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  • The development of ecology revealed a deeply connected world: we all inhabit one big biosphereone

  • big house.

  • We share one hydrosphere, one atmosphere

  • You get the idea.

  • But the flip side of finding this connection was learning about various kinds of environmental

  • collapse, already in motion.

  • We share one fragile house.

  • We've said that sciences generally move from understanding natural phenomena to controlling

  • them.

  • Today, we'll examine scientific efforts to control the whole world, AKA capital-N

  • Nature.

  • Some have saved livesbut there are also downsides, frequently devastating.

  • [Intro Music Plays]

  • During the Cold War, attempts to control Nature by technological means involved both Soviet

  • and American plans for weather control

  • in part because each side worried that the other would figure it out first.

  • Spoiler Alert: neither did.

  • The U.S. conducted one secret rainmaking project, Operation Popeye, during the Vietnam War.

  • They ineffectively tried to make the monsoon season last longer in Southeast Asia, hampering

  • the North Vietnamese army's movements by deteriorating roads and bridges through flooding.

  • That's James Bond villain stuff!

  • The U.S. also carried out an operation at home called Project Stormfury from 1962 to

  • 1983,

  • seeding dangerous tropical storms with silver iodide in order to freeze some of the water

  • in them and slow them down, making them less dangerous.

  • This didn't work well in practice, but the experimental flights were valuable to meteorology.

  • Other grand-scale engineering projects focused on power and agriculture.

  • These included many irrigation canals and gigantic dams, like the Aswan High Dam in

  • Egypt, built between 1960 and 1970.

  • These projects allowed people in dry regions or ones subject to seasonal flooding to have

  • more control over when they planted, and to grow more harvests per year.

  • In the United States, the Reclamation Service, later the Bureau of Reclamation, worked starting

  • in 1902 to irrigate the Western plains.

  • Today, that Bureau is the largest wholesaler of water in the U.S.

  • Overall, across industrial societies, agriculture changed a lot as engineers developed machines

  • like tractors,

  • chemists created new fertilizers and pesticides, and plant geneticists bred hybrid seeds.

  • Plants need the nutrient nitrogen to grow.

  • But plants can't “fixtheir own nitrogen from air, so they need bacteria, or human-made

  • fertilizers like ammonia, to do it for them.

  • And in the early 1900s, German chemists Fritz Haber and Carl Bosch developed a way to take

  • nitrogen right from the air!

  • This seemed like a big win.

  • Any industrial society could use the HaberBosch process for synthetic nitrogen fixation to

  • make millions of tons of fertilizer and grow more crops.

  • And synthetic ammonia from the process was also used to make nitric acid, which was necessary

  • to make explosives.

  • So again, war and professional science were tightly linked.

  • But the bigger problems, long term, were environmental.

  • The HaberBosch process requires fossil fuels like oil or natural gas to work.

  • Which seemed fine: industrialists didn't know that burning these fuels would disrupt

  • the earth's climate cycles.

  • A more obvious problem is runoff: to make plants take up lots of nitrogen, industrial

  • farming treats them with more fertilizer than they need.

  • Rain washes the leftover fertilizer into waterways, leading to eutrophication, or too many nutrients

  • in the water.

  • This leads to a build-up of algae, which use up the oxygen in the water, making it deadly

  • for fish.

  • Another seemingly big win with unintended consequences was an improvement in staple

  • crops.

  • In the 1930s, after decades of research, agricultural scientists in the U.S. rolled out hybrid crop

  • varieties.

  • These crosses ofpurestrains produced much higher yields.

  • But farmers started using only these seeds.

  • Commercial fields became monoculture, orone-plant.”

  • This means fewer plants are commercially available today.

  • And pests can more easily wipe out any one plant.

  • This is the opposite of growing many plants together, or polyculture, which can help restore

  • nutrients to soil without synthetic chemicals.

  • So on the one hand, synthetic fertilizers and hybrid crops seemed like easy wins.

  • On the other hand, there were negative long-term consequences.

  • On the, uh, third hand, even these advancements didn't prevent environmental problems and

  • growing fears that agricultural innovation just couldn't keep up with rapid population

  • growth.

  • For example, part of the U.S. experienced severe droughts in the 1930s and was farmed

  • in unsustainable ways.

  • This led to massive dust storms, collectively called the Dust Bowl, which forced many farmers

  • to abandon their farmsduring the Great Depression.

  • And this was the United States!

  • Most of the world's farmers remained smallholders:

  • they worked plots of land smaller than ten hectares, largely without industrial machines.

  • Populations were growing, but storms and wars threatened to lead to famines.

  • So many scientists, taking a note from that crotchety preacher who inspired Darwin, Thomas

  • Malthus, wrote pessimistically about humanity's future.

  • Probably the most famous of theseneo-Malthusianthinkers was American biologist Paul Ehrlich,

  • whose 1968 bestseller, The Population Bomb, predicted that famines would soon kill millions

  • of people, especially in India.

  • Which didn't happen

  • Arguably the biggest example of humans controlling our environment was the Green Revolution in

  • the 1950s and 60s,

  • when crop yields went up for farmers in less industrialized countriesway up.

  • In one sense, it's a simple story of science, applied: scientists from rich countries offered

  • new techniques built on hybrid seeds.

  • In another sense, it's science in the service of politics.

  • This revolution was organized by International Agricultural Research Centers,

  • or IARCs, which were funded by federal grants from developed and developing countries, and

  • by private foundations like Rockefeller and Ford.

  • The IARCs believed that the best way to improve yields was through smart breeding.

  • They wanted to focus on breeding plants resistant to pests in specific areas.

  • And simultaneously, to make these plants take up more nitrogen and grow more edible material.

  • Lots of people were involved in this work, particularly in the U.S., Mexico, and India.

  • But people love heroes!

  • So Green Revolution stories often focus on American agronomist and plant geneticist Norman

  • Borlaugwho was, to be fair, an awesome scientist.

  • Introduce us, ThoughtBubble.

  • Borlaug joined the Rockefeller Foundation's group in Mexico in 1944.

  • He had never worked on wheat, maize, or beans before.

  • Aaand he didn't speak Spanish.

  • But, he eventually learned it and stayed ins He developed a hybrid wheat that withstands

  • a common fungus called rust blight.

  • How?

  • Lots of painstaking research into plant genetics, courtesy other geneticists, and lots of field

  • trials:

  • Borlaug took Norin 10—a wheat bred by Japanese scientist Gonjiro Inazuka

  • that was short but produced lots of food, if given lots of nitrogen and defended with

  • chemical pesticides

  • and bred a semi-dwarf wheat specifically for Mexican climates.

  • Starting around 1950, Mexican agriculture shifted toward high-yielding varieties of

  • wheat, synthetic nitrogen, and pesticides.

  • And this revolution in farming soon spread to Colombia, Chile, and India.

  • The Ford Foundation pushed the Indian government to adopt the same changes.

  • So Indian scientists worked with Mexican scientists, and hybrid semi-dwarf Mexican wheat seeds

  • were shipped to India in time for the 1963 planting season.

  • This lead to astounding growths in yield.

  • Also in the 1960s, an international team of scientists and farmers worked to develop a

  • new variety of high-yielding semi-dwarf rice called IR8—

  • sometimes calledmiracle rice.”

  • In 1971, the Rockefeller and Ford Foundations created the Consultative Group on International

  • Agricultural Research to further extend the IARC research.

  • Borlaug won the Nobel in 1970.

  • Buuutno Mexican, Indian, or Japanese scientists shared the prize.

  • Thanks, ThoughtBubble.

  • Meanwhile, with minimal support from the Soviet Union, the Maoist Chinese state fostered its

  • own scientific farming

  • including a system of experimental agricultural stations and hybrid sorghum and hybrid rice

  • varieties.

  • Agriculturally, the Green Revolution was an immediate success.

  • Thousands of tons of seeds moved from Mexico to India.

  • Food prices dropped.

  • India became a rice exporter and currently overproduces wheat.

  • But in the longer-term, the Green Revolution meant that way more farmers started practicing

  • monoculture, essentially betting their chips on a small number of hybrid crops.

  • Thousands of traditional varieties are no longer cultivated.

  • Only four cropswheat, maize, rice, and soyprovide more than half of our food today.

  • Socially, industrial farming requires investing in expensive equipment and hybrid seeds,

  • which aren't produced by the previous year's harvest.

  • This changed the business cycles of farmers.

  • Zooming out, the Green Revolution changed what defines a “modernsociety:

  • it now meant using synthetic nitrogen, pesticides, and tractors on large monoculture farms.

  • The idea of the Revolution had been to end hunger, and it probably prevented millions

  • from starvation.

  • But famine has always been linked to distribution, or the political

  • -economic process of moving food around, not only how much food is produced.

  • And the Green Revolution was also always about the United States flexing its scientific muscle

  • around the world,

  • buying allies with breadincluding India, the world's largest democracy.

  • AKA soft power!

  • Meanwhile, also in the 1950s and 60s, synthetic pesticides were used to control bugs that

  • spread human illnesses.

  • The most famous was dichlorodiphenyltrichloroethaneDDT

  • that was sprayed on fields, urban green spaces,

  • right on little kidspretty much everywhere.

  • It had seemingly miraculously dropped mosquito populations during World War II, helping fight

  • the spread of malaria and typhus.

  • Only it turned out that DDT, while not immediately toxic to humans, was toxic to lots of other

  • living things, like birds and fish.

  • And it wasn't good for humans in the long-run, either.

  • After years of careful researchall of which angered scientists working for the chemical

  • industry

  • American biologist and pioneering environmentalist Rachel Carson wrote a series of articles that

  • became the book Silent Spring in 1962.

  • She explained in simple, beautiful language how some kinds of synthetic pesticides work,

  • and why they are often a terrible idea.

  • With this book, along with her other books, numerous op-eds, and appearances, Carson helped

  • spark the modern environmentalism movement in the United States.

  • In addition to long-term effects, pesticides have also been involved in acute disasters.

  • In 1984, a Union Carbide India chemical plant in the city of Bhopal had a serious accident.

  • This plant produced the insecticide Sevin, using a highly toxic chemical called methyl

  • isocyanate gas.

  • The accident released thirty two tons of methyl isocyanate

  • Half a million people were exposed.

  • Four thousand people died immediately; twenty five hundred died that year.

  • Bhopal is widely regarded as the worst industrial disaster in history

  • Only two years later, in 1986, a nuclear reactor in Chernobyl melted down.

  • Clouds of radioactive material billowed across Europe, and then the world.

  • Conflicting, politically inflected epidemiological studies put the long-term casualties from

  • cancer due to Chernobyl

  • at anywhere between ten thousand and hundreds of thousands.

  • Socontrolling nature has not been a slam-dunk for humankind.

  • And most ofhumankindhad no say in these projects!

  • The effects, good or bad, just happened to them.

  • And this is still the case.

  • In fact, the Intergovernmental Panel on Climate Change warns that global food supplies are

  • in danger,

  • because staple crops like rice, wheat, and corn are now facing a slowdown in the rate

  • at which their yields go up.

  • Meaning, back to Malthus, we might soon have more hungry mouths than food, even if agronomists

  • keep making incremental gains.

  • So some serious scientists are returning to the idea of controlling the climate!

  • In 2006, Nobel-winning atmospheric scientist Paul Crutzen called for humanity to use geoengineering,

  • the modification of the climate, to keep our world habitable.

  • Next timewe'll look at control over living things at a different scale:

  • it's the characterization of DNA and the birth of biotechnology.

  • Crash Course History of Science is filmed in the Dr. Cheryl C. Kinney studio in Missoula,

  • Montana and it's made with the help of all this nice people and our animation team is

  • Thought Cafe.

  • Crash Course is a Complexly production.

  • If you wanna keep imagining the world complexly with us, you can check out some of our other

  • channels like Nature League, Sexplanations, and Scishow.

  • And, if you'd like to keep Crash Course free for everybody, forever, you can support

  • the series at Patreon; a crowdfunding platform that allows you to support the content you

  • love.

  • Thank you to all of our patrons for making Crash Course possible with their continued

  • support.

The development of ecology revealed a deeply connected world: we all inhabit one big biosphereone

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環境をコントロールする科学のクラッシュコースの歴史 #39 (Controlling the Environment: Crash Course History of Science #39)

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    林宜悉 に公開 2021 年 01 月 14 日
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