From the Archaic period onward, Indigenous populations across the Eastern Woodlands cultivated a suite of crops known to archaeologists as the Eastern Agricultural Complex. However, aside from squash (Cucurbita pepo) and sunflower (Helianthus annuus), little evidence exists for the cultivation of these plants in the northeastern Algonquian homeland. Botanical analysis from the Manna site (36Pi4), located in the Upper Delaware Valley, provides evidence for the cultivation of the full suite of Eastern Agricultural Complex crops. Flotation samples analyzed from Manna provide the first evidence for possible Lenape cultivation of chenopodium (Chenopodium berlandieri), squash, sunflower, and marshelder (Iva annua) from contexts dating to AD 0–1650 (Middle and Late Woodland) at Manna. Lenape cultivation of these crops complicates the traditional view of Indigenous agricultural systems in northeastern North America and raises questions about when and how these species were introduced to the region.

In eastern North America, Indigenous peoples domesticated several crops that are now extinct. We present experimental data that alters our understanding of the domestication of one of these—goosefoot (Chenopodium berlandieri). Ancient domesticated goosefoot has been recognized on the basis of seed morphology, especially a decrease in the thickness of the seed coat (testa). Nondomesticated goosefoot also sometimes produces seeds that look similar or even identical to domesticated ones, but researchers believed that such seeds were rare (1%–3%). We conducted a common garden experiment and a series of carbonization experiments to better understand the determinants of seed polymorphism in archaeobotanical assemblages. We found that goosefoot produces much higher percentages of thin-testa seeds (mean 50% in our experiment, 15%–34% in free-living parent populations) than previously reported. We also found that cultivated plants produce more thin-testa seeds than their free-living parents, demonstrating that this trait is plastic in response to a garden environment. The carbonization experiments suggest that thin-testa seeds preserve under a larger window of conditions than thick-testa seeds, contrary to our expectations. These results suggest that (1) carbonized, phenotypically mixed assemblages should be interpreted cautiously, and (2) developmental plasticity and genetic assimilation played a role in the domestication of goosefoot.

Recently, researchers investigating the origins of domestication have debated the significance of resource intensification in the shift from foraging to food production. In eastern North America, one of several independent centers of domestication, this question remains open. To determine whether initial domestication may have been preceded by intensification in eastern North America at approximately 5000 cal BP, I evaluated the archaeofaunal assemblages from six sites in the middle Tennessee River valley. Analyses of these data suggest that overall foraging efficiency gradually declined prior to initial domestication, but patch-specific declines in foraging efficiency occurred in wetland habitats and not terrestrial ones. Climatic warming and drying during the Middle Holocene, growing human populations, and oak-hickory forest expansion were the likely drivers of these changes in foraging efficiency. These results support the hypothesis that initial domestication in eastern North America was an outcome of intensification driven by environmental change and human population increases. Finally, while the debate concerning the relationship of intensification to domestication has been framed in terms of a conflict between niche construction theory and optimal foraging theory, these perspectives are compatible and should be integrated to understand domestication more fully.