
Show number 1209
- How do ethnobotanists discover which types of plants were growing thousands
of years ago and how people used them?
Peggy explores how the ancient Maya culture used corn.
Segment length: 8:39
Contents

Corn has always played an important role in the lives and culture of the Maya people.
In fact, the Maya creation story states that the flesh of humans came from sacred ears
of maiz. According to this story, the Creators saw people as a milpa, or cornfield,
ready to serve them.
But apart from information we can gather through Maya legends and traditions, how do we
know that corn was indeed an integral part of this culture and made up 80% of the Maya
diet thousands of years ago? To answer questions like this, many scientists, including
anthropologists, archaeologists, chemists, biologists, botanists, and ethnobotanists,
must work together.
Ethnobotanists are scientists who study the role of plants in a society. To better
understand how a particular culture interacted with plants in the past, ethnobotanists
look for clues in many places. They can learn a lot by finding out how an area's
current society uses plants.
When you visit the areas of Mexico and Central America populated by five million Maya
descendants, it's easy to see that corn continues to be the most important food in the
Maya diet. Maya cooks soak kernels of dried field corn in water and lime and then grind
the mixture with a mano and metate to make the thick zacan, just as their ancestors
have done for thousands of years. They pat the zacan into tortillas or fill it with
meat, fruit, or chiles, and then wrap it with corn husks or banana leaves and steam it
to make tamales. They even use ground corn to thicken atole, a drink often sweetened
with fruit or chocolate.
But ethnobotanists need to examine information from sources other than present-day
society. Paintings, carvings, figurines, and other art discovered at ancient Maya
temple ruins reveal that corn played an important role in religion as well as diet,
confirming that the Maya revered the maize god.
Since plants exposed to the elements decompose quickly, ethnobotanists also analyze
soil samples taken from archaeological sites. They look for pollen, charred seeds, or
food remains stuck in the bottom of broken pots. Then they study these fragile remains
to analyze the plant's DNA and to compare it with that of the plant's contemporary
descendants.
Ethnobotanists contribute much to our understanding of how the Maya have interacted
with the plants in their environment for thousands of years. These scientists can show
us how ancient customs translate into modern life and suggest methods to conserve the
traditional ways of a proud culture such as the Maya.
- What other peoples in the world rely on corn as a dietary staple?
- How important is corn in your own diet?
- Popped kernels of corn several hundred years old were discovered with
mummies buried in the ruins of a community in Paracas, Peru. What foods other than corn have been around
that long?
- Ask grandparents or friends how their diets have changed over the past 50
years.
chocolate a Mexican discovery, made from ground roasted cacao beans. Originally used to
make religious ritual drink offerings and as money.
ethnobotany study of human relationship to plants, often involving study of ancient
plant remains, oral history, written records, and myths
maiz Spanish word for maize, or corn
mano small, hand-held cylinder carved out of basaltic rock, used to grind corn in a
metate
metate container carved out of basaltic rock, used with a mano to grind corn for dough
tamale ground corn dough filled with meat, fruit, or chiles, then wrapped in corn
husks or banana leaves and cooked by steaming
tortilla flat, pancakelike food made from ground corn
and baked on a griddle over an open fire or on a stove
zacan thick dough used to make tortillas and tamales
- Amlin, P. (1994) Popul Vuh: The creation myth of the Maya (film).
Washington, DC: NEH.
- Coe, M. (1987) The Maya (4th ed., rev.). New York: Thames and Hudson.
- Hernandez, X., Ballonga, J. & Escofet, J. (1992) San Rafael: A Central
American city through the ages. Boston: Houghton Mifflin.
- Palazuelos, S., Tausend, M. & Urquiza, I. (1991) Mexico, the beautiful cookbook:
Authentic recipes from the regions of Mexico. San Francisco: Collins Publishers.
- Schele, L. & Miller, M.E. (1986) The blood of kings: Dynasty and ritual in Maya art.
Fort Worth: Kimball Art Museum.
- Stuart, G. & Stuart, G. (1983) The mysterious Maya. Washington, DC: National Geographic
Society.
- Tom Snyder Productions videodisc: The Maya: Ancient Skywatchers. The Great Solar System
Rescue (side 2, frames 36132-41383). Check for it in your video library.
- Trout, L.H. (1991) The Maya. New York: Chelsea House Publishers.
Community resources
Local natural history museum
Local Maya studies group
Mexican restaurants

Ethnobotanists make many discoveries by studying soil samples. As you work through
several rounds of soil and water separation, try to imagine that you are working at an
archaeological site and that your findings could reveal the way people lived and ate
thousands of years ago.
Materials
- notebook for observations
- pencil
- clear plastic 2-cup containers with lids
- water
- bag of soil--allow about 1 kg (2.2 lbs) per person
- 1 paint tray per person (the kind used with roller brushes)
- about 1 cup each of dried corn, dried green and yellow peas, lentils, rice, and beans
- flower seeds
- grass seeds
- pepper
- sand
- glitter
- paper towels, coffee filters, cheesecloth, or screen material
- Work in teams to create at least six different mixtures to analyze. They
might include combinations of soil and grains, sand and glitter, pepper and grains, grass
seeds and soil, etc. Try to include different weights.
- Place each mixture in a different container and secure the lid. Label each mixture
with a letter or number that doesn't reveal the contents. Keep track of the contents of
each mixture in your notebook.
3. Trade mixtures with another team. Your goal will be to determine the contents of
the mixture in each jar.
- Shake each container well. Remove the lid and check the mixture. Has anything moved
to the bottom or top of container? Record your observations.
- Add enough water to make a soup the consistency of broth. Secure the lid and shake
well.
- Pour each mixture into a paint pan. Heavier matter in the mixture should filter out
of the liquid and remain at the higher level in the pan. Liquids should flow to the
deeper end of the pan and lighter matter should float on top of the liquid. Use paper
towels, cheesecloth, or a screen to filter the liquid into another container. What's
left in the filter? What's left in the liquid? Record your observations.
- After you have repeated this process of separation for each mixture prepared by the
other team, draw conclusions about the contents of each mixture. Ask the other team to
check your findings.
- Now that you've tried this activity indoors with mixtures you created, take your
ethnobotany skills outside and collect real soil samples. Determine what methods of
soil separation to use and record your findings.

Questions
- How does soil and water separation work? Can you think of substances that
could not be separated using water?
- Ethnobotanists use soil separation in their research. What other
scientists use this process as well?

TRY THIS!
Look at pictures of Maya art. Look for representations of corn and other plants. Create
a clay figure or a drawing that represents foods most important in your own
culture.

TRY THIS!
How much do you know about the ethnic groups that live in your community? Visit a large
grocery store and list as many products as possible that come from other countries.
Visit local ethnic markets and note which plant foods seem to be most prevalent.
Talk to the store owner about how the foods are prepared. You may need to ask someone
in the store to translate the labels for you.

TRY THIS!
The ancient Maya numeration system used base 20, unlike the Hindu-Arabic system which
uses base 10. Research the Maya numeration system, as well as other systems, and
compare them with the system you use. Two good references are Multicultural Math
Posters from Kay Curriculum Press [(800) 338-7638] and Multicultural Mathematics
Posters and Activities from the National Council of Teachers of Mathematics [(800)
235-7566].
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