The Neolithic Revolution narrative associates early-mid Holocene domestications with the development of agriculture that fueled the rise of late Holocene civilizations. This narrative continues to be influential, even though it has been deconstructed by archaeologists and geneticists in its homeland. To further disentangle domestication from reliance on food production systems, such as agriculture, we revisit definitions of domestication and food production systems, review the late Pleistocene–early Holocene archaeobotanical record, and quantify the use, management and domestication of Neotropical plants to provide insights about the past. Neotropical plant domestication relies on common human behaviors (selection, accumulation and caring) within agroecological systems that focus on individual plants, rather than populations—as is typical of agriculture. The early archaeobotanical record includes numerous perennial and annual species, many of which later became domesticated. Some of this evidence identifies dispersal with probable cultivation, suggesting incipient domestication by 10,000 years ago. Since the Pleistocene, more than 6500, 1206 and 6261 native plant species have been used in Mesoamerica, the Central Andes and lowland South America, respectively. At least 1555, 428 and 742 are managed outside and inside food production systems, and at least 1148, 428 and 600 are cultivated, respectively, suggesting at least incipient domestication. Full native domesticates are more numerous in Mesoamerica (251) than the Andes (124) and the lowlands (45). This synthesis reveals that domestication is more common in the Neotropics than previously recognized and started much earlier than reliance on food production systems. Hundreds of ethnic groups had, and some still have, alternative strategies that do involve domestication, although they do not rely principally on food production systems, such as agriculture.

Sabal palm has been used for thatching the traditional Maya house for over 3000 yr. The great importance of this resource has promoted its management within home gardens. Although traditionally managed populations in home gardens are capable of ecological long-term persistence, the impact of cultural change on sustainable resource management is poorly understood. By means of interviews in 108 households, we obtained information about Sabal management practices, leaf demand, and sociocultural data. Density and size structure of the palm populations in the respective home gardens were also measured. By means of principal components analysis, the sociocultural data were summarized into a cultural change index, which was then statistically related to palm density, size structure, leaf demand, and management practices. Leaf demand along the cultural change gradient was estimated. Sabal populations were affected by the cultural change index. Palm density and the proportion of harvestable individuals were higher in the more traditional households. The number of management practices decreased, and the probability of felling adult palms increased with cultural change. As a result, the percentage of the total leaf demand satisfied by home garden production diminished from 118.2-69.4% as cultural change increased. Traditional practices seem oriented to increasing the palm availability. Seed sowing and the protection of seedlings and adults affect the life stages with the largest impact on the population growth rate, as measured through sensitivity analysis. This means that abandoning traditional practices and felling adults more frequently should reduce rapidly, which is consistent with the low palm density observed in less traditional households. The application of demographic models to Sabal tells us that traditional management warrants the persistence of the resource as long as the current conditions remain unchanged. In contrast, our data show that Sabal management may not be sustainable from a cultural perspective, since the cultural attitudes that affect palm management and demand change over time. Both approaches assess the same problem from different viewpoints reaching different but complementary conclusions. In this study, we propose new methods that integrate the ecological and cultural processes, which affect the sustainable management of the natural resources.

Xa'an palm (Sabal yapa) has been used to thatch traditional Maya houses for over 3000 years. In the Yucatan Peninsula, this palm has been introduced to pasturelands, maize fields (milpas), and homegardens. These and other traditional management systems are usually believed to be sustainable, but there is as yet little evidence to support this hypothesis. Demographic models have been used for this purpose, mainly focusing on population growth rate (λ). So far, retrospective analysis has not been applied, even though it examines how changes in the the life cycle of a species, caused by different management regimes, affect its λ. In this study, we assess whether ecologically sustainable use of xa'an occurs in homegardens, pasturelands, and milpas, and if so, how it is achieved. We constructed matrix population models for four populations of xa'an that were followed for 3 years, and then conducted a retrospective analysis on them. Management in homegardens seems to be oriented to increasing the availability of xa'an leaves, favoring the survival of seedlings, and increasing the density of harvestable-sized palms. However, in the milpa and the pastureland, the population size structure resembles that of unmanaged populations. Our λ values suggest that the traditional use of xa'an in all the studied management regimes is sustainable. Nevertheless, the processes that lead to sustainable use are different in each system, as shown by our retrospective analysis. Although fecundity contributes positively to λ only in homegardens, permanence and growth maintain palm populations at an equilibrium in the pastureland and in the milpa, respectively. Between-year climatic differences had a smaller impact on λ than management practices, which may vary from one year to another, leading to different balances in the sustainable use of the populations involved. Even though no significant differences were found in λ values, Maya achieve sustainable use of xa'an palm under diverse scenarios by managing the great plasticity of the species, as was revealed by the retrospective analysis. Hence, this approach proved to be effective, not only for assessing sustainable use, but also for understanding the factors that favor or limit it.

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The Balsas River Basin (BRB) area is the major source of wild medicinal plants commercially sold in Mexico; thus, the region is important in the conservation of these high-demand resources. We studied wild medicinal plant species extracted from the BRB to document the species richness of traded plants and analyze the commercialization dynamics and socioecological vulnerability. We constructed a database of the medicinal plant species traded in the BRB and we developed a risk index from 14 different ethnobotanical, socioeconomic, and ecological variables to assess the vulnerability of each species. The medicinal flora that are traded in the BRB include 257 species, 176 genera, and 83 families. The use of 91% of these species is unregulated by the government. Tropical deciduous forests contribute the greatest number of taxa (38.5%) and herbs are the most harvested plants (45.9%). Less than 5% of these species are protected by national and international regulations. The highest-risk category primarily consists of tree species with the greatest number of uses and plant structures harvested and sold in the largest number of local and regional markets. Due to high commercial demand in the BRB, intensive harvesting is not compatible with conservation. Therefore, public policies that regulate trade and local practices to protect and preserve medicinal plant species must be developed. These policies should maintain people's livelihoods, especially in regions with high marginalization but great biological and cultural richness, such as the BRB.

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Commercial harvests can threaten tree species harvested for their bark. Amphipterygium adstringens is a dioecious tree, endemic to the tropical dry forests of Mexico, where it is intensively harvested for its medicinal bark. Limited information hinders developing sustainable management strategies for A. adstringens. We assessed bark regeneration for male and female trees, and evaluated the effect of tree sex and diameter, debarking treatments and cutting seasons on bark regeneration and tree survival rates. Bark regeneration was higher for wet season harvested trees (vs. dry), regardless of their sex. Bark regeneration was higher on female than on male trees. There were significant interactions of harvest season, harvest treatment and tree sex diameter on bark regeneration and survival. Overall, the highest bark regeneration rates occurred in female trees with ≥20.1 cm diameter that were wet season harvested with a 50% debarking intensity. Consequently, wet season and intermediate intensity harvests appear to foster sound management, but we recommend against targeting exclusively a single demographic group (i.e., large female trees) due to potential negative impacts on species demography and bark supply. A grounded strategy for sustaining bark harvest would also need to take into account relevant aspects of local socio-ecological context, including harvest interactions with other land uses.

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