[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:07.62,0:00:09.75,Default,,0000,0000,0000,,If someone called you scum,
Dialogue: 0,0:00:09.75,0:00:11.45,Default,,0000,0000,0000,,you'd probably be offended,
Dialogue: 0,0:00:11.45,0:00:12.87,Default,,0000,0000,0000,,but scientifically,
Dialogue: 0,0:00:12.87,0:00:14.45,Default,,0000,0000,0000,,they might not be far off.
Dialogue: 0,0:00:14.45,0:00:15.50,Default,,0000,0000,0000,,Have you ever thought about
Dialogue: 0,0:00:15.50,0:00:17.37,Default,,0000,0000,0000,,where your food comes from?
Dialogue: 0,0:00:17.37,0:00:18.72,Default,,0000,0000,0000,,You might say it comes from
Dialogue: 0,0:00:18.72,0:00:20.40,Default,,0000,0000,0000,,plants, animals, or even fungi,
Dialogue: 0,0:00:20.40,0:00:21.96,Default,,0000,0000,0000,,but you'd probably rather not
Dialogue: 0,0:00:21.96,0:00:23.72,Default,,0000,0000,0000,,think about the rotting organisms and poop
Dialogue: 0,0:00:23.72,0:00:26.87,Default,,0000,0000,0000,,that feed those plants, animals, and fungi.
Dialogue: 0,0:00:26.87,0:00:29.35,Default,,0000,0000,0000,,So really, you and most of the matter in your body
Dialogue: 0,0:00:29.35,0:00:31.94,Default,,0000,0000,0000,,are just two or three degrees of separation
Dialogue: 0,0:00:31.94,0:00:34.77,Default,,0000,0000,0000,,from things like pond scum.
Dialogue: 0,0:00:34.77,0:00:36.56,Default,,0000,0000,0000,,All species in an ecosystem,
Dialogue: 0,0:00:36.56,0:00:38.11,Default,,0000,0000,0000,,from the creatures in a coral reef
Dialogue: 0,0:00:38.11,0:00:39.48,Default,,0000,0000,0000,,to the fish in a lake
Dialogue: 0,0:00:39.48,0:00:40.82,Default,,0000,0000,0000,,to the lions on the savannah,
Dialogue: 0,0:00:40.82,0:00:42.36,Default,,0000,0000,0000,,are directly or indirectly
Dialogue: 0,0:00:42.36,0:00:44.32,Default,,0000,0000,0000,,nourished by dead stuff.
Dialogue: 0,0:00:44.32,0:00:46.83,Default,,0000,0000,0000,,Most of the organic matter in our bodies,
Dialogue: 0,0:00:46.83,0:00:48.62,Default,,0000,0000,0000,,if we trace it back far enough,
Dialogue: 0,0:00:48.62,0:00:50.41,Default,,0000,0000,0000,,comes from CO2 and water
Dialogue: 0,0:00:50.41,0:00:52.25,Default,,0000,0000,0000,,through photosynthesis.
Dialogue: 0,0:00:52.25,0:00:54.07,Default,,0000,0000,0000,,Plants use the energy from sunlight
Dialogue: 0,0:00:54.07,0:00:57.18,Default,,0000,0000,0000,,to transform carbon dioxide and water from the environment
Dialogue: 0,0:00:57.18,0:00:59.59,Default,,0000,0000,0000,,into glucose and oxygen.
Dialogue: 0,0:00:59.59,0:01:01.28,Default,,0000,0000,0000,,That glucose is then transformed
Dialogue: 0,0:01:01.28,0:01:02.70,Default,,0000,0000,0000,,into more complex organic molecules
Dialogue: 0,0:01:02.70,0:01:06.84,Default,,0000,0000,0000,,to form leaves, stems, roots, fruit, and so on.
Dialogue: 0,0:01:06.84,0:01:08.76,Default,,0000,0000,0000,,The energy stored in these organic molecules
Dialogue: 0,0:01:08.76,0:01:11.56,Default,,0000,0000,0000,,supports the food chains with which we're familiar.
Dialogue: 0,0:01:11.56,0:01:13.95,Default,,0000,0000,0000,,You've probably seen illustrations like this
Dialogue: 0,0:01:13.95,0:01:15.54,Default,,0000,0000,0000,,or this.
Dialogue: 0,0:01:15.54,0:01:16.98,Default,,0000,0000,0000,,These green food chains
Dialogue: 0,0:01:16.98,0:01:19.24,Default,,0000,0000,0000,,start with living plants at their base.
Dialogue: 0,0:01:19.24,0:01:22.03,Default,,0000,0000,0000,,But in real-life terrestrial ecosystems,
Dialogue: 0,0:01:22.03,0:01:23.99,Default,,0000,0000,0000,,less than 10% of plant matter
Dialogue: 0,0:01:23.99,0:01:26.00,Default,,0000,0000,0000,,is eaten while it's still alive.
Dialogue: 0,0:01:26.00,0:01:27.70,Default,,0000,0000,0000,,What about the other 90?
Dialogue: 0,0:01:27.70,0:01:29.16,Default,,0000,0000,0000,,Well, just look at the ground
Dialogue: 0,0:01:29.16,0:01:30.33,Default,,0000,0000,0000,,on an autumn day.
Dialogue: 0,0:01:30.33,0:01:32.08,Default,,0000,0000,0000,,Living plants shed dead body parts:
Dialogue: 0,0:01:32.08,0:01:33.75,Default,,0000,0000,0000,,fallen leaves, broken branches,
Dialogue: 0,0:01:33.75,0:01:35.50,Default,,0000,0000,0000,,and even underground roots.
Dialogue: 0,0:01:35.50,0:01:36.92,Default,,0000,0000,0000,,Many plants are lucky enough
Dialogue: 0,0:01:36.92,0:01:38.62,Default,,0000,0000,0000,,to go their whole lives without being eaten,
Dialogue: 0,0:01:38.62,0:01:41.25,Default,,0000,0000,0000,,eventually dying and leaving remains.
Dialogue: 0,0:01:41.25,0:01:44.54,Default,,0000,0000,0000,,All of these uneaten, undigested, and dead plant parts,
Dialogue: 0,0:01:44.54,0:01:47.20,Default,,0000,0000,0000,,that 90% of terrestrial plant matter?
Dialogue: 0,0:01:47.20,0:01:48.85,Default,,0000,0000,0000,,That becomes detritus,
Dialogue: 0,0:01:48.85,0:01:51.70,Default,,0000,0000,0000,,the base of what we call the brown food chain,
Dialogue: 0,0:01:51.70,0:01:54.03,Default,,0000,0000,0000,,which looks more like this.
Dialogue: 0,0:01:54.03,0:01:55.48,Default,,0000,0000,0000,,What happens to plants
Dialogue: 0,0:01:55.48,0:01:58.06,Default,,0000,0000,0000,,also happens to all other organisms up the food chain:
Dialogue: 0,0:01:58.06,0:01:59.40,Default,,0000,0000,0000,,some are eaten alive,
Dialogue: 0,0:01:59.40,0:02:00.82,Default,,0000,0000,0000,,but most are eaten only
Dialogue: 0,0:02:00.82,0:02:02.61,Default,,0000,0000,0000,,when they're dead and rotting.
Dialogue: 0,0:02:02.61,0:02:04.14,Default,,0000,0000,0000,,And all along this food chain,
Dialogue: 0,0:02:04.14,0:02:06.03,Default,,0000,0000,0000,,living things shed organic matter
Dialogue: 0,0:02:06.03,0:02:07.66,Default,,0000,0000,0000,,and expel digestive waste
Dialogue: 0,0:02:07.66,0:02:10.70,Default,,0000,0000,0000,,before dying and leaving their remains to decay.
Dialogue: 0,0:02:10.70,0:02:13.25,Default,,0000,0000,0000,,All that death sounds grim, right?
Dialogue: 0,0:02:13.25,0:02:14.58,Default,,0000,0000,0000,,But it's not.
Dialogue: 0,0:02:14.58,0:02:16.58,Default,,0000,0000,0000,,All detritus is ultimately consumed
Dialogue: 0,0:02:16.58,0:02:18.53,Default,,0000,0000,0000,,by microbes and other scavengers,
Dialogue: 0,0:02:18.53,0:02:21.17,Default,,0000,0000,0000,,so it actually forms the base of the brown food chain
Dialogue: 0,0:02:21.17,0:02:23.45,Default,,0000,0000,0000,,that supports many other organisms,
Dialogue: 0,0:02:23.45,0:02:25.37,Default,,0000,0000,0000,,including us.
Dialogue: 0,0:02:25.37,0:02:26.70,Default,,0000,0000,0000,,Scientists are learning
Dialogue: 0,0:02:26.70,0:02:27.47,Default,,0000,0000,0000,,that this detritus
Dialogue: 0,0:02:27.47,0:02:29.71,Default,,0000,0000,0000,,is an unexpectedly huge energy source,
Dialogue: 0,0:02:29.71,0:02:31.88,Default,,0000,0000,0000,,fueling most natural ecosystems.
Dialogue: 0,0:02:31.88,0:02:34.18,Default,,0000,0000,0000,,But the interactions within an ecosystem
Dialogue: 0,0:02:34.18,0:02:36.48,Default,,0000,0000,0000,,are even more complex than that.
Dialogue: 0,0:02:36.48,0:02:38.12,Default,,0000,0000,0000,,What a food chain really represents
Dialogue: 0,0:02:38.12,0:02:40.65,Default,,0000,0000,0000,,is a single pathway of energy flow.
Dialogue: 0,0:02:40.65,0:02:42.69,Default,,0000,0000,0000,,And within any ecosystem,
Dialogue: 0,0:02:42.69,0:02:43.86,Default,,0000,0000,0000,,many of these flows
Dialogue: 0,0:02:43.86,0:02:44.99,Default,,0000,0000,0000,,are linked together
Dialogue: 0,0:02:44.99,0:02:46.36,Default,,0000,0000,0000,,to form a rich network of interactions,
Dialogue: 0,0:02:46.36,0:02:48.74,Default,,0000,0000,0000,,or food web,
Dialogue: 0,0:02:48.74,0:02:52.24,Default,,0000,0000,0000,,with dead matter supporting that network at every step.
Dialogue: 0,0:02:52.24,0:02:53.54,Default,,0000,0000,0000,,The resulting food web
Dialogue: 0,0:02:53.54,0:02:54.62,Default,,0000,0000,0000,,is so connected
Dialogue: 0,0:02:54.62,0:02:55.83,Default,,0000,0000,0000,,that almost every species
Dialogue: 0,0:02:55.83,0:02:58.03,Default,,0000,0000,0000,,is no more than two degrees from detritus,
Dialogue: 0,0:02:58.03,0:03:00.00,Default,,0000,0000,0000,,even us humans.
Dialogue: 0,0:03:00.00,0:03:01.62,Default,,0000,0000,0000,,You probably don't eat rotting things,
Dialogue: 0,0:03:01.62,0:03:03.78,Default,,0000,0000,0000,,poop, or pond scum directly,
Dialogue: 0,0:03:03.78,0:03:06.09,Default,,0000,0000,0000,,but your food sources probably do.
Dialogue: 0,0:03:06.09,0:03:07.84,Default,,0000,0000,0000,,Many animals we eat
Dialogue: 0,0:03:07.84,0:03:09.93,Default,,0000,0000,0000,,either feed directly on detritus themselves,
Dialogue: 0,0:03:09.93,0:03:11.85,Default,,0000,0000,0000,,like pork, poultry, mushrooms, shellfish,
Dialogue: 0,0:03:11.85,0:03:15.48,Default,,0000,0000,0000,,or catfish and other bottom feeders,
Dialogue: 0,0:03:15.48,0:03:16.89,Default,,0000,0000,0000,,or they are fed animal by-products.
Dialogue: 0,0:03:16.89,0:03:19.69,Default,,0000,0000,0000,,So, if you're thinking nature is full of waste,
Dialogue: 0,0:03:19.69,0:03:20.94,Default,,0000,0000,0000,,you're right.
Dialogue: 0,0:03:20.94,0:03:23.57,Default,,0000,0000,0000,,But one organism's garbage is another's gold,
Dialogue: 0,0:03:23.57,0:03:25.02,Default,,0000,0000,0000,,and all that rotting dead stuff
Dialogue: 0,0:03:25.02,0:03:27.15,Default,,0000,0000,0000,,ultimately provides the energy that nourishes us
Dialogue: 0,0:03:27.15,0:03:29.07,Default,,0000,0000,0000,,and most of life on Earth,
Dialogue: 0,0:03:29.07,0:03:30.99,Default,,0000,0000,0000,,as it passes through the food web.
Dialogue: 0,0:03:30.99,0:03:35.18,Default,,0000,0000,0000,,Now that's some food for thought.