Chapter Content
Okay, so like, imagine, could you actually *live* in a world, like, completely ruled by dihydrogen monoxide? I mean, it sounds kind of sci-fi, right? But get this, it's just, you know, water.
It's this totally colorless, odorless compound, super versatile, usually pretty chill, but, uh, sometimes it can be, like, totally deadly. It can burn you, it can freeze you, depending on what state it's in, obviously. And if there are, like, certain organic molecules around, it can form carbonic acid. Which, ugh, carbonic acid is the worst! It makes leaves fall off trees, eats away at statues. And in huge quantities, if it gets, like, riled up, it'll just wreck everything. No human building stands a chance. And even for those of us who've, like, learned to live with it, it’s still kinda dangerous, you know? Like, every year, thousands of people drown.
Seriously, water is *everywhere*. A potato is, like, 80% water. A cow, 74%. Even bacteria is 75% water. A tomato? Ninety-five percent! Basically just water with a little tomato flavor, haha. And humans? We’re, like, 65% water. That means the liquid-to-solid ratio in our bodies is almost two-to-one. Isn't that wild?
And it's just such a weird thing. It's shapeless, see-through, but, like, we love being near it. It has no taste, but we still like to, you know, taste it. We travel for miles, spend tons of money, just to look at it sparkle in the sun. Even though we *know* it’s dangerous, we can't wait to jump in, right?
Because it's *so* common, we tend to forget it's actually a pretty freakin' extraordinary substance. Almost nothing about it allows you to predict how any other liquid will behave, and vice versa. Like, if you knew nothing about water, but you looked at other, chemically similar compounds, like, especially hydrogen selenide or hydrogen sulfide, you'd expect water to boil at, like, -93 degrees Celsius and be a gas at room temperature. Crazy, right?
Most liquids shrink when they get colder, right? Usually about 10%. Water does too, but, like, only to a point. As it approaches freezing, it starts to—and this is so weird—it starts to expand! Like, against all logic. And when it turns solid, it's, like, almost 10% bigger than it was before. Because water expands when it freezes, ice floats! That’s actually a pretty amazing property.
I mean, think about it. If ice sank, lakes and oceans would freeze from the *bottom* up. And without that layer of surface ice to insulate the water below, the heat would just escape, the water would get colder, and more ice would form. Pretty soon, the whole lake or ocean would be frozen solid, and, like, probably stay that way forever. Conditions like that, they're not exactly conducive to life. So, thank goodness, water seems to, you know, ignore the laws of chemistry and physics.
Okay, so, you know the chemical formula for water is H2O. That means it’s made up of one bigger oxygen atom and two smaller hydrogen atoms stuck to it. The hydrogen atoms are really clinging to that oxygen, but their connection to other water molecules is, like, pretty casual. So, it's like they're always dancing with each other. Pairing up for a little bit, then moving on. Like a square dance, constantly changing partners, you know? A glass of water might seem lifeless, but every molecule is switching partners billions of times per second. That’s why water molecules can stick together enough to form puddles and lakes, but not so tightly that they can't be separated, like when you jump into a pond. At any given moment, only about 15% of water molecules are actually touching each other.
In some ways, though, this bonding is super strong. That's why water can travel up a straw. It's also why little droplets on a car hood will kind of merge into larger beads. It gives water surface tension. The molecules on the surface are pulled more strongly to the molecules beneath and beside them than they are to the air above. This creates a kind of skin, strong enough for insects to walk on, or for you to skip a stone. It even provides a little support for diving, right?
I mean, it almost goes without saying that we couldn't exist without water. Without water, our bodies would, like, quickly fall apart. Like, lips disappearing, "as if sliced off," gums turning black, noses shrinking, skin around the eyes tightening so you can’t blink… It's pretty brutal.
But, here's the thing, most of the water on Earth is actually toxic to us. And it's toxic *because* it's salty.
We need salt to live, but only in tiny amounts. Seawater is way too salty, like, 70 times too salty for us to safely process. There's about 2.5 teaspoons of regular salt in a liter of seawater. It’s the kind we sprinkle on our food, sure, but it also contains a huge assortment of other elements, compounds, and dissolved solids, all lumped together as “salt.” And the ratio of salts and minerals in our tissues is pretty similar to the ratio in seawater.
We sweat seawater, we cry seawater. But, weirdly, we can't handle ingesting it. If you introduce a lot of salt into your system, your metabolism goes haywire real fast. The water molecules in every cell rush out, like volunteer firefighters, trying to dilute and flush away the sudden salt influx. As a result, the cells get severely dehydrated and can't function properly. Basically, they shrivel up. In extreme cases, this can lead to seizures, coma, and brain damage. Meanwhile, overworked blood cells ferry the salt to the liver, and eventually the kidneys get overloaded and shut down. If the kidneys fail, you die. That’s why you can’t drink seawater.
There are, like, 1.3 billion cubic kilometers of water on Earth, and that's it. It’s a closed system. It’s never going to increase or decrease. The water you’re drinking? It's been around since the planet formed, like, three point eight billion years ago. The oceans were basically the size they are now, three point eight billion years ago. Whoa.
This, like, body of water is called the hydrosphere, and most of it is ocean. Like, 97% of Earth's water is in the ocean, and the Pacific Ocean is the big kahuna. It’s larger than all the landmasses combined. Overall, the Pacific contains over half, like, 51.6%, of all seawater. The Atlantic has 23.6%. The Indian Ocean has 21.2%. And all the other oceans combined only make up about 3.6%. The average depth of the ocean is almost four kilometers, and the Pacific is, like, 300 meters deeper than the Atlantic and Indian Oceans. Sixty percent of the planet’s surface is ocean deeper than 1.6 kilometers. Someone even said that this planet should be called Ocean, not Earth. I mean, makes sense, right?
Only 3% of the water on Earth is fresh water. Most of that is in icecaps. And only a tiny bit, like, 0.036%, of freshwater is in lakes, rivers, and reservoirs. Even smaller, 0.001%, is in clouds or in the atmosphere as vapor. Almost 90% of Earth’s ice is in Antarctica. The rest is mostly in Greenland.
If you go to Antarctica, you're standing on, like, three kilometers of ice! In the Arctic, it's only four or five meters thick. Antarctica alone contains 25 million cubic kilometers of ice. If it all melted, it would raise sea levels by, like, sixty meters. On the other hand, if every drop of water in the atmosphere fell as rain, evenly across the globe, the oceans would only deepen by, like, two centimeters.
Oh, and by the way, sea level is basically just a theoretical concept. The sea isn't flat. Tides, wind, the Coriolis effect, and other stuff, they all cause huge variations in ocean levels, even within the same ocean. The western edge of the Pacific is about 45 centimeters higher, because of centrifugal forces from Earth’s rotation. It's like when you pull a bowl of water, the water wants to stay behind. It’s the same deal. The Earth’s rotation, west to east, pushes the water toward the western edge of the ocean.
The ocean has always been super important to us, right? So it's kind of surprising that science took so long to get interested in it. Up until the 1800s, our understanding of the ocean mostly came from stuff that washed up on the beach or got caught in fishing nets. Almost everything written about it was based on, like, anecdotes and speculation, not actual evidence. One naturalist surveyed seabeds in the Atlantic and Mediterranean and declared that there was no life deeper than 600 meters. That seemed logical. No light, no plants, and, supposedly, extreme pressure at that depth. So, people were kind of shocked when they pulled up a trans-Atlantic cable for repairs, from, like, three kilometers down, and found it covered in coral, clams, and other small creatures.
The first real organized survey of the ocean didn’t happen until, like, 1872. The British Museum, the Royal Society, and the British government got together and sent out the HMS Challenger. Over three and a half years, they sailed around the world, collecting water samples, catching fish, dredging up sediment. It sounds pretty monotonous, to be honest. A quarter of the scientists and crew deserted. Eight either died or went insane. According to a historian, "years of monotony dulled minds and drove men mad." But, they traveled almost 70,000 nautical miles, collected over 4,700 new species, gathered enough information to write a 50-volume report, and, like, basically created a new science: oceanography. They also discovered what appeared to be a mountain range underwater in the middle of the Atlantic. Some of them got really excited and thought they’d found Atlantis.
Because academic institutions weren’t that interested in the ocean, a small number of enthusiastic amateurs told us a lot about what's down there. Modern deep-sea exploration kind of started with two guys. They designed and funded the construction of the first bathysphere, which is Greek for "deep." It was just a small, sturdy diving bell made of thick cast iron, with two thick quartz windows. It could hold two people, but you’d have to be okay with being very, very close. Even by the standards of the time, the tech was pretty basic. The sphere was just, like, dangling from a long cable, with a really simple breathing system. To neutralize carbon dioxide, they opened cans of lime. To absorb moisture, they opened little trays of calcium chloride. And to speed things up, they sometimes waved palm fronds.
But that unnamed little bathysphere worked. In 1930, they dove to about 180 meters. By 1934, they'd pushed that to over 900 meters. It wasn't broken until after World War II. But it was a brave and dangerous job. At 900 meters, the little windows had about 3 tons of pressure per square centimeter pressing on them. If the structure gave way, death would be instantaneous. They worried that the cable, with its metal sphere and two tons of steel cable, would snap and send them to the bottom.
Their experiments didn’t result in huge scientific breakthroughs. They saw creatures they hadn't seen before, but visibility was limited, and neither of them was a trained marine biologist. There were no lights on the outside, and they could only look out through the thick quartz glass. So, they basically had to hope something equally interested in *them* would swim by. They reported seeing lots of weird stuff. One time, one of them saw, like, a 6-meter snake, "very thick." It swam past so fast it was just a blur. No one's ever seen anything like it since. The reports were so vague that the scientific community didn't really take notice.
After the record-breaking dive, one of them lost interest in diving and moved on, but the other guy kept going. When asked, he always gave credit to the guy who had actually organized the project. That guy wrote exciting stories about their underwater adventures and even played a role in a movie called "Titans of the Deep," describing the bathysphere and lots of encounters with fierce giant squid. Those stories were exciting, but pretty much fictional. He even advertised for Camel cigarettes, saying they helped his nerves! He dived to 1,370 meters, about a 50% increase on the depth record. A newspaper reviewing his movie even said the real star was the other guy! We’re lucky if we even remember his name now.
Anyway, he soon faded into the background when this father-son team from Switzerland came along. They designed a new kind of submersible called a bathyscape. It was built in Trieste, Italy, and was named the *Trieste*. It could move independently, although it could still only go up and down. On its first dive, it went to 4,000 meters, almost three times the record set years earlier. But deep-sea diving is really expensive, and they were running out of money.
They made a deal with the U.S. Navy, giving them ownership of the *Trieste*, but keeping the right to use it. That gave them some serious funds to upgrade the ship. They made the walls, like, 13 centimeters thick, and shrunk the windows down to, like, five centimeters in diameter. Basically just little peepholes. But the bathyscape was now really, really strong and could withstand immense pressure.
In 1960, the son and a naval officer slowly sank into the deepest canyon in the ocean, the Mariana Trench, near Guam. They spent under four hours descending almost eleven kilometers. At that depth, the pressure was about 1,200 kilograms per square centimeter, but they were surprised to see flatfish swimming around the bottom. They didn't have cameras, so there’s no record.
They only spent about 20 minutes at the deepest point in the world, then came back up. And humans have never been that deep since.
So, more than 40 years later, why hasn’t anyone gone back? First of all, there was strong opposition from a naval admiral. He was a stickler for details, and he controlled the Navy’s purse strings. He thought underwater exploration was a waste of money and pointed out that the Navy wasn't a research organization. Plus, the country was putting all its energy into space travel, trying to get to the moon. So, deep-sea exploration seemed unimportant, obsolete.
But the biggest factor was that the *Trieste* hadn't really accomplished that much. As one Navy official said a few years later, "We just knew we could do it, and didn't learn a hell of a lot else. Why bother?" It’s just a really long and expensive trip to find some fish. Someone estimated that it would cost at least 100 million dollars to do it again today.
When underwater researchers heard that the Navy wasn’t going to do what it said, they protested loudly. To calm things down, the Navy provided money to build a more advanced submersible, managed by the Woods Hole Oceanographic Institute in Massachusetts. It was named *Alvin*, after an oceanographer. It would be a nimble, tiny submarine, although it couldn’t go anywhere near as deep as the *Trieste*. There was only one problem: the designers couldn’t find anyone to build it. No major company wanted a project that the Navy and admiral didn’t care about. Incredibly, *Alvin* was built in a factory that made breakfast cereal machines.
As for what else is underwater, we really don't know much. Until the 1950s, the best charts oceanographers had were based on scattered surveys and a lot of guesswork. The U.S. Navy had good charts, to guide submarines through canyons, but it didn’t want to share the info with the Soviets, so it kept the information secret. Academics had to make do with simple, outdated maps or just guess. Even today, we know very little about the seabed. If you look at the moon through a telescope, you see tons of craters. If they were on our own seabed, we’d have no idea they were there. We have better maps of Mars than we do of our own seabed.
Even at sea level, exploration has been a bit haphazard. In 1994, a Korean ship in the Pacific ran into a storm and 34,000 hockey gloves got washed overboard. Gloves washed up everywhere, from Vancouver to Vietnam, letting oceanographers track ocean currents more accurately than ever.
Today, *Alvin* is almost forty years old, and it’s still one of the premier research vessels in the world. Right now, there are only five submersibles that can reach the “abyssal plains”—the deep sea floor that covers over half the planet. Because the operation of a regular submersible costs up to $25,000 a day, you're not just going to randomly sink into the sea and bump into something interesting. Our firsthand experience of the planet is like it's based on nocturnal tractor rides by five people. Humanity has probably only looked at "a millionth, or a billionth, or maybe less...maybe much less, of the dark ocean."
But oceanographers have been working hard, and they’ve made a few big discoveries with limited resources. One of the most important was in 1977. *Alvin* found big communities of big creatures living on and around deep-sea vents near the Galapagos Islands. Three-meter-long tube worms, 30-centimeter-wide clams, huge numbers of shrimp and mussels, wriggling tubeworms. They realized that the creatures existed because of communities of bacteria. The bacteria got their energy and nutrition from hydrogen sulfide, a compound extremely toxic to surface life, that spewed out of the vents. This world was independent of sunlight, oxygen, or anything else usually associated with life. Instead of photosynthesis, life was based on chemosynthesis. Biologists would’ve called it absurd if anyone had suggested this setup.
The vents release tons of heat and energy. Twenty or so vents produce as much energy as a large power plant. The temperature also varies a lot. The vents can get up to 400 degrees Celsius, while the water two meters away might be just a couple of degrees above freezing. They even found a worm that lived on the edge, with its head in water that was 78 degrees warmer than its tail! Previously, people thought that complex organisms couldn't survive in water above 54 degrees. This changed how we saw the needs of life.
It also answered a big question in oceanography, a question most people don’t even know is a question: why isn’t the ocean getting saltier? It’s pretty clear that there’s a lot of salt in the ocean, enough to cover every bit of land on the planet to a depth of, like, 150 meters. Rivers dump minerals into the ocean, and these minerals combine with seawater ions to form salt. Okay, no problem. But, it was weird that the salinity of seawater stays constant. Millions of gallons of fresh water evaporate, leaving all the salt behind, so logically the ocean should get saltier as time goes on. But it doesn’t. So something must be taking the salt away, in equal measure to what’s coming in. For a long time, no one could figure out what.
The discovery of deep-sea vents provided the answer. Geophysicists realized that they work like filters in a fish tank. Water flows into the earth's crust and is stripped of salt. Eventually, fresh water spews out of the vents. It’s not quick, it takes about 10 million years to clean an ocean, but if you’re not in a hurry, it’s really effective.
Psychologically, we’re really distant from the deep ocean. One of the main goals presented during an international geophysics meeting, made this point pretty clearly. They wanted to study “the use of ocean depths for the disposal of radioactive waste.” This wasn't a secret mission, it was proudly declared. Although it wasn't talked about as openly, radioactive waste dumping had been going on for over ten years. The U.S. had been shipping drums of radioactive waste to the Farallon Islands, and just shoving them into the sea.
Most of the drums were the kind you see rusting behind gas stations. They didn’t have any protective lining. If the drums didn’t sink, the Navy would riddle them with bullets and let the seawater in. Which, of course, also released plutonium, uranium, and strontium. By the time it stopped, the U.S. had dumped tens of thousands of barrels of this stuff in about 50 locations in the ocean. But the U.S. wasn’t the only country doing this. Russia, Japan, New Zealand, and pretty much all European countries were also enthusiastic dumpers.
What effect does all this have on the ocean? Well, hopefully very little. But we really don't know. We’re surprisingly ignorant about the creatures that live there. We often know very little about even the largest creatures, even the biggest, most gigantic blue whale. This behemoth is so big that its tongue weighs as much as an elephant, its heart is the size of a car, and some of its blood vessels are big enough to swim through. It’s the largest animal that’s ever lived on Earth, bigger than the biggest dinosaur. But, the blue whale’s life is mostly a mystery to us. We don’t know where they go for much of the year, or where they give birth. Almost everything we know about them comes from listening to their calls, which are also a mystery. Blue whales sometimes stop calling suddenly, and then start up again in the same spot six months later. Sometimes they make a new kind of call, one that maybe no blue whale has ever heard before, but every blue whale understands it. We have no idea how or why. And these animals have to come to the surface to breathe, constantly!
As for the animals that never have to surface, their mysteriousness is probably even more curious. Think about the giant squid. While it’s not as big as a blue whale, it’s still huge. It has eyes the size of soccer balls and tentacles that can reach 18 meters. It weighs almost a ton and is the biggest invertebrate on Earth. But no scientist, or anyone else that we know of, has ever seen a living giant squid. Some zoologists have spent their entire lives trying to catch or even just see one, and they’ve always failed. People only know they exist because they wash up on beaches, mostly on the South Island of New Zealand. They must be numerous, because they’re the main food source for sperm whales, and sperm whales eat a lot.
One estimate says that there could be as many as 30 million species living in the ocean, and most of them haven’t even been discovered yet. It wasn’t until the 1960s, when they invented the trawl, that we first realized that the deep sea was actually rich with life. It’s a digging device that can catch not just animals on the sea floor, but also animals buried in the sediment. At about a kilometer and a half deep, marine biologists trawled up 25,000 animals, representing 365 species, in an hour. Even as deep as almost five kilometers, they found about 3,700 animals, representing almost 200 species. But trawls only catch what’s too slow or too stupid to get out of the way. In the late 1960s, marine biologist tried putting baited cameras in the sea. They found many more animals, especially groups of hagfish, primitive eel-like creatures, and swarms of grenadiers. These animals travel from up to 1,600 kilometers away to feed on dead whales that have sunk to the bottom.
So, how is it that we're able to so easily overload the ocean? First, not all the ocean is very productive. In total, less than a tenth of the ocean is considered naturally fertile. Most aquatic animals prefer to be in shallow water, where there's warmth, light, and organic matter to nourish the food chain. Coral reefs, for example, take up far less than 1% of the ocean space, but they’re home to about 25% of all marine fish.
Elsewhere, the ocean just isn’t that abundant. Take Australia. It has the third-longest coastline in the world, and more ocean waves hitting its shores than any other country, but it doesn’t even rank in the top 50 fishing nations. Australia is actually a net importer of seafood, because much of its ocean, like much of Australia itself, is desert. One exception is the Great Barrier Reef, which is really fertile. Because the soil is poor, the runoff contains almost no nutrients.
Even the rich areas of the ocean are pretty sensitive to disturbance. In the 1970s, Australian and New Zealand fishermen found big populations of an obscure fish, the orange roughy, about 800 meters deep. It was delicious and plentiful, so fleets started hauling it in at a rate of 40,000 tons a year. Then, marine biologists made some startling discoveries. Orange roughies live really long and mature really slowly. Some live for 150 years. Any orange roughy on your plate was probably born when Queen Victoria was on the throne. Orange roughies live at such a slow pace because they live in nutrient-poor water, where fish only reproduce once in their lives. Clearly, they can’t handle a lot of interference. Unfortunately, by the time people realized this, the stocks had already been severely reduced. Even if managed well, it’ll take decades for them to recover, if they ever do.
But in other places, the misuse of the ocean is worse than careless. It’s wanton. Many fishermen "fin" sharks. They cut off the fins and then throw the sharks back in the water to die. In 1998, shark fins sold for over $110 per kilogram in the Far East. A bowl of shark fin soup retailed for $100 in Tokyo. The World Wildlife Fund estimated in 1994 that 40 to 70 million sharks are killed every year.
By 1995, there were about 37,000 industrial-scale fishing boats in the world, plus about a million smaller vessels. They were taking twice as much fish out of the ocean every year as they had 25 years earlier. Modern trawlers are sometimes bigger than cruise ships, dragging nets big enough to hold a dozen jumbo jets. Some even use reconnaissance aircraft to find schools of fish from the air.
For every net hauled in, about a quarter is considered "bycatch." That’s fish that are too small to keep, or fish that shouldn't be caught, or fish that shouldn't be caught that season. As one observer told the *Economist*, "We're still in the dark ages. We just throw the net down and see what comes up." Up to 22 million tons of this unwanted fish is dumped back into the sea every year, most of it dead. For every kilogram of shrimp harvested, about four kilograms of fish and other marine life are doomed.
Large areas of the North Sea seabed are swept seven times a year by bottom-dragging trawlers. No ecosystem can withstand that kind of disturbance. It’s estimated that at least two-thirds of the fish in the North Sea are overfished. Off the coast of New England, there used to be so many halibut that individual boats could haul in over 9,000 kilograms in a single day. Today, halibut are almost extinct off the northeastern coast of the U.S.
But the saddest story is probably the cod. In the late 1400s, explorer John Cabot found so many cod off the banks of eastern North America that it was unbelievable. The banks are shallow areas of water where bottom-feeding fish like cod love to go. There were so many cod that Cabot reported, with amazement, that sailors could just scoop them up with baskets. Some of the banks were huge. Georges Bank, off Massachusetts, is bigger than the state it sits next to. The Grand Banks, off Newfoundland, is even bigger. For centuries, they were covered with cod, and were considered an inexhaustible resource. Of course, that wasn’t the case.
It’s estimated that by 1960, the number of cod spawning in the North Atlantic had been reduced to 1.6 million tons. By 1990, that number had dropped to 22,000 tons. Cod were commercially extinct. "Fishermen," wrote Mark Kurlansky in his fascinating history *Cod*, "had simply taken all the cod." The western Atlantic may never see cod again. The Grand Banks were completely closed to cod fishing in 1992, but as of 2002, the stocks still showed no sign of recovery. Kurlansky points out that fish fillets used to mean cod, then they meant haddock, then they meant red snapper, and most recently they meant Pacific pollack. Now, he says dryly, "fish" means "whatever's left."
Much the same can be said for many other types of seafood. Lobster, for example. Around Rhode Island, it used to be common to catch big ones, over nine kilograms. Untouched, lobsters can live for decades. Up to 70 years, it’s thought. They keep getting bigger. Today, it’s rare to catch anything over a kilogram. A *New York Times* article said that biologists estimate that within a year of reaching the legal minimum size, at about six years old, 90% of lobsters are caught. Despite dwindling catches, state and federal governments are still encouraging fishermen to buy bigger boats and scour the sea more thoroughly.
We hardly know the forces that govern life in the ocean. On one hand, there are overfished waters, where there’s less life than there should be. On the other, there are naturally poor waters, where there’s more life than there should be. In the Southern Ocean around Antarctica, which only produces about 3% of the world’s phytoplankton, it's hard to see that there's enough to sustain a complex ecosystem. Yet, it does. Crabeater seals, which most of us haven’t even heard of, may be the second-most-numerous large animal on the planet, after humans. Up to 15 million crabeater seals live on the pack ice around Antarctica. There are also about 2 million Weddell seals, and at least half a million emperor penguins, and possibly as many as 4 million Adélie penguins. So, the food chain is severely imbalanced, but somehow it works. Remarkably, no one knows why.
So, the main point of this long rambling discussion is that we know relatively little about the largest thing on our planet. Yet, as we’ll see in the coming chapters, there’s also an awful lot that we don’t know when we start to talk about the problem of life, in particular, how it first came about.