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Agriculture

Agriculture encompasses crop and livestock production, aquaculture, fisheries, and forestry for food and non-food products. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to live in cities. While humans started gathering grains at least 105,000 years ago, nascent farmers only began planting them around 11,500 years ago. Sheep, goats, pigs, and cattle were domesticated around 10,000 years ago. Plants were independently cultivated in at least 11 regions of the world. In the 20th century, industrial agriculture based on large-scale monocultures came to dominate agricultural output.

, small farms produce about one-third of the world's food, but large farms are prevalent. The largest 1% of farms in the world are greater than 50 hectare and operate more than 70% of the world's farmland. Nearly 40% of agricultural land is found on farms larger than 1,000 hectare. However, five of every six farms in the world consist of fewer than 2 hectare, and take up only around 12% of all agricultural land. Farms and farming greatly influence rural economics and greatly shape rural society, effecting both the direct agricultural workforce and broader businesses that support the farms and farming populations.

The major agricultural products can be broadly grouped into foods, fibers, fuels, and raw materials (such as rubber). Food classes include cereals (grains), vegetables, fruits, cooking oils, meat, milk, eggs, and fungi. Global agricultural production amounts to approximately 11 billion tonnes of food, 32 million tonnes of natural fibres and 4 billion m3 of wood. However, around 14% of the world's food is lost from production before reaching the retail level.

Modern agronomy, plant breeding, agrochemicals such as pesticides and fertilizers, and technological developments have sharply increased crop yields, but also contributed to ecological and environmental damage. Selective breeding and modern practices in animal husbandry have similarly increased the output of meat, but have raised concerns about animal welfare and environmental damage. Environmental issues include contributions to climate change, depletion of aquifers, deforestation, antibiotic resistance, and other agricultural pollution. Agriculture is both a cause of and sensitive to environmental degradation, such as biodiversity loss, desertification, soil degradation, and climate change, all of which can cause decreases in crop yield. Genetically modified organisms are widely used, although some countries ban them.

Etymology and scope
The word agriculture is a late Middle English adaptation of Latin agricultūra, from ager 'field' and cultūra 'cultivation' or 'growing'. While agriculture usually refers to human activities, certain species of ant, termite and beetle have been cultivating crops for up to 60 million years. Agriculture is defined with varying scopes, in its broadest sense using natural resources to "produce commodities which maintain life, including food, fiber, forest products, horticultural crops, and their related services". Thus defined, it includes arable farming, horticulture, animal husbandry and forestry, but horticulture and forestry are in practice often excluded. It may also be broadly decomposed into plant agriculture, which concerns the cultivation of useful plants, and animal agriculture, the production of agricultural animals.

Origins
The development of agriculture enabled the human population to grow many times larger than could be sustained by hunting and gathering. Agriculture began independently in different parts of the globe, and included a diverse range of taxa, in at least 11 separate centers of origin. Wild grains were collected and eaten from at least 105,000 years ago. In the Paleolithic Levant, 23,000 years ago, cereals cultivation of emmer, barley, and oats has been observed near the sea of Galilee. Rice was domesticated in China between 11,500 and 6,200 BC with the earliest known cultivation from 5,700 BC, followed by mung, soy and azuki beans. Sheep were domesticated in Mesopotamia between 13,000 and 11,000 years ago. Cattle were domesticated from the wild aurochs in the areas of modern Turkey and Pakistan some 10,500 years ago. Pig production emerged in Eurasia, including Europe, East Asia and Southwest Asia, where wild boar were first domesticated about 10,500 years ago. In the Andes of South America, the potato was domesticated between 10,000 and 7,000 years ago, along with beans, coca, llamas, alpacas, and guinea pigs. Sugarcane and some root vegetables were domesticated in New Guinea around 9,000 years ago. Sorghum was domesticated in the Sahel region of Africa by 7,000 years ago. Cotton was domesticated in Peru by 5,600 years ago, and was independently domesticated in Eurasia. In Mesoamerica, wild teosinte was bred into maize (corn) from 10,000 to 6,000 years ago. The horse was domesticated in the Eurasian Steppes around 3500 BC. Scholars have offered multiple hypotheses to explain the historical origins of agriculture. Studies of the transition from hunter-gatherer to agricultural societies indicate an initial period of intensification and increasing sedentism; examples are the Natufian culture in the Levant, and the Early Chinese Neolithic in China. Then, wild stands that had previously been harvested started to be planted, and gradually came to be domesticated.

Civilizations
In Eurasia, the Sumerians started to live in villages from about 8,000 BC, relying on the Tigris and Euphrates rivers and a canal system for irrigation. Ploughs appear in pictographs around 3,000 BC; seed-ploughs around 2,300 BC. Farmers grew wheat, barley, vegetables such as lentils and onions, and fruits including dates, grapes, and figs. Ancient Egyptian agriculture relied on the Nile River and its seasonal flooding. Farming started in the predynastic period at the end of the Paleolithic, after 10,000 BC. Staple food crops were grains such as wheat and barley, alongside industrial crops such as flax and papyrus. In India, wheat, barley and jujube were domesticated by 9,000 BC, soon followed by sheep and goats. Cattle, sheep and goats were domesticated in Mehrgarh culture by 8,000–6,000 BC. Cotton was cultivated by the 5th–4th millennium BC. Archeological evidence indicates an animal-drawn plough from 2,500 BC in the Indus Valley civilisation. In China, from the 5th century BC, there was a nationwide granary system and widespread silk farming. Water-powered grain mills were in use by the 1st century BC, followed by irrigation. By the late 2nd century, heavy ploughs had been developed with iron ploughshares and mouldboards. These spread westwards across Eurasia. Asian rice was domesticated 8,200–13,500 years ago – depending on the molecular clock estimate that is used – on the Pearl River in southern China with a single genetic origin from the wild rice Oryza rufipogon. In Greece and Rome, the major cereals were wheat, emmer, and barley, alongside vegetables including peas, beans, and olives. Sheep and goats were kept mainly for dairy products.

In the Americas, crops domesticated in Mesoamerica (apart from teosinte) include squash, beans, and cacao. Cocoa was domesticated by the Mayo Chinchipe of the upper Amazon around 3,000 BC. The turkey was probably domesticated in Mexico or the American Southwest. The Aztecs developed irrigation systems, formed terraced hillsides, fertilized their soil, and developed chinampas or artificial islands. The Mayas used extensive canal and raised field systems to farm swampland from 400 BC. In South America agriculture may have begun about 9000 BC with the domestication of squash (Cucurbita) and other plants. Coca was domesticated in the Andes, as were the peanut, tomato, tobacco, and pineapple. Cotton was domesticated in Peru by 3,600 BC. Animals including llamas, alpacas, and guinea pigs were domesticated there. In North America, the indigenous people of the East domesticated crops such as sunflower, tobacco, squash and Chenopodium. Wild foods including wild rice and maple sugar were harvested. The domesticated strawberry is a hybrid of a Chilean and a North American species, developed by breeding in Europe and North America. The indigenous people of the Southwest and the Pacific Northwest practiced forest gardening and fire-stick farming. The natives controlled fire on a regional scale to create a low-intensity fire ecology that sustained a low-density agriculture in loose rotation; a sort of "wild" permaculture. A system of companion planting called the Three Sisters was developed in North America. The three crops were winter squash, maize, and climbing beans.

Indigenous Australians, long supposed to have been nomadic hunter-gatherers, practised systematic burning, possibly to enhance natural productivity in fire-stick farming. Scholars have pointed out that hunter-gatherers need a productive environment to support gathering without cultivation. Because the forests of New Guinea have few food plants, early humans may have used "selective burning" to increase the productivity of the wild karuka fruit trees to support the hunter-gatherer way of life.

The Gunditjmara and other groups developed eel farming and fish trapping systems from some 5,000 years ago. There is evidence of 'intensification' across the whole continent over that period. In two regions of Australia, the central west coast and eastern central, early farmers cultivated yams, native millet, and bush onions, possibly in permanent settlements.

Revolution
In the Middle Ages, compared to the Roman period, agriculture in Western Europe became more focused on self-sufficiency. The agricultural population under feudalism was typically organized into manors consisting of several hundred or more acres of land presided over by a lord of the manor with a Roman Catholic church and priest.

Thanks to the exchange with the Al-Andalus where the Arab Agricultural Revolution was underway, European agriculture transformed, with improved techniques and the diffusion of crop plants, including the introduction of sugar, rice, cotton and fruit trees (such as the orange).

After 1492, the Columbian exchange brought New World crops such as maize, potatoes, tomatoes, sweet potatoes, and manioc to Europe, and Old World crops such as wheat, barley, rice, and turnips, and livestock (including horses, cattle, sheep and goats) to the Americas.

Irrigation, crop rotation, and fertilizers advanced from the 17th century with the British Agricultural Revolution, allowing global population to rise significantly. Since 1900, agriculture in developed nations, and to a lesser extent in the developing world, has seen large rises in productivity as mechanization replaces human labor, and assisted by synthetic fertilizers, pesticides, and selective breeding. The Haber-Bosch method allowed the synthesis of ammonium nitrate fertilizer on an industrial scale, greatly increasing crop yields and sustaining a further increase in global population.

Modern agriculture has raised or encountered ecological, political, and economic issues including water pollution, biofuels, genetically modified organisms, tariffs and farm subsidies, leading to alternative approaches such as the organic movement. Unsustainable farming practices in North America led to the Dust Bowl of the 1930s.

Types

Pastoralism involves managing domesticated animals. In nomadic pastoralism, herds of livestock are moved from place to place in search of pasture, fodder, and water. This type of farming is practised in arid and semi-arid regions of Sahara, Central Asia and some parts of India.

In shifting cultivation, a small area of forest is cleared by cutting and burning the trees. The cleared land is used for growing crops for a few years until the soil becomes too infertile, and the area is abandoned. Another patch of land is selected and the process is repeated. This type of farming is practiced mainly in areas with abundant rainfall where the forest regenerates quickly. This practice is used in Northeast India, Southeast Asia, and the Amazon Basin.

Subsistence farming is practiced to satisfy family or local needs alone, with little left over for transport elsewhere. It is intensively practiced in Monsoon Asia and South-East Asia. An estimated 2.5 billion subsistence farmers worked in 2018, cultivating about 60% of the earth's arable land.

Intensive farming is cultivation to maximise productivity, with a low fallow ratio and a high use of inputs (water, fertilizer, pesticide and automation). It is practiced mainly in developed countries.

Status
From the twentieth century onwards, intensive agriculture increased crop productivity. It substituted synthetic fertilizers and pesticides for labour, but caused increased water pollution, and often involved farm subsidies. Soil degradation and diseases such as stem rust are major concerns globally; approximately 40% of the world's agricultural land is seriously degraded. In recent years there has been a backlash against the environmental effects of conventional agriculture, resulting in the organic, regenerative, and sustainable agriculture movements. One of the major forces behind this movement has been the European Union, which first certified organic food in 1991 and began reform of its Common Agricultural Policy (CAP) in 2005 to phase out commodity-linked farm subsidies, also known as decoupling. The growth of organic farming has renewed research in alternative technologies such as integrated pest management, selective breeding, and controlled-environment agriculture. There are concerns about the lower yield associated with organic farming and its impact on global food security. Recent mainstream technological developments include genetically modified food.

By 2015, the agricultural output of China was the largest in the world, followed by the European Union, India and the United States. Economists measure the total factor productivity of agriculture, according to which agriculture in the United States is roughly 1.7 times more productive than it was in 1948.

Agriculture employed 873 million people in 2021, or 27% of the global workforce, compared with 1 027 million (or 40%) in 2000. The share of agriculture in global GDP was stable at around 4% since 2000 - 2023.

Despite increases in agricultural production and productivity, between 702 and 828 million people were affected by hunger in 2021. Food insecurity and malnutrition can be the result of conflict, climate extremes and variability and economic swings. It can also be caused by a country's structural characteristics such as income status and natural resource endowments as well as its political economy.

Pesticide use in agriculture went up 62% between 2000 and 2021, with the Americas accounting for half the use in 2021.

The International Fund for Agricultural Development posits that an increase in smallholder agriculture may be part of the solution to concerns about food prices and overall food security, given the favorable experience of Vietnam.

Workforce

Agriculture provides about one-quarter of all global employment, more than half in sub-Saharan Africa and almost 60 percent in low-income countries. As countries develop, other jobs have historically pulled workers away from agriculture, and labour-saving innovations increase agricultural productivity by reducing labour requirements per unit of output. Over time, a combination of labour supply and labour demand trends have driven down the share of population employed in agriculture.

During the 16th century in Europe, between 55 and 75% of the population was engaged in agriculture; by the 19th century, this had dropped to between 35 and 65%. In the same countries today, the figure is less than 10%. At the start of the 21st century, some one billion people, or over 1/3 of the available work force, were employed in agriculture. This constitutes approximately 70% of the global employment of children, and in many countries constitutes the largest percentage of women of any industry. The service sector overtook the agricultural sector as the largest global employer in 2007.

In many developed countries, immigrants help fill labour shortages in high-value agriculture activities that are difficult to mechanize. Foreign farm workers from mostly Eastern Europe, North Africa and South Asia constituted around one-third of the salaried agricultural workforce in Spain, Italy, Greece and Portugal in 2013. In the United States of America, more than half of all hired farmworkers (roughly 450,000 workers) were immigrants in 2019, although the number of new immigrants arriving in the country to work in agriculture has fallen by 75 percent in recent years and rising wages indicate this has led to a major labor shortage on U.S. farms.

Women in agriculture
Around the world, women make up a large share of the population employed in agriculture. This share is growing in all developing regions except East and Southeast Asia where women already make up about 50 percent of the agricultural workforce. Women make up 47 percent of the agricultural workforce in sub-Saharan Africa, a rate that has not changed significantly in the past few decades. However, the Food and Agriculture Organization of the United Nations (FAO) posits that the roles and responsibilities of women in agriculture may be changing – for example, from subsistence farming to wage employment, and from contributing household members to primary producers in the context of male-out-migration.

In general, women account for a greater share of agricultural employment at lower levels of economic development, as inadequate education, limited access to basic infrastructure and markets, high unpaid work burden and poor rural employment opportunities outside agriculture severely limit women's opportunities for off-farm work.

Women who work in agricultural production tend to do so under highly unfavourable conditions. They tend to be concentrated in the poorest countries, where alternative livelihoods are not available, and they maintain the intensity of their work in conditions of climate-induced weather shocks and in situations of conflict. Women are less likely to participate as entrepreneurs and independent farmers and are engaged in the production of less lucrative crops.

The gender gap in land productivity between female- and male managed farms of the same size is 24 percent. On average, women earn 18.4 percent less than men in wage employment in agriculture; this means that women receive 82 cents for every dollar earned by men. Progress has been slow in closing gaps in women's access to irrigation and in ownership of livestock, too.

Women in agriculture still have significantly less access than men to inputs, including improved seeds, fertilizers and mechanized equipment. On a positive note, the gender gap in access to mobile internet in low- and middle-income countries fell from 25 percent to 16 percent between 2017 and 2021, and the gender gap in access to bank accounts narrowed from 9 to 6 percentage points. Women are as likely as men to adopt new technologies when the necessary enabling factors are put in place and they have equal access to complementary resources.

Safety

Agriculture, specifically farming, remains a hazardous industry, and farmers worldwide remain at high risk of work-related injuries, lung disease, noise-induced hearing loss, skin diseases, as well as certain cancers related to chemical use and prolonged sun exposure. On industrialized farms, injuries frequently involve the use of agricultural machinery, and a common cause of fatal agricultural injuries in developed countries is tractor rollovers. Pesticides and other chemicals used in farming can be hazardous to worker health, and workers exposed to pesticides may experience illness or have children with birth defects. As an industry in which families commonly share in work and live on the farm itself, entire families can be at risk for injuries, illness, and death. Ages 0–6 may be an especially vulnerable population in agriculture; common causes of fatal injuries among young farm workers include drowning, machinery and motor accidents, including with all-terrain vehicles.

The International Labour Organization considers agriculture "one of the most hazardous of all economic sectors". It estimates that the annual work-related death toll among agricultural employees is at least 170,000, twice the average rate of other jobs. In addition, incidences of death, injury and illness related to agricultural activities often go unreported. The organization has developed the Safety and Health in Agriculture Convention, 2001, which covers the range of risks in the agriculture occupation, the prevention of these risks and the role that individuals and organizations engaged in agriculture should play.

In the United States, agriculture has been identified by the National Institute for Occupational Safety and Health as a priority industry sector in the National Occupational Research Agenda to identify and provide intervention strategies for occupational health and safety issues. In the European Union, the European Agency for Safety and Health at Work has issued guidelines on implementing health and safety directives in agriculture, livestock farming, horticulture, and forestry. The Agricultural Safety and Health Council of America (ASHCA) also holds a yearly summit to discuss safety.

Production
Overall production varies by country as listed.

Crop cultivation systems

Cropping systems vary among farms depending on the available resources and constraints; geography and climate of the farm; government policy; economic, social and political pressures; and the philosophy and culture of the farmer.

Shifting cultivation (or slash and burn) is a system in which forests are burnt, releasing nutrients to support cultivation of annual and then perennial crops for a period of several years. Then the plot is left fallow to regrow forest, and the farmer moves to a new plot, returning after many more years (10–20). This fallow period is shortened if population density grows, requiring the input of nutrients (fertilizer or manure) and some manual pest control. Annual cultivation is the next phase of intensity in which there is no fallow period. This requires even greater nutrient and pest control inputs.

Further industrialization led to the use of monocultures, when one cultivar is planted on a large acreage. Because of the low biodiversity, nutrient use is uniform and pests tend to build up, necessitating the greater use of pesticides and fertilizers. Multiple cropping, in which several crops are grown sequentially in one year, and intercropping, when several crops are grown at the same time, are other kinds of annual cropping systems known as polycultures.

In subtropical and arid environments, the timing and extent of agriculture may be limited by rainfall, either not allowing multiple annual crops in a year, or requiring irrigation. In all of these environments perennial crops are grown (coffee, chocolate) and systems are practiced such as agroforestry. In temperate environments, where ecosystems were predominantly grassland or prairie, highly productive annual farming is the dominant agricultural system.

Important categories of food crops include cereals, legumes, forage, fruits and vegetables. Natural fibers include cotton, wool, hemp, silk and flax. Specific crops are cultivated in distinct growing regions throughout the world. Production is listed in millions of metric tons, based on FAO estimates.

Livestock production systems

Animal husbandry is the breeding and raising of animals for meat, milk, eggs, or wool, and for work and transport. Working animals, including horses, mules, oxen, water buffalo, camels, llamas, alpacas, donkeys, and dogs, have for centuries been used to help cultivate fields, harvest crops, wrangle other animals, and transport farm products to buyers.

Livestock production systems can be defined based on feed source, as grassland-based, mixed, and landless. , 30% of Earth's ice- and water-free area was used for producing livestock, with the sector employing approximately 1.3 billion people. Between the 1960s and the 2000s, there was a significant increase in livestock production, both by numbers and by carcass weight, especially among beef, pigs and chickens, the latter of which had production increased by almost a factor of 10. Non-meat animals, such as milk cows and egg-producing chickens, also showed significant production increases. Global cattle, sheep and goat populations are expected to continue to increase sharply through 2050. Aquaculture or fish farming, the production of fish for human consumption in confined operations, is one of the fastest growing sectors of food production, growing at an average of 9% a year between 1975 and 2007.

During the second half of the 20th century, producers using selective breeding focused on creating livestock breeds and crossbreeds that increased production, while mostly disregarding the need to preserve genetic diversity. This trend has led to a significant decrease in genetic diversity and resources among livestock breeds, leading to a corresponding decrease in disease resistance and local adaptations previously found among traditional breeds.

Grassland based livestock production relies upon plant material such as shrubland, rangeland, and pastures for feeding ruminant animals. Outside nutrient inputs may be used, however manure is returned directly to the grassland as a major nutrient source. This system is particularly important in areas where crop production is not feasible because of climate or soil, representing 30–40 million pastoralists. Mixed production systems use grassland, fodder crops and grain feed crops as feed for ruminant and monogastric (one stomach; mainly chickens and pigs) livestock. Manure is typically recycled in mixed systems as a fertilizer for crops.

Landless systems rely upon feed from outside the farm, representing the de-linking of crop and livestock production found more prevalently in Organisation for Economic Co-operation and Development member countries. Synthetic fertilizers are more heavily relied upon for crop production and manure use becomes a challenge as well as a source for pollution. Industrialized countries use these operations to produce much of the global supplies of poultry and pork. Scientists estimate that 75% of the growth in livestock production between 2003 and 2030 will be in confined animal feeding operations, sometimes called factory farming. Much of this growth is happening in developing countries in Asia, with much smaller amounts of growth in Africa. Some of the practices used in commercial livestock production, including the usage of growth hormones, are controversial.

Production practices

Tillage is the practice of breaking up the soil with tools such as the plow or harrow to prepare for planting, for nutrient incorporation, or for pest control. Tillage varies in intensity from conventional to no-till. It can improve productivity by warming the soil, incorporating fertilizer and controlling weeds, but also renders soil more prone to erosion, triggers the decomposition of organic matter releasing CO2, and reduces the abundance and diversity of soil organisms.

Pest control includes the management of weeds, insects, mites, and diseases. Chemical (pesticides), biological (biocontrol), mechanical (tillage), and cultural practices are used. Cultural practices include crop rotation, culling, cover crops, intercropping, composting, avoidance, and resistance. Integrated pest management attempts to use all of these methods to keep pest populations below the number which would cause economic loss, and recommends pesticides as a last resort.

Nutrient management includes both the source of nutrient inputs for crop and livestock production, and the method of use of manure produced by livestock. Nutrient inputs can be chemical inorganic fertilizers, manure, green manure, compost and minerals. Crop nutrient use may also be managed using cultural techniques such as crop rotation or a fallow period. Manure is used either by holding livestock where the feed crop is growing, such as in managed intensive rotational grazing, or by spreading either dry or liquid formulations of manure on cropland or pastures.

Water management is needed where rainfall is insufficient or variable, which occurs to some degree in most regions of the world. Some farmers use irrigation to supplement rainfall. In other areas such as the Great Plains in the U.S. and Canada, farmers use a fallow year to conserve soil moisture for the following year. Recent technological innovations in precision agriculture allow for water status monitoring and automate water usage, leading to more efficient management. Agriculture represents 70% of freshwater use worldwide. However, water withdrawal ratios for agriculture vary significantly by income level. In least developed countries and landlocked developing countries, water withdrawal ratios for agriculture are as high as 90 percent of total water withdrawals and about 60 percent in Small Island Developing States.

According to 2014 report by the International Food Policy Research Institute, agricultural technologies will have the greatest impact on food production if adopted in combination with each other. Using a model that assessed how eleven technologies could impact agricultural productivity, food security and trade by 2050, the International Food Policy Research Institute found that the number of people at risk from hunger could be reduced by as much as 40% and food prices could be reduced by almost half.

Payment for ecosystem services is a method of providing additional incentives to encourage farmers to conserve some aspects of the environment. Measures might include paying for reforestation upstream of a city, to improve the supply of fresh water.

Agricultural automation
Different definitions exist for agricultural automation and for the variety of tools and technologies that are used to automate production. One view is that agricultural automation refers to autonomous navigation by robots without human intervention. Alternatively it is defined as the accomplishment of production tasks through mobile, autonomous, decision-making, mechatronic devices. However, FAO finds that these definitions do not capture all the aspects and forms of automation, such as robotic milking machines that are static, most motorized machinery that automates the performing of agricultural operations, and digital tools (e.g., sensors) that automate only diagnosis. FAO defines agricultural automation as the use of machinery and equipment in agricultural operations to improve their diagnosis, decision-making or performing, reducing the drudgery of agricultural work or improving the timeliness, and potentially the precision, of agricultural operations.

The technological evolution in agriculture has involved a progressive move from manual tools to animal traction, to motorized mechanization, to digital equipment and finally, to robotics with artificial intelligence (AI). Motorized mechanization using engine power automates the performance of agricultural operations such as ploughing and milking. With digital automation technologies, it also becomes possible to automate diagnosis and decision-making of agricultural operations. For example, autonomous crop robots can harvest and seed crops, while drones can gather information to help automate input application. Precision agriculture often employs such automation technologies. Motorized machines are increasingly complemented, or even superseded, by new digital equipment that automates diagnosis and decision-making. A conventional tractor, for example, can be converted into an automated vehicle allowing it to sow a field autonomously.

Motorized mechanization has increased significantly across the world in recent years, although reliable global data with broad country coverage exist only for tractors and only up to 2009. Sub-Saharan Africa is the only region where the adoption of motorized mechanization has stalled over the past decades.

Automation technologies are increasingly used for managing livestock, though evidence on adoption is lacking. Global automatic milking system sales have increased over recent years, but adoption is likely mostly in Northern Europe, and likely almost absent in low- and middle-income countries. Automated feeding machines for both cows and poultry also exist, but data and evidence regarding their adoption trends and drivers is likewise scarce.

Measuring the overall employment impacts of agricultural automation is difficult because it requires large amounts of data tracking all the transformations and the associated reallocation of workers both upstream and downstream. While automation technologies reduce labour needs for the newly automated tasks, they also generate new labour demand for other tasks, such as equipment maintenance and operation. Agricultural automation can also stimulate employment by allowing producers to expand production and by creating other agrifood systems jobs. This is especially true when it happens in context of rising scarcity of rural labour, as is the case in high-income countries and many middle-income countries. On the other hand, if forcedly promoted, for example through government subsidies in contexts of abundant rural labour, it can lead to labour displacement and falling or stagnant wages, particularly affecting poor and low-skilled workers.

Effects of climate change on yields
Climate change and agriculture are interrelated on a global scale. Climate change affects agriculture through changes in average temperatures, rainfall, and weather extremes (like storms and heat waves); changes in pests and diseases; changes in atmospheric carbon dioxide and ground-level ozone concentrations; changes in the nutritional quality of some foods; and changes in sea level. Global warming is already affecting agriculture, with effects unevenly distributed across the world.

In a 2022 report, the Intergovernmental Panel on Climate Change describes how human-induced warming has slowed growth of agricultural productivity over the past 50 years in mid and low latitudes. Methane emissions have negatively impacted crop yields by increasing temperatures and surface ozone concentrations. Warming is also negatively affecting crop and grassland quality and harvest stability. Ocean warming has decreased sustainable yields of some wild fish populations while ocean acidification and warming have already affected farmed aquatic species. Climate change will probably increase the risk of food insecurity for some vulnerable groups, such as the poor.

Plant breeding

Crop alteration has been practiced by humankind for thousands of years, since the beginning of civilization. Altering crops through breeding practices changes the genetic make-up of a plant to develop crops with more beneficial characteristics for humans, for example, larger fruits or seeds, drought-tolerance, or resistance to pests. Significant advances in plant breeding ensued after the work of geneticist Gregor Mendel. His work on dominant and recessive alleles, although initially largely ignored for almost 50 years, gave plant breeders a better understanding of genetics and breeding techniques. Crop breeding includes techniques such as plant selection with desirable traits, self-pollination and cross-pollination, and molecular techniques that genetically modify the organism.

Domestication of plants has, over the centuries increased yield, improved disease resistance and drought tolerance, eased harvest and improved the taste and nutritional value of crop plants. Careful selection and breeding have had enormous effects on the characteristics of crop plants. Plant selection and breeding in the 1920s and 1930s improved pasture (grasses and clover) in New Zealand. Extensive X-ray and ultraviolet induced mutagenesis efforts (i.e. primitive genetic engineering) during the 1950s produced the modern commercial varieties of grains such as wheat, corn (maize) and barley. The Green Revolution popularized the use of conventional hybridization to sharply increase yield by creating "high-yielding varieties". For example, average yields of corn (maize) in the US have increased from around 2.5 tons per hectare (t/ha) (40 bushels per acre) in 1900 to about 9.4 t/ha (150 bushels per acre) in 2001. Similarly, worldwide average wheat yields have increased from less than 1 t/ha in 1900 to more than 2.5 t/ha in 1990. South American average wheat yields are around 2 t/ha, African under 1 t/ha, and Egypt and Arabia up to 3.5 to 4 t/ha with irrigation. In contrast, the average wheat yield in countries such as France is over 8 t/ha. Variations in yields are due mainly to variation in climate, genetics, and the level of intensive farming techniques (use of fertilizers, chemical pest control, and growth control to avoid lodging).

Genetic engineering

Genetically modified organisms (GMO) are organisms whose genetic material has been altered by genetic engineering techniques generally known as recombinant DNA technology. Genetic engineering has expanded the genes available to breeders to use in creating desired germlines for new crops. Increased durability, nutritional content, insect and virus resistance and herbicide tolerance are a few of the attributes bred into crops through genetic engineering. For some, GMO crops cause food safety and food labeling concerns. Numerous countries have placed restrictions on the production, import or use of GMO foods and crops. The Biosafety Protocol, an international treaty, regulates the trade of GMOs. There is ongoing discussion regarding the labeling of foods made from GMOs, and while the EU currently requires all GMO foods to be labeled, the US does not.

Herbicide-resistant seeds have a gene implanted into their genome that allows the plants to tolerate exposure to herbicides, including glyphosate. These seeds allow the farmer to grow a crop that can be sprayed with herbicides to control weeds without harming the resistant crop. Herbicide-tolerant crops are used by farmers worldwide. With the increasing use of herbicide-tolerant crops, comes an increase in the use of glyphosate-based herbicide sprays. In some areas glyphosate resistant weeds have developed, causing farmers to switch to other herbicides. Some studies also link widespread glyphosate usage to iron deficiencies in some crops, which is both a crop production and a nutritional quality concern, with potential economic and health implications.

Other GMO crops used by growers include insect-resistant crops, which have a gene from the soil bacterium Bacillus thuringiensis (Bt), which produces a toxin specific to insects. These crops resist damage by insects. Some believe that similar or better pest-resistance traits can be acquired through traditional breeding practices, and resistance to various pests can be gained through hybridization or cross-pollination with wild species. In some cases, wild species are the primary source of resistance traits; some tomato cultivars that have gained resistance to at least 19 diseases did so through crossing with wild populations of tomatoes.

Effects and costs

Agriculture is both a cause of and sensitive to environmental degradation, such as biodiversity loss, desertification, soil degradation and climate change, which cause decreases in crop yield. Agriculture is one of the most important drivers of environmental pressures, particularly habitat change, climate change, water use and toxic emissions. Agriculture is the main source of toxins released into the environment, including insecticides, especially those used on cotton. The 2011 UNEP Green Economy report stated that agricultural operations produced some 13 per cent of anthropogenic global greenhouse gas emissions. This includes gases from the use of inorganic fertilizers, agro-chemical pesticides, and herbicides, as well as fossil fuel-energy inputs.

Agriculture imposes multiple external costs upon society through effects such as pesticide damage to nature (especially herbicides and insecticides), nutrient runoff, excessive water usage, and loss of natural environment. A 2000 assessment of agriculture in the UK determined total external costs for 1996 of £2,343 million, or £208 per hectare. A 2005 analysis of these costs in the US concluded that cropland imposes approximately $5 to $16 billion ($30 to $96 per hectare), while livestock production imposes $714 million. Both studies, which focused solely on the fiscal impacts, concluded that more should be done to internalize external costs. Neither included subsidies in their analysis, but they noted that subsidies also influence the cost of agriculture to society.

Agriculture seeks to increase yield and to reduce costs, often employing measures that cut biodiversity to very low levels. Yield increases with inputs such as fertilisers and removal of pathogens, predators, and competitors (such as weeds). Costs decrease with increasing scale of farm units, such as making fields larger; this means removing hedges, ditches and other areas of habitat. Pesticides kill insects, plants and fungi. Effective yields fall with on-farm losses, which may be caused by poor production practices during harvesting, handling, and storage.

The environmental effects of climate change show that research on pests and diseases that do not generally afflict areas is essential. In 2021, farmers discovered stem rust on wheat in the Champagne area of France, a disease that had previously only occurred in Morocco for 20 to 30 years. Because of climate change, insects that used to die off over the winter are now alive and multiplying.

Livestock issues

A senior UN official, Henning Steinfeld, said that "Livestock are one of the most significant contributors to today's most serious environmental problems". Livestock production occupies 70% of all land used for agriculture, or 30% of the land surface of the planet. It is one of the largest sources of greenhouse gases, responsible for 18% of the world's greenhouse gas emissions as measured in CO2 equivalents. By comparison, all transportation emits 13.5% of the CO2. It produces 65% of human-related nitrous oxide (which has 296 times the global warming potential of CO2) and 37% of all human-induced methane (which is 23 times as warming as CO2.) It also generates 64% of the ammonia emission. Livestock expansion is cited as a key factor driving deforestation; in the Amazon basin 70% of previously forested area is now occupied by pastures and the remainder used for feed crops. Through deforestation and land degradation, livestock is also driving reductions in biodiversity. A well documented phenomenon is woody plant encroachment, caused by overgrazing in rangelands. Furthermore, the United Nations Environment Programme (UNEP) states that "methane emissions from global livestock are projected to increase by 60 per cent by 2030 under current practices and consumption patterns."

Land and water issues

Land transformation, the use of land to yield goods and services, is the most substantial way humans alter the Earth's ecosystems, and is the driving force causing biodiversity loss. Estimates of the amount of land transformed by humans vary from 39 to 50%. It is estimated that 24% of land globally experiences land degradation, a long-term decline in ecosystem function and productivity, with cropland being disproportionately affected. Land management is the driving factor behind degradation; 1.5 billion people rely upon the degrading land. Degradation can be through deforestation, desertification, soil erosion, mineral depletion, acidification, or salinization. In 2021, the global agricultural land area was 4.79 billion hectares (ha), down 2 percent, or 0.09 billion ha compared with 2000. Between 2000 and 2021, roughly two-thirds of agricultural land were used for permanent meadows and pastures (3.21 billion ha in 2021), which declined by 5 percent (0.17 billion ha). One-third of the total agricultural land was cropland (1.58 billion ha in 2021), which increased by 6 percent (0.09 billion ha).

Eutrophication, excessive nutrient enrichment in aquatic ecosystems resulting in algal blooms and anoxia, leads to fish kills, loss of biodiversity, and renders water unfit for drinking and other industrial uses. Excessive fertilization and manure application to cropland, as well as high livestock stocking densities cause nutrient (mainly nitrogen and phosphorus) runoff and leaching from agricultural land. These nutrients are major nonpoint pollutants contributing to eutrophication of aquatic ecosystems and pollution of groundwater, with harmful effects on human populations. Fertilisers also reduce terrestrial biodiversity by increasing competition for light, favouring those species that are able to benefit from the added nutrients.

Agriculture simultaneously is facing growing freshwater demand and precipitation anomalies (droughts, floods, and extreme rainfall and weather events) on rainfed areasfields and grazing lands. Agriculture accounts for 70 percent of withdrawals of freshwater resources, and an estimated 41 percent of current global irrigation water use occurs at the expense of environmental flow requirements. It is long known that aquifers in areas as diverse as northern China, the Upper Ganges and the western US are being depleted, and new research extends these problems to aquifers in Iran, Mexico and Saudi Arabia. Increasing pressure is being placed on water resources by industry and urban areas, meaning that water scarcity is increasing and agriculture is facing the challenge of producing more food for the world's growing population with reduced water resources. While industrial withdrawals have declined in the past few decades and municipal withdrawals have increased only marginally since 2010, agricultural withdrawals have continued to grow at an ever faster pace. Agricultural water usage can also cause major environmental problems, including the destruction of natural wetlands, the spread of water-borne diseases, and land degradation through salinization and waterlogging, when irrigation is performed incorrectly.

Pesticides

Pesticide use has increased since 1950 to 2.5 million short tons annually worldwide, yet crop loss from pests has remained relatively constant. The World Health Organization estimated in 1992 that three million pesticide poisonings occur annually, causing 220,000 deaths. Pesticides select for pesticide resistance in the pest population, leading to a condition termed the "pesticide treadmill" in which pest resistance warrants the development of a new pesticide.

An alternative argument is that the way to "save the environment" and prevent famine is by using pesticides and intensive high yield farming, a view exemplified by a quote heading the Center for Global Food Issues website: 'Growing more per acre leaves more land for nature'. However, critics argue that a trade-off between the environment and a need for food is not inevitable, and that pesticides can replace good agronomic practices such as crop rotation. The Push–pull agricultural pest management technique involves intercropping, using plant aromas to repel pests from crops (push) and to lure them to a place from which they can then be removed (pull).

Contribution to climate change
Agriculture contributes towards climate change through greenhouse gas emissions and by the conversion of non-agricultural land such as forests into agricultural land. The agriculture, forestry and land use sector contribute between 13% and 21% of global greenhouse gas emissions. Emissions of nitrous oxide, methane make up over half of total greenhouse gas emission from agriculture. Animal husbandry is a major source of greenhouse gas emissions.

Approximately 57% of global GHG emissions from the production of food are from the production of animal-based food while plant-based foods contribute 29% and the remaining 14% is for other utilizations. Farmland management and land-use change represented major shares of total emissions (38% and 29%, respectively), whereas rice and beef were the largest contributing plant- and animal-based commodities (12% and 25%, respectively). South and Southeast Asia and South America were the largest emitters of production-based GHGs.

Sustainability

Current farming methods have resulted in over-stretched water resources, high levels of erosion and reduced soil fertility. There is not enough water to continue farming using current practices; therefore how water, land, and ecosystem resources are used to boost crop yields must be reconsidered. A solution would be to give value to ecosystems, recognizing environmental and livelihood tradeoffs, and balancing the rights of a variety of users and interests. Inequities that result when such measures are adopted would need to be addressed, such as the reallocation of water from poor to rich, the clearing of land to make way for more productive farmland, or the preservation of a wetland system that limits fishing rights.

Technological advancements help provide farmers with tools and resources to make farming more sustainable. Technology permits innovations like conservation tillage, a farming process which helps prevent land loss to erosion, reduces water pollution, and enhances carbon sequestration.

Agricultural automation can help address some of the challenges associated with climate change and thus facilitate adaptation efforts. For example, the application of digital automation technologies (e.g. in precision agriculture) can improve resource-use efficiency in conditions which are increasingly constrained for agricultural producers. Moreover, when applied to sensing and early warning, they can help address the uncertainty and unpredictability of weather conditions associated with accelerating climate change.

Other potential sustainable practices include conservation agriculture, agroforestry, improved grazing, avoided grassland conversion, and biochar. Current mono-crop farming practices in the United States preclude widespread adoption of sustainable practices, such as 2–3 crop rotations that incorporate grass or hay with annual crops, unless negative emission goals such as soil carbon sequestration become policy.

The food demand of Earth's projected population, with current climate change predictions, could be satisfied by improvement of agricultural methods, expansion of agricultural areas, and a sustainability-oriented consumer mindset.

Energy dependence

Since the 1940s, agricultural productivity has increased dramatically, due largely to the increased use of energy-intensive mechanization, fertilizers and pesticides. The vast majority of this energy input comes from fossil fuel sources. Between the 1960s and the 1980s, the Green Revolution transformed agriculture around the globe, with world grain production increasing significantly (between 70% and 390% for wheat and 60% to 150% for rice, depending on geographic area) as world population doubled. Heavy reliance on petrochemicals has raised concerns that oil shortages could increase costs and reduce agricultural output.

Industrialized agriculture depends on fossil fuels in two fundamental ways: direct consumption on the farm and manufacture of inputs used on the farm. Direct consumption includes the use of lubricants and fuels to operate farm vehicles and machinery.

Indirect consumption includes the manufacture of fertilizers, pesticides, and farm machinery. In particular, the production of nitrogen fertilizer can account for over half of agricultural energy usage. Together, direct and indirect consumption by US farms accounts for about 2% of the nation's energy use. Direct and indirect energy consumption by U.S. farms peaked in 1979, and has since gradually declined. Food systems encompass not just agriculture but off-farm processing, packaging, transporting, marketing, consumption, and disposal of food and food-related items. Agriculture accounts for less than one-fifth of food system energy use in the US.

Plastic pollution
Plastic products are used extensively in agriculture, including to increase crop yields and improve the efficiency of water and agrichemical use. "Agriplastic" products include films to cover greenhouses and tunnels, mulch to cover soil (e.g. to suppress weeds, conserve water, increase soil temperature and aid fertilizer application), shade cloth, pesticide containers, seedling trays, protective mesh and irrigation tubing. The polymers most commonly used in these products are low- density polyethylene (LPDE), linear low-density polyethylene (LLDPE), polypropylene (PP) and polyvinyl chloride (PVC).

The total amount of plastics used in agriculture is difficult to quantify. A 2012 study reported that almost 6.5 million tonnes per year were consumed globally while a later study estimated that global demand in 2015 was between 7.3 million and 9 million tonnes. Widespread use of plastic mulch and lack of systematic collection and management have led to the generation of large amounts of mulch residue. Weathering and degradation eventually cause the mulch to fragment. These fragments and larger pieces of plastic accumulate in soil. Mulch residue has been measured at levels of 50 to 260 kg per hectare in topsoil in areas where mulch use dates back more than 10 years, which confirms that mulching is a major source of both microplastic and macroplastic soil contamination.

Agricultural plastics, especially plastic films, are not easy to recycle because of high contamination levels (up to 40–50% by weight contamination by pesticides, fertilizers, soil and debris, moist vegetation, silage juice water, and UV stabilizers) and collection difficulties. Therefore, they are often buried or abandoned in fields and watercourses or burned. These disposal practices lead to soil degradation and can result in contamination of soils and leakage of microplastics into the marine environment as a result of precipitation run-off and tidal washing. In addition, additives in residual plastic film (such as UV and thermal stabilizers) may have deleterious effects on crop growth, soil structure, nutrient transport and salt levels. There is a risk that plastic mulch will deteriorate soil quality, deplete soil organic matter stocks, increase soil water repellence and emit greenhouse gases. Microplastics released through fragmentation of agricultural plastics can absorb and concentrate contaminants capable of being passed up the trophic chain.

Agricultural economics

Agricultural economics is economics as it relates to the "production, distribution and consumption of [agricultural] goods and services". Combining agricultural production with general theories of marketing and business as a discipline of study began in the late 1800s, and grew significantly through the 20th century. Although the study of agricultural economics is relatively recent, major trends in agriculture have significantly affected national and international economies throughout history, ranging from tenant farmers and sharecropping in the post-American Civil War Southern United States to the European feudal system of manorialism. In the United States, and elsewhere, food costs attributed to food processing, distribution, and agricultural marketing, sometimes referred to as the value chain, have risen while the costs attributed to farming have declined. This is related to the greater efficiency of farming, combined with the increased level of value addition (e.g. more highly processed products) provided by the supply chain. Market concentration has increased in the sector as well, and although the total effect of the increased market concentration is likely increased efficiency, the changes redistribute economic surplus from producers (farmers) and consumers, and may have negative implications for rural communities.

National government policies, such as taxation, subsidies, tariffs and others, can significantly change the economic marketplace for agricultural products. Since at least the 1960s, a combination of trade restrictions, exchange rate policies and subsidies have affected farmers in both the developing and the developed world. In the 1980s, non-subsidized farmers in developing countries experienced adverse effects from national policies that created artificially low global prices for farm products. Between the mid-1980s and the early 2000s, several international agreements limited agricultural tariffs, subsidies and other trade restrictions.

However,, there was still a significant amount of policy-driven distortion in global agricultural product prices. The three agricultural products with the most trade distortion were sugar, milk and rice, mainly due to taxation. Among the oilseeds, sesame had the most taxation, but overall, feed grains and oilseeds had much lower levels of taxation than livestock products. Since the 1980s, policy-driven distortions have decreases more among livestock products than crops during the worldwide reforms in agricultural policy. Despite this progress, certain crops, such as cotton, still see subsidies in developed countries artificially deflating global prices, causing hardship in developing countries with non-subsidized farmers. Unprocessed commodities such as corn, soybeans, and cattle are generally graded to indicate quality, affecting the price the producer receives. Commodities are generally reported by production quantities, such as volume, number or weight.

Agricultural science

Agricultural science is a broad multidisciplinary field of biology that encompasses the parts of exact, natural, economic and social sciences used in the practice and understanding of agriculture. It covers topics such as agronomy, plant breeding and genetics, plant pathology, crop modelling, soil science, entomology, production techniques and improvement, study of pests and their management, and study of adverse environmental effects such as soil degradation, waste management, and bioremediation.

The scientific study of agriculture began in the 18th century, when Johann Friedrich Mayer conducted experiments on the use of gypsum (hydrated calcium sulphate) as a fertilizer. Research became more systematic when in 1843, John Lawes and Henry Gilbert began a set of long-term agronomy field experiments at Rothamsted Research Station in England; some of them, such as the Park Grass Experiment, are still running. In America, the Hatch Act of 1887 provided funding for what it was the first to call "agricultural science", driven by farmers' interest in fertilizers. In agricultural entomology, the USDA began to research biological control in 1881; it instituted its first large program in 1905, searching Europe and Japan for natural enemies of the spongy moth and brown-tail moth, establishing parasitoids (such as solitary wasps) and predators of both pests in the US.

Policy
Agricultural policy is the set of government decisions and actions relating to domestic agriculture and imports of foreign agricultural products. Governments usually implement agricultural policies with the goal of achieving a specific outcome in the domestic agricultural product markets. Some overarching themes include risk management and adjustment (including policies related to climate change, food safety and natural disasters), economic stability (including policies related to taxes), natural resources and environmental sustainability (especially water policy), research and development, and market access for domestic commodities (including relations with global organizations and agreements with other countries). Agricultural policy can also touch on food quality, ensuring that the food supply is of a consistent and known quality, food security, ensuring that the food supply meets the population's needs, and conservation. Policy programs can range from financial programs, such as subsidies, to encouraging producers to enroll in voluntary quality assurance programs.

A 2021 report finds that globally, support to agricultural producers accounts for almost US$540 billion a year. This amounts to 15 percent of total agricultural production value, and is heavily biased towards measures that are leading to inefficiency, as well as are unequally distributed and harmful for the environment and human health.

There are many influences on the creation of agricultural policy, including consumers, agribusiness, trade lobbies and other groups. Agribusiness interests hold a large amount of influence over policy making, in the form of lobbying and campaign contributions. Political action groups, including those interested in environmental issues and labor unions, also provide influence, as do lobbying organizations representing individual agricultural commodities. The Food and Agriculture Organization of the United Nations (FAO) leads international efforts to defeat hunger and provides a forum for the negotiation of global agricultural regulations and agreements. Samuel Jutzi, director of FAO's animal production and health division, states that lobbying by large corporations has stopped reforms that would improve human health and the environment. For example, proposals in 2010 for a voluntary code of conduct for the livestock industry that would have provided incentives for improving standards for health, and environmental regulations, such as the number of animals an area of land can support without long-term damage, were successfully defeated due to large food company pressure.

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title: Agriculture


text:
Aldous Huxley

Aldous Leonard Huxley (26 July 1894 – 22 November 1963) was an English writer and philosopher. His bibliography spans nearly 50 books, including novels and non-fiction works, as well as essays, narratives, and poems.

Born into the prominent Huxley family, he graduated from Balliol College, Oxford, with an undergraduate degree in English literature. Early in his career, he published short stories and poetry and edited the literary magazine Oxford Poetry, before going on to publish travel writing, satire, and screenplays. He spent the latter part of his life in the United States, living in Los Angeles from 1937 until his death. By the end of his life, Huxley was widely acknowledged as one of the foremost intellectuals of his time. He was nominated for the Nobel Prize in Literature nine times, and was elected Companion of Literature by the Royal Society of Literature in 1962.

Huxley was a pacifist. He grew interested in philosophical mysticism, as well as universalism, addressing these subjects in his works such as The Perennial Philosophy (1945), which illustrates commonalities between Western and Eastern mysticism, and The Doors of Perception (1954), which interprets his own psychedelic experience with mescaline. In his most famous novel Brave New World (1932) and his final novel Island (1962), he presented his visions of dystopia and utopia, respectively.

Early life
Huxley was born in Godalming, Surrey, England, on 26 July 1894. He was the third son of the writer and schoolmaster Leonard Huxley, who edited The Cornhill Magazine, and his first wife, Julia Arnold, who founded Prior's Field School. Julia was the niece of poet and critic Matthew Arnold and the sister of Mrs. Humphry Ward. Julia named him Aldous after a character in one of her sister's novels. Aldous was the grandson of Thomas Henry Huxley, the zoologist, agnostic, and controversialist who had often been called "Darwin's Bulldog". His brother Julian Huxley and half-brother Andrew Huxley also became outstanding biologists. Aldous had another brother, Noel Trevenen Huxley (1889–1914), who took his own life after a period of clinical depression.

As a child, Huxley's nickname was "Ogie", short for "Ogre". He was described by his brother, Julian, as someone who frequently contemplated "the strangeness of things". According to his cousin and contemporary Gervas Huxley, he had an early interest in drawing.

Huxley's education began in his father's well-equipped botanical laboratory, after which he enrolled at Hillside School near Godalming. He was taught there by his own mother for several years until she became terminally ill. After Hillside he went on to Eton College. His mother died in 1908, when he was 14 (his father later remarried). He contracted the eye disease keratitis punctata in 1911; this "left [him] practically blind for two to three years" and "ended his early dreams of becoming a doctor". In October 1913, Huxley entered Balliol College, Oxford, where he studied English literature. He volunteered for the British Army in January 1916, for the Great War; however, he was rejected on health grounds, being half-blind in one eye. His eyesight later partly recovered. He edited Oxford Poetry in 1916, and in June of that year graduated BA with first class honours. His brother Julian wrote:

"I believe his blindness was a blessing in disguise. For one thing, it put paid to his idea of taking up medicine as a career ... His uniqueness lay in his universalism. He was able to take all knowledge for his province."

Following his years at Balliol, Huxley, being financially indebted to his father, decided to find employment. He taught French for a year at Eton College, where Eric Blair (who was to take the pen name George Orwell) and Steven Runciman were among his pupils. He was mainly remembered as being an incompetent schoolmaster unable to keep order in class. Nevertheless, Blair and others spoke highly of his excellent command of language.

Huxley also worked for a time during the 1920s at Brunner and Mond, an advanced chemical plant in Billingham in County Durham, northeast England. According to an introduction to his science fiction novel Brave New World (1932), the experience he had there of "an ordered universe in a world of planless incoherence" was an important source for the novel.

Career
Huxley completed his first (unpublished) novel at the age of 17 and began writing seriously in his early twenties, establishing himself as a successful writer and social satirist. His first published novels were social satires, Crome Yellow (1921), Antic Hay (1923), Those Barren Leaves (1925), and Point Counter Point (1928). Brave New World (1932) was his fifth novel and first dystopian work. In the 1920s, he was also a contributor to Vanity Fair and British Vogue magazines.

Contact with the Bloomsbury Set
During the First World War, Huxley spent much of his time at Garsington Manor near Oxford, home of Lady Ottoline Morrell, working as a farm labourer. While at the Manor, he met several Bloomsbury Group figures, including Bertrand Russell, Alfred North Whitehead, and Clive Bell. Later, in Crome Yellow (1921), he caricatured the Garsington lifestyle. Jobs were very scarce, but in 1919, John Middleton Murry was reorganising the Athenaeum and invited Huxley to join the staff. He accepted immediately, and quickly married the Belgian refugee Maria Nys (1899–1955), also at Garsington. They lived with their young son in Italy part of the time during the 1920s, where Huxley would visit his friend D. H. Lawrence. Following Lawrence's death in 1930 (he and Maria were present at his death in Provence), Huxley edited Lawrence's letters (1932). Very early in 1929, in London, Huxley met Gerald Heard, a writer and broadcaster, philosopher and interpreter of contemporary science.

Works of this period included novels about the dehumanising aspects of scientific progress, (his magnum opus Brave New World), and on pacifist themes (Eyeless in Gaza). In Brave New World, set in a dystopian London, Huxley portrays a society operating on the principles of mass production and Pavlovian conditioning. Huxley was strongly influenced by F. Matthias Alexander, on whom he based a character in Eyeless in Gaza.

During this period, Huxley began to write and edit non-fiction works on pacifist issues, including Ends and Means (1937), An Encyclopedia of Pacifism, and Pacifism and Philosophy, and was an active member of the Peace Pledge Union.

Life in the United States
In 1937, Huxley moved to Hollywood with his wife Maria, son Matthew Huxley, and friend Gerald Heard. Cyril Connolly wrote, of the two intellectuals (Huxley and Heard) in the late 1930s, "all European avenues had been exhausted in the search for a way forward – politics, art, science – pitching them both toward the US in 1937." Huxley lived in the U.S., mainly southern California,  until his death, and for a time in Taos, New Mexico, where he wrote Ends and Means (1937). The book contains tracts on war, inequality, religion and ethics.

Heard introduced Huxley to Vedanta (Upanishad-centered philosophy), meditation, and vegetarianism through the principle of ahimsa. In 1938, Huxley befriended Jiddu Krishnamurti, whose teachings he greatly admired. Huxley and Krishnamurti entered into an enduring exchange (sometimes edging on debate) over many years, with Krishnamurti representing the more rarefied, detached, ivory-tower perspective and Huxley, with his pragmatic concerns, the more socially and historically informed position. Huxley wrote a foreword to Krishnamurti's quintessential statement, The First and Last Freedom (1954).

Huxley and Heard became Vedantists in the group formed around Hindu Swami Prabhavananda, and subsequently introduced Christopher Isherwood to the circle. Not long afterwards, Huxley wrote his book on widely held spiritual values and ideas, The Perennial Philosophy, which discussed the teachings of renowned mystics of the world.

Huxley became a close friend of Remsen Bird, president of Occidental College. He spent much time at the college in the Eagle Rock neighbourhood of Los Angeles. The college appears as "Tarzana College" in his satirical novel After Many a Summer (1939). The novel won Huxley a British literary award, the 1939 James Tait Black Memorial Prize for fiction. Huxley also incorporated Bird into the novel.

During this period, Huxley earned a substantial income as a Hollywood screenwriter; Christopher Isherwood, in his autobiography My Guru and His Disciple, states that Huxley earned more than $3,000 per week (approximately $50,000 in 2020 dollars) as a screenwriter, and that he used much of it to transport Jewish and left-wing writer and artist refugees from Hitler's Germany to the US. In March 1938, Huxley's friend Anita Loos, a novelist and screenwriter, put him in touch with Metro-Goldwyn-Mayer (MGM), which hired him for Madame Curie which was originally to star Greta Garbo and be directed by George Cukor. (Eventually, the film was completed by MGM in 1943 with a different director and cast.) Huxley received screen credit for Pride and Prejudice (1940) and was paid for his work on a number of other films, including Jane Eyre (1944). He was commissioned by Walt Disney in 1945 to write a script based on Alice's Adventures in Wonderland and the biography of the story's author, Lewis Carroll. The script was not used, however.

Huxley wrote an introduction to the posthumous publication of J. D. Unwin's 1940 book Hopousia or The Sexual and Economic Foundations of a New Society.

On 21 October 1949, Huxley wrote to George Orwell, author of Nineteen Eighty-Four, congratulating him on "how fine and how profoundly important the book is". In his letter, he predicted: "'Within the next generation I believe that the world's leaders will discover that infant conditioning and narcohypnosis are more efficient, as instruments of government, than clubs and prisons, and that the lust for power can be just as completely satisfied by suggesting people into loving their servitude as by flogging them and kicking them into obedience.'"

In 1953, Huxley and Maria applied for United States citizenship and presented themselves for examination. When Huxley refused to bear arms for the U.S. and would not state that his objections were based on religious ideals, the only excuse allowed under the McCarran Act, the judge had to adjourn the proceedings. He withdrew his application. Nevertheless, he remained in the U.S. In 1959, Huxley turned down an offer to be made a Knight Bachelor by the Macmillan government without giving a reason; his brother Julian had been knighted in 1958, while his brother Andrew would be knighted in 1974.

In the fall semester of 1960 Huxley was invited by Professor Huston Smith to be the Carnegie Visiting professor of humanities at the Massachusetts Institute of Technology (MIT). As part of the MIT centennial program of events organised by the Department of Humanities, Huxley presented a series of lectures titled, "What a Piece of Work is a Man" which concerned history, language, and art.

Robert S. de Ropp (scientist, humanitarian, and author), who had spent time with Huxley in England in the 1930s, connected with him again in the U.S. in the early 1960s and wrote that "the enormous intellect, the beautifully modulated voice, the gentle objectivity, all were unchanged. He was one of the most highly civilized human beings I had ever met."

Late-in-life perspectives
Biographer Harold H. Watts wrote that Huxley's writings in the "final and extended period of his life" are "the work of a man who is meditating on the central problems of many modern men". Huxley had deeply felt apprehensions about the future the developed world might make for itself. From these, he made some warnings in his writings and talks. In a 1958 televised interview conducted by journalist Mike Wallace, Huxley outlined several major concerns: the difficulties and dangers of world overpopulation; the tendency towards distinctly hierarchical social organisation; the crucial importance of evaluating the use of technology in mass societies susceptible to persuasion; the tendency to promote modern politicians to a naive public as well-marketed commodities. In a December 1962 letter to brother Julian, summarizing a paper he had presented in Santa Barbara, he wrote, "What I said was that if we didn't pretty quickly start thinking of human problems in ecological terms rather than in terms of power politics we should very soon be in a bad way."

Huxley's engagement with Eastern wisdom traditions was entirely compatible with a strong appreciation of modern science. Biographer Milton Birnbaum wrote that Huxley "ended by embracing both science and Eastern religion". In his last book, Literature and Science, Huxley wrote that "The ethical and philosophical implications of modern science are more Buddhist than Christian...." In "A Philosopher's Visionary Prediction", published one month before he died, Huxley endorsed training in general semantics and "the nonverbal world of culturally uncontaminated consciousness", writing that "We must learn how to be mentally silent, we must cultivate the art of pure receptivity.... [T]he individual must learn to decondition himself, must be able to cut holes in the fence of verbalized symbols that hems him in."

Spiritual views
Huxley described himself as agnostic, a word coined by his grandfather Thomas Henry Huxley, a scientist who championed the scientific method and was a major supporter of Darwin's theories, also a person who personally believed in God. This is the definition he gave, “…it is wrong for a man to say that he is certain of the objective truth of any proposition unless he can produce evidence which logically justifies that certainty.” Aldous Huxley's agnosticism, together with his speculative propensity, made it difficult for him fully embrace any form of institutionalised religion. Over the last 30 years of his life, he accepted and wrote about concepts found in Vedanta and was a leading advocate of the Perennial Philosophy, which holds that the same metaphysical truths are found in all the major religions of the world.

In the 1920s, Huxley was skeptical of religion, "Earlier in his career he had rejected mysticism, often poking fun at it in his novels [...]" Gerald Heard became an influential friend of Huxley, and since the mid-1920s had been exploring Vedanta, as a way of understanding individual human life and the individual's relationship to the universe. Heard and Huxley both saw the political implications of Vedanta, which could help bring about peace, specifically that there is an underlying reality that all humans and the universe are a part of. In the 1930s, Huxley and Gerald Heard both became active in the effort to avoid another world war, writing essays and eventually publicly speaking in support of the Peace Pledge Union. But, they remained frustrated by the conflicting goals of the political left – some favoring pacifism (as did Huxley and Heard), while other wanting to take up arms against fascism in the Spanish Civil War.

After joining the PPU, Huxley expressed his frustration with politics in a letter from 1935, “…the thing finally resolves itself into a religious problem — an uncomfortable fact which one must be prepared to face and which I have come during the last year to find it easier to face.” Huxley and Heard turned their attention to addressing the big problems of the world through transforming the individual, "[...] a forest is only as green as the individual trees of the forest is green [...]" This was the genesis of the Human Potential Movement, that gained traction in the 1960s.

In the late 1930s, Huxley and Heard immigrated to the United States, and beginning in 1939 and continuing until his death in 1963, Huxley had an extensive association with the Vedanta Society of Southern California, founded and headed by Swami Prabhavananda. Together with Gerald Heard, Christopher Isherwood and other followers, he was initiated by the Swami and was taught meditation and spiritual practices. From 1941 until 1960, Huxley contributed 48 articles to Vedanta and the West, published by the society. He also served on the editorial board with Isherwood, Heard, and playwright John Van Druten from 1951 through 1962.

In 1942 The Gospel of Ramakrishna was published by the Ramakrishna-Vivekananda Center in New York. The book was translated by Swami Nikhilananda, with help from Joseph Campbell and Margaret Woodrow Wilson, daughter of US president Woodrow Wilson. Aldous Huxley wrote in the Foreward, "...a book unique, so far as my knowledge goes, in the literature of hagiography. Never have the small events of a contemplative's daily life been described with such a wealth of intimate detail. Never have the casual and unstudied utterances of a great religious teacher been set down with so minute a fidelity."

In 1944, Huxley wrote the introduction to the Bhagavad Gita – The Song of God, translated by Swami Prabhavananda and Christopher Isherwood, which was published by the Vedanta Society of Southern California. As an advocate of the perennial philosophy, Huxley was drawn to the Gita, as he explained in the Introduction, written during WWII, when it was still not clear who would win:

"The Bhagavad Gita is perhaps the most systematic scriptural statement of the Perennial Philosophy. To a world at war, a world that, because it lacks the intellectual and spiritual prerequisites to peace, can only hope to patch up some kind of precarious armed truce, it stands pointing, clearly and unmistakably, to the only road of escape from the self–imposed necessity of self–destruction."

As a means of personally realizing the "divine Reality", he described a "Minimum Working Hypothesis" in the Introduction to Swami Prabhavananda's and Christopher Isherwood's translation of the Bhagavad Gita and in a free-standing essay in Vedanta and the West, a publication of Vedanta Press. This is the outline, that Huxley elaborates on in the article:

"For those of us who are not congenitally the members of an organized church, who have found that humanism and nature-worship are not enough, who are not content to remain in the darkness of ignorance, the squalor of vice or the other squalor of respectability, the minimum working hypothesis would seem to run to about this: That there is a Godhead, Ground, Brahman, Clear Light of the Void, which is the unmanifested principle of all manifestations. That the Ground is at once transcendent and immanent. That it is possible for human beings to love, know and, from virtually, to become actually identical with the divine Ground. That to achieve this unitive knowledge of the Godhead is the final end and purpose of human existence. That there is a Law or Dharma which must be obeyed, a Tao or Way which must be followed, if men are to achieve their final end."

For Huxley, one of the attractive features of Vedanta is that it provided an historic and established philosophy and practice that embraced the Perennial Philosophy; that there is a commonality of experiences across all the mystical branches of the world’s religions. Huxley wrote in the introduction of his book The Perennial Philosophy:

"The Perennial Philosophy is primarily concerned with the one, divine Reality substantial to the manifold world of things and lives and minds. But the nature of this one Reality is such that it cannot be directly and immediately apprehended except by those who have chosen to fulfill certain conditions, making themselves loving, pure in heart, and poor in spirit."

Huxley also occasionally lectured at the Hollywood and Santa Barbara Vedanta temples. Two of those lectures have been released on CD: Knowledge and Understanding and Who Are We? from 1955.

Many of Huxley's contemporaries and critics were disappointed by Huxley's turn to mysticism; Isherwood describes in his diary how he had to explain the criticism to Huxley's widow, Laura:

"[December 11, 1963, a few weeks after Aldous Huxley’s death] The publisher had suggested John Lehmann should write the biography. Laura [Huxley] asked me what I thought of the idea, so I had to tell her that John disbelieves in, and is aggressive toward, the metaphysical beliefs that Aldous held. All he would describe would be a clever young intellectual who later was corrupted by Hollywood and went astray after spooks."

Psychedelic drug use and mystical experiences
In early 1953, Huxley had his first experience with the psychedelic drug mescaline. Huxley had initiated a correspondence with Doctor Humphry Osmond, a British psychiatrist then employed in a Canadian institution, and eventually asked him to supply a dose of mescaline; Osmond obliged and supervised Huxley's session in southern California. After the publication of The Doors of Perception, in which he recounted this experience, Huxley and Swami Prabhavananda disagreed about the meaning and importance of the psychedelic drug experience, which may have caused the relationship to cool, but Huxley continued to write articles for the society's journal, lecture at the temple, and attend social functions. Huxley later had an experience on mescaline that he considered more profound than those detailed in The Doors of Perception.

Huxley wrote that "The mystical experience is doubly valuable; it is valuable because it gives the experiencer a better understanding of himself and the world and because it may help him to lead a less self-centered and more creative life."

Having tried LSD in the 1950s, he became an advisor to Timothy Leary and Richard Alpert in their early-1960s research work with psychedelic drugs at Harvard. Personality differences led Huxley to distance himself from Leary, when Huxley grew concerned that Leary had become too keen on promoting the drugs rather indiscriminately, even playing the rebel with a fondness for publicity.

Eyesight
Differing accounts exist about the details of the quality of Huxley's eyesight at specific points in his life. Circa 1939, Huxley encountered the Bates method, in which he was instructed by Margaret Darst Corbett. In 1940, Huxley relocated from Hollywood to a 40 acre ranchito in the high desert hamlet of Llano, California, in northern Los Angeles County. Huxley then said that his sight improved dramatically with the Bates method and the extreme and pure natural lighting of the southwestern American desert. He reported that, for the first time in more than 25 years, he was able to read without glasses and without strain. He even tried driving a car along the dirt road beside the ranch. He wrote a book about his experiences with the Bates method, The Art of Seeing, which was published in 1942 (U.S.), 1943 (UK). The book contained some generally disputed theories, and its publication created a growing degree of popular controversy about Huxley's eyesight.

It was, and is, widely believed that Huxley was nearly blind since the illness in his teens, despite the partial recovery that had enabled him to study at Oxford. For example, some ten years after publication of The Art of Seeing, in 1952, Bennett Cerf was present when Huxley spoke at a Hollywood banquet, wearing no glasses and apparently reading his paper from the lectern without difficulty: "Then suddenly he faltered—and the disturbing truth became obvious. He wasn't reading his address at all. He had learned it by heart. To refresh his memory he brought the paper closer and closer to his eyes. When it was only an inch or so away he still couldn't read it, and had to fish for a magnifying glass in his pocket to make the typing visible to him. It was an agonising moment."

Brazilian author João Ubaldo Ribeiro, who as a young journalist spent several evenings in the Huxleys' company in the late 1950s, wrote that Huxley had said to him, with a wry smile: "I can hardly see at all. And I don't give a damn, really."

On the other hand, Huxley's second wife Laura later emphasised in her biographical account, This Timeless Moment: "One of the great achievements of his life: that of having regained his sight." After revealing a letter she wrote to the Los Angeles Times disclaiming the label of Huxley as a "poor fellow who can hardly see" by Walter C. Alvarez, she tempered her statement: "Although I feel it was an injustice to treat Aldous as though he were blind, it is true there were many indications of his impaired vision. For instance, although Aldous did not wear glasses, he would quite often use a magnifying lens." Laura Huxley proceeded to elaborate a few nuances of inconsistency peculiar to Huxley's vision. Her account, in this respect, agrees with the following sample of Huxley's own words from The Art of Seeing: "The most characteristic fact about the functioning of the total organism, or any part of the organism, is that it is not constant, but highly variable." Nevertheless, the topic of Huxley's eyesight has continued to endure similar, significant controversy.

American popular science author Steven Johnson, in his book Mind Wide Open, quotes Huxley about his difficulties with visual encoding: "I am and, for as long as I can remember, I have always been a poor visualizer. Words, even the pregnant words of poets, do not evoke pictures in my mind. No hypnagogic visions greet me on the verge of sleep. When I recall something, the memory does not present itself to me as a vividly seen event or object. By an effort of the will, I can evoke a not very vivid image of what happened yesterday afternoon ..."

Personal life
Huxley married on 10 July 1919 Maria Nys (10 September 1899 – 12 February 1955), a Belgian epidemiologist from Bellem, a village near Aalter, he met at Garsington, Oxfordshire, in 1919. They had one child, Matthew Huxley (19 April 1920 – 10 February 2005), who had a career as an author, anthropologist, and prominent epidemiologist. In 1955, Maria Huxley died of cancer.

In 1956, Huxley married Laura Archera (1911–2007), also an author, as well as a violinist and psychotherapist. She wrote This Timeless Moment, a biography of Huxley. She told the story of their marriage through Mary Ann Braubach's 2010 documentary, Huxley on Huxley.

Huxley was diagnosed with laryngeal cancer in 1960; in the years that followed, with his health deteriorating, he wrote the utopian novel Island, and gave lectures on "Human Potentialities" both at the UCSF Medical Center and at the Esalen Institute. These lectures were fundamental to the beginning of the Human Potential Movement.

Huxley was a close friend of Jiddu Krishnamurti and Rosalind Rajagopal, and was involved in the creation of the Happy Valley School, now Besant Hill School, of Happy Valley, in Ojai, California.

The most substantial collection of Huxley's few remaining papers, following the destruction of most in the 1961 Bel Air Fire, is at the Library of the University of California, Los Angeles. Some are also at the Stanford University Libraries.

On 9 April 1962 Huxley was informed he was elected Companion of Literature by the Royal Society of Literature, the senior literary organisation in Britain, and he accepted the title via letter on 28 April 1962. The correspondence between Huxley and the society is kept at the Cambridge University Library. The society invited Huxley to appear at a banquet and give a lecture at Somerset House, London, in June 1963. Huxley wrote a draft of the speech he intended to give at the society; however, his deteriorating health meant he was not able to attend.

Death
In 1960, Huxley was diagnosed with oral cancer and for the next three years his health steadily declined. On November 4th, 1963, less than three weeks before Huxley's death, author Christopher Isherwood, a friend of 25 years, visited in Cedars Sinai Hospital and wrote his impressions:

"I came away with the picture of a great noble vessel sinking quietly into the deep; many of its delicate marvelous mechanisms still in perfect order, all its lights still shining."

At home on his deathbed, unable to speak owing to cancer that had metastasized, Huxley made a written request to his wife Laura for "LSD, 100 μg, intramuscular." According to her account of his death in This Timeless Moment, she obliged with an injection at 11:20 a.m. and a second dose an hour later; Huxley died aged 69, at 5:20 p.m. PST on 22 November 1963.

Media coverage of Huxley's death, along with that of fellow British author C. S. Lewis, was overshadowed by the assassination of John F. Kennedy on the same day, less than seven hours before Huxley's death. In a 2009 article for New York magazine titled "The Eclipsed Celebrity Death Club", Christopher Bonanos wrote:

"The championship trophy for badly timed death, though, goes to a pair of British writers. Aldous Huxley, the author of Brave New World, died the same day as C. S. Lewis, who wrote the Chronicles of Narnia series. Unfortunately for both of their legacies, that day was November 22, 1963, just as John Kennedy's motorcade passed the Texas School Book Depository. Huxley, at least, made it interesting: At his request, his wife shot him up with LSD a couple of hours before the end, and he tripped his way out of this world."

This coincidence served as the basis for Peter Kreeft's book Between Heaven and Hell: A Dialog Somewhere Beyond Death with John F. Kennedy, C. S. Lewis, & Aldous Huxley, which imagines a conversation among the three men taking place in Purgatory following their deaths.

Huxley's memorial service took place in London in December 1963; it was led by his elder brother Julian. On 27 October 1971, his ashes were interred in the family grave at the Watts Cemetery, home of the Watts Mortuary Chapel in Compton, Guildford, Surrey, England.

Huxley had been a long-time friend of Russian composer Igor Stravinsky, who dedicated his last orchestral composition to Huxley. What became Variations: Aldous Huxley in memoriam was begun in July 1963, completed in October 1964, and premiered by the Chicago Symphony Orchestra on 17 April 1965.

Awards

 * 1939: James Tait Black Memorial Prize (for After Many a Summer Dies the Swan).
 * 1959: American Academy of Arts and Letters Award of Merit (for Brave New World).
 * 1962: Companion of Literature (Royal Society of Literature)

Commemoration
In 2021, Huxley was one of six British writers commemorated on a series of UK postage stamps issued by Royal Mail to celebrate British science fiction. One classic science fiction novel from each author was depicted, with Brave New World chosen to represent Huxley.

title: Aldous Huxley


text:
Ada

Ada may refer to:

Arts and entertainment

 * Ada or Ardor: A Family Chronicle, a novel by Vladimir Nabokov

Film and television

 * Ada TV, a television channel in Northern Cyprus
 * Ada (1961 film), a 1961 film by Daniel Mann
 * Ada (2019 film), a short biopic about Ada Lovelace
 * Ada... A Way of Life, a 2008 Bollywood musical by Tanvir Ahmed
 * Ada (dog actor), a dog that played Colin on the sitcom Spaced
 * Ada, a character in 1991 movie Armour of God II: Operation Condor

Africa

 * Ada Foah, a town in Ghana
 * Ada (Ghana parliament constituency)
 * Ada, Osun, a town in Nigeria

Asia

 * Ada, Urmia, a village in West Azerbaijan Province, Iran
 * Ada, Karaman, a village in Karaman Province, Turkey

Europe

 * Ada, Bosnia and Herzegovina, a village
 * Ada, Croatia, a village
 * Ada, Serbia, a town and municipality
 * Ada Ciganlija or Ada, a river island artificially turned into a peninsula in Belgrade, Serbia

United States

 * Ada, Alabama, an unincorporated community
 * Ada County, Idaho
 * Ada, Kansas, an unincorporated community
 * Ada Township, Michigan
 * Ada, Minnesota, a city
 * Ada Township, Dickey County, North Dakota
 * Ada, Ohio, a village
 * Ada, Oklahoma, a city
 * Ada, Oregon, an unincorporated community
 * Ada Township, Perkins County, South Dakota
 * Ada, West Virginia, an unincorporated community
 * Ada, Wisconsin, an unincorporated community
 * Mount Ada, a mountain in Alaska

Elsewhere

 * Ada River (disambiguation), various rivers
 * 523 Ada, an asteroid

Science and technology

 * List of storms named Ada
 * Ada, the cryptocurrency of the Cardano blockchain platform

Biology

 * Ada (plant), a genus of orchids
 * Adenosine deaminase, an enzyme involved in purine metabolism
 * Ada (protein), an enzyme induced by treatment of bacterial cells

Computing

 * Ada (programming language), programming language based on Pascal
 * Ada (computer virus)

Schools

 * Ada, the National College for Digital Skills, a further education college in Tottenham Hale, London
 * Ada High School (Ohio), US
 * Ada Independent School District, Oklahoma, US

Transportation

 * Ada Air, a regional airline based in Tirana, Albania
 * Francisco C. Ada Airport, Saipan Island, Northern Mariana Islands
 * SS Ada (1905), a cargo vessel built for the London and South Western Railway
 * Ada (ship), a wooden ketch, wrecked near Newcastle, New South Wales, Australia
 * Ada-class corvette, a class of anti-submarine corvettes developed by Turkey

People

 * Ada (name), a feminine given name and a surname, including a list of people and fictional characters
 * Ada Lovelace (1815–1852), computer scientist sometimes regarded as the first computer programmer
 * Ada of Caria (fl. 377 – 326 BCE), satrap of ancient Caria and adoptive mother of Alexander the Great

Other uses

 * Ada (food), a traditional Kerala delicacy
 * Ada Bridge, Belgrade, Serbia
 * Dangme language (ISO 639-2 and 639-3 code: ada), spoken in Ghana
 * Ada Health, a German medical technology company

title: Ada