Maize: Origin, Domestication, and its Role in the Development of Culture

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Maize: Origin, Domestication, and Its Role in the Development of Culture
Teosinte
In his 1893 study, Harshberger accurately described the area where annual teosinte
grows, as well as the archaeological zones where it grew in the wild state
(Wilkes, 1989: 446). It is, however, worth recalling that this plant was not
studied in depth until Wilkes (1967) published his monograph; since then many
scholars have taken up this subject. The study by Wilkes (op. cit.) is not only
the best one ever made of teosinte; it also presents a taxonomy that differs from
the previous one (as was seen in Chapter 1), and he separates maize as a species
different from teosinte, whereas Iltis and Doebley considered it at the subspecie
level, for they based their work only on the compatibility of crosses and not on
visible characters (Grobman, 2004: 430).
Teosinte is the closest relative of maize. It has the same number of chromosomes
(20), and these are similar to those of maize in their lengths and in
the position of their centromeres. Teosinte hybridizes easily with maize, and
first-generation hybrids are vigorous and highly fertile when self-pollinated or
when they are crossed back to either parent (Mangelsdorf, 1974: 15).
The first Latin name given to teosinte was that provided by Schräder (1833),
which only referred to the annual form – Euchlaena mexicana Schräder. In 1910
A. S. Hitchcock (1922) discovered the perennial form of teosinte, which he called
Euchlaena perennis Hitchcock. Kuntze (1904) and Reeves and Mangelsdorf
(1942) subsequently ascribed it to the Zea genus and renamed it Z. mexicana
(Schräder) Kuntze and Z. perennis (Hitchcock) Reeves and Mangelsdorf. 1
Randolph (1976), however, disagrees with teosinte being ascribed to the Zea
genus. He presented three tables (Randolph, op. cit.: 1 [324], 2 [325], and 3
[326]) with 23 major differences in plant characteristics as well as in environmental
responses between modern Zea and Euchlaena, which have enough taxonomical
import to distinguish the two genera. In a previous study (Randolph,
1972; 2 see Randolph, 1976: 325), Randolph posited that these are two different
genera. In tables IV and V, Randolph (1976: 330 and 331) shows 19 differences
between ancient maize and teosinte. If we gather the results obtained in the
analysis of both modern and archaeological specimens, there are 32 inheritable
differences between maize and teosinte.
Randolph acknowledges the fact that more studies and experiments are
required, but he goes against the hypothesis that teosinte is the progenitor of
maize (Randolph, 1976: 330). In this study Randolph presents a long list based
on characteristics of genetic and taxonomic significance, which can be applied
to both modern as well as archaeological maize, and which are in contrast with
the essential differences of both modern teosinte uncontaminated by maize and
1
2
For more data regarding this point and full bibliographical data, see Mangelsdorf (1974:
19–20) and Doebley (1990: esp. p. 7).
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