Transcripts
In the beginning, it was quiet. There were currents
Amy Martin:and waves, downpours, fractures, eruptions, and eventually, the
Amy Martin:burble of oxygen being released by communities of microbes in
Amy Martin:the sea. But it took almost 4 billion years for the first
Amy Martin:complex life forms to emerge on Earth. They were soft bodied
Amy Martin:things, jellies, sponges, sea anemones and corals. None of
Amy Martin:them were big talkers. Last time we met earth's first
conversationalists:fish. But as they began to fill the seas with
conversationalists:croaks and honks and growls, corals were already there,
conversationalists:silently building reefs. Places for the fish and now many other
conversationalists:animals to call home.
conversationalists:Dr. Tim Lamont: Coral reefs are some of the world's most diverse
conversationalists:and special and beautiful and unique ecosystems.
Amy Martin:Welcome to Threshold, I'm Amy Martin, and
Amy Martin:this is Dr Tim Lamont, one of the world's leading experts in
Amy Martin:coral reef acoustics.
Amy Martin:Dr. Tim Lamont: I study coral reefs, their degradation, and
Amy Martin:more positively, efforts we can make to restore them.
Amy Martin:There are few habitats on our planet more
Amy Martin:wondrous than coral reefs, or more endangered. They're marine
Amy Martin:metropolises, underwater fountains of biodiversity, and
Amy Martin:they're in big trouble. You've probably heard about how rising
Amy Martin:ocean temperatures are starving and killing the coral, leaving
Amy Martin:many reefs bleached and broken. But what might be less well
Amy Martin:known is how important sound is in the coral reef story.
Amy Martin:Dr. Tim Lamont: When reefs are degraded, you can hear it
Amy Martin:happening. They go silent. And when reefs recover, or when
Amy Martin:reefs are restored, you can hear the noise coming back.
Amy Martin:Even though corals themselves are very quiet
Amy Martin:beings, through the communities they create, they are speaking.
Amy Martin:And if we can learn how to listen, we might have a chance
Amy Martin:of getting them through this time of crisis.
Amy Martin:It's just before sunrise, and I'm standing on a beach in Coral
Amy Martin:Bay, Western Australia, looking out toward Ningaloo Reef. The
Amy Martin:reef itself is hidden beneath the waves, but I can still see
Amy Martin:its protective power the way it absorbs the relentless force of
Amy Martin:the ocean crashing against it, leaving a buffer zone of calmer
Amy Martin:water close to shore.
Amy Martin:What you see from shore is a white line where waves are
Amy Martin:breaking pretty much as far as the eye can see out there.
Amy Martin:Ningaloo Reef stretches 260 kilometers, or around 160 miles
Amy Martin:end to end, and later I'm gonna take a boat out to it and go
Amy Martin:snorkeling. And I can't wait to see it up close, because it
Amy Martin:boggles my mind that something this big and tough could be made
Amy Martin:by an animal as small and soft as a boiled pea.
Amy Martin:Dr. Tim Lamont: They're are an ecosystem that is unique in the
Amy Martin:sense that it's made by an animal. It's got an animal right
Amy Martin:at the very base of it that constructs the whole habitat.
Amy Martin:Again, that's marine biologist Tim Lamont. He's based
Amy Martin:at Lancaster University in the UK. In our first episode, we
Amy Martin:heard about how some microbes make rocks called stromatolites.
Amy Martin:Corals took that technology and leveled it up.
Amy Martin:Dr. Tim Lamont: A coral is a tiny animal that forms these
Amy Martin:vast colonies and these colonies create rock. They create and
Amy Martin:exude limestone skeletons beneath them, and those
Amy Martin:skeletons grow in tropical shallow waters and create these
Amy Martin:wonderful shapes and patterns and structures around which all
Amy Martin:sorts of other life congregates and lives and makes a home.
Amy Martin:And corals actually provide housing inside their
Amy Martin:bodies too. Tiny algae called zooxanthellae live inside coral
Amy Martin:polyps in exchange they provide food and esthetic services to
Amy Martin:the corals.
Amy Martin:Dr. Tim Lamont: Corals themselves aren't colorful, it's
Amy Martin:the. Algae that lives inside them that gives them their
Amy Martin:color.
Amy Martin:So corals are kind of animal, vegetable and
Amy Martin:mineral, all in one. Their lives are defined by togetherness,
Amy Martin:from the symbiotic relationship that sustains each individual
Amy Martin:polyp all the way up to the enormous communities they build.
Amy Martin:Not all reefs are made by coral. They can be made of stone, sand,
Amy Martin:even the shells of oysters, but tropical coral reefs are the
Amy Martin:rain forests of the sea. They're bursting with life and sound.
Amy Martin:Dr. Tim Lamont: Absolutely, there's loads of different
Amy Martin:sounds. And that makes sense, because underwater sound travels
Amy Martin:so well. So if you're an animal that lives in the water, sound
Amy Martin:is a brilliant means by which to communicate, means by which to
Amy Martin:discover things about your environment around you.
Amy Martin:This is the sound of a reef in Indonesia.
Amy Martin:Dr. Tim Lamont: So the dominant sound you hear is this, this
Amy Martin:crackle, and that's actually the sound of snapping shrimp. They
Amy Martin:make that that sound with their claws.
Amy Martin:These claw clicks actually produce miniature shock
Amy Martin:waves that are strong enough to stun or even kill small fish.
Amy Martin:Dr. Tim Lamont: What you're hearing is loads and loads and
Amy Martin:loads of individual claw clicks, which, which combine to make
Amy Martin:that static sound. And then punctuated through that at
Amy Martin:different times of day, you'll hear different types of fish
Amy Martin:noises, and they're really quite varied as well. So there's
Amy Martin:buzzes and chatters and grunts and whoops and purrs, and some
Amy Martin:are high pitched and some are low pitched. Some are really
Amy Martin:loud, some are quite quiet.
Amy Martin:All of these sounds can tell us things about the
Amy Martin:health of the whole community. The sheer amount of sound and
Amy Martin:the diversity of it signals a thriving reef. And Tim and his
Amy Martin:colleagues are frequently stumped by what they hear
Amy Martin:underwater, just like Lauren Hawkins and Miles Parsons, who
Amy Martin:we met in our last episode.
Amy Martin:Dr. Tim Lamont: Again and again, we find ourselves just shrugging
Amy Martin:our shoulders, going no idea what makes that noise. Sometimes
Amy Martin:we joke that it's harder to think of anything we do know
Amy Martin:about coral reef sounds than thinking of stuff we don't know.
Amy Martin:And so it's a really exciting field to be involved with,
Amy Martin:because you know that the edge of knowledge is so close.
Amy Martin:I'm on the boat now with a small group of other
Amy Martin:tourists, all of us looking pretty awkward in our wetsuits
Amy Martin:and fins.
Amy Martin:So I'm heading out to Ningaloo Reef from Coral Bay. The sea is
Amy Martin:this unbelievable turquoise color.
Amy Martin:The plan for the morning is to do two swims, one on either side
Amy Martin:of the reef.
Amy Martin:And this is actually the first time I've ever gotten close to a
Amy Martin:reef. So I'm pretty excited.
Amy Martin:Soon we were there, and it was time for me to stop recording,
Amy Martin:get my snorkel in my mouth and jump in.
Amy Martin:Swimming through the coral jungles of Ningaloo was
Amy Martin:riveting. We started on the inland protected side where the
Amy Martin:water was relatively calm. Schools of brightly colored fish
Amy Martin:darted around me as I flutter kicked over a dazzling array of
Amy Martin:coral fingers, blossoms, plates and bulbs. It felt like swimming
Amy Martin:over a city made of flowers inhabited by fairy tale
Amy Martin:creatures, sea turtles, stingrays, sea stars. I even
Amy Martin:spotted a small shark darting through the forest of living
Amy Martin:stone.
Amy Martin:Dr. Tim Lamont: So many of your senses are just buzzing when
Amy Martin:you're underwater. You know, like what you can see, the
Amy Martin:shapes, the colors that the sense of busyness.
Amy Martin:I felt like I'd walked through the back of the
Amy Martin:wardrobe and floated into a magical world. I saw animals
Amy Martin:that looked like plants, plants that look like animals. If one
Amy Martin:of them had swum up to me and started talking, I wouldn't have
Amy Martin:been all that surprised. Anything seemed possible in this
Amy Martin:secret metropolis hidden just beneath the surface of my
Amy Martin:ordinary land based existence. Later we swam on the outer side
Amy Martin:of the reef where the full force of the ocean crashes in, and
Amy Martin:everything is loud and wild. I had to make sure the waves
Amy Martin:didn't throw me up against the coral. I could feel each swell
Amy Martin:growing, lifting me and the fish and anything else that wasn't
Amy Martin:anchored to the seabed, up and up, pushing us toward the reef
Amy Martin:faster and faster until the wave broke and we flowed back in the
Amy Martin:other direction, all of us utterly at the whim of the
Amy Martin:water. My arms and legs seem awkward and fragile. I've never
Amy Martin:felt more admiring of the easy grace of fish, and when an
Amy Martin:enormous manta ray swam past me, stately and serene, I don't have
Amy Martin:words to describe how that felt.
Amy Martin:Dr. Tim Lamont: It's staggering, isn't it? When I took my family
Amy Martin:to show them a coral reef, I took them to Ningaloo. It's so
Amy Martin:overwhelming some of the time that you know there's all of
Amy Martin:this life and activity and color and shape and sound all around
Amy Martin:you, and you're just there, like floating in the middle of it
Amy Martin:all, like some you know, big, clumsy oaf.
Amy Martin:Exactly!
Amy Martin:Tropical coral reefs cover a tiny percentage of the sea
Amy Martin:floor, 0.1% to be exact, but they support the lives of at
Amy Martin:least a quarter of ocean species. From microscopic
Amy Martin:plankton to massive whale sharks, the life giving power of
Amy Martin:reefs spirals up through the food chain and out in all
Amy Martin:directions, including up onto land and into our human lives.
Amy Martin:Billions of people across the globe depend on reefs for the
Amy Martin:seafood they nurture, the coastlines they protect, and the
Amy Martin:medicines they provide. The World Economic Forum estimates
Amy Martin:coral reefs are providing at least ten trillion dollars worth
Amy Martin:of services to humanity every year. But so much of what's
Amy Martin:precious about a reef can't be translated into money. All
Amy Martin:around the warm midline of our planet, people's lives are bound
Amy Martin:to reefs through food, language, stories, songs and spirituality.
Amy Martin:And as Tim talks, it's evident how much these places mean to
Amy Martin:him, too.
Amy Martin:Dr. Tim Lamont: And there's, there's still a lot that we have
Amy Martin:yet to appreciate about these places as well, that they're
Amy Martin:places where we have a very limited understanding of some
Amy Martin:aspects of reefs. We're discovering new things about
Amy Martin:coral reefs all the time and, and to, yeah, to think, to think
Amy Martin:of these places as being as vulnerable as they are is quite
Amy Martin:sobering. I find it really quite quite difficult to think about
Amy Martin:sometimes.
Amy Martin:I find it quite difficult to think about too.
Amy Martin:But the fact is, coral reefs are gravely threatened, and we need
Amy Martin:to face this reality if we're going to do anything about it.
Amy Martin:So I asked him to give us a general outline on coral reef
Amy Martin:health, and he responds a bit like a physician giving a really
Amy Martin:tough diagnosis to a patient.
Amy Martin:Dr. Tim Lamont: Coral reefs are facing more threats now than
Amy Martin:they have at any other point in human history, and we generally
Amy Martin:split them into what we call global threats and local
Amy Martin:threats. And so global threats are to do with climate change.
Amy Martin:And so they are coral bleaching, which is caused by extremes in
Amy Martin:temperature. More often than not, it's marine heat waves that
Amy Martin:cause the temperature of the water to rise that causes a
Amy Martin:breakdown in the relationship between the algae that lives
Amy Martin:inside the coral and the coral itself. The algae is expelled,
Amy Martin:and the coral can no longer photosynthesize, and often it
Amy Martin:will then starve and die a few weeks after that. Some marine
Amy Martin:heat waves are so intense that it's not the bleaching mechanism
Amy Martin:that kills the coral, it's, it's just akin to heat exhaustion.
Amy Martin:The coral basically just cooks instantly. So, so heat is a big
Amy Martin:problem. Climate change is also causing a worsening of these
Amy Martin:tropical storms and cyclones that are becoming more intense
Amy Martin:and more frequent, and so we're seeing storm damage go up. And
Amy Martin:then outside of climate change, in these local threats as well,
Amy Martin:we're seeing around the world increasing amounts of
Amy Martin:overfishing, of destructive fishing practices, of pollution.
Amy Martin:So there is a mixture of these big global climate change
Amy Martin:threats combined with these more localized threats from fishing
Amy Martin:and from pollution and from habitat destruction, and
Amy Martin:together that they paint a very bleak future for coral reefs.
Amy Martin:And it's not a future that is distant or is, you know,
Amy Martin:something that we have a lot of time to work out how to deal
Amy Martin:it's a future that is becoming a grim reality very quickly.
Amy Martin:Our oceans are heating up at an alarming rate.
Amy Martin:2023 was the hottest year in the ocean on record, until this
Amy Martin:year, when they got even hotter. As we release this episode at
Amy Martin:the end of 2024 we're in the middle of the largest coral
Amy Martin:bleaching event ever documented. Every light on the ocean
Amy Martin:temperature dashboard is flashing red. The latest science
Amy Martin:indicates that if average global temperatures rise to 1.5 degrees
Amy Martin:Celsius, more than 90% of coral reefs will be lost, and if we go
Amy Martin:past that, to two degrees of warming, almost all of them will
Amy Martin:likely die. We're currently on track for three degrees of
Amy Martin:warming by the end of this century.
Amy Martin:Dr. Tim Lamont: A reef has some natural resilience and is able
Amy Martin:to bounce back from some disturbance, and that's part of
Amy Martin:what a reef should be. It can't deal with the amount of
Amy Martin:disturbance we're throwing at it and the acceleration of the
Amy Martin:pressures that we're throwing at it as as humanity at the moment.
Amy Martin:These pressures change the soundscape of a reef
Amy Martin:like a sonic fingerprint left at the scene of a crime. This is a
Amy Martin:healthy reef full of color and bustling with the sounds of
Amy Martin:life.
Amy Martin:And here is a reef in peril, going pale and very quiet.
Amy Martin:How do you keep yourself sane, like you're obviously a person
Amy Martin:who cares about all of this and you're right in the water
Amy Martin:watching really hard things happen, and as you said, it's
Amy Martin:not, it's not in the future, it's now. How are you managing
Amy Martin:just the emotional impact of dealing with all of this?
Amy Martin:Dr. Tim Lamont: Sometimes it's difficult. That's the first
Amy Martin:thing to say, is that I wouldn't say that I manage it
Amy Martin:particularly well all of the time. Sometimes I do find it
Amy Martin:very hard, and I find it a particular challenge of my job.
Amy Martin:But that said, you know, lots of people have jobs where they work
Amy Martin:in difficult circumstances. You know, people who work in
Amy Martin:healthcare, people who work in emergency services, fields of
Amy Martin:work where you have to learn how to face difficult stuff in your
Amy Martin:job and then come home and not let it ruin your life.
Amy Martin:I think Tim does work in emergency services, just
Amy Martin:not in the way we typically define that term. And like any
Amy Martin:healthcare worker, he doesn't just want to document decline.
Amy Martin:He wants to try to keep coral reefs alive.
Amy Martin:Dr. Tim Lamont: Personally, I try and work on solutions. So
Amy Martin:whether that's working to try and improve the feasibility of
Amy Martin:restoration, whether that's trying to work with people in
Amy Martin:power, in businesses or in politics or in powerful social
Amy Martin:movements. So I think it's a mixture of learning to deal with
Amy Martin:work in tough circumstances, which is something that a lot of
Amy Martin:people do, and also trying to alter the course of our work
Amy Martin:such that it is moving towards positive solutions, rather than
Amy Martin:just describing depressing trends.
Amy Martin:After seeing too many reefs go ghostly white and
Amy Martin:hearing them turn deadly quiet, Tim was determined to find ways
Amy Martin:to help. He knew reefs were incredibly dynamic, places that
Amy Martin:can sometimes respond quickly to positive impacts, just like they
Amy Martin:do to negative ones.
Amy Martin:Dr. Tim Lamont: The propensity these ecosystems have to change,
Amy Martin:I find, is really amazing.
Amy Martin:And he began to wonder if he could use sound to
Amy Martin:help reefs ward off decline or even come back from the dead.
Amy Martin:Dr. Tim Lamont: It's this idea that by playing the right
Amy Martin:sounds, you can make places sound attractive to animals, and
Amy Martin:they'll then, you know, alter their behavior. You'll get
Amy Martin:increased settlement, increased immigration, if you like.
Amy Martin:We'll have more after this short break.
Amy Martin:Hey, I want to take a minute to thank you for listening to
Amy Martin:Threshold and to explain how important you are in getting the
Amy Martin:show made. Most podcasts raise money by selling advertising,
Amy Martin:and that pushes them to make a lot of episodes as quickly as
Amy Martin:possible. But that's just not who we are. Our show is about
Amy Martin:thinking deeply about how humans are fitting into the rest of the
Amy Martin:web of life. We take you places and craft stories that are
Amy Martin:intellectually challenging and emotionally rich. That's the
Amy Martin:kind of show we want to make, and that's the kind of show
Amy Martin:you've told us you want to hear. That's why we created an
Amy Martin:independent, non-profit media company, and why nearly all of
Amy Martin:our funding comes from listeners like you. This is not the
Amy Martin:easiest way of funding a show, but it is the way that's most
Amy Martin:aligned with our mission, and it's worked so far, thanks to
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Amy Martin:the donate button and give what you can. And again, thank you so
Amy Martin:much for listening.
Dallas Taylor:I'm Dallas Taylor, host of 20,000 Hertz, a
Dallas Taylor:podcast that reveals the untold stories behind the sounds of our
Dallas Taylor:world. We've uncovered the incredible intelligence of
Dallas Taylor:talking parrots.
Unknown:Basically, bird brain was a pejorative term, and here
Unknown:I had this bird that was doing the same types of tasks as the
Unknown:primates.
Dallas Taylor:We've investigated the bonding power
Dallas Taylor:of music.
Dallas Taylor:There's an intimacy there in communicating through the medium
Dallas Taylor:of music that can be really a powerful force for bringing
Dallas Taylor:people together.
Dallas Taylor:We've explored the subtle nuances of the human voice.
Unknown:We have to remember that humans, over many hundreds
Unknown:of thousands of years of evolution have become extremely
Unknown:attuned to the sounds of each other's voices.
Dallas Taylor:And we've revealed why a famous composer
Dallas Taylor:wrote a piece made entirely of silence.
Unknown:I think that's a really, potentially quite useful
Unknown:and quite profound experience to have.
Dallas Taylor:Subscribe to 20,000 Hertz right here in your
Dallas Taylor:podcast player. I'll meet you there.
Amy Martin:Hi Threshold listeners, do you ever find
Amy Martin:yourself wondering what businesses are doing and what
Amy Martin:more they should do to confront climate change? Then you should
Amy Martin:check out Climate Rising, the award winning podcast from
Amy Martin:Harvard Business School. Climate Rising gives you a behind the
Amy Martin:scenes look at how top business leaders are taking on the
Amy Martin:challenge of climate change. The show covers cutting edge
Amy Martin:solutions, from leveraging AI and carbon markets, to sharing
Amy Martin:stories that inspire climate action. Recent episodes feature
Amy Martin:insightful conversations with leaders like Netflix's first
Amy Martin:sustainability officer, Emma Stewart, who discusses how the
Amy Martin:global entertainment giant uses its platform to promote climate
Amy Martin:awareness. You'll also hear from CNN's chief climate
Amy Martin:correspondent, Bill Weir, about the importance of integrating
Amy Martin:climate change into news coverage. Each episode dives
Amy Martin:deep into the challenges and opportunities that climate
Amy Martin:change presents to entrepreneurs and innovators. Listen to
Amy Martin:Climate Rising every other Wednesday on Apple podcasts,
Amy Martin:Spotify, or wherever you get your podcasts.
Amy Martin:Welcome back to Threshold, I'm Amy Martin, and it's a November
Amy Martin:night. The moon is just past full, and the corals are
Amy Martin:spawning.
Amy Martin:Dr. Tim Lamont: It's this amazing night to be out in the
Amy Martin:water, swimming around.
Amy Martin:Marine Biologist Tim Lamont has an idea for how sound
Amy Martin:could be used to help coral push back against all the threats
Amy Martin:they're facing, and to understand how it works, we have
Amy Martin:to start here, during a spawning event, when millions of tiny
Amy Martin:corals release their eggs and sperm into the water.
Amy Martin:Dr. Tim Lamont: In many species, they all align, which is quite a
Amy Martin:magical thing. So on one night of the year, many of these
Amy Martin:broadcast spawners will all release their gametes all at the
Amy Martin:same time, and of course, that maximizes the chance that they
Amy Martin:meet in the water.
Amy Martin:Tim says, nobody knows for sure how the corals
Amy Martin:manage to coordinate this way. They just know that it happens.
Amy Martin:Dr. Tim Lamont: You can see the tiny little egg bundles floating
Amy Martin:up into the water, and you can see the sperm being released
Amy Martin:that creates such a buzz in activity around the reef,
Amy Martin:because there's so many other animals that then also come out
Amy Martin:to feed on these eggs and the sperm and, you know, it's chaos
Amy Martin:in the water. It's really loud, it's really busy. There's all
Amy Martin:sorts of stuff swimming around. It's going in your ears, it's
Amy Martin:going in your mask, it's going down your wetsuits. It's like,
Amy Martin:yeah, busiest night on the reef. It's like, Saturday night, city
Amy Martin:center, you know?
Amy Martin:Amidst all of this ruckus, some of the eggs manage
Amy Martin:to get fertilized and survive, and eventually a baby coral is
Amy Martin:born, small as a grain of sand, bobbing around in the open
Amy Martin:ocean.
Amy Martin:Dr. Tim Lamont: Then they come back to the reef, swept on ocean
Amy Martin:currents, and settle. So these free swimming coral planulae, as
Amy Martin:we call them, before they've settled, settle and become an
Amy Martin:adult coral polyp. And that's how you create a coral reef with
Amy Martin:millions and millions of those coral polyps.
Amy Martin:It's called a biphasic life cycle. Birth and
Amy Martin:early development spent out in the open ocean, adulthood spent
Amy Martin:on the reef.
Amy Martin:Dr. Tim Lamont: Corals have it in, other invertebrates have it,
Amy Martin:even the fish have it. As an egg or as a very young juvenile
Amy Martin:they'll be out at sea, and then there'll be this sort of journey
Amy Martin:back to the reef when the organism is ready to start its
Amy Martin:adult life. Animals arrive carry on ocean currents and settle in
Amy Martin:new places. Corals will settle and start to create habitat.
Amy Martin:Different types of algae will settle. Fishes will arrive, and
Amy Martin:you can get a community developing based on new arrivals
Amy Martin:from the open ocean, if you like.
Amy Martin:Creating a healthy reef is a cooperative process
Amy Martin:with interdependencies radiating out in all directions. The coral
Amy Martin:structures provide great hiding places for fish that are trying
Amy Martin:to hunt or avoid being hunted. The fish return the favor by
Amy Martin:peeing and pooping on the reef, providing nutrients that are
Amy Martin:crucial for the coral and the zooxanthellae inside of them.
Amy Martin:The fish also eat some other kinds of algae that would
Amy Martin:otherwise smother the coral. They kind of mow the lawn,
Amy Martin:clearing space for new coral polyps to settle. So healthy
Amy Martin:coral makes for healthier fish populations, which makes for
Amy Martin:healthier algae, which makes for healthier coral, and on and on,
Amy Martin:the fates of all the plants and animals here are tangled up
Amy Martin:together. So that's why listening to fish can help us
Amy Martin:understand what's happening with corals. Tim knew that sound was
Amy Martin:a part of this community building process that young fish
Amy Martin:listen out for the symphony of pops, whoops and gurgles of a
Amy Martin:thriving reef in deciding where to settle. But he wanted to know
Amy Martin:if that process could be hacked. When a reef was in decline,
Amy Martin:could he intervene acoustically and prevent it from going
Amy Martin:silent? Finding out meant becoming a reef DJ pumping out
Amy Martin:tunes designed to get the party started.
Amy Martin:Dr. Tim Lamont: When we first tried this, I was doing my PhD,
Amy Martin:so it was very low budget science. It was a lot of fun
Amy Martin:putting it all together. So the first experiment we did, we had
Amy Martin:these loudspeakers about the size of a dinner plate. They're
Amy Martin:sold as the loudspeakers that you would use to put in the
Amy Martin:swimming pool for synchronized swimming, so that the swimmers
Amy Martin:can hear the music, right?
Amy Martin:I just instantly saw all these fish in the line.
Amy Martin:Dr. Tim Lamont: It's all very little mermaid, isn't it?
Amy Martin:These speakers were connected to little floating
Amy Martin:barrels that held mp3 players.
Amy Martin:Dr. Tim Lamont: Which played one of our recordings of a really
Amy Martin:healthy sounding reef out to the loudspeaker.
Amy Martin:The next step was to tie the speakers to little
Amy Martin:artificial patches of habitat made by Tim and his team.
Amy Martin:Dr. Tim Lamont: Piles of rocks underwater, basically.
Amy Martin:Then they pushed play and waited for someone to
Amy Martin:show up.
Amy Martin:Dr. Tim Lamont: Repeatedly, repeatedly each day we go back
Amy Martin:and visit these reefs and count the number of fish that had
Amy Martin:arrived, that had settled. You know, I'd go down with a
Amy Martin:clipboard and and it was fun. It was like watching the
Amy Martin:establishment of a tiny little settlement so underwater, yeah,
Amy Martin:you know, you'd put your dive gear on, roll off the boat and
Amy Martin:go down and wonder, you know, who's moved in today? And we
Amy Martin:found that on the reefs where we were playing the healthy sounds,
Amy Martin:twice as many fish would move in. The community developed at
Amy Martin:twice the speed, and after 40 days, that was twice the
Amy Martin:abundance of fish.
Amy Martin:In other words, it worked. Hearing the buzz of a
Amy Martin:party made more fish want to come in and hang out.
Amy Martin:Dr. Tim Lamont: So if we play the sound of a healthy
Amy Martin:ecosystem, then that is a very attractive sound, and that
Amy Martin:literally calls in animals looking for somewhere to live.
Amy Martin:Tim's research gave us a new tool in the reef
Amy Martin:restoration toolbox.
Amy Martin:Dr. Tim Lamont: What we have is a short term proof of concept
Amy Martin:experiment. In that location, at that time, we're able to double
Amy Martin:fish abundance. There are a lot of other questions about whether
Amy Martin:that would work in different geographical contexts, on
Amy Martin:different reefs over longer periods of time, over larger
Amy Martin:spatial scales, and we don't know the answers to that yet.
Amy Martin:There are exciting experiments and studies going on around the
Amy Martin:world to try and get those answers, and time will tell what
Amy Martin:the results of those experiments will be.
Amy Martin:But what about the animals at the base of all this,
Amy Martin:the corals themselves? Is it possible that they could be
Amy Martin:encouraged to settle by playing the sounds of a healthy reef? On
Amy Martin:the face of it, this seems improbable. Corals have no ears
Amy Martin:or even brains, but Tim has learned not to make assumptions.
Amy Martin:Dr. Tim Lamont: Corals, especially in their little
Amy Martin:larval stage, are constantly surprising us with what they can
Amy Martin:do.
Amy Martin:And one of the intriguing things about the
Amy Martin:coral planulae, those free floating newborn corals, is that
Amy Martin:they're covered in microscopic hairs.
Amy Martin:Dr. Tim Lamont: And when you look at those hairs, they're
Amy Martin:actually relatively similar in structure to the hairs that are
Amy Martin:on the inside of our ears as mammals.
Amy Martin:They're called cilia, and in humans, they play
Amy Martin:an essential role in hearing. They grow deep inside the ear,
Amy Martin:swaying and bending as sound waves hit them and helping to
Amy Martin:translate that mechanical energy into chemical and electrical
Amy Martin:signals that can be processed by our brains. And the cilia on the
Amy Martin:bodies of baby corals seem to behave in very similar ways.
Amy Martin:Dr. Tim Lamont: These hairs will vibrate in response to a passing
Amy Martin:sound wave, and when we've studied these coral, planulae in
Amy Martin:labs, people have discovered that they will change their
Amy Martin:shape in response to the sound of a healthy reef. They'll
Amy Martin:change their shape to one that sinks in the water.
Amy Martin:The research on this is still emerging, but it seems
Amy Martin:that when the sound of a lively reef is nearby, the planulae
Amy Martin:will morph into a shape that helps them sink down into the
Amy Martin:water where they're more likely to find a good place to call
Amy Martin:home.
Amy Martin:Dr. Tim Lamont: If you put them in a tube, and you play the
Amy Martin:sound of a healthy reef from one end of that tube, they'll even
Amy Martin:start to swim down that tube towards the loudspeaker.
Amy Martin:These tiny infant corals are somehow queuing into
Amy Martin:the hubbub of a reef. It's like their bodies become ears bobbing
Amy Martin:along in the ocean. Half a billion years ago, long before
Amy Martin:anything was calling or crying or singing, these little beings
Amy Martin:may have been learning to listen.
Amy Martin:So just to be clear about what we know and what we have yet to
Amy Martin:find out here, we know that baby corals definitely respond to
Amy Martin:reef sounds in the lab and inside containers anchored to
Amy Martin:the sea floor. Whether or not those planulae are using sound
Amy Martin:to find and settle on reefs when they're swimming freely in the
Amy Martin:wilds of the ocean is still an open question. But again, Tim
Amy Martin:has learned that these ancient creatures shouldn't be
Amy Martin:underestimated.
Unknown:So there's some really quite amazing abilities of
Unknown:these, you know, animals that initially appear to be very
Unknown:simple, but are able to respond to these complex acoustic cues
Unknown:in their environments around them.
Amy Martin:New research on coral reef acoustics is coming
Amy Martin:out all the time, but so are new reports of dying reefs. We need
Amy Martin:legions of scientists like Tim, people who are willing to commit
Amy Martin:their lives to finding out everything we can about coral
Amy Martin:reefs and acting on that knowledge as quickly as
Amy Martin:possible, but scientists can only do so much. We're in a race
Amy Martin:against time, or more accurately, against ourselves.
Amy Martin:You are nurturing this extremely important habitat in this
Amy Martin:absolute time of crisis. Maybe if we can get some version of
Amy Martin:them through the next 30, 60, 150 years, then maybe there's a
Amy Martin:chance for them to get through this bottleneck. And do you see
Amy Martin:yourself that way, as like a coral shepherd moving them
Amy Martin:through a bottleneck?
Amy Martin:Dr. Tim Lamont: That I guess, is where, where this comes to roost
Amy Martin:is a story that involves everybody. The local efforts
Amy Martin:that we have can only really work within the parameters of
Amy Martin:the direction of global change. And you know, the climate story
Amy Martin:will be one that writes the narrative in the long term for
Amy Martin:all of this.
Amy Martin:So we need all of these efforts all at once.
Amy Martin:Hands-on, long-term, science-driven restoration
Amy Martin:projects adapted to the specific needs of different ecosystems.
Amy Martin:But those things won't be enough on their own. We also have to
Amy Martin:decide as a global community if we want to keep burning fossil
Amy Martin:fuels or if we want to have coral reefs, because we can't
Amy Martin:have both.
Amy Martin:Dr. Tim Lamont: Reefs are valuable. Even outside of what
Amy Martin:they provide to humanity, they're fantastically beautiful,
Amy Martin:diverse and unique living structures. I think it would be
Amy Martin:a terrible, terrible indictment of humanity if we didn't do
Amy Martin:everything in our power to protect them.
Amy Martin:Corals are survivors. For hundreds of
Amy Martin:millions of years, they've been a keystone species, creators of
Amy Martin:vital habitat that helped our planet transition from desolate
Amy Martin:silence to cacophonous life. But this wild flourishing didn't
Amy Martin:have to happen, and there's no guarantee that it will continue.
Amy Martin:Life on Earth is resilient, but it's not inevitable, and it's
Amy Martin:not indestructible.
Amy Martin:This episode of Threshold was written, reported and produced
Amy Martin:by me, Amy Martin, with help from Erika Janik and Sam Moore.
Amy Martin:Music by Todd Sickafoose. Post production by Alan Douches, fact
Amy Martin:checking by Sam Moore. The sounds of coral reefs and the
Amy Martin:fish you heard in this episode were generously provided by Tim
Amy Martin:Lamont and the following scientists, Ben Williams, Emma
Amy Martin:Weschke, Eric Parmentier, Isla Keesje Davidson and Steve
Amy Martin:Simpson. Big thanks to all of them. This show is made by
Amy Martin:Auricle Productions, a nonprofit organization powered by listener
Amy Martin:donations. Deneen eiske is our executive director. You can find
Amy Martin:out more about our show at thresholdpodcast.org.
