Science and society SM 4

Domestication of Plants and Animals

  • Definition of Domestication:

    • The process of adapting wild plants and animals for human use.

    • Domestic species are raised for various purposes including food, work, clothing, and medicine.

    • These species require care and raising by humans, differentiating them from wild counterparts.

Plant Domestication

  • Origins:

    • Began approximately 10,000 years ago in Mesopotamia (modern countries: Iran, Iraq, Turkey, Syria).

    • Early humans collected and planted seeds of wild plants and ensured adequate water and sunlight for cultivation.

  • First Domesticated Plants:

    • Included wheat (Triticum aestivum), barley (Hordeum vulgare), lentils (Lens culinaris), and various peas.

    • Other civilizations, such as those in eastern Asia and the Americas, also domesticated plants like rice (Oryza sativa) and potatoes (Solanum tuberosum).

    • Additionally, plants were domesticated for non-food purposes, such as cotton for fiber and tulips for decorative uses.

Animal Domestication

  • Timeline:

    • Coincided with the domestication of plants in Mesopotamia.

    • Early domesticated animals provided meat, milk, and hides for clothing and shelter.

    • Goats were among the first domesticated animals, followed by sheep and chickens (approx. 10,000 years ago).

  • Larger Animals:

    • Gradually, humans began domesticating larger animals like oxen (Bos taurus) and horses (Equus ferus caballus) for labor.

  • Characteristics of Domesticable Animals:

    • Easiest to domesticate are herbivores grazing on vegetation, as they are simpler to feed.

    • Herbivores that eat grains (like chickens) are harder to domesticate due to the need for domesticated grains.

    • Some animals, such as dogs (Canis lupus familiaris), while originally used for specific purposes (like hunting), have evolved to serve as pets.

Selective Breeding of Domesticated Animals

  • Breeding Traits:

    • Historically, animals have been bred to enhance traits such as the ability to breed in captivity and calm temperament.

    • Resilience to diseases and adaptability to challenging climates are also sought-after traits.

  • Evolution from Wild Ancestors:

    • Domestication over millennia has significantly altered animal characteristics; for example, the size of domestic chickens has increased from about 0.9 kg (2 lbs) to as much as 7.7 kg (17 lbs).

    • Domestic chickens have a higher egg-laying capacity, averaging over 200 eggs annually compared to their wild ancestors.

Effects of Domestication on Humans

  • Agricultural Revolution:

    • Marked a significant turning point, leading to more sedentary and agriculturally-based lifestyles.

    • Reduced the necessity for nomadic lifestyles, allowing humans to settle near fields of domesticated plants.

  • Impact on Population:

    • Domestication has facilitated higher population densities due to stable and predictable food sources.

    • Development of the first villages and cities arose in fertile areas conducive to agriculture (e.g., floodplains).

  • Advancements in Tools:

    • The early adoption of farming tools began with stone implements leading to the development of metal tools, and eventually, animal-pulled plows.

Miscellaneous Facts

  • Dogs vs. Wolves:

    • Modern dogs are a distinct species from gray wolves (Canis lupus), as dogs are classified as Canis lupus familiaris.

  • Wild Horses and Training:

    • Domestication processes include training wild horses, a labor-intensive but essential task involving patience.