern Southwest, although I will probably do a follow-up post linking to all the others for the convenience of readers. Overall, I think these posts have shown that we have substantial evidence from various perspectives that the modern Pueblos are the descendants of the ancient Anasazi (and other prehistoric Southwestern groups), but the evidence we have so far is not sufficient to connect any specific ancient sites with any specific modern pueblos. I am hopeful, however, that that may change as more evidence comes in and we are able to tie together new data with the evidence we already have to make some more specific connections.
Carlyle SW, Parr RL, Hayes MG, & O’Rourke DH (2000). Context of maternal lineages in the Greater Southwest. American journal of physical anthropology, 113 (1), 85-101 PMID: 10954622

Kaestle FA, & Smith DG (2001). Ancient mitochondrial DNA evidence for prehistoric population movement: the Numic expansion. American journal of physical anthropology, 115 (1), 1-12 PMID: 11309745

Lorenz JG, & Smith DG (1996). Distribution of four founding mtDNA haplogroups among Native North Americans. American journal of physical anthropology, 101 (3), 307-23 PMID: 8922178

Smith DG, Malhi RS, Eshleman J, Lorenz JG, & Kaestle FA (1999). Distribution of mtDNA haplogroup X among Native North Americans. American journal of physical anthropology, 110 (3), 271-84 PMID: 10516561

Snow, M., Durand, K., & Smith, D. (2010). Ancestral Puebloan mtDNA in context of the greater southwest Journal of Archaeological Science, 37 (7), 1635-1645 DOI: 10.1016/j.jas.2010.01.024

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Old Bonito from Above

Old Bonito from Above, Including Northern Burial Rooms

So far in this series of posts on “tracing the connections” between ancient Pueblo sites like Chaco Canyon and modern Pueblos, I’ve discussed evidence from linguistics and folklore, but of course if the issue is determining which modern groups are physically descended from which ancient ones it’s hard to beat evidence from actual physical remains. Physical anthropology has been somewhat less emphasized in the history of Southwestern anthropology, especially compared to archaeology and ethnography, but there has been a fair amount of this kind of research over the years and it is clearly at least potentially useful in answering these questions.

These days when people talk about physical evidence of genetic connections they often mean DNA, and there have been several interesting recent studies of the DNA of both ancient and modern Southwestern populations that are relevant to my present concern. That topic deserves its own post, however (which I am working on), so for now I’m going to focus on a more “traditional” type of physical anthropological study: the statistical comparison of skull features and measurements.

This sort of study generally takes the form of measuring various attributes of skulls from different archaeological excavations and comparing them statistically to see which ones pattern together. (There are also studies of non-metric features that work somewhat differently, but here I’m going to focus on studies of metric features.) I’m always a bit dubious about the relevance of these studies, since I’m not sure how clear it is that the traits they’re measuring really do correlate with genetic relatedness, but this is a well-established and longstanding field of inquiry so for now I’ll take it as given that the underlying theoretical assumptions are well-founded.

Old Bonito from West Plaza Showing Plaza Kivas in Foreground

Old Bonito from West Plaza Showing Plaza Kivas in Foreground

Turning to Chaco specifically, the most influential studies along these lines are those done by Nancy Akins as part of the Chaco Project in the 1970s and 1980s. It was her work that famously concluded that the two main burial populations in Pueblo Bonito, in the northern and western parts of the site, were most similar not to each other but to two different small house sites elsewhere in the canyon. This was an important finding, in that it implied that the population inhabiting the canyon in its heyday was physically diverse in ways that didn’t necessarily pattern with geographical settlement patterns. This in turn implies that there may have substantial diversity in ethnic and linguistic backgrounds among different Chaco residents as well, an implication that some other lines of evidence also support.

Akins only compared populations from within Chaco Canyon, however. To evaluate the connections between Chaco and later Pueblo sites, comparable measurements needed to be made of remains from later Pueblo sites and compared to Akins’s Chaco data. The most extensive study along these lines that I know of is in a short article by Michael Schillaci and Christopher Stojanowski published in 2002. Interestingly, this article was actually a comment on an earlier article by Peter Peregrine arguing that Chacoan society was matrilocal based in part on the fact that some modern Pueblo groups, such as the Hopis and Zunis, are matrilocal. (Matrilocality is the practice of newly married couples living with the wife’s parents, and it is apparently very uncommon cross-culturally compared to patrilocality, where couples live with the husband’s parents.)

Schillaci and Stojanowski argue that while it’s certainly possible that the matrilocal western Pueblos of Hopi and Zuni are descended in part from the Chacoans, it’s not at all obvious that they have a better claim to such descent than the eastern Pueblos of the Rio Grande Valley, which are generally either patrilocal or bilocal (couples live with either set of parents). To test this idea, they take Akins’s data from Chaco and compare it to measurements made according to the same protocol on several other contemporaneous and later Pueblo populations. These include Village of the Great Kivas, a Chacoan outlier in the Zuni area, as well as Hawikku, a much later ancestral Zuni site. They also include several samples from the Rio Grande area, both contemporary with Chaco and later.

As expected from Akins’s results, Schillaci and Stojanowski found that the different samples from Chaco don’t particularly pattern with each other. Interestingly, in their analysis the northern burials at Pueblo Bonito stand somewhat apart from all the other samples. This could potentially be evidence that these, the richest burials ever found in the Pueblo Southwest, represent a group that was genetically distinct from most other Southwestern populations, but it’s important to keep in mind that the number of samples being compared here is relatively small and there’s no way to know how representative it is, so sampling error is always a strong possibility when patterns like this show up. (Other studies have found that these remains are well within the range of variation typical of Southwestern populations, so the fact that they stand apart from the other groups in this study probably doesn’t imply that they were immigrants from outside the region or anything.)

Western Burial Rooms in Old Bonito

Western Burial Rooms in Old Bonito

Of the other Chaco samples, the western burials at Pueblo Bonito cluster most closely with those from both Hawikku and the ancestral Tewa site of Puye in the Rio Grande Valley. The burials from the small sites in the Fajada Butte area at Chaco pattern most closely with the ancestral Tewa site of Tsankawi, and in fact these two form a somewhat distinct group compared to most of the other samples. Finally, the burials from the small sites of Bc 51 and Bc 53, on the south side of the canyon across from Pueblo Bonito, pattern closely with those from Picuris, a Northern Tiwa Pueblo which is still occupied, as well as with those from the ancestral Tewa sites of Sapawe and Pindi.

Schillaci and Stojanowski conclude from this that there is no good reason to conclude that Chacoan society was matrilocal based on the practices of the likely descendants of the Chacoans, among whom they have identified both eastern and western Pueblos practicing various forms of postmarital residence. They do acknowledge that they weren’t able to include any Hopi samples in the analysis, so the western Pueblos are represented only by the two Zuni-area sites, which leaves open the possibility that the Hopis are closely connected to Chaco, which would strengthen Peregrine’s position and weaken theirs. On the other hand, other lines of evidence suggested somewhat weaker ties to Chaco among the Hopis than among most other modern Pueblos, so this probably isn’t a major problem. In his response, Peregrine notes the possibility that bilocality among the eastern Pueblos is a post-contact development related to declining population and therefore not necessarily relevant to the prehistoric evidence. He doesn’t challenge the overall validity of the analysis, however, which is our main concern here.

This is an interesting study, and it identifies some later sites with at least a high probability of including people descended from the Chacoans, but the facts that these sites don’t particularly pattern with each other and that there was considerable diversity within Chaco itself point to how complicated the picture seems to be. Overall, this evidence seems to support the idea that most of the modern Pueblos include at least some people who are descended from the Chacoans, and it provides particular support for such ties among the Zuni, Tewa, and Northern Tiwa. It also supports the previously existing evidence for considerable population diversity at Chaco itself. As we’ll see in the next post, this is not very different from where the DNA evidence leads.
Schillaci, M., & Stojanowski, C. (2002). A Reassessment of Matrilocality in Chacoan Culture American Antiquity, 67 (2) DOI: 10.2307/2694571

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Fremont River, Utah

Fremont River, Utah

Today is Cannibal Christmas (for previous installments see here and here), and this time I’d like to discuss some instances of alleged cannibalism well beyond the boundaries of the Chaco system or even the Anasazi culture area. These assemblages are in sites belonging to the poorly defined Fremont Complex of Utah, which is roughly contemporary with Chaco and included people practicing a range of lifestyles including varying amounts of maize agriculture. Beyond those two features, however, the various groups included under the label “Fremont” display so much internal diversity that it has been very difficult for archaeologists to determine what, if anything, the “Fremont Complex” corresponds to in social reality. One widespread characteristic of Fremont groups, however, is evidence of contact with and influence from Anasazi groups to the south, most notably in the adoption of agriculture and pottery but to some extent in other phenomena as well.

It’s possible that whatever practices are behind the mysterious assemblages of extensively mutilated and burned human bones known from Anasazi sites such as Cowboy Wash in Colorado were among the Anasazi influences on the Fremont as well. A paper reporting on assemblages like this at Fremont sites in central Utah was published by Shannon Novak and Dana Kollmann in 2000, around the same time that the Cowboy Wash papers and Christy Turner’s Man Corn were also published and drew considerable attention to the issue of Anasazi cannibalism. That context is important for understanding Novak and Kollmann’s interpretation of the Fremont sites, which explicitly takes Turner’s interpretations as a starting point and presents the Fremont evidence as incompatible with them.

To recap, Turner argues that the cannibalism assemblages in the Anasazi are are associated specifically with the rise of Chaco as a regional system, and further that the driving force behind all of this was Toltecs from central Mexico coming up to Chaco and establishing a violent, hegemonic tributary system involving extensive warfare and cannibalism. (I should note that I have not read Man Corn myself, and this interpretation of Turner’s ideas is based primarily on summaries by other authors who are critical of them, so it’s possible that this is a misrepresentation of Turner; in any case, this is certainly what Novak and Kollmann take Turner to be saying.) This theory is problematic for a whole bunch of reasons, and Novak and Kollmann present some more.

According to Novak and Kollmann, there are three Fremont sites with evidence of cannibalism: Backhoe Village, Nawthis Village, and Snake Rock Village. They are all in close proximity to each other in central Utah (near modern Richfield), and were occupied around the cultural peak of the Fremont period, around AD 1000. This makes them roughly contemporary with the florescence of the Chaco Phenomenon to the south, although it’s important to note that Fremont chronology is mostly based on radiocarbon dates and is less precise than the tree-ring based Anasazi chronology so it’s hard to demonstrate very close correspondences between events in Fremont and Anasazi sites. This will be important in interpreting these cannibalism assemblages, as discussed below.

Although Novak and Kollmann mention three sites with evidence of cannibalism, their paper contains a detailed discussion of only one, Backhoe Village. This is the site with the largest number of cannibalized individuals, eight, compared to three from Nawthis and two from Snake Rock. Backhoe also has a fairly secure context and was carefully excavated, as opposed to Snake Rock, where looting had disturbed the remains and rendered their context unclear.

The assemblage at Backhoe was clustered in a single pithouse and was initially interpreted by the excavators as a secondary burial (otherwise unknown for the Fremont) burned at some point by the same fire that burned the roof timbers found above it. Novak and Kollmann question this interpretation and argue instead that this assemblage instead shows the same signs of cannibalism found at Anasazi sites to the south, including cutmarks and burning. Methodologically they focused on reconstructing the processing sequence applied to the remains, which is an interesting approach that I haven’t seen applied in other analyses of cannibalism assemblages (though it’s possible I just haven’t noticed it). The patterns they found, especially for skulls and long bones, were consistent with the people having been killed (in some cases with “a series of heavy blows to the face”), scalped, dismembered, and roasted. Four men, two women, and two children were represented in the assemblage. This evidence looks convincing to me, and I’m quite prepared to accept the interpretation that this is an instance of cannibalism much like those documented at Cowboy Wash and elsewhere.

Novak and Kollmann then go on to situate their results in the context of Turner’s Chaco-based theory of Anasazi cannibalism. They argue that these sites were well beyond the Anasazi culture area, which is true (there are Fremont sites in close proximity to the Anasazi frontier, but these sites are considerably further north), and that as small agricultural hamlets, they would have little to offer the Chacoan tribute system, which is more questionable. After all, many of the Anasazi communities within the Chacoan sphere of influence were also pretty small and wouldn’t necessarily have had much to offer in tribute. All these communities were growing at least some amount of corn, and at a minimum could have contributed that. The sheer distance from Chaco to central Utah is a better argument against simply extending Turner’s theory to include these assemblages, I think.

Fremont Shield-Bearing Warrior Petroglyph, Moab, Utah

Fremont Shield-Bearing Warrior Petroglyph, Moab, Utah

In contrast to Turner’s theory, Novak and Kollmann tentatively propose that this is perhaps an example of a behavior diffusing from the Anasazi to the Fremont and perhaps acquiring new meanings along the way. This would certainly not be a surprise, given all the other behaviors that appear to have undergone the same process. They note the prominence of warrior motifs in Fremont rock art as context for violence within Fremont society. Finally, they situate the evidence for violence among the Fremont within a pattern of rising violence in the Southwest in general:

Escalated violence within the American Southwest around AD 1000 is apparent, and this violence appears to have reached further north than previously identified. What we may be seeing in the Anasazi Culture Area is perhaps merely the culmination of widespread and endemic warfare. Fortification of Anasazi villages, evidence of numerous trauma deaths, and the butchering of men, women, and children imply more than simply accusations of witchcraft. Violence between neighbours can be vicious, and real and imagined atrocities often accompany this conflict.

Fair enough in terms of explaining these specific assemblages, but from a broader southwestern perspective this looks a little odd. Escalated violence around AD 1000? In most of the Southwest the period from about 1000 to 1150 is actually considered remarkably peaceful, and in the Chaco area this is sometimes explained as some sort of “Pax Chaco” in which the influence of Chaco led to a period of widespread peace. (It is hard to say which way the causation goes, however; maybe the peace was instead a necessary condition for the rise of Chaco in the first place.) Obviously this is in contrast to Turner’s interpretation of the rise of Chaco as involving widespread war and cannibalism in a Mesoamerican fashion, but that interpretation has basically no support in the archaeological record. Almost all of the well-dated and firmly established cannibalism assemblages date to AD 1150 or later, and the earlier ones are generally earlier than AD 900 and date to an earlier period of extensive evidence for warfare and violence.

So what’s going on here? One possibility is that we’re seeing the consequences of the mismatch in chronological precision I mentioned above. “Around AD 1000″ may mean very different things at Fremont and Anasazi sites. At the Fremont sites, dated primarily by radiocarbon, this could refer to a period of a couple hundred years, in which case it might extend as late as the post-Chaco period of cannibalism and violence (0r as early as the pre-Chaco one). At Anasazi sites, on the other hand, with their very precise tree-ring dates, “around AD 1000″ would generally mean very close to the actual calendar date of AD 1000, maybe within twenty or twenty-five years. This is a considerable difference in precision! It’s also noteworthy that “around AD 1000″ is also more or less the conventional date for the “peak” of Fremont settlement and cultural development from roughly 1000 to 1300, so its being applied here could just mean that these sites date to that period, within which the level of violence rose throughout the Southwest (which is certainly true).

Linear Roomblock at Coombs Village (Anasazi State Park), Boulder, Utah

Linear Roomblock at Coombs Village (Anasazi State Park), Boulder, Utah

That said, however, there does actually appear to be a fair amount of evidence that there was in fact a considerably higher level of violence in the Fremont region than elsewhere in the Southwest even in the “Pax Chaco” era. A general summary of Fremont archaeology by David Madsen and Steven Simms discusses some of this evidence. Madsen and Simms describe the period of 1000 to 1300 as one of “demographic fluidity” involving the apparent abandonment of certain parts of the Fremont region and intensified settlement with defensive features in others. This appears to have begun at least in some areas as early as AD 900 and is most noteworthy in the eastern Fremont area on the northern Colorado Plateau, where there also seems to have been a breakdown in the traditional boundary between Fremont and Anasazi along the Colorado River and the expansion of sites with Anasazi features north of the river. It is not clear to what extent this reflects a migration of Anasazi people as opposed to increased Anasazi influence on local Fremont people, but it’s clear that something was going on along the Anasazi-Fremont boundary during the height of the Chacoan era. It’s noteworthy that one site Madsen and Simms mention as having granaries built in a characteristically Anasazi form is Snake Rock, one of the same sites that has a cannibalism assemblage. The puzzling Coombs Village site (now Anasazi State Park in Boulder, Utah), which is clearly Kayenta Anasazi in culture but located very far north in traditionally Fremont country, also dates to around this time. In fact, as Joel Janetski notes in a paper on Fremont long-distance trade, there is some evidence of pottery exchange between Coombs and Snake Rock, about 50 miles to the north.

The upshot of all this is that there was clearly extensive contact between the Anasazi and the Fremont during the Chacoan era, and there is some evidence that it was not nearly as peaceful in this area as it was in the Anasazi heartland at the same time. The much “blurrier” chronology of the Fremont sites makes it frustratingly difficult to pin down exactly what was going on in Utah at the same time as the various important events in the history of Chaco, but these indications that Utah was “out-of-phase” with areas to the south in some ways is, I think, potentially significant for understanding the history of both.

It’s also worth noting that while the actual Anasazi interacting with the Fremont were from the Kayenta and Mesa Verde cultural “branches” rather than the Chacoan, there is reason to think that at least some people at Chaco would have had a keen interest in events in Utah. For one thing, the Janetski paper on Fremont trade notes that while long-distance trade goods like turquoise and shell are much rarer in Fremont than in Anasazi sites, they are present among the Fremont to some extent, and there is some evidence that the turquoise found at some Fremont sites came from the same sources as that at some Anasazi sites, including Chaco. Janetski interpreted this as indicating that the Fremont turquoise came from the Anasazi, which is certain one reasonable interpretation, but he also mentions evidence that some of the Fremont turquoise came from sources in Nevada, which more recent sourcing has confirmed for some of the Chacoan turquoise as well. Maybe, instead of getting turquoise from the Anasazi, the Fremont were giving it to them as part of a wide-ranging trade network. This might even explain why so little turquoise is found at Fremont sites, if they didn’t actually have much interest in it but used it to trade for Anasazi goods that they did want. Interestingly, Janetski also notes that most of the turquoise in Fremont sites appears to date to after the period of its most common appearance in Anasazi sites from 900 to 1100 (which is driven mostly by the vast amounts found at Chaco), which could be explained if the Fremont, having relatively easy access to turquoise from trading partners in the Great Basin, began holding on to it once Anasazi demand weakened with the decline of Chaco.

Edge of the Cedars Great House, Utah

Edge of the Cedars Great House, Blanding, Utah

Much of that is speculative, but if the Great Basin was in fact one of Chaco’s main sources for turquoise, and if some of the trade routes for that turquoise went through the Fremont, Chaco would have a clear interest in the Fremont area. It would certainly have had contact with some Anasazi groups near the Fremont frontier, as there are communities showing Chacoan influence in Utah north of the San Juan River (though not as far north as the Colorado, as far as we know), with Edge of the Cedars in modern Blanding being a clear example. This area would presumably have been the source of whatever migration or influence extended north of the Colorado in this area after AD 1000, so a Chacoan connection is not as implausible as it might seem at first glance. Further west Chacoan influence is harder to see among the Kayenta Anasazi, but some level of contact is at least possible.

It’s not clear what implications this possibility of Chacoan involvement in Utah would have for the cannibalism assemblages Novak and Kollmann discuss, however. For one thing, I think Turner is just wrong that cannibalism in the Southwest is associated with the rise of Chaco; it seems to correlate more closely with its fall. Also, the specific sites in question seem to be beyond the reach of any plausible Chacoan direct influence, although at least one clearly had some contact with the Kayenta Anasazi at Coombs. They could also have been involved in the turquoise trade, of course, and according to Janetski small amounts of turquoise were found at Snake Rock and Backhoe. The lack of any known cannibalism sites between these and the better-known Anasazi examples also limits the extent to which we can figure out what was going on. Interestingly, Novak and Kollmann note that one other site, Turner-Look, which is near the Colorado-Utah border and hence much further east than the other sites and much closer to the Anasazi cannibalism assemblages, has been suspected in the past of having evidence for cannibalism, but they say a recent reanalysis has found no such evidence, although there is some evidence for violence. If more Fremont sites with assemblages like this begin to emerge, especially further east, it might be possible to get a better sense of how this all fits together.
Janetski, J. (2002). Trade in Fremont society: contexts and contrasts Journal of Anthropological Archaeology, 21 (3), 344-370 DOI: 10.1016/S0278-4165(02)00003-X

Novak, S. A., & Kollmann, D. D. (2000). Perimortem Processing Of Human Remains Among The Great Basin
Fremont International Journal of Osteoarchaeology, 10, 65-75


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