ENVIRONMENTAL ARCHEOLOGY AND ETHNOBIOLOGY

HUMAN RESPONSES TO ENVIRONMENTAL CHANGE

1. MOVE
   
   • Anasazi move out of Canyon de Chelly valley bottoms during wet periods (Betancourt and Davis, 1984)
     
   • From Plains to Mountains during Altithermal (Benedict, 1979) Altithermal Migration
     
     
   • To higher elevation, AD 800-900, Dolores, Colorado (Petersen, 1988)
     
   • To marginal habitats during Pueblo Period (coincides with the Medieval Warm Period A.D. 1000-1300; Dean, Euler et al., 1985; Petersen, 1988)
     
     
   
   
2. ADAPT
   
   • Effect of Plant Immigration (Utilization to new resource)
     
     • Western Red Cedar and People (Hebda and Mathewes, 1984) Late Holocene (<3500 yr B.P.) increase in the Pacific NW
       
       
     • Pinyon Pine: Holocene Migration into central Great Basin? Present in N. Great Basin 7410±120 yr B.P. @ Danger Cave (Madsen, Rhode, 1990)
       
   • Resource Managment: irrigation
     Tucson Basin canals 4000 yr BP
     Dolores, Colorado AD 800-900 (canals at low elevation; Petersen, 1988)
     Hohokam canals, Phoenix Basin, (Masse, 1981)
     
   • Resource Depletion: Importance of local fuel (Chaco Canyon, Betancourt and Van Devender, 1981; Hay Hollow, Hevley, 1981)
     Easter Island Deforested 1200-800 yr B.P. (Finley et al., 1991)
     
     
     
3. PERISH
   
   • Collapse of civilizations following prolonged drought
     Akkadian (4.2 Ka), Moche (500 AD) and Mayan (900 AD) (deMenocal, 2001; Hodell et al. 2001)
   • Get sick and die in California (Raab, 1994)
     
     

• 1750 - 1250 ya (A.D. 200-700) founding of 11 of 16 sites
  
• 1250 - 900 ya (A.D. 700-1050) rapid growth in 17 of 20 sites
  
• 900 - 650 ya (A.D. 1050-1300) maxima for 19 of 27 sites = MWP
  
• 650 ya (A.D. 1300) abandonment
  


• Moisture Maxima
  • 1300 - 1250 years ago (A.D. 650-700) Basketmaker III
    
  • 1000 - 800 ya (A.D. 950 - 1150) greater density
    
    
  
  
• Moisture Minima
  • Little Ice Age Drought
  • Great Drought A.D. 1275-1300: site abandonment, construction of irrigation devices, concentration of populations along rivers
    
    

Effects of Human Activities on the Environment

• Global Effects: lead in polar ice cores (Hong et al., 1994)
  
  
• Fire: human-caused fires determined position of prairie-forest border Grimm (1983)
  
• Reduced native vegetation (Hevley, 1981; Betancourt and Van Devender, 1981)
  
• Increased weed frequency (McAndrews, 1988; Fish, 1985))
  
  • Arizona Chenopodiaceae, Tidestromia, Sphaeralcea, Borehaavia
    
  • California Compositae
    
  • SE Washington: Compositae followed by Chenopodiaceae
    
  • Midwestern U.S.: Ambrosia
    

SOURCES OF ARCHAEOBOTANICAL INFORMATION

• Pollen
  • Room Function: food processing, storage, use areas
  • Diet: coprolites, metates, storage cysts
  • Human Impact: weeds, fire
  • Construction (adobe): age, season, source of mud
  • Artifact Sourcing: "pollen-washes" palynomorphs in chert
• Seeds
  • processed by "Flotation" Emil Haury, 1964 Snaketown
• Phytoliths plant utilization, environment
• Bone archeozoology, environment
• Wood (charcoal) identification: sturctures, fuel resources
• Sand temper in pottery (Dye and Dickinson, 1996)
• Termite Feces: fuel resources, environment

Utilization (19,500 ¹⁴C yr B.P.; Piperno et al, 2004) vs. Domestication

Domestication

Squash 10,000 ya Corn (7) 6000 ya Sunflower 5000 ya Beans 2100 ya Cotton 1300 ya Amaranth 700 ya Chenopods ??



"Encouraged weeds"
• Purslane (Portulaca oleracea)
  wherever corn grown in North America
  
• Bee Weed (Cleome)
  Anasazi, Southwest

• Biogeography
  • native vs. introduced plants
    (Chapman et al., Byrne & McAndrews, 1975; 1974, Betancourt et al., 1984; Asch and Asch, 1977)
    
• prehistoric distribution of weeds (Bohrer, 1978)
• Effects of man on environment
  • over-exploitation of resources