acid with the dissolved mineral. Then 

 we add another acid which will dissolve 

 another mineral, then still another, and 

 so on until the original sample is reduced 

 nearly to pure pollen. 



As soon as these methods were per- 

 fected, archaeologists in northern Eur- 

 ope began to collect sediments associated 

 with archaeological sites and to subject 

 them to pollen analysis. 



But on this continent the value of pol- 

 len analysis was slower to be recognized. 

 Most European pollen samples came 

 from organic sediments, such as peat and 

 lake muck, but there are few impressive 

 archaeological sites located in such sedi- 

 ments on this side of the Atlantic. After 

 World War II, when techniques began 

 to be developed for extracting pollen 

 from inorganic sediments like silt and 

 clay, American archaeologists became 

 more interested in the potential of the 

 method. Chicago Natural History Mu- 

 seum is among the first institutions in 

 the United States to apply the technique 

 of pollen analysis directly to archaeolog- 

 ical sites. Operating under a joint grant 

 from the Museum and the National Sci- 

 ence Foundation, the 1960 Southwestern 

 Archaeological Expedition began pollen 

 research in eastern Arizona and western 

 New Mexico last summer. 



As pollen analyst for the Southwestern 

 Expedition I spent a month at its head- 

 quarters near Vernon, Arizona, working 

 in close harmony with Dr. Paul S. Mar- 

 tin and Dr. John Rinaldo collecting sed- 

 iment samples from archaeological sites 

 that they had investigated for the Mu- 

 seum over the past twenty years. I then 

 utilized the facilities of the Geochronol- 

 ogy Laboratories of the University of 

 Arizona at Tucson to process the sam- 

 ples and extract the pollen. Since my 

 return to graduate work in the Depart- 

 ment of Anthropology at Southern Illi- 

 nois University, I have continued to work 

 on the problem of pollen analysis. 



The research program is still far from 

 complete, but results are already begin- 

 ning to be evident. The environment 

 under which the early inhabitants of the 

 Southwest lived is gradually becoming 

 known to us. We have discovered corn 

 pollen in pithouses that were built before 

 the time of Christ, which indicates that 

 these early peoples practiced agriculture. 

 We have evidence that the contempo- 



rary forests of pine and juniper which 

 are now extensive in western New Mex- 

 ico were not so vast 1500 years ago; and 

 that a certain area in eastern Arizona 

 which is now treeless was once forested. 

 And we have learned that the inhabi- 

 tants of one thirteenth-century site near 

 Springerville, Arizona, were forced to 

 change their economic pattern from agri- 

 culture to hunting, in the relatively short 

 period of 75 years. This alteration in 

 the economy of these people was per- 

 haps not the result of a drought, as for- 

 merly postulated, but of a change in the 

 seasonal pattern of rainfall. 



In support of this hypothesis, it was 

 discovered that when the pueblo was 

 first built its inhabitants obviously de- 

 pended a great deal upon corn agricul- 

 ture, for about 50 per cent of the pollen 

 found was of corn. The presence of 

 other pollen types also indicates that the 

 Indians were living near a swampy area 

 that would furnish plenty of water for 

 corn growing. However, the amount of 

 corn pollen found decreased, with the 



is difficult to understand how a drought 

 could make a river cut its bed more 

 deeply, since there would be less water 

 to do the cutting. More likely, there 

 was an increase in the number of torren- 

 tial summer rainstorms whose fast-rush- 

 ing run-off waters caused the river to 

 erode the sand and silt of the stream bed. 

 The corn crop, no longer semi-irrigated 

 by the easily diverted waters of the 

 swamp, became less dependable as a 

 food supply. 



How did the Indians respond to this 

 change? They could have moved away 

 from the area, but they did not. Per- 

 haps they thought they were having just 

 a run of bad luck and that good times 

 would return. In any case they filled 

 in their pueblo and constructed a new 

 pueblo on top of the old one, possibly 

 for religious reasons connected with the 

 reduced corn supply. But the pollen 

 from the new pueblo shows that the en- 

 vironment did not improve. After liv- 

 ing in their new home for a long time, 

 subsisting more and more on game and 



Author Schoemvetter at work in his laboratory at Southern Illinois University. 



passing of time, to five per cent of the 

 total, while the pollens of the swamp- 

 favoring cattail and sedges disappear 

 from the record and are replaced by 

 pollen from plants that indicate condi- 

 tions of sediment disturbance. Appar- 

 ently, the swamp was beginning to drain 

 away as the river which fed it cut its bed 

 deeper and lowered the water table. It 



wild foods, with an occasional successful 

 corn crop, they finally abandoned the 

 site and never returned. 



Thus these thirteenth-century Indians 

 reacted to climatic change by changing 

 their economy from agriculture to hunt- 

 ing while clinging to their home as long 

 as they could. What, I wonder, would 

 we do? 



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