Short answers, pulled from the story.
Domestication is a multi-generational mutualistic relationship in which one species takes over the control and care of another to obtain a steady supply of resources such as meat, milk, or labor. The process is gradual and geographically diffuse, based on trial and error. It affects genes for behavior in animals and genes for morphology in plants, such as increasing seed size and stopping the shattering of cereal seedheads.
The dog was the first animal domesticated by humans, as a commensal, at least 15,000 years ago. It became established across Eurasia before the end of the Late Pleistocene, well before agriculture, and unlike later domesticates it was initially selected for its behaviors rather than production traits.
Plant domestication began around 13,000 to 11,000 years ago with cereals such as wheat and barley in the Middle East, alongside lentil, pea, chickpea, and flax. Rice was first domesticated in China some 9,000 years ago, while peanuts, squash, maize, potatoes, cotton, and cassava were domesticated in the Americas.
At least three groups of insects, namely ambrosia beetles, leafcutter ants, and fungus-growing termites, have independently domesticated species of fungi on which they feed. The domestication of fungi by Atta leafcutter ants took 30 million years, while fungus-growing termites of the subfamily Macrotermitinae cultivate Termitomyces fungi in a relationship that began exactly once, 25 to 40 million years ago.
The domestication syndrome is the suite of phenotypic traits that distinguish domesticated species from their wild ancestors. In mammals it includes increased docility and tameness, coat coloration changes, reductions in tooth and brain size, floppy ears, altered craniofacial morphology and estrus cycles, and prolonged juvenile behavior.
Domestication produced zoonotic diseases, with cattle giving humanity poxes, measles, and tuberculosis, pigs and ducks contributing influenza, and horses bringing rhinoviruses. It also reduced the genetic diversity of domesticated populations, and scholars such as Murray Bookchin and David Nibert have argued it altered humanity itself and enabled social hierarchy, conquest, and exploitation.