The analysis shows the oldest remains were people who ate wild plants, palms, fruits and nuts found in tropical forests and savannahs, along with meat from hunting terrestrial animals.
By 4, years ago, diets had become more diverse, with some individuals showing the first consumption of maize. The isotopic signature of two young nursing infants shows that their mothers were consuming substantial amounts of maize. The results show an increasing consumption of maize over the next millennium as the population transitioned to sedentary farming.
Prufer noted, "We can directly observe in isotopes of bone how maize became a staple grain in the early populations we are studying. We know that people had been experimenting with the wild ancestor of maize, teosintle, and with the earliest early maize for thousands of years, but it does not appear to have been a staple grain until about BP.
After that, people never stopped eating corn, leading it to become perhaps the most important food crop in the Americas, and then in the world. Excavations were directed by Prufer along with an international team of archaeologists, biologists, ecologists and geologists. Numerous UNM graduate and undergraduate students took part in the field research as well as collaborators with the protected area co-management team, a Belizean NGO the Ya'axche' Conservation Trust.
Conditions weren't easy for the excavation teams, Prufer noted: "We did five years of fieldwork in two very remote rock shelter sites in the Bladen Nature Reserve in the Maya Mountains of Belize, a vast wilderness area that is a two-day walk from the nearest road. To work in this area we had to camp with no electricity, running water, or even cell service for a month at a time each year.
We already have a Ph. Materials provided by University of New Mexico. Original written by Mary Beth King. Note: Content may be edited for style and length.
Science News. Related Multimedia : YouTube video: When did people start eating corn? Journal Reference : Douglas J. Kennett, Keith M. Prufer, Brendan J. Culleton, Richard J. George, Mark Robinson, Willa R. By the time the cobs ended up on the floor of the ancient cave, maize had already travelled far beyond Mexico, and had been cultivated in the southwest Amazon for around 1, years.
So, Kistler and his fellow researchers decided to take a closer look at corn DNA—and what they found suggests that while the domestication of teosinte did indeed begin in Mexico,. The new study analyzed the genomes of more than varieties of modern maize, around 40 of which were sequenced by the researchers. The team also looked at the DNA of 11 ancient plants. When they mapped out the genetic connections between the specimens, the researchers discovered several distinct lineages, each with their own unique relationship to teosinte.
Most significantly, the results revealed that although maize domestication began with a single large gene pool in Mexico, the grain was carried elsewhere before the domestication process was complete. The partially domesticated maize seems to have landed in the southwest Amazon, which was already a hotspot for the domestication of other plants, including rice, squash and cassava. Kistler theorizes that maize was adopted into farming practices there, giving the domestication process a chance to pick up where it left off.
It is possible, though not certain, that maize in this new location evolved more quickly than maize in the center of domestication, which would explain why the 5,year-old cobs from the cave in Mexico appear to be in an intermediary phase of domestication at a time when maize was already being cultivated in the Amazon. Early farmers in Mexico domesticated Teosinte by selecting the biggest and best kernels until the crop we recognise today as maize was arrived at.
Maize spread fast because it was nutritious, easy to grow, easy to store and easy to carry. Domesticated maize initially spread south down the coast to Peru and beyond, as well as across the North Americas, until eventually Native Americans continent-wide had adopted it as a vital part of their diet. Before long, it was a staple food across most cultures in North and South America and the Caribbean.
It was during this period that maize, along with three other crops that were subsequently to become vital staples in the Old World — potatoes, sweet potatoes and cassava — were brought to Europe. As well as these staples, a range of other foods came too, such as peanuts and pineapples and cocoa beans chilli peppers.
La Santa Trinidad — a Spanish galleon. Earlier versions of such ships were used by the first European voyagers to reach the Americas. When Europeans arrived in the Americas, maize was already being grown from Canada to Chile, although interestingly, very little was grown in the plains and savannahs of the central US and northern Argentina, areas which today are amongst the most productive agricultural areas in the world.
This was because Native Americans practised slash and burn agriculture — which was not suitable for grassy areas. Although maize has long been a significant crop on the European continent, it only became significant in the UK relatively recently, where it is mainly grown as food for livestock, and as game cover. Additionally, in recent decades the increasing trend for green power has driven farmers to use it as an energy crop for anaerobic digesters.
The amount of maize grown in the UK has rocketed since the s. In there was around 20, acres of maize being farmed in Britain, by this had reached , acres.
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