1. From Teosinte to Maize A Genetic Journey

2. Scientific name: Zea mays spp. parviglumis

3. How did we get from this… www.historyforkids.org/learn/food/corn

4. To this….? http://soilcrop.tamu.edu/photogallery/cornsorghum+/images/corn%20ears.jpg

5. A significant difference http://www.nsf.gov/news/mmg/media/images/corn-and-teosinte_h1.jpg

6. Morphological Differences Between Maize and Teosinte Maize: rigid, 3-12 ranked rachis with solidly attached grains  grains require human intervention for dispersal and propagation. Rachis segments bear pairs of grain bearing spikelets oriented perpendicular to rachis axis. Open fruit case

7. Cont. Morphological Differences Teosinte: Two-ranked rachis that naturally disarticulates. Single grain-bearing spikelet per rachis, oriented parallel to rachis axis. Grains are protected inside closed fruit case.

8. Comparison http://teosinte.wisc.edu/morphology.html

9. Which traits were chosen? Early “farmers” did not want seeds to fall off easily. So they chose those individuals that had very attached seeds. They wanted many seeds per ear.  chose those with mutations having several rows and ranks. They wanted big seeds  chose individuals with the largest seeds.

10. When and where did it begin? Earliest evidence of cultivation 6,250 years B.P. Earliest evidence found in Guila ‘ Naquitz, Oaxaca Mexico Earliest cultivators: Pre-ceramic hunter- gatherers using cave shelters.

11. Photograph of three Guilá Naquitz archaeological cobs. Benz B F PNAS 2001;98:2104-2106 ©2001 by The National Academy of Sciences

12. Cultural Significance of Maize Project http://tvnoticias.files.wordpress.com/2008/04/m aiz.jpg -Pair up for this project -Use the internet to complete your research -You will have three class periods to work on this -Compile your findings into a power point presentation -Be prepared to present your project! -Follow your rubric closely!

13. References Benz, Bruce, F. (2001). Archaeological evidence of teosinte domestication from Guila’ Naquitz, Oaxaca. The National Academy of Sciences. Retrieved from http://www.pnas.org/content/98/4/2104.full on 9/3/2010.http://www.pnas.org/content/98/4/2104.full http://www.koshland-science-museum.org/exhibitdna/crops02.jsp http://teosinte.wisc.edu/morphology.html