[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:07.66,0:00:09.38,Default,,0000,0000,0000,,They're long and slithery,
Dialogue: 0,0:00:09.38,0:00:11.04,Default,,0000,0000,0000,,and they're not very colorful.
Dialogue: 0,0:00:11.04,0:00:14.25,Default,,0000,0000,0000,,But they do have a strange beauty of their own.
Dialogue: 0,0:00:14.25,0:00:16.00,Default,,0000,0000,0000,,Their sinuous, nocturnal movements
Dialogue: 0,0:00:16.00,0:00:16.96,Default,,0000,0000,0000,,through the water
Dialogue: 0,0:00:16.96,0:00:18.88,Default,,0000,0000,0000,,are mesmerizing to watch.
Dialogue: 0,0:00:18.88,0:00:21.18,Default,,0000,0000,0000,,And though they may resemble underwater snakes,
Dialogue: 0,0:00:21.18,0:00:25.29,Default,,0000,0000,0000,,eels are, in fact, a very interesting type of fish.
Dialogue: 0,0:00:25.29,0:00:26.76,Default,,0000,0000,0000,,There are several things about eels
Dialogue: 0,0:00:26.76,0:00:28.13,Default,,0000,0000,0000,,that make them unique
Dialogue: 0,0:00:28.13,0:00:31.29,Default,,0000,0000,0000,,besides their elongated shape and limbless bodies.
Dialogue: 0,0:00:31.29,0:00:32.21,Default,,0000,0000,0000,,For one thing,
Dialogue: 0,0:00:32.21,0:00:35.73,Default,,0000,0000,0000,,eels have the ability to breathe through their skin.
Dialogue: 0,0:00:35.73,0:00:37.36,Default,,0000,0000,0000,,Some can even leave the water
Dialogue: 0,0:00:37.36,0:00:40.07,Default,,0000,0000,0000,,and move over land for short periods.
Dialogue: 0,0:00:40.07,0:00:42.04,Default,,0000,0000,0000,,And, unlike most migratory fish,
Dialogue: 0,0:00:42.04,0:00:43.13,Default,,0000,0000,0000,,such as salmon,
Dialogue: 0,0:00:43.13,0:00:44.57,Default,,0000,0000,0000,,which spawn in fresh water
Dialogue: 0,0:00:44.57,0:00:46.66,Default,,0000,0000,0000,,but live their adult lives in salt water,
Dialogue: 0,0:00:46.66,0:00:48.79,Default,,0000,0000,0000,,eels of the genus Anguilla
Dialogue: 0,0:00:48.79,0:00:50.75,Default,,0000,0000,0000,,migrate in the opposite direction,
Dialogue: 0,0:00:50.75,0:00:53.26,Default,,0000,0000,0000,,spawning and breeding in oceans and seas,
Dialogue: 0,0:00:53.26,0:00:55.13,Default,,0000,0000,0000,,while spending most of their intervening time
Dialogue: 0,0:00:55.13,0:00:56.96,Default,,0000,0000,0000,,in fresh water.
Dialogue: 0,0:00:56.96,0:00:59.17,Default,,0000,0000,0000,,If we were to take one such fresh water eel
Dialogue: 0,0:00:59.17,0:01:00.96,Default,,0000,0000,0000,,and follow its life story,
Dialogue: 0,0:01:00.96,0:01:03.76,Default,,0000,0000,0000,,it would be born in the middle of the North Atlantic Ocean,
Dialogue: 0,0:01:03.76,0:01:06.46,Default,,0000,0000,0000,,about a thousand miles east of Bermuda.
Dialogue: 0,0:01:06.46,0:01:08.80,Default,,0000,0000,0000,,This area, called the Sargasso Sea,
Dialogue: 0,0:01:08.80,0:01:10.35,Default,,0000,0000,0000,,forms the western part
Dialogue: 0,0:01:10.35,0:01:12.04,Default,,0000,0000,0000,,of a subtropical gyre,
Dialogue: 0,0:01:12.04,0:01:15.20,Default,,0000,0000,0000,,a giant whirlpool in the middle of the ocean.
Dialogue: 0,0:01:15.20,0:01:17.56,Default,,0000,0000,0000,,Our eel, let's call it Eli,
Dialogue: 0,0:01:17.56,0:01:21.24,Default,,0000,0000,0000,,would begin as one of ten to twenty million tiny eggs,
Dialogue: 0,0:01:21.24,0:01:23.24,Default,,0000,0000,0000,,carried by a female eel,
Dialogue: 0,0:01:23.24,0:01:25.71,Default,,0000,0000,0000,,hatching into a transparent leaf-shaped thing
Dialogue: 0,0:01:25.71,0:01:29.21,Default,,0000,0000,0000,,that looks nothing like an adult eel.
Dialogue: 0,0:01:29.21,0:01:31.29,Default,,0000,0000,0000,,Eli starts to drift in ocean currents,
Dialogue: 0,0:01:31.29,0:01:33.25,Default,,0000,0000,0000,,predominantly the Gulf Stream
Dialogue: 0,0:01:33.25,0:01:35.26,Default,,0000,0000,0000,,towards either Europe or North America,
Dialogue: 0,0:01:35.26,0:01:38.46,Default,,0000,0000,0000,,depending on its particular species.
Dialogue: 0,0:01:38.46,0:01:40.04,Default,,0000,0000,0000,,Upon reaching the coast,
Dialogue: 0,0:01:40.04,0:01:41.88,Default,,0000,0000,0000,,Eli is about two inches long,
Dialogue: 0,0:01:41.88,0:01:44.51,Default,,0000,0000,0000,,looking more eely but still transparent,
Dialogue: 0,0:01:44.51,0:01:47.26,Default,,0000,0000,0000,,known at this stage as a glass eel.
Dialogue: 0,0:01:47.26,0:01:49.04,Default,,0000,0000,0000,,But within a couple of days in fresh water,
Dialogue: 0,0:01:49.04,0:01:52.10,Default,,0000,0000,0000,,Eli's skin becomes pigmented a brownish-black,
Dialogue: 0,0:01:52.10,0:01:55.35,Default,,0000,0000,0000,,now looking more like that of an adult eel.
Dialogue: 0,0:01:55.35,0:01:56.40,Default,,0000,0000,0000,,You might notice
Dialogue: 0,0:01:56.40,0:01:57.65,Default,,0000,0000,0000,,that we haven't mentioned anything
Dialogue: 0,0:01:57.65,0:01:59.46,Default,,0000,0000,0000,,about Eli's gender yet.
Dialogue: 0,0:01:59.46,0:02:01.29,Default,,0000,0000,0000,,That's because this is only determined
Dialogue: 0,0:02:01.29,0:02:03.11,Default,,0000,0000,0000,,once an eel enters fresh water,
Dialogue: 0,0:02:03.11,0:02:06.32,Default,,0000,0000,0000,,though nobody is sure exactly how that happens.
Dialogue: 0,0:02:06.32,0:02:08.91,Default,,0000,0000,0000,,Most of the eels that stay in the estuaries
Dialogue: 0,0:02:08.91,0:02:10.83,Default,,0000,0000,0000,,and brackish water become males,
Dialogue: 0,0:02:10.83,0:02:13.16,Default,,0000,0000,0000,,while those that go upstream become females,
Dialogue: 0,0:02:13.16,0:02:15.21,Default,,0000,0000,0000,,growing up to two to three times bigger than
Dialogue: 0,0:02:15.21,0:02:17.46,Default,,0000,0000,0000,,their future mates.
Dialogue: 0,0:02:17.46,0:02:18.42,Default,,0000,0000,0000,,In this case,
Dialogue: 0,0:02:18.42,0:02:22.34,Default,,0000,0000,0000,,it turns out that Eli was actually short for Elaine.
Dialogue: 0,0:02:22.34,0:02:23.42,Default,,0000,0000,0000,,As a female eel,
Dialogue: 0,0:02:23.42,0:02:25.01,Default,,0000,0000,0000,,Elaine will be quite solitary
Dialogue: 0,0:02:25.01,0:02:26.79,Default,,0000,0000,0000,,for most of her life in the stream,
Dialogue: 0,0:02:26.79,0:02:28.84,Default,,0000,0000,0000,,eating whatever falls in the water:
Dialogue: 0,0:02:28.84,0:02:31.35,Default,,0000,0000,0000,,grasshoppers, crickets, small fish,
Dialogue: 0,0:02:31.35,0:02:34.24,Default,,0000,0000,0000,,insect larvae, frogs, baby birds,
Dialogue: 0,0:02:34.24,0:02:37.13,Default,,0000,0000,0000,,almost anything she can get her mouth around.
Dialogue: 0,0:02:37.13,0:02:38.69,Default,,0000,0000,0000,,And she will grow quite big,
Dialogue: 0,0:02:38.69,0:02:40.23,Default,,0000,0000,0000,,up to four feet long
Dialogue: 0,0:02:40.23,0:02:43.38,Default,,0000,0000,0000,,and weighing as much as thirteen pounds.
Dialogue: 0,0:02:43.38,0:02:44.88,Default,,0000,0000,0000,,We don't know exactly how
Dialogue: 0,0:02:44.88,0:02:46.28,Default,,0000,0000,0000,,fresh water eels know when it's time
Dialogue: 0,0:02:46.28,0:02:47.91,Default,,0000,0000,0000,,to return to the ocean,
Dialogue: 0,0:02:47.91,0:02:49.62,Default,,0000,0000,0000,,but something calls to them.
Dialogue: 0,0:02:49.62,0:02:50.91,Default,,0000,0000,0000,,And their fall migration
Dialogue: 0,0:02:50.91,0:02:52.74,Default,,0000,0000,0000,,is one of the largest unseen migrations
Dialogue: 0,0:02:52.74,0:02:54.58,Default,,0000,0000,0000,,on the planet.
Dialogue: 0,0:02:54.58,0:02:56.50,Default,,0000,0000,0000,,As Elaine leaves fresh water for the ocean,
Dialogue: 0,0:02:56.50,0:02:59.63,Default,,0000,0000,0000,,she undergoes a shocking metamorphosis.
Dialogue: 0,0:02:59.63,0:03:02.13,Default,,0000,0000,0000,,Her eyes enlarge by about ten times,
Dialogue: 0,0:03:02.13,0:03:03.71,Default,,0000,0000,0000,,her skin gets thicker,
Dialogue: 0,0:03:03.71,0:03:06.04,Default,,0000,0000,0000,,and her fins get larger.
Dialogue: 0,0:03:06.04,0:03:07.76,Default,,0000,0000,0000,,These are most likely adaptations
Dialogue: 0,0:03:07.76,0:03:09.59,Default,,0000,0000,0000,,for their upcoming ocean travel,
Dialogue: 0,0:03:09.59,0:03:11.68,Default,,0000,0000,0000,,and Elaine seamlessly makes the transition
Dialogue: 0,0:03:11.68,0:03:13.63,Default,,0000,0000,0000,,from fresh to salt water,
Dialogue: 0,0:03:13.63,0:03:16.71,Default,,0000,0000,0000,,which would be toxic for most other fish.
Dialogue: 0,0:03:16.71,0:03:18.94,Default,,0000,0000,0000,,Once Elaine leaves the mouth of the fresh water streams,
Dialogue: 0,0:03:18.94,0:03:22.19,Default,,0000,0000,0000,,she will disappear completely from human view.
Dialogue: 0,0:03:22.19,0:03:23.73,Default,,0000,0000,0000,,No one has witnessed,
Dialogue: 0,0:03:23.73,0:03:25.15,Default,,0000,0000,0000,,or been able to follow,
Dialogue: 0,0:03:25.15,0:03:27.11,Default,,0000,0000,0000,,an adult eel on their migration,
Dialogue: 0,0:03:27.11,0:03:29.90,Default,,0000,0000,0000,,nor do we know how deep they spawn.
Dialogue: 0,0:03:29.90,0:03:32.66,Default,,0000,0000,0000,,But it's assumed that they can follow some signs
Dialogue: 0,0:03:32.66,0:03:34.16,Default,,0000,0000,0000,,that they can detect,
Dialogue: 0,0:03:34.16,0:03:36.45,Default,,0000,0000,0000,,such as a thermal barrier between ocean currents
Dialogue: 0,0:03:36.45,0:03:37.95,Default,,0000,0000,0000,,or a salinity front,
Dialogue: 0,0:03:37.95,0:03:40.31,Default,,0000,0000,0000,,in order to return to the same area of the ocean
Dialogue: 0,0:03:40.31,0:03:42.18,Default,,0000,0000,0000,,where they were born.
Dialogue: 0,0:03:42.18,0:03:44.08,Default,,0000,0000,0000,,Because we don't even know exactly
Dialogue: 0,0:03:44.08,0:03:46.01,Default,,0000,0000,0000,,what happens during an eel's migration,
Dialogue: 0,0:03:46.01,0:03:49.13,Default,,0000,0000,0000,,we can only imagine what the actual breeding looks like.
Dialogue: 0,0:03:49.13,0:03:50.71,Default,,0000,0000,0000,,But the common hypothesis
Dialogue: 0,0:03:50.71,0:03:52.46,Default,,0000,0000,0000,,is that Elaine and thousands,
Dialogue: 0,0:03:52.46,0:03:53.76,Default,,0000,0000,0000,,or hundreds of thousands,
Dialogue: 0,0:03:53.76,0:03:54.71,Default,,0000,0000,0000,,of other eels
Dialogue: 0,0:03:54.71,0:03:57.13,Default,,0000,0000,0000,,gather in large, intertwined masses
Dialogue: 0,0:03:57.13,0:03:58.79,Default,,0000,0000,0000,,and release their eggs and sperm
Dialogue: 0,0:03:58.79,0:04:01.90,Default,,0000,0000,0000,,in a giant orgy known as panmixia.
Dialogue: 0,0:04:01.90,0:04:03.90,Default,,0000,0000,0000,,A couple of days after the eggs are laid,
Dialogue: 0,0:04:03.90,0:04:04.81,Default,,0000,0000,0000,,they hatch,
Dialogue: 0,0:04:04.81,0:04:06.61,Default,,0000,0000,0000,,and the cycle begins again.
Dialogue: 0,0:04:06.61,0:04:08.04,Default,,0000,0000,0000,,And because we've never seen
Dialogue: 0,0:04:08.04,0:04:10.66,Default,,0000,0000,0000,,the adult eels returning up the fresh water rivers,
Dialogue: 0,0:04:10.66,0:04:11.88,Default,,0000,0000,0000,,we must assume that,
Dialogue: 0,0:04:11.88,0:04:14.41,Default,,0000,0000,0000,,having completed their long and roundabout journey,
Dialogue: 0,0:04:14.41,0:04:16.70,Default,,0000,0000,0000,,these amazing and mysterious creatures
Dialogue: 0,0:04:16.70,0:04:18.30,Default,,0000,0000,0000,,finally die there,
Dialogue: 0,0:04:18.30,0:04:20.57,Default,,0000,0000,0000,,in the same place where they were born.
Dialogue: 0,0:04:20.57,0:04:22.00,Default,,0000,0000,0000,,Goodbye, Elaine!
Dialogue: 0,0:04:22.00,0:04:23.71,Default,,0000,0000,0000,,It was a pleasure knowing you.