Archaeological evidence suggests that the agricultural practices of animal and plant domestication spread globally between 10,000 and 2,000 BCE. In A History of World Agriculture: From the Neolithic Age to the Current Crisis, Marcel Mazoyer and Laurence Roudart hypothesize that agriculture originated in the Middle East, providing evidence from archaeological sites in Iraq, Israel, Jordan, Lebanon, Syria, and Turkey. Mark Tauger supports this hypothesis in Agriculture in World History, and indicates that the earliest agricultural practices entailed setting aside land for resident animals to graze and for growing indigenous edible plants.
In Seed to Civilization: The Story of Food, Charles Heiser discusses many aspects of crop development, and mentions that wild grains were likely the first plants cultivated as crops for personal use and for commerce. Successes with growing grains led to the cultivation of nutrient-rich plants such as legumes. In terms of animals, Heiser explains that by around 8,400 BCE, goats, pigs, and sheep most likely became the first domesticated animals because they were believed to congregate around human settlements. Cattle, corralled around 6,500 BCE, were initially a source of meat and were later used for milk by some cultures.
One of the writings in Thomas Garnett’s Essays in Natural History and Agriculture discusses how throughout the Neolithic period of agriculture, people developed selective breeding practices by growing only those animals and crops with desirable characteristics. Selective breeding led to improved food production, and it increased the diversity of animals and plants used in agriculture. The practice of selective breeding became the hallmark of agriculture and remained relatively unchanged until Gregor Mendel, a monk in an area now part of the Czech Republic, explained the rules of heredity in the 1850s. In actuality, Mendel’s work remained obscure until the early 1900s when geneticists Hugo de Vries and Carl Correns rediscovered his findings.
In A History of Farming Systems Research, edited by M. Collinson, international contributors describe the directions agricultural research has taken based on balancing current technology and societal needs for an expanded food supply. The book mentions genetics as one driving factor in agricultural developments. For example, the ability to accurately predict the inheritance of traits greatly improved the effectiveness and precision of selective breeding. Further breeding advances came about with the discovery of genes and gene function in the 1960s and 1970s. However, the greatest agricultural revolution was realized when researchers discovered in the 1970s and 1980s that the inherited material could be predictably altered through genetic modification. Genetic modification made selective breeding all but obsolete, paving the way for modern agricultural biotechnology.
Modern agricultural biotechnology involves a large variety of techniques for altering the properties of animals, fungi, and plants. In A Revolution Down on the Farm: The Transformation of American Agriculture since 1929, Paul Conkin describes how a series of agricultural paradigm shifts driven by new social needs fueled advances in agricultural biotechnology. The book explains that there are now many genetic modification techniques that change the properties of an organism’s DNA. These new technologies permit the introduction of artificial genes made from several types of organisms into an unrelated organism. Cell components can also be modified to produce novel characteristics. Older agricultural practices such as grafting for asexual propagation have now been replaced by the production of chimeras and clones. Cloning routinely produces many copies of a plant much better than standard propagation from cuttings. Chimeras, which are mixtures of two genetically different organisms, can produce a dual-purpose organism more much accurately and consistently than grafting.
A History of world agriculture: From the neolithic age to current crisis by 
A Revolution down on the farm: The Transformation of American agriculture since 1929 by 
