The Ancient Texas Coast

Trail in Brazos Bend State Park, Texas

The big story in the news these days is of course Hurricane Harvey, which has been battering the Gulf coast and adjacent areas of Texas and Louisiana for days now. While it has so far probably done the most damage in Houston, with record rainfall leading to massive flooding in one of the country’s biggest cities, Harvey first came ashore further south, near the small town of Rockport, Texas just north of Corpus Christi. Rockport was very severely damaged by the wind and rain, of course, and has gotten quite a bit of media attention for that.

Rockport has another claim to fame, however, at least for those of us interested in archaeology and prehistory: it is the namesake of the Rockport Phase, an archaeological complex that existed on the central part of the Texas coast in the late prehistoric period and is generally thought to be directly ancestral to the Karankawa people who occupied the same area at European contact. The Karankawa are among the better-documented of the many cultural groups that occupied the Gulf Coast, partly because of the detailed account of them left by Álvar Núñez Cabeza de Vaca, who was shipwrecked in this area in 1528 and spent several years living with the natives here and further west as he made his way back to his Spanish compatriots in Mexico. Archaeological research over the past few decades has both confirmed some aspects of this and other historic accounts and added additional information about the culture history of this area.

The Rockport Phase is characterized by a distinctive type of pottery, gray in color with thin, hard walls and a sandy paste. It can be plain (i.e., undecorated), incised, or, most distinctively, decorated with the black asphaltum found in the Gulf area and associated with its extensive petroleum deposits. The beginning date for the Rockport Phase varies in the literature but is in the range of AD 1000 to 1250; the variation is probably due to the fact that Rockport is clearly continuous with the previous Late Archaic culture of the same area. In general, however, the Late Prehistoric period on the coast is defined by the appearance of the bow and arrow and pottery, both of which seem to have reached the central coast around AD 1000 from the north. (Note that this makes at least the beginning of Rockport roughly contemporary with Chaco Canyon far to the west.) As noted above, Rockport is also clearly continuous with the historic Karankawa, and Rockport pottery has been found on some early historic sites.

While pottery is often associated with agricultural people, agriculture was never practiced on the prehistoric Texas coast or, indeed, most of the interior areas of prehistoric Texas. The Rockport people, like their neighbors in all directions, were hunter-gatherers, and they appear to have had a subsistence system based primarily on the rich aquatic resources of the coastal estuaries but with seasonal movements inland to hunt terrestrial game and gather plant resources including pecans and the fruit of the prickly pear cactus.

Warning Sign, Brazos Bend State Park, Texas

The stone tool assemblage of the Rockport Phase, at least from around AD 1250 on, was very similar to that of the inland groups in central and southern Texas, all of which were part of the Toyah Horizon distinguished by the use of Perdiz arrow points. This widespread lithic complex is generally thought to be associated with the hunting of bison, which appear to have rapidly spread south from the southern Great Plains into central and southern Texas during the thirteenth century AD, possibly in response to a drying trend beginning a couple centuries earlier that expanded the grasslands favored by bison. Despite Rockport use of this lithic complex and the presence of bison bone in some Rockport sites, however, stable isotope studies of human remains from cemetery sites on the coast that are contemporary with Rockport have not shown evidence that bison was a substantial part of the diet, which seems to have been heavily based on fish and other marine resources. More research may clarify this apparent clash of different types of evidence.

Speaking of those cemeteries, they area also unusual among hunter-gatherers but quite common in prehistoric Texas, in both coastal and interior areas. Cross-culturally, use of cemeteries rather than isolated burials by hunter-gatherers tends to be associated with “packing” into small territories due to high population densities, as well as with “intensification” of production of subsistence resources, especially aquatic ones. Some archaeologists have proposed theories linking intensification, which includes but is not limited to the development of agriculture, to increased population density due to highly productive resources in certain areas, which also leads to packing into smaller territories. Some of these theories further predict that this will mean less use of terrestrial hunting and increased use of aquatic resources where they are available, and plant resources where they are not.

This type of theory has been tested in Texas and found to largely but not completely explain the distribution of cemeteries and other signs of packing and intensification. In the Rockport area, which clearly had a relatively high population density and depended heavily on the aquatic resources of the estuaries, the theory seems to work. It also works for the Rio Grande Delta area to the south, where the populous Brownsville Complex had its own type of pottery as well as various cultural influences from and trade ties to the Huasteca region of northeastern Mexico to the south. It doesn’t really account for the presence of cemeteries and other signs of intensification in the more sparsely populated areas of central and western Texas, however, where hunter-gatherer populations are thought to have been much lower. Clearly more research on this issue is required. Many of these characteristics are associated with “complex” hunter-gatherers such as those of the Northwest Coast, but I doubt any anthropologist would describe even the higher-density groups on the Texas coast as complex in that sense.

It doesn’t get as much attention as some other areas, and it certainly isn’t as flashy as the ruins in the Four Corners region, but the archaeology of Texas is actually quite interesting. The University of Texas has a great website called Texas Beyond History that provides a lot of information in an easily accessible. It wasn’t a major source for this post, but it’s still definitely worth checking out. We’ve been seeing a lot about Texas in the news lately, but there’s much more to it if you dig a little deeper.

Texas Flag and Sundial, Brazos Bend State Park

Advertisement

Read Full Post »

Foreshadow: Animal Bones

McPhee Reservoir, Dolores, Colorado

The first of the shorter, more analytical chapters in Crucible of Pueblos that follow the regional summaries is one by James Potter looking at faunal remains, which in this context basically means animal bones. (I guess this is sort of appropriate for a Halloween post, although animal bones aren’t really as spooky as human ones.) This chapter is basically a series of statistical comparisons of faunal assemblages from different Pueblo I sites, focusing particularly on the large, well-document collections from the Dolores and Animas-La Plata Projects, but also including a few others. Given the focus on these collections, the geographical range of these comparisons is limited to the Central and Eastern Mesa Verde regions. Nevertheless, Potter finds some striking differences between different sites that have interesting implications for understanding their inhabitants’ lives.

The first comparisons are of different villages within the Dolores area. Potter uses two widely used calculations, known as the artiodactyl index and lagomorph index, to compare McPhee Village on the west side of the Dolores River to Grass Mesa Village on the east side. The artiodactyl index is a measure of how common large game animals, such as deer and elk, are within the overall assemblage, and is calculated by taking the number of artiodactyl specimens in the assemblage and dividing it by the number of artiodactyl specimens plus lagomorph (rabbit and hare) specimens. The lagomorph index compares the number of specimens of the two most common lagomorph species, cottontail rabbits and jackrabbits, and is calculated as the number of cottontail specimens divided by the combined number of cottontail and jackrabbit specimens. This is an important measure because cottontails and jackrabbits favor different habitats and have different behavior which can shed light on human land use and hunting practices: jackrabbits prefer open spaces such as those created by clearing land for agriculture, and as a result can often be caught within gardens, while cottontails prefer more sheltered brushy environments. Jackrabbits also run to escape predation while cottontails hide, which makes the former more vulnerable to the kind of communal hunting known to have been practiced by Pueblo peoples in more recent times.

In the case of McPhee and Grass Mesa Villages both indices show little to no difference between the two; indeed they are nearly identical. This suggests that there weren’t major differences between the two communities in land clearing, communal hunting of lagomorphs, or hunting of artiodactyls. This is maybe not surprising, as the two villages are only a few miles apart and in similar ecological settings.

Where they do differ, however, is in another comparison, in this case of the prevalence and diversity of bird remains. McPhee Village has many more bird remains, representing more than twice as many species, than Grass Mesa, despite the overall sample sizes being similar. Furthermore, the avian bones are concentrated within McPhee Village at one particular residential site, known as McPhee Pueblo. This is one of the largest residences in the community and has features that have been interpret as reflecting ritual activity at a level higher than the individual residential group inhabiting the site. This site is considered likely to be a prototype of the “great houses” associated with the later cultural phenomenon centered on Chaco Canyon, where many of the inhabitants of the Dolores area are thought to have gone after the demise of the Pueblo I villages there in the late ninth century AD. The greater number of bird species, and the large number of specimens, at McPhee Pueblo reinforces other indications of the special role this site played in the community. Birds have often been associated with ritual among the Pueblos, with the macaws at Chaco being only one of the most spectacular examples. The fact that there is no similar site at Grass Mesa, and that bird remains are much rarer there overall, suggests significant differences in ritual organization at the two villages despite their proximity, which fits with other evidence suggesting they were settled by people from different cultural backgrounds.

The second major set of comparisons Potter makes addresses change over time, again within the Dolores area. He compares the artiodactyl and lagomorph indices of McPhee Village and the nearby but earlier community of dispersed hamlets known as Sagehen Flats. In this case, the Sagehen Flats sites had much lower artiodactyl indices, which suggests to Potter that this community had more difficultly organizing hunting parties to capture these large animals than the later, larger, and more aggregated community at McPhee. Indeed, it has been suggested that one reason for the formation of the large Pueblo I villages was the opportunity that larger communities provided for more effective hunting of large animals, especially in high-elevation areas close to large populations of artiodactyls.

Sagehen Flats also had a higher lagomorph index value, indicating more cottontails relative to jackrabbits, and suggesting that aggregation at McPhee also included more clearing of land for agriculture, creating the open spaces preferred by jackrabbits. It is also likely that larger communities were more effective at communal hunting, which as noted above would have been easier with jackrabbits. It’s not really surprising that larger communities would have cleared more land for agriculture and conducting larger communal hunts, but this evidence does provide another reason to think that.

Bird remains, on the other hand, were present in very similar proportions at both Sagehen Flats and McPhee, with both much higher than Grass Mesa. This likely results in part from the location of Sagehen Flats near marshes with lots of good habitat for waterfowl, but it’s also noteworthy that the bird remains there, as at McPhee, were heavily concentrated in one habitation site. This site, unlike McPhee Pueblo, doesn’t show other signs of having been exceptionally important compared to others, but it is highly intriguing that there were so many birds there, and it suggests that the pattern of unequal ritual influence seen at McPhee, and later at Chaco, goes back even further, at least in this area.

Durango, Colorado

Next, Potter does a broad comparison of several different site areas, this time treating the Dolores sites as a whole and comparing them to the nearby hamlet of Duckfoot as well as the site clusters of Ridges Basin and Blue Mesa to the east near the modern city of Durango, as well as sites in the Fruitland area to the south near the modern Navajo Reservoir. Starting with the artiodactyl and lagomorph indices, Potter finds high artiodactyl index values at Dolores and Ridges Basin, with much lower ones at Duckfoot and Fruitland. The factors mentioned earlier leading to more effective artiodactyl hunting in larger villages are probably one factor here, with another being elevation, with the higher sites having more artiodactyls than lower ones.

The lagomorph index is highest at Duckfoot and Blue Mesa and lower at Dolores and Ridges Basin, again echoing the pattern seen before where larger villages show evidence for more land clearing and communal hunting compared to smaller, more dispersed sites.

Turning to birds, Potter finds the highest numbers in Ridges Basin, with significantly smaller numbers at Dolores and Duckfoot. (Keep in mind that all of the Dolores sites are lumped together here.) This is likely due in part to the marshy environment of parts of Ridges Basin, but it is also due to much more extensive use of turkeys in Ridges Basin than elsewhere.

Following these rather simple comparisons, Potter does a correspondence analysis of all of the areas comparing categories of animal remains: birds, wild carnivorous mammals, domesticated dogs, lagomorphs, and artiodactyls. This analysis shows that the areas have very distinct associations with particular types of animals. Blue Mesa, Fruitland, and Duckfoot are associated with lagomorphs, Dolores with artiodactyls, and Ridges Basin with both birds and dogs. Potter notes that while Dolores and Ridges Basin have very similar artiodactyl indices, as this analysis suggests, they have very different overall percentages of artiodactyls. The index is thrown off because it uses lagomorph numbers to standardize the artiodactyl numbers, which is problematic in cases like this because the number of lagomorphs also differs a lot between the two areas, with a lot fewer of them at Ridges Basin than at Dolores.

Next, Potter does a detailed analysis of the Ridges Basin community, comparing categories of remains among different site clusters within the basin. He uses a more detailed set of a categories here than in the previous analysis: mammalian carnivores, birds of prey, waterfowl, dogs, turkeys, game birds, artiodactyls, and lagomorphs. The different site clusters show interesting differences in the proportions of these, with the marshy eastern cluster having higher numbers of waterfowl and turkeys. As mentioned above, turkeys are more common throughout Ridges Basin than in other Pueblo I communities, but there are differences in both numbers and context within the basin. The turkeys in the eastern sites are mostly burials, part of a widespread Pueblo practice of burying domestic animals that likely has ritual significance. In some site clusters, however, there is evidence for processing of turkey remains suggested they were used as food. In the north-central cluster there is one pit structure that seems to have been used as a processing area for turkeys and rabbits, and the same site also had turkey eggshells, suggesting strongly that these were domesticated rather than wild turkeys.

Dogs, wild birds, and carnivorous mammals are found mostly as burials throughout Ridges Basin, with some accompanying human burials. This is in contrast to McPhee Pueblo, which as mentioned above had high numbers of wild birds, where remains of ritually important animals like these were found in association with ritual structures. There is no such association anywhere in Ridges Basin, suggesting that while these animals were likely ritually important in both areas, the exact nature of the associated ritual differed.

As for artiodactyls, here as elsewhere they were found in greater numbers at the only aggregated site cluster that can be considered a village: Sacred Ridge. Since this site also has higher numbers of projectile points and processing tools, Potter suggests that the artiodactyls were the result of more effective hunting parties drawn from the larger village population, rather than evidence for special status of the residents of Sacred Ridge or special feasting being conducted there. There are a lot of unusual features to this site, however, so it’s hard to know how to interpret it.

That concludes Potter’s analyses. He ends the chapter with some conclusions that they suggest. First, as seen in multiple analyses, large sites tend to have more artiodactyls than small ones, probably because larger, more aggregated settlements allowed for the building of cooperative hunting parties that were more effective at taking down large game. This was a definite material advantage to community aggregation and the formation of villages, a key characteristic of the Pueblo I period that has led to a lot of questions about why and how it happened. It’s noteworthy, however (although Potter doesn’t note it) that the Pueblo I villages were as a rule short-lived and many seem to have been abandoned under duress, so the greater cohesiveness that allowed for these more effective hunting parties seems to have had definite limits under the circumstances.

Another pattern that emerges is the association of some sites with marshes and the extensive use of waterfowl, and presumably other marsh resources, at these sites. Potter connects this with the general importance of marshes, lakes, and other water places in Pueblo religion and ritual, as well as with the later artificial reservoirs built in the Mesa Verde region. It’s possible that an initial tendency to settle near wetlands because of their practical advantages in terms of resources led over time to a more metaphysical attitude toward watery places, although this remains highly speculative.

There is also a tendency over time for a shift in the contexts in which remains of animals of presumed ritual significance, like wild birds and carnivorous mammals, with early sites such as those in Ridges Basin having them largely associated with burials and the ceremonial “closing” of residential sites, whereas at later sites such as those in the Dolores area they are more associated with communal ritual structures. This suggests a shift in use of these religious symbols from the private to the public sphere, which Potter notes has also been proposed over the same period for the use of red ware pottery, which also likely had ritual significance. This shift may have continued into the rise of the Chacoan system, with its increased focus on monumental architecture presumably associated with public ritual.

Finally, Potter notes the early importance of turkeys in Ridges Basin, which could be due to general environmental differences across the region but may also reflect earlier depletion of large game in this area compared to others. There is a general pattern through Pueblo prehistory of increasing use of turkeys for meat as artiodactyl use declines, presumably in response to overhunting of local populations. On the other hand, one intriguing thing about the greater use of domesticated turkeys at the eastern edge of the Mesa Verde region during Pueblo I is the genetic evidence showing that domestic turkeys in the Southwest are likely more closely related to wild subspecies found to the east than to those found locally. Could the use of turkeys in Ridges Basin reflect early contacts with peoples further east? Potter doesn’t mention this possibility, and I don’t know if there is any other evidence of such contacts, but again, intriguing.

So, yeah, this chapter is a lot more focused than those coming before it, but the results of its analyses are intriguing. As more evidence becomes available from other regions with Pueblo I populations it may be possible to extend these sorts of comparisons further.

Bone Tools at Chaco Museum

Read Full Post »

Foreshadow: The Rio Grande

Rio Grande from Coronado State Monument, Bernalillo, New Mexico

Chapter seven of Crucible of Pueblos brings us to the final geographical region covered by the volume: the Rio Grande Valley, at the eastern edge of Pueblo settlement for the period in question. As it happens, I’m currently visiting my mom in Albuquerque, so I’m actually in this region as I write this. (Today also happens to be my birthday; I’m 31.) The chapter is by Steven Lakatos and C. Dean Wilson, and in a lot of ways it echoes an earlier paper by Lakatos about the Rio Grande Developmental Period that I have discussed before. This chapter, however, discusses only the Early Developmental Period, defined as AD 600 to 900, and primarily focuses on the part of the region that the authors called the Middle Rio Grande Valley, defined as lying between the Rio Puerco of the East on the west, the Sandia and Manzano Mountains on the east, the Isleta area on the south, and the La Bajada escarpment on the north. This is because agricultural populations only occupied this restricted area of the region during the Early Developmental, expanding north of La Bajada only after AD 900 when there was a huge increase in regional population at the beginning of the Late Developmental Period.

The key point Lakatos and Wilson make about the Rio Grande is that the Early Developmental period was a time of low population density and gradual growth, with little change in material culture over hundreds of years. This is in striking contrast to the “boom-and-bust” pattern now richly documented for the Mesa Verde region during the contemporaneous Pueblo I period there. The picture of continuity is reminiscent of that proposed by the authors of the previous chapter for the Little Colorado region, but it’s worth noting that the major data gaps that plague the study of that region are less of an issue for the Rio Grande, which has a long history of intensive archaeological research continuing to the present day. Furthermore, Lakatos and Wilson present several lines of evidence supporting their conclusions, which seem pretty solid to me. Based on this evidence, it really does seem like the Early Developmental was a time of low population, slow growth, and cultural continuity.

As Lakatos and Wilson note, this is actually a rather surprising conclusion in the context of many theories about early agricultural societies. Most strikingly, there is no evidence here for a “Neolithic Demographic Transition,” in which the increased productivity of agricultural societies compared to hunter-gatherers leads to massive growth among early agriculturalists, with all sorts of ecological and social consequences. Some have argued that the Mesa Verde boom-and-bust cycle is a result of this process. In the Rio Grande, however, the adoption of agriculture does not seem to have resulted in this sort of population growth. This is definitely not for lack of arable land, as the Rio Grande Valley is one of the richest agricultural areas in the northern Southwest, and it was intensively farmed later in prehistory and into historic times. Rather, Lakatos and Wilson argue that the richness of the Rio Grande environment allowed for a mixed farming-foraging economic pattern with high residential mobility, in contrast to the more agriculture-dependent societies further west. The greater importance of foraging versus farming is supported by evidence from faunal assemblages and wear patterns on human remains, and the mobility by the fact that residential pit structures were rarely remodeled.

In keeping with low density and high mobility, the settlement pattern consisted of scattered hamlets, with only occasional evidence for “communities” of hamlets loosely grouped together with possible communal architecture such as “protokivas” or oversized pit structures. Sites were mainly located along the major rivers of the region: the Rio Grande itself, the Rio Puerco of the East, the Jemez. Architecture consisted of residential pit structures and surrounding activity areas, generally oriented toward the east or southeast (perhaps oriented to the winter solstice).

Rio Grande people also appear to have been in closer contact with remaining hunter-gatherers than populations further west. It’s not clear if Early Developmental populations resulted from the adoption of agriculture by existing hunter-gatherers in the Middle Rio Grande Valley or if there was some migration of already agricultural populations involved, but in any case the areas north of La Bajada and east of the Sandias/Manzanos were definitely still occupied by hunter-gatherers during this period, and it’s clear that there was a lot of contact between the two groups. This may have contributed to the greater importance of foraging to Early Developmental people and their differences from other Pueblo populations.

Sandia Mountains from Tent Rocks National Monument

All that said, the Early Developmental people definitely were part of the Pueblo cultural tradition, and their material culture shows a lot of connections to populations to both the west and south. This is particularly true of pottery, which was dominated by plain gray ware similar to that of late Basketmaker groups on the Colorado Plateau, but with small amounts of a decorated white ware, San Marcial Black-on-white, which shows stylistic influence from Mogollon populations to the south but with technological characteristics more like those of early white wares to the west. Lakatos and Wilson mention one model of Southwestern prehistory under which early “strong patterns” of material culture originated in the San Juan Basin (ancestral to the Chaco system) and in the river valleys of the Mogollon region, with the Middle Rio Grande forming a “weak pattern” with influences from both but in varying combinations.

The clear picture that emerges from this is of a small population of forager-farmers moving around within the Middle Rio Grande area but maintaining their basic cultural features with little to no change for about 300 years, from AD 600 to 900. Then, in a development that is likely very important but poorly understood, there was a massive increase in population at the same time that agricultural groups for the first time began to occupy the higher areas about La Bajada. Lakatos and Wilson note that the timing of this change, while not as precise as might be ideal, seems to correspond closely to the collapse of the late Pueblo I villages in the Mesa Verde region and the major population movements involved with the depopulation of that area, including the apparent influx of people into the Chaco Basin that likely laid the groundwork for the Chaco Phenomenon.

It seems very plausible that the increase in population in the Rio Grande was linked to these developments, though exactly how is unclear. Material culture actually remained fairly stable and consistent with Early Developmental patterns across this transition, although architecture did become more standardized and San Marcial Black-on-white was replaced by Red Mesa Black-on-white as the main decorated ceramic type. The latter change, especially, suggests influence from the west, as Red Mesa is the main decorated type in the Chaco area and other parts of the southern Colorado Plateau during this same period. It’s possible, as Lakatos and Wilson suggest, that the increased population in the Chaco Basin directly spurred Middle Rio Grande populations to move northward, although it’s not clear how exactly this would have worked. Other possibilities are that populations from the intermediate areas, such as the Puerco of the East, began to move eastward in the Rio Grande Valley as a result of the population movements immediately to the west of them, perhaps pushing existing Rio Grande populations north, or that western populations were moving directly to the Northern Rio Grande area above La Bajada, “leap-frogging” existing populations in the Middle Rio Grande.

The fact that material culture continued to show local Rio Grande features throughout the region, however, suggests that some level of assimilation or cultural accommodation between the locals and immigrants was involved, rather than a more directly confrontational situation. It’s noteworthy that Lakatos and Wilson don’t discuss evidence for warfare or defensive features at all, which of course doesn’t mean those things didn’t exist but does suggest that they may have been less prevalent than in some other regions.

Turquoise-Encrusted Cow Skull, Santa Fe, New Mexico

Another thing Lakatos and Wilson don’t discuss, but which seems particularly important to understanding these relationships, is turquoise, specifically that from the well-known mines in the Cerrillos Hills east of the Sandias. Turquoise is of course strongly associated with Chaco, and while not all of the turquoise there has turned out to be from Cerrillos, a substantial portion of it definitely was. Evidence for increased connections between the San Juan Basin and the Rio Grande area at the same time as the rise of Chaco as a regional center is very intriguing in this light. Could increasing demand for turquoise at Chaco have led to the Cerrillos mines being a “pull” factor leading western groups into the Rio Grande Valley? Could the mines have even led local Rio Grande groups, or mixed groups of locals and immigrants, to move further east, across the mountains and even up over La Bajada into the Santa Fe area, which may have become more attractive as increased immigration reduced the supply of land in the Middle Rio Grande? And what about those remnant hunter-gatherer groups east of the Sandias and north of La Bajada? What happened to them? Were they attacked and defeated by the encroaching farmers? Pushed out into areas further north and east? Assimilated into agricultural society, which even in the Late Developmental period had a strong foraging component? There are a lot of questions about this period in this area, and very little evidence on which to base any answers. Lakatos and Wilson recognize this and suggest some research directions that would be helpful in answering the remaining questions, although they don’t point out as many as I have here.

Overall, this is a very informative chapter that brings into the discussion of Pueblo I societies an area that is often left out of these discussions. It’s an area of crucial importance for understanding regional dynamics throughout the northern Southwest, however, so I’m glad it was included in this volume. This chapter concludes the geographical summaries in the book; the remaining chapters cover various thematic topics of interest in understanding the Early Pueblo period as a whole.

Read Full Post »

What Happened to the Fremont?

Paiute Brush Shelters, Pipe Spring National Monument

As I mentioned in the previous post, the most mysterious thing about the Fremont is what happened to them. Unlike the Anasazi, who obviously became the modern Pueblos, the Fremont have no obvious connections to any modern groups. Fremont sites appear to disappear around AD 1300 in most areas, although there is some regional variation and in part defining an end date depends on how you define “Fremont.” Since the practice of agriculture is closely associated with the Fremont complex, the latest dates of sites with clear evidence for agriculture is one convenient way to date the end of the Fremont. In their important 1998 review essay, David Madsen and Steven Simms give the following dates for the end of agriculture in different Fremont regions:

• Uinta Basin: AD 1000
• Parowan Valley and Great Salt Lake wetlands: AD 1100 to 1150
• “Much of the Fremont region”: AD 1250 to 1300
• Northwestern Colorado: After AD 1450

(Note that Madsen and Simms annoyingly cite their dates as “Before Present” without specifying what date they are using for the “Present” or whether these are calendar or radiocarbon years; in calculating the above dates I have assumed a “Present” of AD 1950 as conventionally used in radiocarbon determinations.)

The Madsen and Simms date for much of the region is very close to the “Great Drought” of AD 1276 to 1299 known from Anasazi sites to the south (assuming of course that their dates are in calendar years). Given the low precision of the radiocarbon-based Fremont chronology compared to the tree-ring based Anasazi one, however, it is risky to make too much of coincidences like this, and the wide variation across different Fremont sub-regions suggests that something more complicated is going on here than a simple reaction to a single prolonged drought. The Great Drought may well have affected Fremont farmers, of course, but the Fremont data are not clear enough to establish a definitive association. In general a rough date of AD 1300 for the end of Fremont in most areas is widely used and probably close enough for most purposes. It does seem that some form of the Fremont lifestyle persisted significantly longer in northwestern Colorado, which could have served as a refuge for Fremont farmers displaced from other areas.

In keeping with their general interpretation of Fremont as involving a wide variety of adaptive strategies and frequent movements of people between farming and foraging, Madsen and Simms interpret the end of the phenomenon as consisting largely of farmers switching to foraging, along with possible immigration of foragers from outside the region. Basically they see this period as a time when the precarious balance between farming and foraging characteristic of the Fremont period tipped decisively in favor of foraging, perhaps in response to climatic changes that made foraging a more effective subsistence strategy.

Whatever the mechanism for the collapse of Fremont as an archaeological complex, the question of what became of the people remains. There are three main logical options:

1. They died out entirely and left no descendants.
2. They changed their culture and stayed in the same region.
3. They left the region.

The first option is apparently attractive to a lot of people, judging by the popularity of descriptions of ancient peoples as “vanished” and so forth, but it’s actually quite rare for a group to literally die out entirely. It’s certainly possible that this is what happened to the Fremont, especially given the lack of continuity with later groups, but the number of people and large area involved make it implausible. That leaves us with either continuity between the Fremont and the ethnographic inhabitants of their region or a migration of the Fremont to somewhere else.

The idea that the Fremont might have developed into the hunter-gatherers known ethnographically in the eastern Great Basin and northern Colorado Plateau has a respectable history in the literature; as I noted in the previous post, James Gunnerson proposed just this back in the 1960s. The distinction in material culture between the Fremont and the Numic-speaking groups that followed them (Shoshone and Ute) is quite marked, however, as Albert Schroeder pointed out at the time. Furthermore, Madsen noted in 1975 that the distinctive Numic pottery is associated with the very different Fremont pottery at several well-dated sites in the region, suggesting that the two groups were distinct but contemporaneous. It is certainly possible that some of the Fremont assimilated into Numic society in some areas, or that the two merged in various combinations, and Madsen and Simms suggest that some such merging may have occurred in the Great Salt Lake area, though it’s not clear from their discussion whether they see the immigrant groups that merged with the Fremont as specifically Numic, as they propose a hiatus between this merged society and the ethnographically known culture of the region, perhaps due to the spread of European disease in the contact era. The whole issue of the Numic groups and how they got to where they are today is important in understanding the prehistory of these areas, but it is a big, complicated issue and I’ll address it more fully in a subsequent post. The material culture differences are significant enough that it seems unlikely that assimilation in place is the answer to the question of what happened to the Fremont in general.

As an alternative to seeing the Fremont as turning into the modern Numic groups that occupy the same areas, they may have migrated elsewhere. But where? Another theory noted in my previous post is that proposed by Melvin Aikens in the 1960s that the Fremont originally came from the Plains and ultimately migrated back there to become one or more of the ethnographically known Plains groups, probably Athabascan-speaking (i.e., Apache and/or Navajo). He based this theory on some suggestive parallels in material culture between the Fremont and Plains groups, especially the later Dismal River culture, generally thought to be associated with the Athabascan Na’isha. There certainly do seem to be some Plains-like traits in Fremont culture, including an emphasis on bison hunting, use of the shield-bearing warrior rock art motif, wearing of moccasins rather than sandals, etc. It’s not clear, however, whether these result from actual migrations of people from the Plains to the Fremont area or vice versa (and the two migrations Aikens posits would not be necessary in any case to explain the similarities). Aikens also used some physical anthropological evidence from skull morphology to support his theory, but the usefulness of the type of data he used was disputed even at the time, and it is not taken seriously at all now. Furthermore, more recent physical anthropological research using DNA analysis suggests strongly that there is no genetic connection between the Fremont and modern Athabascans or other Plains groups. In a sample of remains from the Great Salt Lake area the most common mitochondrial haplotype among Athabascans was not present at all, which is quite striking since it is quite common among Native American groups in general. It is of course possible, even likely, that this sample was not representative of Fremont groups in general, but of all the Fremont sub-areas the Great Salt Lake is the closest to the Plains both geographically and culturally, so if there’s no evidence of a genetic connection to the Plains from there it’s very unlikely that one will be found anywhere else. The same study found no clear evidence for a connection to the modern Numic groups either. This DNA stuff is another interesting, complicated issue that deserves its own post, but for now the upshot of this is that the Plains traits seen among the Fremont probably result from contact and cultural diffusion rather than migration in either direction, and the fate of the Fremont remains mysterious.

So if they didn’t go east onto the Plains, where did the Fremont go? The next obvious option is that they went south and joined the Pueblo groups with which they had many cultural similarities. This is another idea that has been proposed by some archaeologists, and it also appears to have support from oral traditions. David Pendergast and Clement Meighan published a paper in 1959 reporting that during their excavations of a site in southwestern Utah that would today be considered Parowan Fremont (though Pendergast and Meighan called them “Puebloid”) local Paiutes (a Numic group) told them some things about the people who had inhabited the site that they considered surprisingly accurate given the archaeological evidence. The Paiutes referred to the Fremont by the term Mukwitch, which is also the Paiute term for the Hopis, and reported that they had moved south and joined the Hopis when they left Utah. While their comments on the lifestyle of the Mukwitch and the reasons they had left were rather inconsistent, the consistency of the accounts of where they went is striking. The Paiutes also said that the Mukwitch were quite different from the Paiutes but had lived peacefully alongside them, which is noteworthy in light of the Numic pottery found in association with Fremont pottery mentioned above.

This paper has not been taken very seriously by archaeologists, and in fact I have not seen it cited at all in other Fremont literature. The only mentions of it I have seen, in fact, have been in cautions about the problems with taking oral traditions seriously, presumably because of the inconsistencies in the accounts. The accounts certainly are inconsistent on certain points, but consistent on others, and I think this paper deserves more attention from archaeologists wondering what happened to the Fremont. It’s certainly plausible that they moved south to join the Anasazi, and the Hopi are the most likely of the modern Pueblos for them to have ended up at for straightforward geographical reasons. A look at some of the recorded Hopi clan traditions with this in mind would likely be interesting. It’s unlikely that all of the Fremont moved south to join the Hopis, but it’s plausible that at least some did. Others may have stayed in place and been assimilated into the Numic groups spreading across the region, and still others might have died out entirely due to drought, warfare, or other factors.

So in some sense we’re back where we started, with no clear answer. But in other senses we do have some answers, at least in ruling out some options: The Fremont don’t seem to have either come from or gone to the Plains, and the Apaches are probably not their descendants. Wherever they did go (or stay), they changed their material culture rapidly and completely to assimilate into other groups, whether Numic or Hopi. This sort of rapid and complete assimilation is actually not as implausible as it seems; there are other examples of it in the prehistoric Southwest, and it must have happened quite a lot if the archaeological record is to be reconciled with the ethnographic one. All this suggests above all that the late prehistoric period, from AD 1300 on, was a time of immense change in the Greater Southwest, which makes it very difficult to figure out what was going on before that. Difficult, but not necessarily impossible. There are some ways to see through the haze.

Aikens, C. (1967). Plains Relationships of the Fremont Culture: A Hypothesis American Antiquity, 32 (2) DOI: 10.2307/277904

Armelagos, G. (1968). Aikens’ Fremont Hypothesis and Use of Skeletal Material in Archaeological Interpretation American Antiquity, 33 (3) DOI: 10.2307/278710

Gunnerson, J. (1962). Plateau Shoshonean Prehistory: A Suggested Reconstruction American Antiquity, 28 (1) DOI: 10.2307/278076

Madsen, D. (1975). Dating Paiute-Shoshoni Expansion in the Great Basin American Antiquity, 40 (1) DOI: 10.2307/279271

Madsen, D., & Simms, S. (1998). The Fremont Complex: A Behavioral Perspective Journal of World Prehistory, 12 (3), 255-336 DOI: 10.1023/A:1022322619699

Parr RL, Carlyle SW, & O’Rourke DH (1996). Ancient DNA analysis of Fremont Amerindians of the Great Salt Lake Wetlands. American journal of physical anthropology, 99 (4), 507-18 PMID: 8779335

Pendergast, D., & Meighan, C. (1959). Folk Traditions as Historical Fact: A Paiute Example The Journal of American Folklore, 72 (284) DOI: 10.2307/538475

Schroeder, A. (1963). Comment on Gunnerson’s “Plateau Shoshonean Prehistory” American Antiquity, 28 (4) DOI: 10.2307/278572

Read Full Post »

The Summer Solstice in Alaska

Sign with Summer Solstice Sunrise and Sunset Times, Anchorage, Alaska

Today is the summer solstice, and here in the “land of the midnight sun” the longest day of the year is very long indeed. In Anchorage, we don’t quite get to 24 hours of daylight, but it is nevertheless well after 11:00 pm as I write this and the sun is still up. North of the Arctic Circle they do have periods where the sun doesn’t set at all, for varying lengths of time depending on latitude. The northernmost community is Barrow, which gets several weeks of non-stop daylight in the summer (with a corresponding period of darkness in the winter, of course).

Given that the solstice falls right in the middle of this period of extreme daylight, it might be expected that Arctic peoples would mark it in some way, as many other societies around the world do (including the indigenous cultures of the US Southwest, as extensively documented in prior posts here). And this does indeed appear to be the case, though with a typically Alaskan twist.

Whalebone Arch with Umiak Frames, Barrow, Alaska

The Inupiaq Eskimos of the North Slope of Alaska, which lies entirely above the Arctic Circle, have traditionally had a whaling-based subsistence system, and to a considerable degree still do. They hunt whales in the spring (and in some villages also in the fall) using a type of traditional skin boat known as an umiak. These are large, open boats made of a wooden frame covered with the hides of walruses or seals, made according to a rigorous traditional protocol. They are used in other areas further south along the Bering Sea coast as well, but their close association with whaling is most pronounced on the North Slope. A recent article by Susan Fair discussed them in the context of their architectural uses as temporary shelters in various settings and their cultural importance in both whaling and the demarcation of ceremonial and other culturally important spaces at certain times.

One of those times is the Whale Feast, often known as Nalukataq (although that name technically refers only to the blanket toss that is one of the most famous elements of it). This ceremony is held only in years when at least one whale has been taken, and while its exact date varies it is scheduled for sometime around the summer solstice. As the name “Whale Feast” implies, the main focus of this event is on sharing the meat from harvested whales with the community, and it is an opportunity for the whaling captains (known as umialiit) who own the umiaks to demonstrate their generosity and show off their prowess.

Umiak on Sea Ice, Barrow, Alaska

Fair focuses in her article on the role the umiaks play in both the ceremony and the social system behind it, in which the small number of umialiit in a village form an elite within it and the umiak serves as a symbol of their power and prestige, but I was more interested in the timing of the feast. The spring whaling season at least in Barrow generally ends in late May or early June (it had recently ended when I was up there at the end of May and there were umiaks with flags raised indicating whaling success all over the place), so having the feast in late June makes a certain amount of just practical sense given the preparations necessary, but I do wonder if there is a deeper significance to the association with the solstice, perhaps as a vestige of a large role for indigenous astronomy in the pre-Contact era. I have not been able to find much information on archaeoastronomy or ethnoastronomy in Alaska, but given the high latitude and spectacular celestial phenomena that abound here I’m sure Native people have long been attuned to the sky. Recent changes, especially aggressive Christian missionization that sought to stamp out Native religion, has obscured a lot of the earlier cultural practices, but I wonder if things like the timing of the Whale Feast preserve bits and pieces of aspects of traditional knowledge that are otherwise forgotten. Certainly a topic that could use more attention, I think.

Read Full Post »

Chipped Stone

Stone Tools at Chaco Visitor Center Museum

When it comes to stone tools, archaeologists make a basic distinction between “chipped-stone” and “ground-stone” tools.  Chipped-stone tools are generally those that need to be sharp, such as projectile points, knives, scrapers, and drills, and are typically made of hard stone that keeps an edge.  Some ground-stone tools, such as axes, are also sharp, but for the most part ground-stone tools rely on other qualities of stone for purposes like hammering and grinding.  In the Southwest, ground-stone tools are usually made of sandstone, basalt, or other types of stone that are plentiful in the area immediately around a site.  These tools are heavy, and it generally wouldn’t have made any sense to import special types of stone to make them when, as is the case throughout the Southwest, there were plenty of rocks around.  The types of stone used for ground-stone tools are also generally those used for masonry in areas where masonry construction was typical, including at Chaco, where sandstone was the usual material.

Chipped-stone tools are a different story.  They are usually small and highly portable, and the best materials to make them are often scattered and not convenient for every habitation site.  Thus, widespread trade in chipping stone has very early origins.  Hunter-gatherers need very good stone for their projectile points, and also tend to be very mobile, so their chipped-stone tools tend to be very well-made and to be made of high-quality material from a wide variety of sources.  Settled agriculturalists such as the Chacoans don’t rely so heavily on chipped-stone tools for their subsistence needs (ground-stone tools like metates are much more important), and they typically put much less effort into both procuring stone for chipped-stone tools and making the tools themselves.

Flake of Narbona Pass Chert at Pueblo Alto

When it comes to Chaco specifically, chipped-stone shows a much more muted form of the pattern of massive imports of other goods such as pottery, wood, turquoise, and even food.  Cathy Cameron summarizes the patterns revealed by the chipped-stone assemblages from Chaco Project excavations in the 1970s in an article from 2001.  The basic pattern is that most chipped stone was from local sources throughout the occupation of Chaco, although “local” really refers to a wider area here than the canyon itself.  Good chipping stone is not plentiful in the canyon itself, but abundant sources of good chert and petrified wood occur a few miles to the north and would have been easily accessible to canyon residents in the course of their daily lives (i.e., special trips to gather stone would probably not have been necessary).  These local sources always dominate assemblages from Chaco.  Imported stone types do increase during the Chaco era from AD 1030 to 1130, especially at great houses such as Pueblo Alto.  The most abundant import at this time is Narbona Pass chert, a distinctive pinkish type of stone that comes from a very restricted area in the Chuska Mountains to the west.  The Chuskas are also the source of many other imports to Chaco, including huge amounts of pottery and wood, but the relative proportions of Narbona Pass chert in the overall chipped-stone assemblages are much more modest.  It comprises 21.1% of the total Chaco Project sample for AD 1020 to 1120 and 18.9% of the sample for AD 1120 to 1220.  This is much higher than any other type of imported stone ever reaches, and even higher than any single type of local stone for these periods (though much lower than the total proportion of local stone).

Other imported materials found in notable numbers include Brushy Basin chert from the Four Corners area, a type of yellow-brown spotted chert and a special type of petrified wood, both from the Zuni area, and obsidian.  Brushy Basin chert (along with other materials from the same formation) and Zuni petrified wood reach relatively high proportions of the overall assemblage at the same time that Narbona Pass chert does, and Zuni chert does too but at a much lower level.  The pattern of obsidian is different, and hard to understand.  It’s the most common exotic type of stone before AD 920, rising to as high as 7.6% of the assemblage in the seventh century.  Sourcing studies seem to show that most of the obsidian coming it at this point came from the area around Grants, New Mexico, near Mount Taylor, during this period.  Once the Chaco system really gets going, though, the proportion of obsidian plummets to less than 1%.  From 1120 on, however, it rises again, comprising 7.3% from 1120 to 1220 and 2% after 1220, still less than Narbona Pass chert but respectable.  This obsidian seems to come mostly or entirely from sources in the Jemez Mountains to the east of Chaco.

Log of Petrified Wood at Chaco

So what were the Chacoans doing with this imported stone?  Not much, as it turns out.  One of the oddest things about the amount of Narbona Pass chert, particularly, is that it doesn’t appear to have been used for anything special.  Like all other types of stone, both local and imported, it was used primarily for expedient, informal tools.  The Chaco Project found 2,991 pieces of Narbona Pass chert, and only 18 of these were formal tools.  This pattern is typical for most material types, though obsidian seems to have been more often used for formal tools, many of which were probably imported as finished tools rather than made in the canyon.  Of the formal tools the Chaco Project did find, of all materials, about half were projectile points, and the rest were various types of knives, scrapers, and drills.

So what’s going on here?  Hard to say.  Cameron evaluates the chipped-stone data in the context of the models for the organization of production proposed by other participants in the conference from which this paper originated, and she decides that Colin Renfrew’s pilgrimage model fits best, with some adjustments.  This conclusion is driven largely by the fact that so much of the Narbona Pass chert came from the Pueblo Alto trash mound and the idea that this indicates that it was deposited there as part of communal rituals.  I find claims like this dubious, and I think it’s more likely that people in Chaco were just importing this type of stone either because it is so visually striking or because of their strong social connections to Chuskan communities (or both).

Chuska Mountains from Tsin Kletzin

The thing I find most puzzling is the obsidian.  Obsidian was hugely important in Mesoamerica, and in view of the appropriation and importation of many aspects of Mesoamerican culture by the Chacoans, most recently dramatized with evidence for chocolate consumption, it seems very odd that the rise of the Chacoan system would coincide with a steep decline in the amount of obsidian imported.  This is particularly odd since the Grants area was very much a part of the Chaco world, and there were numerous outlying great houses and communities near Mt. Taylor.  If the Chacoans had wanted obsidian, they could easily have gotten it.  And yet, it seems they didn’t.

Or did they?  Keep in mind that this data is based mostly on Chaco Project excavations, although Cameron does incorporate some insights from a study of formal chipped-stone tools done by Steve Lekson that incorporated other data as well.  Lekson’s study noted that Pueblo Bonito in particular had an astonishing number of projectile points relative to most other sites, and I can’t help but wonder if part of the lack of obsidian at other sites was a result of more of it flowing to Bonito.  The excavations at Bonito were done a long time ago without the careful techniques of the Chaco Project, so the data isn’t totally comparable, but I’m going to look at the artifact records from Bonito (conveniently made available at the Chaco Archive) to see how common obsidian was there.

Arrowheads at Chaco Visitor Center Museum

Speaking of projectile points, another thing Cameron mentions is that many of them seem to have been imported to Chaco, some of them apparently embedded in meat.  Others were particularly finely made and left in burials and caches, suggesting that they may have been specially made for votive purposes.  That’s probably the case for many of the points Lekson identified as being particularly numerous at Bonito, but what I want to know is why arrowheads were such common grave goods and offerings there.  Was there a particular association between Chaco and hunting?  The great house residents do seem to have eaten a lot more meat than other people in the canyon and elsewhere.

On the other hand, arrows weren’t only used for hunting.  Cameron notes that one projectile point found by Neil Judd at Pueblo Bonito was embedded in a human vertebra, and the Chaco Project also found a woman at the small site 29SJ1360 near Fajada Butte who had two points inside her.  We often talk about how peaceful Chaco was and how little evidence there is for warfare during the Chacoan era, but I’m starting to wonder about that.  It’s certainly true that Chaco itself and most other sites occupied during its florescence show less obvious evidence for violence than sites afterward do, but there are still some signs that things may not have been totally peaceful throughout the Southwest in Chacoan times.  Arrowheads in vertebrae don’t get there on their own, after all.  Who shot those arrows?

Cameron, C. (2001). Pink Chert, Projectile Points, and the Chacoan Regional System American Antiquity, 66 (1) DOI: 10.2307/2694319

Read Full Post »

Best Acknowledgment Ever

Petroglyphs of Quadrupeds at Atlatl Rock, Valley of Fire State Park, Nevada

In 1978 H. Martin Wobst of the University of Massachusetts at Amherst published a short article in American Antiquity entitled “The Archaeo-Ethnology of Hunter-Gatherers or the Tyranny of the Ethnographic Record in Archaeology.”  Despite the evocative title, the article itself is a highly theoretical argument about the proper relationship between archaeology and ethnography that is unlikely to be of much interest outside those fields.  Basically, Wobst argues that the archaeology of hunter-gatherer societies is overly dependent on concepts drawn from ethnographic study of modern hunter-gatherer societies, even though that ethnographic research has inherent limitations in what it can observe about those societies and is further limited by the specific priorities of the scholars who conduct it.  He therefore says that archaeologists should play a larger role in developing theoretical approaches to these societies based on archaeological data, which has its own limitations but is nevertheless better suited to studying certain topics, such as large-scale regional interaction, than is ethnography.  From the perspective of archaeology, Wobst’s article is clearly situated in the processualist tradition, with its emphasis on using archaeological evidence to reconstruct social behavior and contribute to general anthropological theory.

The most interesting part of Wobst’s article, however, is the acknowledgments at the end, which begin with this remarkable dedication:

I would like to dedicate this paper to Provost Dr. Paul Puryear, without whose failing support of Social Sciences at the University of Massachusetts, Amherst, I would have been done much earlier.

It seems that Paul Puryear was indeed in some sort of administrative position at UMass at the time, but beyond that I have no idea what Wobst is talking about here.  Still, it’s a welcome change from the anodyne expressions of gratitude that usually dominate these parts of papers.

Wobst, H. (1978). The Archaeo-Ethnology of Hunter-Gatherers or the Tyranny of the Ethnographic Record in Archaeology American Antiquity, 43 (2) DOI: 10.2307/279256

Read Full Post »

Atlatls to Bows: More on the Skagit River Atlatl

Starbucks, New Brunswick, New Jersey

My post on the atlatl found at the mouth of the Skagit River north of Seattle seems to have led one reader to ask about it in a forum for modern atlatl makers and users.  The responses are interesting.  One respondent linked to an article from the 1960s with more detailed information which is available free online.  This article, by Charles Borden, has some very good pictures of the atlatl, which was at some point acquired by the University of British Columbia Museum of Anthropology, which has even better pictures and more information on its website.  Borden’s analysis focuses mainly on the iconography of the elaborately carved figure, which he puts in the context of ethnographically known imagery from various Northwest Coast cultures representing sea monsters and other mythological creatures with similar characteristics to the one on the atlatl.  He argues, not entirely convincingly, that it represents an early form of the important creature known as the Sisiutl, which is usually represented as a two-headed snake but which can take on other forms as well.  Whether or not he is right about that particular identification, Borden does make a convincing case that the atlatl fits easily into the artistic traditions of the Northwest rather than being an import from elsewhere.  He also argues that it is likely very old, and tentatively suggests that it may be contemporaneous with the Locarno Beach site in Vancouver, which produced an atlatl hook made of antler.  The Locarno Beach site defined the Locarno Beach Phase, which now seems to be dated to around 3500 to 2500 radiocarbon years before present.  As I mentioned in the previous post, the Skagit River atlatl was apparently later radiocarbon dated directly and assigned to the Marpole Phase, which dates to around 2000 to 1500 radiocarbon years before present.  (According to the UBC Museum website the exact date was around 200 AD.)  Borden was therefore off by quite a bit in suggesting that the atlatl was contemporaneous with Locarno Beach, but of course he had less information to go by than is available now.

Also, John Palter recently commented on a post in which I discussed an article of his on atlatl weights, pointing to a more recent article in which he bolsters his theory that they were associated with flexible atlatls by discussing the attitudes of modern atlatl users toward the advantages of flexible, weighted atlatls over more rigid types.  As with the forum discussion on the Skagit River atlatl, this shows the interesting insights on atlatl use that can come from the large corps of amateur atlatl users and their extensive experimental experience with atlatls.  This is a very different approach to learning about atlatls than the abstract study of surviving ancient specimens more typical of archaeologists, and I think the two approaches used together can be quite complementary. I’ve mentioned this issue before with regard to interpretation of an atlatl petroglyph.

Read Full Post »

About Those Chaco Burials

Old Bonito from Above

In discussing a recent paper using stable-isotope techniques to evaluate subsistence in the Southwest during the Basketmaker period, I mentioned that one of the control samples used for contextual comparisons of the Basketmaker results came from Chaco Canyon great house burials.  I don’t know how on earth the Utah-based researchers managed to get permission to test these burials, as this is a highly sensitive political issue in Southwestern archaeology in general, but somehow it seems they did, and the information they got is enormously useful in understanding some aspects of the Chaco system.  It appears to only be reported in this Basketmaker paper so far, and only as comparative data, although there is a reference to a manuscript in preparation by the same authors focused on the Chaco data specifically.  This doesn’t appear to have been published anywhere in the three years since the Basketmaker paper was published, as far as I can tell.

This type of analysis of Chaco burials is remarkable enough, but even more remarkable is that these aren’t just any Chaco burials.  Two of them are the two most remarkable burials found anywhere at Chaco and arguably in the whole Southwest: Skeletons 13 and 14 from Room 33, which had the largest and most elaborate grave assemblages known in the region.  Also included were two burials from the adjacent Room 56 and one from Kin Bineola, a nearby outlying great house which is generally described as “unexcavated” but which did see some largely undocumented digging by the Hyde Expedition in the 1890s resulting in a few specimens now in the collections of the American Museum of Natural History.

Kin Bineola from Plaza

These remains were all tested for carbon and nitrogen isotope ratios, like the Basketmaker specimens and some other comparative samples from Pueblo period sites in the Kayenta area and Canyon de Chelly.  All the samples showed carbon isotope ratios in the same general range, indicating a heavily maize-based diet.  The nitrogen ratios, however, which are used to determine the amount of meat in the diet, varied considerably, with the non-Chacoan Pueblo remains patterning with the Basketmaker examples in showing a diet with little meat but the Chacoan ones showing evidence of much more consumption of meat.  This supports what had already been suspected based on the generally healthier appearance of great house burials compared to those found in other Pueblo sites, even small-houses within Chaco Canyon, namely that the people, whoever they were, who were being buried in the great houses were not only given much more elaborate and numerous grave goods in death but were also considerably healthier in life.  This in turn provides strong support for interpretations of Chacoan society that see it as having had a strong hierarchical component, with the great house burials coming from the higher ranks of society.

That’s all well and good, and it provides important information bearing on some major questions in Chacoan archaeology, but what I find more impressive about this data is that most of the Chacoan burials (all except one of the two from Room 56) were also radiocarbon dated.  The advent of the Accelerator Mass Spectrometry (AMS) technique, which requires much smaller amounts of organic material than traditional radiocarbon dating, has made it feasible to do direct dating both on small amounts of material (e.g., pollen) and on important specimens like human remains that are too valuable both politically and scientifically to sacrifice large quantities of bone for dating.  Like similar dates that have been taken on corn cobs, these direct dates provide important chronological anchors in understanding the development of Chaco and its system.

Wall Niche, Pueblo Bonito

Unfortunately, while the paper does report calibrated 95% date ranges in addition to raw dates, it reports midpoints of those ranges (which are not very meaningful) rather than intercepts, so it isn’t really possible to get a sense of probable dates more precise than the 95% ranges.  (Also, the reported midpoints don’t appear to actually be the midpoints of the reported 2σ ranges; maybe they’re from the unreported 1σ ranges?)  Still, that’s something, and there are some interesting implications.

The one specimen from Room 56 that was dated had a range of AD 1023 to 1208, which probably puts it sometime during the height of the Chacoan era (AD 1030 to 1130) or perhaps a little later.  This is significantly later than the initial construction of this room, which took place during the earliest period of construction in the ninth and early tenth centuries, but from the ceramic types associated with the burials in this cluster of rooms it seems it was used for burials throughout the period of major occupation, so this is a very plausible date.  These bones apparently came from Room 56, and are listed in a specimen list as coming from the debris in that room, but the description of them in that list reads “Human Bones with #53 the dark ones,” and the undated specimen from the same room on that list has a note reading “Some were found in R. 53, thrown from R. 56.”  The first description is cryptic and I can’t make any sense of it, but the second seems to imply that these bones all originally came from Room 56 but some were thrown into Room 53, probably by Warren K. Moorehead during his rather crude excavations in this part of the site.  Regardless of the specifics, it seems there is little contextual information for these remains, so not much more can be said about them.

Lintels Sampled for Tree-Ring Dating, Kin Bineola

The Kin Bineola specimen has a date range that overlaps considerably with the Room 56 one but has a generally earlier range: AD 891 to 1147.  Much of the construction of Kin Bineola apparently dates to the tenth century, judging from both masonry style and the few tree-ring samples, and some seems to date to the early twelfth century, so either end of this range is quite plausible, although the bulk of evidence suggesting the importance of this site in the tenth century, a period of relative quiet for construction at Chaco itself, makes me inclined to think an earlier date is more likely.

The most interesting dates are from the Room 33 specimens.  Since these are such important burials for understanding Chaco, knowing when they were interred is very desirable.  They were the two lowest burials in the rooms and the only ones that were completely intact when excavated; the twelve burials above them were substantially jumbled, although they still had plenty of grave goods associated with them.  This implies that they were the earliest people to be buried in the room, and the pottery associated with them was relatively early but can’t be dated very precisely beyond that.  It is not clear from any of this how early they were buried, expecially whether it was before or after the major expansion of Pueblo Bonito beginning in the 1040s that may have involved substantial changes in the function of the building, perhaps including a change in the function of some rooms in the older part of the building into burial chambers.

Northwest Part of Pueblo Bonito Showing Expansion of Outer Wall

The date ranges reported here are AD 690 to 944 for Burial 13 and AD 690 to 940 for Burial 14.  Statistically these are virtually identical, and they strongly imply that the two were buried at the same time, which makes sense given their relative position and similar grave assemblages.  This is also really early, with the early part of the range extending long before the earliest known construction dates for Pueblo Bonito.  Since these clearly seem to be primary rather than secondary burials, this probably just means that the true age doesn’t lie at the early end of the 95% range.  That puts the most likely time of burial at between AD 850 and 940 or so, or between the earliest construction dates and the end of the date range.  This is still well before the expansion of the building, and it doesn’t extend much after the latest dates for the initial construction stage.

The upshot of all this is that these two burials appear to be significantly earlier than has generally been assumed.  They seem to date to a very early period in the history of Pueblo Bonito, and it’s even possible that Room 33 was initially constructed as a burial chamber for them.  George Pepper, who excavated it, thought the room had not originally been intended as a burial chamber, but he didn’t explain what led him to that conclusion.  Whatever the original function of Room 33, it seems clear from this evidence that it became a burial room very early on, and that these two enormously elaborate burials were part of Pueblo Bonito for at least the vast majority of its period of occupation.  I think this may have some important implications for understanding the construction sequence of the building and possible changes in its use over time, and perhaps even in understanding the rise and nature of the Chaco system as a whole.  Piecing together what exactly those implications are, however, will require considerably more thought and study.

Coltrain, J., Janetski, J., & Carlyle, S. (2007). The Stable- and Radio-Isotope Chemistry of Western Basketmaker Burials: Implications for Early Puebloan Diets and Origins American Antiquity, 72 (2) DOI: 10.2307/40035815

Read Full Post »

The Dental Evidence for Agriculture

Novitski Hall, University of New Mexico School of Dentistry, Albuquerque, New Mexico

I’ve recently been discussing stable isotope analysis as a way to directly determine dietary practices from skeletal evidence, and that is certainly a powerful tool in learning about past societies, but there are some drawbacks to it.  Like all complicated laboratory procedures, it’s expensive, and it has the additional problem of being destructive.  If it’s done right, it only requires a small amount of bone, but it does involve destroying that bone in the course of analysis, which puts it in tension with recent political trends away from invasive and destructive types of research.  It is therefore good to have additional ways of evaluating dietary practices, despite the enormous potential of isotope studies.

One such line of evidence is much more low-tech, and quite simple, as well as being non-destructive.  It starts from the widespread recognition that different types of diets have different and readily detectable effects on teeth.  Specifically, diets high in carbohydrates tend to result in significantly more dental caries (cavities) than diets higher in proteins and fats.  A variety of factors are involved in determining the rate of caries in a given individual, including the form of the teeth and the presence of caries-resistant minerals such as fluoride in the environment, but diet is one important factor and the one that can most easily account for differences between populations and societies in the rate of caries.  The way this works is that diets rich in carbohydrates, especially refined carbohydrates such as ground meal or flour which stick to the teeth more easily, result in buildup of plaque that certain bacteria in the mouth feed on.  Those bacteria then release waste products including lactic acid, which eats away at tooth enamel can causes caries.  Fats and proteins also cause plaque buildup, but the bacteria don’t feed on this plaque, and it tends to be less acidic and therefore less conducive to caries formation.

The implication, then, is that societies that are dependent on agriculture, in which people eat large amounts of carbohydrates, will show much higher rates of caries than hunting and gathering societies in which people eat more fats and proteins.  This has indeed been confirmed by observation of caries rates in numerous contemporary and prehistoric populations.  There are some cases in which hunting and gathering populations can have relatively high rates of caries, such as a heavy dependence on gathered resources that are high in carbohydrates, such as acorns and pine nuts, but in general the difference between foragers and farmers is quite clear and can be used to determine to what extent a given prehistoric population depended on agriculture just by looking at their teeth.

Durango Herald Offices, Durango, Colorado

One relatively recent study looking at this issue in the context of the Southwest is by Karen Gust Schollmeyer and Christy Turner.  Turner is best known in the Southwest for his controversial ideas about cannibalism, but he has also had a longstanding interest in dental studies which I’ve discussed before.  This paper looks specifically at the dispute over the timing of agricultural dependence in the Southwest and whether it arose at the same time as the “Pithouse to Pueblo Transition” between the Basketmaker III and Pueblo I periods, generally dated to around 750 AD.  The hypothesis Schollmeyer and Turner tested is that the Basketmakers had a mixed farming and foraging economy with relatively little dependence on agriculture but that later Pueblo populations were heavily dependent on farming.  This predicts that Pueblo populations should have substantially more caries than Basketmakers.  The sample they used to test this was a large collection of human remains from various sites in southwestern Colorado, mostly in the Durango area and the La Plata Valley, in the collections of the Harvard Peabody Museum and the American Museum of Natural History.  Since these were mostly excavated before 1930 and information on their exact origin and time period is often vague, Schollmeyer and Turner grouped them into just two groups, Basketmaker and Post-Basketmaker, and ran a series of statistical tests on the number and placement of caries in each group.

They found that there was basically no difference.  Both groups had very high rates of caries, whether measured as total number of carious teeth, total number of carious teeth and teeth that fell out during life (which often results from caries), or total number of individuals with carious teeth.  Statistically most of these were indistinguishable from each other, although it’s important to note that this can’t be considered a truly random sample and statistics drawn from it shouldn’t be taken too literally.  Comparisons of caries on specific types of teeth and on different parts of teeth also showed high rates in both groups.  There were no significant differences regarding types of teeth.  There was a significant but weak difference in parts of teeth, with the later individuals having more caries on the parts of the teeth facing other teeth rather than facing outward.  There was also a similarly significant but weak difference in the number of individuals with caries, which was lower in the later group, implying more caries per person with caries than in the Basketmaker period, since the overall number of carious teeth was not different.  I don’t think too much should be made of either of these differences, given the nonrandom nature of the sample, and Schollmeyer and Turner are properly cautious in interpreting them.  They do make the interesting suggestion, however, that if there is anything to these differences they may imply differences in processing of maize over time, with later groups processing it more efficiently and intensively, using more effective tools, perhaps in response to increased populations.  They further suggest that this may be behind some of the dispute in the literature over the timing of dependence on agriculture, since some of the evidence put forth as showing a late date, coincident with the Pithouse to Pueblo Transition, is based on the use of larger and more efficient grinding tools.  This is all pretty speculative, and I don’t think it’s really any more likely than the alternative explanation that the significant differences are just statistical noise, but it’s an interesting thought.

Railroad Bridge, Durango, Colorado

Overall, this evidence supports the other recent studies showing that Southwestern populations seem to have been dependent on agriculture by at least as early as the Basketmaker II period.  It’s therefore not exactly groundbreaking, but it is useful to have as many lines of evidence as possible brought to bear on important questions like this, especially when most of them seem to point in the same direction.

Schollmeyer, K., & II, C. (2004). Dental Caries, Prehistoric Diet, and the Pithouse-to-Pueblo Transition in Southwestern Colorado American Antiquity, 69 (3) DOI: 10.2307/4128407

Read Full Post »