[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:06.97,0:00:08.83,Default,,0000,0000,0000,,We all know about the dinosaurs
Dialogue: 0,0:00:08.83,0:00:10.71,Default,,0000,0000,0000,,that once roamed the planet,
Dialogue: 0,0:00:10.71,0:00:12.97,Default,,0000,0000,0000,,but long after they went extinct,
Dialogue: 0,0:00:12.97,0:00:15.38,Default,,0000,0000,0000,,great beasts we call the megafauna
Dialogue: 0,0:00:15.38,0:00:17.96,Default,,0000,0000,0000,,lived on every continent.
Dialogue: 0,0:00:17.96,0:00:21.84,Default,,0000,0000,0000,,In the Americas, ground sloths the size of elephants
Dialogue: 0,0:00:21.84,0:00:24.22,Default,,0000,0000,0000,,pulled down trees with their claws.
Dialogue: 0,0:00:24.22,0:00:26.80,Default,,0000,0000,0000,,Saber-toothed cats the size of brown bears
Dialogue: 0,0:00:26.80,0:00:28.27,Default,,0000,0000,0000,,hunted in packs,
Dialogue: 0,0:00:28.27,0:00:30.30,Default,,0000,0000,0000,,but they were no match for short-faced bears,
Dialogue: 0,0:00:30.30,0:00:33.22,Default,,0000,0000,0000,,which stood thirteen feet on their hind legs,
Dialogue: 0,0:00:33.22,0:00:35.13,Default,,0000,0000,0000,,and are likely to have driven these cats
Dialogue: 0,0:00:35.13,0:00:36.69,Default,,0000,0000,0000,,away from their prey.
Dialogue: 0,0:00:36.69,0:00:39.61,Default,,0000,0000,0000,,There were armadillos as big as small cars,
Dialogue: 0,0:00:39.61,0:00:41.13,Default,,0000,0000,0000,,an eight foot beaver,
Dialogue: 0,0:00:41.13,0:00:44.32,Default,,0000,0000,0000,,and a bird with a 26 foot wingspan.
Dialogue: 0,0:00:44.32,0:00:46.91,Default,,0000,0000,0000,,Almost everywhere, the world's megafauna
Dialogue: 0,0:00:46.91,0:00:50.38,Default,,0000,0000,0000,,were driven to extinction, often by human hunters.
Dialogue: 0,0:00:50.38,0:00:54.30,Default,,0000,0000,0000,,Some species still survive in parts of Africa and Asia.
Dialogue: 0,0:00:54.30,0:00:59.00,Default,,0000,0000,0000,,In other places, you can still see the legacy of these great beasts.
Dialogue: 0,0:00:59.00,0:01:00.88,Default,,0000,0000,0000,,Most trees are able to resprout
Dialogue: 0,0:01:00.88,0:01:02.55,Default,,0000,0000,0000,,where their trunk is broken
Dialogue: 0,0:01:02.55,0:01:04.97,Default,,0000,0000,0000,,to withstand the loss of much of their bark
Dialogue: 0,0:01:04.97,0:01:07.80,Default,,0000,0000,0000,,and to survive splitting, twisting and trampling,
Dialogue: 0,0:01:07.80,0:01:12.13,Default,,0000,0000,0000,,partly because they evolved to survive attacks by elephants.
Dialogue: 0,0:01:12.13,0:01:14.63,Default,,0000,0000,0000,,The American pronghorn can run so fast
Dialogue: 0,0:01:14.63,0:01:17.80,Default,,0000,0000,0000,,because it evolved to escape the American cheetah.
Dialogue: 0,0:01:17.80,0:01:21.03,Default,,0000,0000,0000,,The surviving animals live in ghost ecosystems
Dialogue: 0,0:01:21.03,0:01:25.22,Default,,0000,0000,0000,,adapted to threats from species that no longer exist.
Dialogue: 0,0:01:25.22,0:01:28.38,Default,,0000,0000,0000,,Today, it may be possible to resurrect those ghosts,
Dialogue: 0,0:01:28.38,0:01:31.16,Default,,0000,0000,0000,,to bring back lost species using genetic material.
Dialogue: 0,0:01:31.16,0:01:33.22,Default,,0000,0000,0000,,For instance, there's been research in to
Dialogue: 0,0:01:33.22,0:01:36.72,Default,,0000,0000,0000,,cloning woolly mammoths from frozen remains.
Dialogue: 0,0:01:36.72,0:01:38.47,Default,,0000,0000,0000,,But even if it's not possible,
Dialogue: 0,0:01:38.47,0:01:41.34,Default,,0000,0000,0000,,we can still restore many of the ecosystems
Dialogue: 0,0:01:41.34,0:01:43.22,Default,,0000,0000,0000,,the world has lost.
Dialogue: 0,0:01:43.22,0:01:47.10,Default,,0000,0000,0000,,How? By making use of abandoned farms.
Dialogue: 0,0:01:47.10,0:01:49.13,Default,,0000,0000,0000,,As the market for food is globalized,
Dialogue: 0,0:01:49.13,0:01:51.97,Default,,0000,0000,0000,,infertile land becomes uncompetitive.
Dialogue: 0,0:01:51.97,0:01:54.19,Default,,0000,0000,0000,,Farmers in barren places can't compete
Dialogue: 0,0:01:54.19,0:01:57.38,Default,,0000,0000,0000,,with people growing crops on better land elsewhere.
Dialogue: 0,0:01:57.38,0:02:01.36,Default,,0000,0000,0000,,As a result, farming has started to retreat from many regions,
Dialogue: 0,0:02:01.36,0:02:03.99,Default,,0000,0000,0000,,and trees have started to return.
Dialogue: 0,0:02:03.99,0:02:07.12,Default,,0000,0000,0000,,One estimate claims that two-thirds of land in the US
Dialogue: 0,0:02:07.12,0:02:09.83,Default,,0000,0000,0000,,that was once forested but was cleared for farming
Dialogue: 0,0:02:09.83,0:02:11.63,Default,,0000,0000,0000,,has become forested again.
Dialogue: 0,0:02:11.63,0:02:13.83,Default,,0000,0000,0000,,Another estimate suggests that by 2030,
Dialogue: 0,0:02:13.83,0:02:16.17,Default,,0000,0000,0000,,an area in Europe the size of Poland
Dialogue: 0,0:02:16.17,0:02:18.30,Default,,0000,0000,0000,,will be vaccated by farmers.
Dialogue: 0,0:02:18.30,0:02:20.67,Default,,0000,0000,0000,,So even if we can't use DNA to bring back
Dialogue: 0,0:02:20.67,0:02:23.17,Default,,0000,0000,0000,,ground sloths and giant armadillos,
Dialogue: 0,0:02:23.17,0:02:25.51,Default,,0000,0000,0000,,we can restore bears, wolves, pumas
Dialogue: 0,0:02:25.51,0:02:27.47,Default,,0000,0000,0000,,lynx, moose and bison
Dialogue: 0,0:02:27.47,0:02:29.38,Default,,0000,0000,0000,,to the places where they used to live.
Dialogue: 0,0:02:29.38,0:02:32.02,Default,,0000,0000,0000,,Some of these animals can reshape their surroundings,
Dialogue: 0,0:02:32.02,0:02:35.52,Default,,0000,0000,0000,,creating conditions that allow other species to thrive.
Dialogue: 0,0:02:35.52,0:02:37.05,Default,,0000,0000,0000,,When wolves were reintroduced to
Dialogue: 0,0:02:37.05,0:02:39.94,Default,,0000,0000,0000,,the Yellowstone National Park in 1995,
Dialogue: 0,0:02:39.94,0:02:42.38,Default,,0000,0000,0000,,they quickly transformed the ecosystem.
Dialogue: 0,0:02:42.38,0:02:44.99,Default,,0000,0000,0000,,Where they reduced the numbers of overpopulated deer,
Dialogue: 0,0:02:44.99,0:02:47.07,Default,,0000,0000,0000,,vegetation began to recover.
Dialogue: 0,0:02:47.07,0:02:51.30,Default,,0000,0000,0000,,The height of some trees quintupled in just six years.
Dialogue: 0,0:02:51.30,0:02:54.63,Default,,0000,0000,0000,,As forests returned, so did songbirds.
Dialogue: 0,0:02:54.63,0:02:57.71,Default,,0000,0000,0000,,Beavers, which eat trees, multiplied in the rivers,
Dialogue: 0,0:02:57.71,0:02:59.58,Default,,0000,0000,0000,,and their dams provided homes
Dialogue: 0,0:02:59.58,0:03:04.05,Default,,0000,0000,0000,,for otters, muskrats, ducks, frogs and fish.
Dialogue: 0,0:03:04.05,0:03:06.63,Default,,0000,0000,0000,,The wolves killed coyotes, allowing rabbits
Dialogue: 0,0:03:06.63,0:03:08.43,Default,,0000,0000,0000,,and mice to increase,
Dialogue: 0,0:03:08.43,0:03:11.01,Default,,0000,0000,0000,,providing more food for hawks, weasels,
Dialogue: 0,0:03:11.01,0:03:12.93,Default,,0000,0000,0000,,foxes and badgers.
Dialogue: 0,0:03:12.93,0:03:15.77,Default,,0000,0000,0000,,Bald eagles and ravens fed on the carrion
Dialogue: 0,0:03:15.77,0:03:17.60,Default,,0000,0000,0000,,that the wolves abandoned.
Dialogue: 0,0:03:17.60,0:03:19.63,Default,,0000,0000,0000,,So did bears, which also ate the berries
Dialogue: 0,0:03:19.63,0:03:21.97,Default,,0000,0000,0000,,on the returning shrubs.
Dialogue: 0,0:03:21.97,0:03:23.97,Default,,0000,0000,0000,,Bison numbers rose as they browsed
Dialogue: 0,0:03:23.97,0:03:26.15,Default,,0000,0000,0000,,the revitalized forests.
Dialogue: 0,0:03:26.15,0:03:29.55,Default,,0000,0000,0000,,The wolves changed almost everything.
Dialogue: 0,0:03:29.55,0:03:32.38,Default,,0000,0000,0000,,This is an example of a trophic cascade,
Dialogue: 0,0:03:32.38,0:03:34.41,Default,,0000,0000,0000,,a change at the top of the food chain
Dialogue: 0,0:03:34.41,0:03:36.80,Default,,0000,0000,0000,,that tumbles all the way to the bottom,
Dialogue: 0,0:03:36.80,0:03:38.47,Default,,0000,0000,0000,,affecting every level.
Dialogue: 0,0:03:38.47,0:03:41.30,Default,,0000,0000,0000,,The discovery of widespread trophic cascades
Dialogue: 0,0:03:41.30,0:03:44.08,Default,,0000,0000,0000,,may be one of the most exciting scientific findings
Dialogue: 0,0:03:44.08,0:03:45.92,Default,,0000,0000,0000,,of the past half century.
Dialogue: 0,0:03:45.92,0:03:48.13,Default,,0000,0000,0000,,They tell us that ecosystems that have lost
Dialogue: 0,0:03:48.13,0:03:50.63,Default,,0000,0000,0000,,just one or two species of large animals
Dialogue: 0,0:03:50.63,0:03:53.22,Default,,0000,0000,0000,,can behave in radically different ways
Dialogue: 0,0:03:53.22,0:03:54.93,Default,,0000,0000,0000,,from those that retain them.
Dialogue: 0,0:03:54.93,0:03:56.85,Default,,0000,0000,0000,,All over the world, new movements are trying
Dialogue: 0,0:03:56.85,0:03:59.22,Default,,0000,0000,0000,,to catalyze the restoration of nature
Dialogue: 0,0:03:59.22,0:04:01.72,Default,,0000,0000,0000,,in a process called rewilding.
Dialogue: 0,0:04:01.72,0:04:04.52,Default,,0000,0000,0000,,This means undoing some of the damage we've caused,
Dialogue: 0,0:04:04.52,0:04:07.05,Default,,0000,0000,0000,,reestablishing species which have been driven out,
Dialogue: 0,0:04:07.05,0:04:08.74,Default,,0000,0000,0000,,and then stepping back.
Dialogue: 0,0:04:08.74,0:04:11.88,Default,,0000,0000,0000,,There is no attempt to create an ideal ecosystem,
Dialogue: 0,0:04:11.88,0:04:15.24,Default,,0000,0000,0000,,to produce a heath, a rainforest or a coral reef.
Dialogue: 0,0:04:15.24,0:04:17.79,Default,,0000,0000,0000,,Rewilding is about bringing back the species
Dialogue: 0,0:04:17.79,0:04:19.97,Default,,0000,0000,0000,,that drive dynamic processes
Dialogue: 0,0:04:19.97,0:04:22.34,Default,,0000,0000,0000,,and then letting nature take its course.
Dialogue: 0,0:04:22.34,0:04:25.13,Default,,0000,0000,0000,,But it's essential that rewilding must never be used
Dialogue: 0,0:04:25.13,0:04:27.97,Default,,0000,0000,0000,,as an excuse to push people off the land.
Dialogue: 0,0:04:27.97,0:04:29.72,Default,,0000,0000,0000,,It should happen only with the consent
Dialogue: 0,0:04:29.72,0:04:32.55,Default,,0000,0000,0000,,and enthusiasm of the people who work there.
Dialogue: 0,0:04:32.55,0:04:35.02,Default,,0000,0000,0000,,Imagine standing on a cliff in England,
Dialogue: 0,0:04:35.02,0:04:38.05,Default,,0000,0000,0000,,watching sperm whales attacking shoals of herring
Dialogue: 0,0:04:38.05,0:04:40.22,Default,,0000,0000,0000,,as they did within sight of the shore
Dialogue: 0,0:04:40.22,0:04:41.88,Default,,0000,0000,0000,,until the 18th century.
Dialogue: 0,0:04:41.88,0:04:43.55,Default,,0000,0000,0000,,By creating marine reserves
Dialogue: 0,0:04:43.55,0:04:45.38,Default,,0000,0000,0000,,in which no commerical fishing takes place,
Dialogue: 0,0:04:45.38,0:04:46.90,Default,,0000,0000,0000,,that can happen again.
Dialogue: 0,0:04:46.90,0:04:48.98,Default,,0000,0000,0000,,Imagine a European Serengeti
Dialogue: 0,0:04:48.98,0:04:51.32,Default,,0000,0000,0000,,full of the animals that used to live there:
Dialogue: 0,0:04:51.32,0:04:54.95,Default,,0000,0000,0000,,hippos, rhinos, elephants, hyenas and lions.
Dialogue: 0,0:04:54.95,0:04:57.13,Default,,0000,0000,0000,,What rewilding reintroduces,
Dialogue: 0,0:04:57.13,0:05:00.16,Default,,0000,0000,0000,,alongside the missing animals and plants,
Dialogue: 0,0:05:00.16,0:05:02.88,Default,,0000,0000,0000,,is that rare species called hope.
Dialogue: 0,0:05:02.88,0:05:05.00,Default,,0000,0000,0000,,It tells us that ecological change
Dialogue: 0,0:05:05.00,0:05:07.92,Default,,0000,0000,0000,,need not always proceed in the same direction.
Dialogue: 0,0:05:07.92,0:05:11.63,Default,,0000,0000,0000,,The silent spring could be followed by a wild summer.