Mouthwatering Peruvian cuisine like causa (mashed yellow potatoes layered with avocado and seafood) and carapulcra (dried potatoes and pork/chicken in peanut sauce) combine food crops from Amazon basin rainforests and Andean highlands. Smithsonian archaeologists and colleagues presenting in the prestigious journal, Nature1, uncover the first definitive evidence for this culinary, cultural link: 3600-4000 year-old plant microfossils and starch grains.

Heading to the supermarket to pick up some corn flour, a couple of tomatoes or a can of beans usually doesn't conjure up the notion of 10,000 years of agricultural development in the Americas--a transition from hunter-gatherer cultures to agricultural cultures actively developing and trading new food crops. But this transition is still inadequately understood. New excavations and a growing collection of plant microfossil remains rapidly adds pieces to this puzzle.

A multidisciplinary team excavated a stone house at Waynuna, north of Arequipa on the western slope of the Andes and analyzed plant remains from three grinding stones.