[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:07.13,0:00:13.47,Default,,0000,0000,0000,,In 1845, Ireland's vast potato fields\Nwere struck by an invasive fungal disease
Dialogue: 0,0:00:13.47,0:00:17.28,Default,,0000,0000,0000,,that rapidly infested this staple crop.
Dialogue: 0,0:00:17.28,0:00:19.26,Default,,0000,0000,0000,,The effect was devestating.
Dialogue: 0,0:00:19.26,0:00:21.62,Default,,0000,0000,0000,,One million people died of famine,
Dialogue: 0,0:00:21.62,0:00:25.83,Default,,0000,0000,0000,,and over a million more were forced\Nto leave Ireland.
Dialogue: 0,0:00:25.83,0:00:31.87,Default,,0000,0000,0000,,Nowadays, we avoid such agricultural\Ncatastrophes with the help of pesticides.
Dialogue: 0,0:00:31.87,0:00:35.64,Default,,0000,0000,0000,,Those are a range of manmade chemicals\Nthat control insects,
Dialogue: 0,0:00:35.64,0:00:37.22,Default,,0000,0000,0000,,unwanted weeds,
Dialogue: 0,0:00:37.22,0:00:38.30,Default,,0000,0000,0000,,funguses,
Dialogue: 0,0:00:38.30,0:00:39.07,Default,,0000,0000,0000,,rodents,
Dialogue: 0,0:00:39.07,0:00:40.20,Default,,0000,0000,0000,,and bacteria\N
Dialogue: 0,0:00:40.20,0:00:42.27,Default,,0000,0000,0000,,that may threaten our food supply.
Dialogue: 0,0:00:42.27,0:00:44.75,Default,,0000,0000,0000,,They've become an essential part\Nof our food system.
Dialogue: 0,0:00:44.75,0:00:49.09,Default,,0000,0000,0000,,As populations have grown,\Nmonoculture, single crop farming,
Dialogue: 0,0:00:49.09,0:00:51.71,Default,,0000,0000,0000,,has helped us feed people efficiently.
Dialogue: 0,0:00:51.71,0:00:57.04,Default,,0000,0000,0000,,But it's also left our food\Nvulnerable to extensive attack by pests.
Dialogue: 0,0:00:57.04,0:01:00.67,Default,,0000,0000,0000,,In turn, we've become more dependent\Non pesticides.
Dialogue: 0,0:01:00.67,0:01:06.50,Default,,0000,0000,0000,,Today, we annually shower over 5 billion\Npounds of pesticides across the Earth
Dialogue: 0,0:01:06.50,0:01:09.20,Default,,0000,0000,0000,,to control these unwanted visitors.
Dialogue: 0,0:01:09.20,0:01:12.07,Default,,0000,0000,0000,,The battle against pests,\Nespecially insects,
Dialogue: 0,0:01:12.07,0:01:15.03,Default,,0000,0000,0000,,has marked agriculture's long history.
Dialogue: 0,0:01:15.03,0:01:16.91,Default,,0000,0000,0000,,Records from thousands of years ago
Dialogue: 0,0:01:16.91,0:01:21.35,Default,,0000,0000,0000,,suggest that humans actively burned\Nsome of their crops after harvest
Dialogue: 0,0:01:21.35,0:01:23.80,Default,,0000,0000,0000,,to rid them of pests.
Dialogue: 0,0:01:23.80,0:01:29.12,Default,,0000,0000,0000,,There's even evidence from ancient times\Nthat we recruited other insects to help.
Dialogue: 0,0:01:29.12,0:01:34.62,Default,,0000,0000,0000,,In 300 A.D., Chinese farmers specially\Nbred ferocious predatory ants
Dialogue: 0,0:01:34.62,0:01:39.30,Default,,0000,0000,0000,,in orange orchards\Nto protect the trees from other bugs.
Dialogue: 0,0:01:39.30,0:01:41.17,Default,,0000,0000,0000,,Later, as large-scale farming spread,
Dialogue: 0,0:01:41.17,0:01:47.13,Default,,0000,0000,0000,,we began sprinkling arsenic, lead,\Nand copper treatments on crops.
Dialogue: 0,0:01:47.13,0:01:51.01,Default,,0000,0000,0000,,But these were incredibly toxic\Nto humans as well.
Dialogue: 0,0:01:51.01,0:01:54.37,Default,,0000,0000,0000,,As our demand for more, \Nsafer produce increased,
Dialogue: 0,0:01:54.37,0:01:56.98,Default,,0000,0000,0000,,so did the need for effective chemicals
Dialogue: 0,0:01:56.98,0:02:00.22,Default,,0000,0000,0000,,that could control pests\Non a grander scale.
Dialogue: 0,0:02:00.22,0:02:04.63,Default,,0000,0000,0000,,This ushered in the era \Nof chemical pesticides.
Dialogue: 0,0:02:04.63,0:02:08.90,Default,,0000,0000,0000,,In 1948, a Swiss chemist named\NPaul Hermann Müller
Dialogue: 0,0:02:08.90,0:02:12.00,Default,,0000,0000,0000,,was awarded a Nobel Prize \Nfor his discovery
Dialogue: 0,0:02:12.00,0:02:18.44,Default,,0000,0000,0000,,of dichlorodiphenyltrichloroethane,\Nalso known as DDT.
Dialogue: 0,0:02:18.44,0:02:23.26,Default,,0000,0000,0000,,This new molecule had unparalleled power\Nto control many insect species
Dialogue: 0,0:02:23.26,0:02:28.21,Default,,0000,0000,0000,,until the 1950s,\Nwhen insects became resistant to it.
Dialogue: 0,0:02:28.21,0:02:33.55,Default,,0000,0000,0000,,Worse, the chemical actually drove\Ndramatic declines in bird populations,
Dialogue: 0,0:02:33.55,0:02:35.37,Default,,0000,0000,0000,,poisoned water sources,
Dialogue: 0,0:02:35.37,0:02:40.57,Default,,0000,0000,0000,,and was eventually found to cause\Nlong-term health problems in humans.
Dialogue: 0,0:02:40.57,0:02:44.99,Default,,0000,0000,0000,,By 1972, DDT had been banned\Nin the United States,
Dialogue: 0,0:02:44.99,0:02:48.94,Default,,0000,0000,0000,,and yet traces still linger\Nin the environment today.
Dialogue: 0,0:02:48.94,0:02:52.45,Default,,0000,0000,0000,,Since then, chemists have been searching\Nfor alternatives.
Dialogue: 0,0:02:52.45,0:02:56.49,Default,,0000,0000,0000,,With each new wave of inventions,\Nthey've encountered the same obstacle -
Dialogue: 0,0:02:56.49,0:02:58.74,Default,,0000,0000,0000,,rapid species evolution.
Dialogue: 0,0:02:58.74,0:03:01.33,Default,,0000,0000,0000,,As pesticides destroy pest populations,
Dialogue: 0,0:03:01.33,0:03:05.72,Default,,0000,0000,0000,,they leave behind \Nonly the most resistant individuals.
Dialogue: 0,0:03:05.72,0:03:08.82,Default,,0000,0000,0000,,They then pass on their \Npesticide-resisting genes
Dialogue: 0,0:03:08.82,0:03:10.64,Default,,0000,0000,0000,,to the next generation.
Dialogue: 0,0:03:10.64,0:03:13.19,Default,,0000,0000,0000,,That's lead to the rise of super bugs,
Dialogue: 0,0:03:13.19,0:03:15.61,Default,,0000,0000,0000,,such as the Colorado potato beetle,
Dialogue: 0,0:03:15.61,0:03:19.38,Default,,0000,0000,0000,,which is resistant to over \N50 different insecticides.
Dialogue: 0,0:03:19.38,0:03:23.83,Default,,0000,0000,0000,,Another downside is that other bugs\Nget caught in the crossfire.
Dialogue: 0,0:03:23.83,0:03:29.45,Default,,0000,0000,0000,,Some of these are helpful predators\Nof plant pests or vital pollinators,
Dialogue: 0,0:03:29.45,0:03:34.30,Default,,0000,0000,0000,,so erasing them from agriculture\Nwipes out their benefits, too.
Dialogue: 0,0:03:34.30,0:03:36.34,Default,,0000,0000,0000,,Pesticides have improved over time
Dialogue: 0,0:03:36.34,0:03:39.32,Default,,0000,0000,0000,,and are currently regulated by strict\Nsafety standards,
Dialogue: 0,0:03:39.32,0:03:42.90,Default,,0000,0000,0000,,but they still have the potential\Nto pollute soil and water,
Dialogue: 0,0:03:42.90,0:03:44.31,Default,,0000,0000,0000,,impact wildlife,
Dialogue: 0,0:03:44.31,0:03:46.18,Default,,0000,0000,0000,,and even harm us.
Dialogue: 0,0:03:46.18,0:03:50.74,Default,,0000,0000,0000,,So considering all these risks,\Nwhy do we continue using pesticides?
Dialogue: 0,0:03:50.74,0:03:52.14,Default,,0000,0000,0000,,Although they're imperfect,
Dialogue: 0,0:03:52.14,0:03:57.16,Default,,0000,0000,0000,,they currently may be our best bet\Nagainst major agricultural disasters,
Dialogue: 0,0:03:57.16,0:03:59.96,Default,,0000,0000,0000,,not to mention mosquito-born diseases.
Dialogue: 0,0:03:59.96,0:04:04.84,Default,,0000,0000,0000,,Today, scientists are on a quest for\Nalternative pest control strategies
Dialogue: 0,0:04:04.84,0:04:06.98,Default,,0000,0000,0000,,that balance the demands\Nof food production
Dialogue: 0,0:04:06.98,0:04:09.40,Default,,0000,0000,0000,,with environmental concerns.
Dialogue: 0,0:04:09.40,0:04:12.84,Default,,0000,0000,0000,,Nature has become a major source\Nof inspiration,
Dialogue: 0,0:04:12.84,0:04:17.12,Default,,0000,0000,0000,,from natural plant and fungal chemicals\Nthat can repel or attract insects,
Dialogue: 0,0:04:17.12,0:04:20.92,Default,,0000,0000,0000,,to recruiting other insects \Nas crop bodyguards.
Dialogue: 0,0:04:20.92,0:04:24.88,Default,,0000,0000,0000,,We're also turning to high-tech solutions,\Nlike drones.
Dialogue: 0,0:04:24.88,0:04:26.93,Default,,0000,0000,0000,,Programmed to fly over crops,
Dialogue: 0,0:04:26.93,0:04:29.76,Default,,0000,0000,0000,,these machines can use \Ntheir sensors and GPS
Dialogue: 0,0:04:29.76,0:04:32.45,Default,,0000,0000,0000,,to carry out more targeted sprays
Dialogue: 0,0:04:32.45,0:04:36.30,Default,,0000,0000,0000,,that limit a pesticide's wider \Nenvironmental impact.
Dialogue: 0,0:04:36.30,0:04:38.83,Default,,0000,0000,0000,,With a combination \Nof biological understanding,
Dialogue: 0,0:04:38.83,0:04:40.46,Default,,0000,0000,0000,,environmental awareness,
Dialogue: 0,0:04:40.46,0:04:42.38,Default,,0000,0000,0000,,and improved technologies,
Dialogue: 0,0:04:42.38,0:04:46.63,Default,,0000,0000,0000,,we have a better chance of finding\Na holistic solution to pests.
Dialogue: 0,0:04:46.63,0:04:50.62,Default,,0000,0000,0000,,Chemical pesticides may never shake\Ntheir controversial reputation,
Dialogue: 0,0:04:50.62,0:04:51.96,Default,,0000,0000,0000,,but with their help,
Dialogue: 0,0:04:51.96,0:04:54.86,Default,,0000,0000,0000,,we can ensure that \Nagricultural catastrophes
Dialogue: 0,0:04:54.86,0:04:56.92,Default,,0000,0000,0000,,stay firmly in our past.