Diamond - 132-191

Cultivation of Wild Plants

Domestication Overview: The process of transforming wild plants into cultivated varieties is illustrated through the examples of strawberries and raspberries, where protective measures like nets and greenhouses were essential in achieving desired traits.
Variation in Wild Plants: Ancient farmers recognized differences among wild plants. Features such as berry size and nut bitterness were obvious, while seed dispersal and dormancy mechanisms remained unnoticed until modern botany. Early plant selection led to unconscious evolution from wild to cultivated species.
Artificial Selection: Darwin's work on domesticated plants began with artificial selection, focusing on how farmers developed varieties like gooseberries through selection of superior traits. This process serves as a model for understanding natural selection.

Civilization Development: As observed, some regions embraced agriculture while others, even fertile areas like California and temperate Australia, did not. Two main theories emerge to explain this:
- Problems with local peoples' acceptance of agriculture.
- Lack of suitable wild plants in certain areas.
Domestication of Mammals: Fewer large mammalian species exist (148) compared to plant species (200,000), and determining the suitability for domestication is simpler for mammals.

Scarcity of Domestication Candidates: Despite abundant wild flowering plants, very few—only a few hundred—are edible, with just a dozen contributing significantly to global food supplies. Notable crops include wheat, corn, rice, and potatoes.
Unexplained Domestication Failures: Instances exist where certain plants, domesticated elsewhere, were never cultivated by native peoples in regions with wild relatives. For example, sorghum was domesticated in the Sahel but not in Southern Africa despite its presence there.
Cultural vs. Biological Factors: Understanding the failures of local peoples to domesticate plants requires analyzing both social constraints and biological potentials of the local flora.

Three Regions: The Fertile Crescent as the early site of food production contrasts with New Guinea and Eastern United States, which developed limited crop ranges and failed to create complex sociopolitical structures:
- Fertile Crescent: Home to abundant wild plant ancestors, allowing rapid crop development and high-density human populations.
- New Guinea: Established agriculture without cereals and lacked large mammals suitable for domestication, limiting protein sources and agricultural potential.
- Eastern United States: Also lacked significant local domesticates and relied on growing wild resources, with limited advancements toward complex societies until the arrival of Mesoamerican crops.

Local Knowledge of Flora: Ethnobiology reveals that various indigenous peoples possess extensive knowledge of local wild flora and fauna, hinting that they likely recognized potential domesticates. Evidence from sites like Tell Abu Hureyra illustrates selective gathering of useful plants by early peoples.
Contextualized Responses: Low yields and nutritional shortcomings in local agriculture suggest that the choices of early agriculturists were based on conscious selection, even revealing an understanding of plant utility in terms of protein and calorie content.

Axis Orientation: The major axis orientations of continents—North-South for the Americas and East-West for Eurasia—played a critical role in the spread of agriculture, with the latter allowing easier diffusion of crops suited for similar latitudes.
Rapid Adoption: The Fertile Crescent's flora benefited from Mediterranean climate, and as agriculture spread, the rapid adoption of food production fostered advancements in technology and social complexity.
Curtailments of Spread: The slow spread of domestic crops along the Americas' North-South axis proves less favorable, as conditions varied significantly across small distances, inhibiting the transfer of agricultural knowledge and practices between regions.

Influential Factors: Key determinants for successful domestication and agricultural spread include:
- Preemptive domestication hindered by the abundance of potential crops already available in regions like the Fertile Crescent.
- The expansion of agricultural practices depends highly on shared climatic conditions and ease of transfer of knowledge.
- Biological constraints existed due to the differing number of viable domesticable species among continents, impacting the rate and complexity of agriculture.
Conclusion: The advantages for some areas over others often reflect their environmental characteristics and available flora and fauna, rather than cultural or intellectual superiority of their peoples.