Studies in Archaeological Maize I: The “Wild” Maize from San Marcos Cave Reexamined

1990 ◽  
Vol 55 (3) ◽  
pp. 500-511 ◽  
Author(s):  
Bruce F. Benz ◽  
Hugh H. Iltis
Keyword(s):  
Statistical Analysis ◽  
Morphological Similarity ◽  
Tehuacán Valley ◽  
Statistical Comparison ◽  
Tehuacan Valley ◽  
San Marcos ◽  
Cursory Examination ◽  
Mexican Maize

Cobs of the earliest known archaeological maize from San Marcos Cave in the Tehuacan Valley were reexamined to estimate their morphological similarity to extant Mexican maize races. Cursory examination of these 7,000-year-old specimens aroused suspicion that they are not very closely related morphologically to any thus-far-described modern Mexican race. Statistical comparison of the Tehuacan specimens with 30 races of Mexican maize fully confirmed this suspicion. However, the inclusion in our statistical analysis of an extant race of popcorn from Argentina morphologically similar to the Tehuacan specimens indicated that the two were virtually indistinguishable. These findings imply that the earliest maize from Tehuacan already was fully domesticated, its cobs exhibiting a morphology one would expect had maize evolved from teosinte by way of catastrophic sexual transmutation (Iltis 1983).

AMS Dates of New Maize Specimens Found in Rock Shelters of the Tehuacan Valley

Radiocarbon ◽  
2018 ◽  
Vol 60 (3) ◽  
pp. 975-987
Author(s):  
Esperanza Torres-Rodríguez ◽  
Miguel Vallebueno-Estrada ◽  
Javier Martínez González ◽  
Angel García Cook ◽  
Rafael Montiel ◽  
...  
Keyword(s):  
Archaeological Sites ◽  
American Continent ◽  
Large Collection ◽  
Tehuacán Valley ◽  
Global Comparison ◽  
Tehuacan Valley ◽  
San Marcos ◽  
Southeastern Region ◽  
Ams Dates ◽  
Rock Shelters

ABSTRACTA large collection of maize macro-specimens has been gathered from archaeological sites across the American continent, but only a few have been directly dated by accelerator mass spectrometry (AMS). We recently conducted two new excavations in several rock shelters of Tehuacán valley (San Marcos, Coxcatlán, and Purrón) and uncovered 132 non-manipulated macro-specimens of maize suitable for morphological and paleogenomic analysis, including many complete cobs, stalks, internodes, and leaves. Direct AMS dates for 43 samples found in San Marcos or Coxcatlán confirm the previously reported chronologies for these sites. By contrast, a cob found in Purrón was dated to 3060±30 before present (3360–3180 cal BP) (2σ), demonstrating that maize was present at that site at least 1500 calendar years earlier than previously expected, and suggesting that other specimens of similar age are still likely to be found in the southeastern region of the Tehuacán valley. A global comparison of macro-specimen chronology across the continent shows that the current archaebotanical record does not yet reflect the chronology of dispersal from central Mexico to northern or southern regions, opening the possibility for finding the missing links in subsequent expeditions within Mexico and Central America.

scholarly journals New AMS Radiocarbon Ages from the Preceramic Levels of Coxcatlan Cave, Puebla, Mexico: A Pleistocene Occupation of the Tehuacan Valley?

2021 ◽  
pp. 1-15
Author(s):  
Andrew D. Somerville ◽  
Isabel Casar ◽  
Joaquín Arroyo-Cabrales
Keyword(s):  
Mass Spectrometry ◽  
Last Glacial Maximum ◽  
Food Production ◽  
Tehuacán Valley ◽  
Rock Shelter ◽  
Last Glacial ◽  
Tehuacan Valley ◽  
Peopling Of The Americas ◽  
The Last Glacial Maximum ◽  
The Last Glacial

Archaeological studies at Coxcatlan Cave in the Tehuacan Valley of southern Puebla, Mexico, have been instrumental to the development of the chronology for the region and for our understanding of the origins of food production in the Americas. This article refines the Preceramic chronology of the Tehuacan Valley by presenting 14 new accelerated mass spectrometry (AMS) radiocarbon ages from faunal bone samples uncovered from early depositional levels of the rock shelter. Although bones associated with the El Riego (9893–7838 cal BP), Coxcatlan (7838–6375 cal BP), and Abejas (6375–4545 cal BP) phase zones of the cave yielded ages similar to those of the previously proposed chronology for the region, bones from the Ajuereado phase zones at the base of the cave yielded surprisingly old ages that range from 33,448 to 28,279 cal BP, a time prior to the Last Glacial Maximum. Because these early ages are many thousands of years older than current models estimate for the peopling of the Americas, they require reassessments of the artifacts and ecofacts excavated from these early zones.

Dr. Arnaud Replies

PEDIATRICS ◽  
1977 ◽  
Vol 60 (5) ◽  
pp. 761-761
Author(s):  
Sara B. Arnaud
Keyword(s):  
Vitamin D ◽  
Statistical Analysis ◽  
Vitamin D Deficiency ◽  
Statistical Comparison ◽  
Hydroxyvitamin D ◽  
Number Of Patients ◽  
25 Hydroxyvitamin D ◽  
Deficiency Rickets ◽  
Student’S T ◽  
Student’S T Test

Drs. Giangiacomo and Gleason are quite correct in their criticism that the number of patients with vitamin D deficiency rickets is too small for statistical comparison of the concentration of serum 25-hydroxyvitamin D (25-OH-D) in mild, moderate, and severe rickets. For this reason, we did not attempt this type of statistical comparison (Student's t test). The statistical analysis which supports our conclusion is the calculation of the regression between senim 25-OH-D, ng/ml and the stage of the disease, designated by arbitrary numbers 1, 2, and 3 for mild, moderate, and severe.

Ecological Status of Beaucarnea gracilis , an Endemic Species of the Semiarid Tehuacán Valley, México

1997 ◽  
Vol 11 (2) ◽  
pp. 367-374 ◽  
Author(s):  
Yuria Cardel ◽  
Victor Rico-Gray ◽  
José G. García-Franco ◽  
Leonard B. Thien
Keyword(s):  
Endemic Species ◽  
Ecological Status ◽  
Tehuacán Valley ◽  
Tehuacan Valley

Biotic interactions and the population dynamics of the long-lived columnar cactus Neobuxbaumia tetetzo in the Tehuacán Valley, Mexico

1999 ◽  
Vol 77 (2) ◽  
pp. 203-208 ◽  
Author(s):  
Héctor Godínez-Alvarez ◽  
Alfonso Valiente-Banuet ◽  
Leopoldo Valiente Banuet
Keyword(s):  
Population Dynamics ◽  
Matrix Models ◽  
Biotic Interactions ◽  
Positive Interactions ◽  
Elasticity Analysis ◽  
Finite Rate ◽  
Tehuacán Valley ◽  
Columnar Cactus ◽  
Tehuacan Valley ◽  
Rate Of Increase

The giant columnar cactus Neobuxbaumia tetetzo (Coulter) Backeberg is the dominant species of a vegetation type locally called "tetechera" that occupies ca. 400 km2 in the Tehuacán Valley. As a way to analyse the role of biotic interactions on the population dynamics of this species, we conducted an elasticity analysis, using matrix models elaborated from field data, to determine the finite rate of increase and the critical stages of the life cycle that were related to the biotic interactions occurring during these stages. Although the estimated finite rate of increase did not differ from unity there were significant differences between the actual and predicted size distributions. Elasticity analysis showed that survivorship was the most important life-history parameter to the finite rate of increase. Because survivorship depends on the presence of nurse plants, our results emphasise the importance of positive interactions on the population dynamics of long-lived columnar cacti.Key words: biotic interactions, Cactaceae, deserts, matrix models, population dynamics.

Pollination biology of the hemiepiphytic cactus Hylocereus undatus in the Tehuacán Valley, Mexico

2007 ◽  
Vol 68 (1) ◽  
pp. 1-8 ◽  
Author(s):  
A. Valiente-Banuet ◽  
R. Santos Gally ◽  
M.C. Arizmendi ◽  
A. Casas
Keyword(s):  
Pollination Biology ◽  
Tehuacán Valley ◽  
Tehuacan Valley ◽  
Hylocereus Undatus
Sign in / Sign up

Export Citation Format

Share Document