Local Action

Quinhagak, Alaska

I’ve mentioned before that the prehistory of Alaska is much less well-understood than that of many other parts of North America, but there have been some interesting recent efforts to expand the amount of data available and the interpretations it can support. One of the most interesting is the excavation of the Nunalleq site in the small, remote community of Quinhagak. This project is distinctive in that it has been driven primarily by the local community, which saw that the site was in danger of being lost from accelerated erosion (driven in part by climate change). In partnership with archaeologist Rick Knecht from the University of Aberdeen in Scotland, local people led by the village corporation, Qanirtuuq Incorporated, worked to excavate this extremely well-preserved late pre-Contact site, which dates to the sixteenth and seventeenth centuries AD. The number of elaborate, well-preserved artifacts is astounding, and it is by far the richest site of the ancestral Yup’ik people of southwestern Alaska known to date.

Even more interesting, the artifacts are being displayed in a newly opened museum right in Quinhagak, rather than being stored in a distant location where they are not accessible to the descendant community. This not only gives the local people an opportunity to understand and access their heritage, but it also provides a tourist destination that can bring in much-needed economic activity to this very poor part of the state. This isn’t a model that can be replicated everywhere, but it’s a fascinating success story of archaeological research and heritage presentation driven by a local indigenous community in cooperation with outside academic experts. Definitely worth noting.

Qanirtuuq Incorporated Building, Quinhagak, Alaska

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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

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Arctic Artifacts

Kotzebue, Alaska

From time to time I like to point out interesting resources I come across, even if they’re not directly related to Southwestern archaeology. One that I just saw via an article in my local paper today is a new website with pictures and information on artifacts discovered in 2013 during construction of a fiber optic line in Kotzebue, Alaska by the Alaska-based telecom company GCI. The artifacts, mostly bone tools, date to the thirteenth century AD based on two radiocarbon dates, and are associated with the Thule culture, which is directly ancestral to the Inupiaq people who now live in Kotzebue and the surrounding region.

Wind Farm, Kotzebue, Alaska

I’ve been to Kotzebue several times, and it’s an interesting place. It is located slightly north of the Arctic Circle and serves as a “hub” community for the Northwest Arctic region of Alaska, which means it’s a larger community (with a population of about 3,000) that provides services to the smaller villages in the region. Relevant to my own work, Kotzebue has also been a pioneering community for renewable energy development in Arctic environments. Like most rural Alaska communities, Kotzebue is not interconnected to a larger electric grid, so it runs its own system, which has historically been primarily based on diesel generation. However, the local electric utility has been integrating wind turbines into its diesel-based power system for about 20 years now, and wind currently provides a substantial portion of its total power production (18.5% in State Fiscal Year 2015). It doesn’t get as much attention as Kodiak, another pioneering Alaska community that has used a combination of hydro and wind power to make its electrical system virtually 100% renewable, but it’s nevertheless an impressive achievement in a very challenging environment.

Aerial View of Wind Farm, Kotzebue, Alaska

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Foreshadow: Women

“Pithouse Life” Sign at Mesa Verde

Chapter 10 of Crucible of Pueblos, by Richard Wilshusen and Elizabeth Perry, looks at the position and roles of women in early Pueblo society, with a particular focus on how those roles seem to have changed with the economic and demographic changes of the late Basketmaker III and early Pueblo I periods that recent research is bringing into focus. It’s a thought-provoking chapter but in some ways rather odd, with many of its most intriguing proposals resting on what seems like fairly thin evidence.

The chapter looks at three main topics: food production, human reproduction, and gender relations in social power. Its overall thesis is that in the northern Southwest between AD 650 and 850 interrelated changes in food production systems and human reproductive rates led to major changes in gender roles, particularly regarding the division of labor between men and women, that may have led to settlement aggregation into villages and to changes in social power related to trade and ritual. The resulting social structure, in place by the end of the Pueblo I period in at least some areas, was the earliest form of the “Pueblo” society as known from modern ethnography, with its strict division of labor by gender and extension of this gendered ideology to many other domains of life.

Of the three main topics, the authors devote the most attention to the first, and it’s here that their arguments are strongest and most clearly supported by the archaeological evidence. The key change in food production during the period in question is the intensification (not introduction) of maize agriculture as the primary subsistence activity, supplemented by the growing of other crops like beans and squash, by the raising of domesticated turkeys, and by hunting and gathering of wild foods. Recent research has clarified the sequence and extent of this change, although a lot of questions still remain.

As the authors note, one of the most puzzling results of research on early agriculture in the northern Southwest is that maize is now clearly established as having been introduced as early as 2000 BC in several widely spaced parts of the Colorado Plateau (including Chaco Canyon), but for hundreds of years it appears to have remained a minor part of the diet of the groups that used it. It was only in the Basketmaker II period, between 300 BC and AD 300, that maize use became widespread, and even then, according to Wilshusen and Perry, local groups varied widely in the contribution of maize to their diets. There may have been a distinction between immigrant groups from the south that had a heavily agricultural subsistence base and local hunter-gatherers who were gradually incorporating some farming into their lifestyles.

This slow and incomplete adoption of agriculture is in contrast to the situation in other parts of the world where agriculture, once introduced, spread rapidly and quickly replaced hunting and gathering. It’s still not clear why, although Wilshusen and Perry note that as a tropical plant originating in Mexico, maize would have been poorly suited for the harsher climate of more northern latitudes, and that it would have taken some time for people to breed hardier varieties. It is also apparent that the variety of maize initially introduced was small and not as obviously superior to local wild plant foods as later varieties, and that it was initially introduced without an accompanying “package” of other domesticated foods, as was the case with agricultural spreads in other areas. Domesticated squash seems to have been introduced not long after maize, but separately, and domesticated turkeys appear to have been introduced from a different direction altogether, although the timing and details of their domestication remain very murky.

Be that as it may, the main point Wilshusen and Perry make in regard to this slow adoption of maize is that it is likely that women, who based on cross-cultural studies of hunter-gatherers tend to be responsible for gathering of plant foods, were involved in the initial use of maize in the northern Southwest. However, this small-scale introduction of a new food, even one associated with a new type of food production, probably wouldn’t have had a major impact on existing gender roles or division of labor. That would come later.

The full “Neolithic package” appears to have arrived in the northern Southwest between AD 300 and 600, with components including a larger, more productive variety of maize known as Harinosa de Ocho; beans, newly introduced from the south; greater use of turkeys for both meat and feathers; and greater investment in facilities for food storage and processing. The greater productivity enabled by these innovations led to rapid population growth and the spread of agricultural groups over the landscape, in striking contrast to the lack of such growth with the initial introduction of maize much earlier. Wilshusen and Perry associate these developments with the transition from Basketmaker II to Basketmaker III, as well as with the major changes in the roles of women that they document.

Additional support for these changes in food production come from complementary changes in storage facilities and grinding tools. As documented in the well-studied Dolores area, the importance of storage seems to have risen over the course of the late Basketmaker III and Pueblo I periods from AD 650 to 875. Storage facilities changed from small pit rooms isolated from the main dwellings to more secure and more solidly built storage rooms directly attached to living rooms and only accessible from them. These typically consisted of two storage rooms at the back of each living room, the beginning of the “suite” layout that would continue to be a key architectural feature into Chacoan times. It is possible that at least initially these paired rooms were used to store two years’ harvests, one in each room, so as to provide a subsistence buffer against drought and other unexpected problems.

There was also a shift over this period in grinding implements from basin metates with one-handed manos to much more efficient trough metates with two-handed manos. Beyond this shift, a greater variety of grinding tools became common over time. Together with the storage data, this indicates an increased importance of grinding as a component of food preparation. In the modern Pueblos grinding is a female-associated activity, part of an overall suite of food-preparation tasks accomplished by women that also includes shucking, shelling, drying, and storing corn. Of these tasks, however, grinding is considered particularly important to the female role, and it is an important part of female puberty ceremonies (of which the Navajo Kinaaldá, of clear Pueblo origin, is probably the best known). Men, on the other hand, are responsible for planting and harvesting the corn, as well as protecting the fields. This seems to be a change from the presumed hunter-gatherer system in which women were generally responsible for gathering plant foods as well as processing them, and Wilshusen and Perry suggest that it may have arisen in early Pueblo times as fields at greater distances from residence locations in villages became increasingly vulnerable to attack by enemies, prompting men’s role as warriors to encompass guarding fields and, in time, tending them as well.

Another important female task in modern Pueblos is making pottery, and this too seems to have become increasingly important with the expansion of agriculture in early Pueblo times. With more use of crops and additional cultigens such as beans, pots would have become more important for food preparation, and with the number of vessels needed and their short use-lives of 1 to 6 years women would have had to be constantly making new ones. (This is of course assuming that most pots for domestic use were made by the family unit itself, which may well be true for this early period but was not necessarily later on.) Based on detailed study of an isolated Pueblo I hamlet in the Central Mesa Verde area, Wilshusen and Perry estimate the following assortment of vessels for a typical household at any given time:

• 2 to 7 small cooking jars
• 1 to 4 medium cooking jars
• 0 to 2 large cooking jars
• 1 bowl
• 0 to 3 ollas for water
• 2 to 3 other vessels
• 10 to 20 sherds from broken pots used as containers or tools

Keeping a household supplied with all these pots would have been a major part of a woman’s domestic labor, in addition to the food processing tasks mentioned above, along with other major responsibilities such as caring for children.

And speaking of children, Wilshusen and Perry go on to discuss human reproduction and the apparent changes in it associated with the other changes they identify. The two main changes they note are shifts in the use of cradleboards and an apparent increase in the societal fertility rate. This part is somewhat less thorough than the food production part of the paper, but it does still identify some intriguing evidence for change.

First, cradleboards. The authors note that study of these items, in which infants were bundled while they were very young,  has been surprisingly limited, despite their relevance to an important event that has long been recognized: the beginning of evidence for “cranial deformation,” or the reshaping of skulls as a result of prolonged contact with certain kinds of cradleboards in infancy. The shift from “undeformed” to “deformed” (the terminology is very problematic, as there is no evidence of health problems from the practice) crania is traditionally associated with the transition from Basketmaker III to Pueblo I, and early in the history of Southwestern archaeology the change in head shape was even taken as evidence for a population replacement. (That was in the early twentieth century when anthropologists put much more emphasis on skull shapes in defining populations than they do now.) It is now generally thought that the distinction is actually due to the use of soft versus hard cradleboards, but recent research that Wilshusen and Perry discuss suggests that both types of cradleboards were present in both Basketmaker and Pueblo times. Thus, the shift in cranial shape is actual due not to a change in the type of cradleboard but in how it was used. The main changes that actually seem to have occurred in the Pueblo I period are:

• Foot rests on cradleboards disappear.
• Hoods become more common.
• Construction is more expedient.

According to Wilshusen and Perry, these changes together indicate that women had less need to move while carrying children in cradleboards, but that they needed more cradleboards overall, possibly indicating that they had more children. This part of the paper does not go into much detail about where these conclusions come from, but the overall conclusions is that this is further evidence that women were more tied to the domestic sphere in Pueblo I, and possibly that they had more children.

On that note, demographic data appear to indicate that the population increases seen in at least some part of the Pueblo world during Pueblo I were due largely to natural increase after initial immigration into new areas. The best data come from the Central Mesa Verde and Eastern Mesa Verde areas, both of which seem to show this pattern. Prehistoric demographics are notoriously hard to reconstruct, but based on the large recent data sets from major excavation projects Wilshusen and Perry propose that a Neolithic Demographic Transition (a major increase in fertility associated with the beginning of intensive agriculture) began in the northern Southwest around AD 300, with major consequences over time for women in particular, given their gender-defined economic roles. This is comparable to evidence seen in other parts of the world with the beginning of agriculture. The key point here for the role of women is that with increasing rates of both childbirth and survival of children beyond infancy, families would have become larger, increasing the amount of domestic labor required of women to maintain their households given the gendered division of labor presumed to have developed. This would be one explanation for the increased importance of food processing mentioned above.

Finally, Wilshusen and Perry talk about exchange and social power. The discussion here is very abbreviated, and relies heavily on references to the next chapter in the book (which is a little odd), but the basic idea is that rock art evidence shows a shift in social power to male leadership of ritual in late Basketmaker III, continuing into Pueblo I. Female economic roles expressed in matrilocal residence may have driven men to make external trade alliances, which over time developed into new ritual systems focused on important lineages within villages rather than large public rituals at central places not necessarily associated with a specific lineage or community. Matrilineal lineages were still important, and the focus of key rituals, but changing gender roles may have involved an increased role for the men of the lineage in certain types of rituals. Burial evidence from Ridges Basin may support some of these ideas, with striking differences in male and female burials, particularly in the types of exotic goods included. Both women and men were buried with exotic items occasionally, but the specific types of items varied, suggesting gendered access to different trade systems. There are also geographic differences within the basin suggesting different community connections and ideological systems. This section is intriguing but very sketchy, even compared to the rest of the paper. More detailed discussion of some of these ideas will have to wait for the next chapter.

Overall, the conclusion of this chapter is that over the course of the early Pueblo period gender roles shifted in a way that evolved into the system(s) that are well known from the modern Pueblos. This may have been a response, in part to the demographic shift resulting from the development of intensive agriculture, with its resulting higher birthrates and changes to the roles of women. Women’s labor was key to this transition, but it’s not clear that it was actually good for women as a class on net. There has been some discussion of the idea of “parallel status hierarchies,” in which men and women had different tasks but both allowed meaningful status through high achievement. However, later evidence from Pueblo sites shows that women were often excluded from access to high-value resources such as meat, and that their graves were generally less elaborate than men’s (a contrast to the Pueblo I situation in at least some areas). It doesn’t appear that many strictly comparable studies of these issues have been done of the Pueblo I period itself, so it’s hard to say how these changes felt for the women who were living through them. The authors of this paper seem to lean toward thinking the changes were not actually beneficial for those women, but the evidence is thin enough that it’s not clear.

Above I have summarized the arguments of this chapter as best I could, but it’s worth noting that the argumentation of the chapter itself is highly abbreviated, and summarizing it has required a lot of assumptions and interpretive leaps. It kind of reads like this paper is an abbreviated version of a longer argument, with some important parts left out. Nevertheless, it raises a lot of interesting questions that have rarely been addressed in Southwestern archaeology, especially regarding the early Pueblo period, and for that alone it is valuable.

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Foreshadow: Perishables

Plaited Sandals at Chaco Museum

Chapter nine of Crucible of Pueblos looks at perishable artifacts (i.e., those made of materials that are often not preserved in the archaeological record, such as yucca fiber, animal hair, and cotton) during the Pueblo I period. Written by Laurie Webster, one of the most prominent experts on prehistoric Southwestern perishables, this chapter functions partly as an inventory and description of all known perishables from Pueblo I sites, and as such it is highly technical in nature and not very accessible for a casual reader. For this summary, therefore, I will focus on the high-level conclusions that can be made about Pueblo I cultural dynamics and relationships from the perishable evidence, rather than the evidence itself.

Those conclusions are quite interesting, as it turns out, especially when it comes to the patterning of different types of artifacts. Webster covers several different types of artifact, but I will focus on two with the most interesting cultural implications: sandals and textiles.

First, however, a note about the data. As Webster notes, the Pueblo I period has historically been poorly represented in the perishable data compared to earlier and later period that are known for extraordinary preservation from caves and rock shelters, especially the Basketmaker II and Pueblo III periods. People made much less use of caves and rock shelters during Pueblo I, and as a result many more of their perishable artifacts have, well, perished, and those that do survive are mostly in poor condition. Indeed, most of the best-preserved Pueblo I perishables are from areas like Tsegi Canyon and Canyon del Muerto in northeastern Arizona where caves did continue to be used in Pueblo I, although the Pueblo I occupation in these areas is poorly understood and it is not always clear that artifacts assigned to Pueblo I by early excavators really do date to this period. Luckily, however, the nature of perishable artifacts means that they can be directly radiocarbon-dated, and Webster mentions several examples that have been and many more that could be.

With that caveat out of the way, sandals. These were generally made out of yucca fiber and appear to have been a key way people at the time signaled their cultural identity, based on the geographic patterning of different types, and they likely had symbolic importance as well at least for some groups, based on the elaboration of some examples, implying an immense amount of labor, as well as the depiction of sandals in rock art and the creation of clay effigies (often called “sandal lasts” although that doesn’t appear to have been their actual function). In particular, highly elaborate twined sandals were common in western areas during Pueblo I, a continuation of a tradition from Basketmaker times. Pueblo I examples are known from northeastern Arizona, the eastern slope of the Chuska Mountains in New Mexico, the Dolores area in Colorado, and Chaco Canyon. In contrast, only one example is known from the Animas River Valley, and none from further east, despite the large recent excavations in this area in conjunction with large development projects.

Animas River, Durango, Colorado

A different type of sandal dominates in these eastern areas, a twill-plaited design that appears to date back to the Basketmaker II sites near Durango, Colorado. This type dominates in the Ridges Basin and Blue Mesa area of the Eastern Mesa Verde region and is also found in the Navajo Reservoir area further south, as well as at Grass Mesa Village in the Dolores area. The last is particularly interesting given that there is other evidence that Grass Mesa was settled by people from areas further east. It is also interesting that McPhee Village, also in the Dolores area, shows mainly twined sandals, again supporting other evidence suggesting western connections for this site. Similarly, the one site in the Animas Valley showing evidence for twined sandals also has other evidence of western connections.

A third type of sandal, plain weave with a rounded or pointed toe, appears to also have a western distribution extending from southern Nevada to northeastern Arizona and southeastern Utah but not into Colorado or New Mexico. Less is known about this type than the other two and its cultural significance is not clear.

While in general Webster concludes that Pueblo I perishables mostly continue Basketmaker III patterns without major innovations, she does note one major innovation by late Pueblo I: the increasing use of cotton. While many of the cotton textiles from northeastern Arizona attributed to Pueblo I have questions about their dating and associations, there is one example of a sash from Obelisk Cave in the Prayer Rock District (extreme northeastern Arizona) that has been directly dated to the AD 700s (early Pueblo I). One particularly interesting thing about this sash is that it actually consists of a mixture of cotton and dog hair, clearly showing the transition from animal hair and cotton for textiles. While the form of this item and the use of mixed materials strongly implies that it was made locally, it is not clear if the cotton was in fact grown locally or imported from the Hohokam in southern Arizona, who had a well-established tradition of cotton agriculture by this time.

By late Pueblo I, however, there is strong evidence that at least some Pueblo groups were growing their own cotton. At Antelope House in Pueblo del Muerto, cotton cloth in contexts dating to the AD 900s was found along with cotton seeds and bolls, clearly implying that cotton was being grown in this area by then, as it continued to be throughout the Pueblo period. Interestingly, there is no evidence for Pueblo I use of cotton textiles further east, again implying some sort of major cultural boundary. This is in contrast to later periods, when cotton grown in northeastern Arizona was traded to various other parts of the Pueblo world.

So anyway, those are the major points of interest about Pueblo I perishables. I find the most interesting point from the perspective of Chaco to be the fact that it patterns with the western rather than the eastern style of sandal, which reinforces other evidence for western connections for at least some of the people who came to Chaco in late Pueblo I and contributed to its rise into a dominant regional center in the northern Southwest.

Chuska Mountains from Peñasco Blanco

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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.

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Archaeology of the (Past) Present

Mercer Museum, Doylestown, Pennsylvania

I was in Philadelphia for Thanksgiving, and the next day I went with my family to the quaint nearby town of Doylestown, where we visited two local museums: the Michener Museum (named after, yes, that Michener, who grew up in Doylestown and spent most of his life in the area) and the Mercer Museum. The Michener is basically a local art museum, and we went there to see an exhibit about Grace Kelly, who is a big deal in the Philadelphia area. Not really my kind of thing, but it was fine.

The Mercer, on the other hand, is a really unusual sort of museum. It was established by Henry Mercer, a Doylestown native who had a variety of interests and a good deal of money with which to pursue them. He studied law but never practiced it, instead going into archaeology in the 1890s. I haven’t found much information about his specific contributions to American archaeology, which was in its infancy at that time, except that he apparently supported the authenticity of the obviously forged Lenape Stone that allegedly contains an image of a mammoth and is now part of the Mercer Museum collections (though not on display).

In the late 1890s, however, Mercer came to the realization that the advancement of industrialization meant that most aspects of traditional life in the US were likely to disappear forever, and he began to collect what were then considered mundane objects for the museum of the Bucks County Historical Society. He collected huge numbers of things from all aspects of pre-industrial life, over time branching out to the US as a whole and eventually other parts of the world as well. His collection got so big that he built a new building to house it, using an innovative design and construction approach using poured concrete. He organized the collection thematically by the sorts of societal needs that objects served, and put together display cases by category.

The museum is still much as he designed it, although there have been various changes over the years. It’s a fascinating place, idiosyncratic and full of extremely detailed information. What I found especially interesting, however, was the way the museum’s own self-descriptions explicitly tied Mercer’s collecting of what most people considered “junk” to his earlier interest in archaeology. That is, one way to see what Mercer was doing was taking an archaeological approach to studying and preserving the material culture of the present and recent past, to ensure it would be understood in the future. This approach was quite ahead of its time for both history and archaeology, and the museum that resulted is fascinating and well worth a visit.

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This Chocolate Stuff Is Getting Weird

Utah Welcome Sign

The initial discovery of chemical markers for chocolate on potsherds from Chaco Canyon in 2009 was a hugely significant development in understanding Chaco. The evidence for the presence of chocolate, a Mesoamerican product that couldn’t possibly have been locally grown and is very unlikely to have been gradually traded northward through a series of intermediaries, gave a huge boost to the “Mexicanist” school of thought about Chaco, which holds that many of the unusual aspects of the Chaco system are due to influence from Mesoamerica.

The initial study only involved a few sherds, though, and understanding the exact role of chocolate at Chaco and its implications for Mexican contact needs a much deeper understanding of where and when cacao was present in the ancient Southwest. Thus, soon after the initial discovery further research by a different set of researchers (using somewhat different methods) began to test other pots from Chaco and elsewhere. They did find further evidence that at least some of the famous cylinder jars from Chaco were used in the consumption of chocolate, but they also found traces of cacao in vessels of similar form from the later Classic Hohokam period in southern Arizona, and, most surprisingly, also in vessels from the “small-house sites” at Chaco and elsewhere that are thought to have housed the lower classes of Chacoan society. The previous evidence for chocolate came from distinctive vessels at the “great houses” that are the hallmark of the Chaco system and seem to have been used by elites (though exactly what they used them for remains unclear and controversial). This is exactly the kind of setting where it would be unsurprising to find unusual, exotic things, and indeed the great houses clearly contained many such things in addition to the chocolate. Finding this sort of exotic foodstuff in more mundane pots at the small houses implies that it may have been more widely accessible than previously thought, which has important implications for understanding the nature of the Chaco system.

Well, now things have become even more complicated. The same researchers who did that follow-up study have done another, this time looking at a much earlier period and a different part of the Southwest. They used their same techniques to test for the presence of chocolate in pottery at Alkali Ridge Site 13 in southeastern Utah, a very important early village site dating to the eighth century AD. Site 13 was one of the earliest large villages established in the northern Southwest during the Pueblo I period, and its architecture shows some striking parallels to later Pueblo I villages such as McPhee Village in the Dolores, Colorado area, as well as to some of the early great houses at Chaco and elsewhere that developed even later. The early Pueblo I period in southern Utah is also associated with the introduction of a new type of pottery, San Juan Red Ware, which was widely traded from an apparently rather restricted production area and probably used for ceremonial purposes of some sort. In addition to being a different color from the more common gray and white pottery of the area, San Juan Red Ware also featured a distinctive design system in its decoration, one without obvious local antecedents. Combined with the distinctive architecture, this has led some archaeologists to posit that there was a migration into southern Utah during early Pueblo I from somewhere to the south, bringing these distinctive traits.

In that context, looking for cacao makes sense, as that would be a clear sign of ties to the south and cultural distinctiveness. Dorothy Washburn, who was the lead author on both this and the previous study,  has actually written mainly on design style in ceramics and other handicrafts, focusing on symmetry patterns. Based on the changes she has found in these patterns, she has argued for a very strong Mexicanist interpretation of Chaco, involving actual migration of people from far to the south bringing a distinctive pottery decoration style. She seems to have a similar view about Alkali Ridge, for similar reasons.

In any case, the study found that there was in fact evidence for cacao on several of the vessels found at Site 13, including some (but not all) of the redware ones. The conclusions, understandably, focus on the association between the new ceramic design system and the use of chocolate, but in fact the redware vessels don’t seem to be much more likely to have evidence of chocolate use than the other ones that were tested. It’s quite possible that San Juan Red Ware was associated with consumption of chocolate specifically, but it seems that other types of pottery were also used for chocolate-related purposes.

This is all very interesting, but it’s also confusing and hard to interpret, in a way that the authors of this paper don’t really address. Back when it seemed like chocolate was limited to cylinder vessels at Chaco great houses, that was easy to interpret: chocolate, like many other exotic goods found at these sites, was part of an extensive trading systems for elite goods, probably used for ritual purposes, which the elites of Chaco participated in (and perhaps dominated and directed). Finding it in the Hohokam vessels implied a similar system operating among elites at Classic Hohokam sites, which is consistent with some interpretations of Classic Hohokam society, plus the Hohokam in general show lots of evidence of contact with Mesoamerica in general so the presence of chocolate is much less surprising there than it was at Chaco. Finding it in the small houses at Chaco complicated the story somewhat and implied that the chocolate imported to Chaco wasn’t as restricted as had been thought, but since it was already known to be present at the great houses it’s not too surprising that the contemporaneous small houses had it too.

Alkali Ridge, though, is much earlier and much further north than any of these other sites. Getting chocolate there in significant quantities would have required a pretty elaborate and robust supply chain over a very long distance, much of which was inhabited by societies that are not generally considered to have been capable of this kind of long-distance coordination. Checking some of those intermediate areas (especially the Hohokam region) to see if they too had chocolate this early is necessary to understand the logistics of this.

There’s also the question of time. We now have evidence of chocolate from Utah in the eighth century, New Mexico (and to a lesser extent Colorado and Arizona) in the eleventh, and Arizona in the fourteenth. There are some big gaps there that need to be filled in to determine if these are three snapshots of a long-term and continuous tradition of chocolate consumption in the Southwest (which would have important implications about trade networks and relations with Mexico) or three separate episodes of chocolate being introduced from the south, possibly through population movement (which would have important implications for regional culture history in general). I think the most important place to look for evidence of continuity between Alkali Ridge and Chaco is in the large late Pueblo I villages in southwestern Colorado, especially the Dolores-area ones like McPhee Village. These sites have apparent connections to both earlier villages like Site 13 and later developments at Chaco. If they also reveal evidence for chocolate use, that would be a strong indication of continuity. The most important places to check for continuity between Chaco and the Classic Hohokam would probably be the Pueblo III communities in east-central Arizona, which again show connections in both directions. Both of these sets of sites are among the best-studied in the Southwest and there should be plenty of pots available for these analyses.

Finally, there is a methodological issue here. It’s possible that these tests aren’t actually detecting chocolate at all, but something else. The authors of the recent paper noted this possibility and looked into whether there are any plants native to the Southwest that might have chemical profiles similar to cacao that would throw off the analysis. They didn’t find any, but they note that many plants have not been analyzed in this way and it’s possible there is a different plant that is showing up in these analyses instead. Another possibility is that there is something about their method itself that is leading to false positives. It’s noteworthy that they have been finding much more extensive evidence of chocolate than the team, led by Patricia Crown and Jeffrey Hurst, that did the initial Chaco study found. That team hasn’t published any more about chocolate at Chaco since then, but I hear Crown was able to do some re-excavation in Room 28 at Pueblo Bonito this summer so there may be more from her on this in the future. Ideally I’d like to see a test of both methods on the same vessels to see how they match up.

The ultimate message here is that even important discoveries, like chocolate at Chaco, require many further studies and refinements to interpret properly. We’re nowhere near a full understanding of the true role of chocolate at Chaco or any other site in the prehistoric Southwest, but every study gets us closer.

Washburn DK, Washburn WN, & Shipkova PA (2013). Cacao consumption during the 8th century at Alkali Ridge, southeastern Utah Journal of Archaeological Science, 40, 2007-2013 DOI: 10.1016/j.jas.2012.12.017

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Let’s Talk about Pottery Some More

Black-on-white Sherd at Pueblo Alto

In keeping with what seems to be the recent pattern around here, my previous post led to some interesting discussion in the comments. Frequent commenter marcaeolog provided a link to a pdf version of Anna Shepard’s Ceramics for the Archaeologist, a classic work that challenges some of Florence Hawley’s theories that I discussed in the post. Andy Ward, who has done extensive experimental work attempting to recreate prehistoric pottery-making techniques, then chimed in with some information on his own efforts, focusing specifically on the question of what keeps carbon-based pigments from burning off during firing. Here’s part of his comment:

I have been doing research in just this area by collecting clays and firing them in open mesquite fires. While it is easier to keep carbon based paint on a pot in a reducing atmosphere this doesn’t account for polychromes. To make polychrome with a carbon based paint, like the ubiquitous Gila Polychrome, requires an oxidizing atmosphere. Certain kinds of clays have the ability to hold these carbon paints through a firing, bentonite clay in particular. Modern pueblo potters have used a slip called Cochiti slip which has these properties, ancient potters in cultures such as the Salado had access to similar slips.

As it turns out, Shepard had the same theory, based on her own experiments, which also provided solid evidence against Hawley’s theory, based on experiments with hydrofluoric acid, that it was compounds in the ash of the organic material that reacted with silica in the clay to protect the pigment from burning away. She acknowledged that this was a reasonable conclusion based on the information available to Hawley at the time, but Shepard’s own experiments comparing organic material with and without this sort of ash showed no substantial difference. Instead the biggest factor was clay type:

The most striking fact brought out by these tests is the effect of the type of clay on the permanence of the carbon. Bentonitic and other highly adsorptive clays retained a good black under firing conditions that completely oxidized the carbon on unnadsorptive, sedimentary clays. All of the clays that held the paint well required a high percentage of wafer to bring them to the plastic state and they had high shrinkage. These clays take up much more of the paint solution than the less adsorptive clays, and on drying, the clay plates are drawn tightly together, protecting the film of paint that surrounds them. The effectiveness of hydrofluoric acid in facilitating oxidation of carbon paints is explained by the fact that it attacks the clay, opening the surface and loosening the bond and thus exposing the carbon to air.

The upshot of this in cultural terms is that, contrary to what I said in an earlier post, it seems like the difference between mineral- and carbon-based black pigments is actually technological rather than cultural. Here’s Shepard again:

The relation of the type of clay to the depth of color of carbon paint from a plant extract is not a matter of merely theoretic interest to the technologist. It has a bearing on the distribution of this class of paint because it could not be produced in regions lacking adsorptive clays unless such clays could be obtained in trade. The use of plant extracts is not open to free choice or established merely by custom; it is limited by ceramic resources.

This is particularly interesting given the well-documented expansion of carbon-based pigments at the expense of mineral ones over the course of the late prehistoric period. If special clays were required to make this work, and those clays had restricted distributions, what accounts for the change? In areas that switched from mineral to carbon paint, such as Chaco, was this the result of a change in clay sources? The discovery, perhaps due to increased contact with other areas that had long used carbon, of which local clay sources worked for this? Importation of clay? Importation of finished pots? This raises a lot of questions, which to my knowledge have not received much attention in the archaeology of these areas, despite the fact that it’s now been several decades since Shepard’s research.

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So Apparently That’s Not Paint

Black-on-white Potsherd at Kin Bineola

“Never read the comments” is generally sage advice, so it’s likely that many of my readers have missed the interesting comment thread in response to my previous post. I won’t try to summarize it all here, but the gist is that a potter showed up and took issue with my use of the word “paint” to describe the pigments applied to prehistoric Pueblo pottery. Apparently, while archaeologists routinely refer to these pigments as paints, that’s not actually an accurate characterization and they are instead best described as types of “slip,” a term that archaeologists usually use only for the underlying layer of thin clay that the “paints” are often applied to. There’s a long history of archaeologists appropriating and misusing terminology from other fields, so it’s not surprising that they would have done this in this case too, but I’m not sure how best to proceed with the terminology, as it is pretty useful in practice to be able to distinguish the underlying “slip” from the “painted” designs on top of it. For now I’ll try using the (hopefully) more neutral term “pigment” for the “paint” and continue to use “slip” for the underlying clay.

Another issue that came up in the discussion, however, is separate from the terminology. This is the question of how the carbon-based pigments that are so well known from many parts of the Southwest could have adhered to pots after firing at all. After all, at the temperatures necessary to create usable ceramics any purely carbon pigment would burn right off. As I started to think about it, I realized that this was indeed a puzzle, and I went looking back into the literature to see if it had been addressed anywhere.

As it turned out, it had, and in the very first research on this subject, that of Florence Hawley in the 1920s. Hawley was an important figure in Southwestern archaeology throughout much of the twentieth century, and her early chemical studies of pottery pigments were fundamental in establishing the classification system by which they have been interpreted ever since. The most important aspect of this system was the division between “carbon-based” and “mineral-based” black pigments, although looking back at her initial publication on this topic from 1929, it’s clear that the dichotomy is more subtle than the terms imply. In fact both types of pigment contain both carbon and mineral elements, the difference being the relative proportions and the specific minerals involved. Both involve the boiling of certain plants, usually Tansy mustard or Rocky Mountain beeweed, to create a thick, black substance that can be applied to an unfired pot with a brush. The carbon type consists only of this substance, while the mineral type involves a subsequent step of adding ground iron oxide before applying it to the pot. Hawley also identifies a third type using manganese, which she speculates was used for certain types of pottery made of clay to which the usual carbon pigment wouldn’t adhere properly. (She also identifies a fourth type, so-called “smudged” pottery, that resulted from adding organic material after firing and letting it sink into the clay. This type is generally associated with the Mogollon culture in the highlands of east-central Arizona and west-central New Mexico and is quite different from the others in appearance.)

The chemical tests Hawley suggests to distinguish among these types of pigment are complicated and involve the use of dangerous acids, so they have not caught on as routine methods for archaeological analysis in more recent years. The tests appear to have been worked out and conducted mainly by Hawley’s father Fred Hawley, who was a chemist at a smelter in one of the mining areas of Arizona. Instead of these tests, archaeologists have generally tried to learn to distinguish the more common types by sight. As one of the papers I discussed earlier found in a test of this method, it works pretty well except in more marginal cases that are difficult to interpret using the standard visual criteria. The methods that have been proposed more recently using modern imaging technology have also not yet become very popular. In general the visual criteria seem to work fine.

As I noted in the previous post, the fact that both organic and mineral pigments seem to work to create black designs, but the mineral type is basically the same as the carbon one, raises the question of why there were two types at all. I suggested that cultural tradition rather than technological considerations probably was the main factor. Hawley doesn’t address the question in those terms, but she does argue that the different pigment types correspond to different cultural traditions, and the second half of the paper consists of her conclusions about cultural provinces and their spheres of influence based on pigment types through time. Her basic scheme of carbon pigments predominating in western areas and mineral pigments further east has generally held up, but otherwise her interpretations show how little was known at the time about Southwestern prehistory. She was clearly writing before tree-ring dating had established a firm foundation for the absolute chronology of cultural developments and pottery types, and the assumptions she makes about which sites were contemporary are strikingly wrong in light of that chronology. This makes her conclusions about changing patterns of cultural influence through time basically useless.

All that said, what about the question I mentioned earlier? How does the carbon pigment survive firing? Hawley’s answer, backed up by the chemical tests, was that it actually contains some mineral inclusions in addition to the carbon, especially silica and carbonates that melt in the process of firing and form a very thin film over the carbon that protects it from burning away. She considers this layer too thin to be considered a glaze, but it appears to serve the same basic function. It only works, however, when firing is in a reducing atmosphere, i.e., with oxygen prevented from reaching the surface of the pot. It’s not totally clear from her explanation where these mineral compounds come from, but the implication seems to be that some are from the plants from which the pigment is made and others are perhaps from the clay of the underlying pot. In the case of the mineral pigments, these potential sources are complemented by the trace silica in the iron oxide. As the more recent papers note, this interpretation has been questioned by others, most significantly Anna Shepard (another pioneering ceramic analyst at the same time as Hawley). It seems clear, however, that getting these pigments to survive firing requires some sort of chemical reaction along these lines, involving compounds in the pigment and/or the clay, along with a reducing atmosphere during the firing process itself.

It turns out pottery is pretty complicated! Archaeologists usually use pottery types primarily as a means to date sites and establish trade relationships, but studying potsherds intently with an eye to technological issues can reveal a lot of additional and potentially useful information.

Hawley, FM (1929). Prehistoric Pottery Pigments in the Southwest American Anthropologist, 31 (4), 731-754 DOI: 10.1525/aa.1929.31.4.02a00110

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