December 3, 2024 • 36 mins
Coral reefs are some of our planet’s most beautiful and biodiverse habitats. They’re also rich with sound, a bustling marine metropolis whose future is severely threatened by climate change. In this episode, we discover the important role of listening in coral communities.
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Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Amy Martin (00:00):
In the beginning, it was quiet. There were currents
(00:05):
and waves, downpours, fractures,eruptions, and eventually, the
burble of oxygen being releasedby communities of microbes in
the sea. But it took almost 4billion years for the first
(00:26):
complex life forms to emerge onEarth. They were soft bodied
things, jellies, sponges, seaanemones and corals. None of
them were big talkers. Last timewe met earth's first
conversationalists (00:46):
fish. But as they began to fill the seas with
croaks and honks and growls,corals were already there,
silently building reefs. Placesfor the fish and now many other
animals to call home.
Dr. Tim Lamont (01:06):
Coral reefs are some of the world's most diverse
and special and beautiful andunique ecosystems.
Amy Martin (01:14):
Welcome to Threshold, I'm Amy Martin, and
this is Dr Tim Lamont, one ofthe world's leading experts in
coral reef acoustics.
Dr. Tim Lamont (01:23):
I study coral reefs, their degradation, and
more positively, efforts we canmake to restore them.
Amy Martin (01:31):
There are few habitats on our planet more
wondrous than coral reefs, ormore endangered. They're marine
metropolises, underwaterfountains of biodiversity, and
they're in big trouble. You'veprobably heard about how rising
ocean temperatures are starvingand killing the coral, leaving
(01:52):
many reefs bleached and broken.But what might be less well
known is how important sound isin the coral reef story.
Dr. Tim Lamont (02:00):
When reefs are degraded, you can hear it
happening. They go silent. Andwhen reefs recover, or when
reefs are restored, you can hearthe noise coming back.
Amy Martin (02:11):
Even though corals themselves are very quiet
beings, through the communitiesthey create, they are speaking.
And if we can learn how tolisten, we might have a chance
of getting them through thistime of crisis.
(02:58):
It's just before sunrise, andI'm standing on a beach in Coral
Bay, Western Australia, lookingout toward Ningaloo Reef. The
reef itself is hidden beneaththe waves, but I can still see
its protective power the way itabsorbs the relentless force of
the ocean crashing against it,leaving a buffer zone of calmer
(03:19):
water close to shore.
What you see from shore is awhite line where waves are
breaking pretty much as far asthe eye can see out there.
Ningaloo Reef stretches 260kilometers, or around 160 miles
end to end, and later I'm gonnatake a boat out to it and go
snorkeling. And I can't wait tosee it up close, because it
(03:43):
boggles my mind that somethingthis big and tough could be made
by an animal as small and softas a boiled pea.
Dr. Tim Lamont (03:52):
They're are an ecosystem that is unique in the
sense that it's made by ananimal. It's got an animal right
at the very base of it thatconstructs the whole habitat.
Amy Martin (04:02):
Again, that's marine biologist Tim Lamont. He's based
at Lancaster University in theUK. In our first episode, we
heard about how some microbesmake rocks called stromatolites.
Corals took that technology andleveled it up.
Dr. Tim Lamont (04:18):
A coral is a tiny animal that forms these
vast colonies and these coloniescreate rock. They create and
exude limestone skeletonsbeneath them, and those
skeletons grow in tropicalshallow waters and create these
wonderful shapes and patternsand structures around which all
(04:39):
sorts of other life congregatesand lives and makes a home.
Amy Martin (04:43):
And corals actually provide housing inside their
bodies too. Tiny algae calledzooxanthellae live inside coral
polyps in exchange they providefood and esthetic services to
the corals.
Dr. Tim Lamont (04:57):
Corals themselves aren't colorful, it's
the. Algae that lives insidethem that gives them their
color.
Amy Martin (05:03):
So corals are kind of animal, vegetable and
mineral, all in one. Their livesare defined by togetherness,
from the symbiotic relationshipthat sustains each individual
polyp all the way up to theenormous communities they build.
Not all reefs are made by coral.They can be made of stone, sand,
(05:24):
even the shells of oysters, buttropical coral reefs are the
rain forests of the sea. They'rebursting with life and sound.
Dr. Tim Lamont (05:35):
Absolutely, there's loads of different
sounds. And that makes sense,because underwater sound travels
so well. So if you're an animalthat lives in the water, sound
is a brilliant means by which tocommunicate, means by which to
discover things about yourenvironment around you.
Amy Martin (05:51):
This is the sound of a reef in Indonesia.
Dr. Tim Lamont (05:55):
So the dominant sound you hear is this, this
crackle, and that's actually thesound of snapping shrimp. They
make that that sound with theirclaws.
Amy Martin (06:06):
These claw clicks actually produce miniature shock
waves that are strong enough tostun or even kill small fish.
Dr. Tim Lamont (06:14):
What you're hearing is loads and loads and
loads of individual claw clicks,which, which combine to make
that static sound. And thenpunctuated through that at
different times of day, you'llhear different types of fish
noises, and they're really quitevaried as well. So there's
buzzes and chatters and gruntsand whoops and purrs, and some
are high pitched and some arelow pitched. Some are really
(06:36):
loud, some are quite quiet.
Amy Martin (06:39):
All of these sounds can tell us things about the
health of the whole community.The sheer amount of sound and
the diversity of it signals athriving reef. And Tim and his
colleagues are frequentlystumped by what they hear
underwater, just like LaurenHawkins and Miles Parsons, who
we met in our last episode.
Dr. Tim Lamont (06:58):
Again and again, we find ourselves just shrugging
our shoulders, going no ideawhat makes that noise. Sometimes
we joke that it's harder tothink of anything we do know
about coral reef sounds thanthinking of stuff we don't know.
And so it's a really excitingfield to be involved with,
because you know that the edgeof knowledge is so close.
Amy Martin (07:22):
I'm on the boat now with a small group of other
tourists, all of us lookingpretty awkward in our wetsuits
and fins.
So I'm heading out to NingalooReef from Coral Bay. The sea is
this unbelievable turquoisecolor.
The plan for the morning is todo two swims, one on either side
(07:45):
of the reef.
And this is actually the firsttime I've ever gotten close to a
reef. So I'm pretty excited.
Soon we were there, and it wastime for me to stop recording,
get my snorkel in my mouth andjump in.
(08:06):
Swimming through the coraljungles of Ningaloo was
riveting. We started on theinland protected side where the
water was relatively calm.Schools of brightly colored fish
darted around me as I flutterkicked over a dazzling array of
coral fingers, blossoms, platesand bulbs. It felt like swimming
(08:28):
over a city made of flowersinhabited by fairy tale
creatures, sea turtles,stingrays, sea stars. I even
spotted a small shark dartingthrough the forest of living
stone.
Dr. Tim Lamont (08:42):
So many of your senses are just buzzing when
you're underwater. You know,like what you can see, the
shapes, the colors that thesense of busyness.
Amy Martin (08:52):
I felt like I'd walked through the back of the
wardrobe and floated into amagical world. I saw animals
that looked like plants, plantsthat look like animals. If one
of them had swum up to me andstarted talking, I wouldn't have
been all that surprised.Anything seemed possible in this
secret metropolis hidden justbeneath the surface of my
(09:15):
ordinary land based existence.Later we swam on the outer side
of the reef where the full forceof the ocean crashes in, and
everything is loud and wild. Ihad to make sure the waves
didn't throw me up against thecoral. I could feel each swell
(09:37):
growing, lifting me and the fishand anything else that wasn't
anchored to the seabed, up andup, pushing us toward the reef
faster and faster until the wavebroke and we flowed back in the
other direction, all of usutterly at the whim of the
water. My arms and legs seemawkward and fragile. I've never
(10:03):
felt more admiring of the easygrace of fish, and when an
enormous manta ray swam past me,stately and serene, I don't have
words to describe how that felt.
Dr. Tim Lamont (10:24):
It's staggering, isn't it? When I took my family
to show them a coral reef, Itook them to Ningaloo. It's so
overwhelming some of the timethat you know there's all of
this life and activity and colorand shape and sound all around
you, and you're just there, likefloating in the middle of it
all, like some you know, big,clumsy oaf.
Amy Martin (10:47):
Exactly!
Tropical coral reefs cover atiny percentage of the sea
floor, 0.1% to be exact, butthey support the lives of at
least a quarter of oceanspecies. From microscopic
plankton to massive whalesharks, the life giving power of
(11:09):
reefs spirals up through thefood chain and out in all
directions, including up ontoland and into our human lives.
Billions of people across theglobe depend on reefs for the
seafood they nurture, thecoastlines they protect, and the
medicines they provide. TheWorld Economic Forum estimates
(11:30):
coral reefs are providing atleast ten trillion dollars worth
of services to humanity everyyear. But so much of what's
precious about a reef can't betranslated into money. All
around the warm midline of ourplanet, people's lives are bound
to reefs through food, language,stories, songs and spirituality.
(11:54):
And as Tim talks, it's evidenthow much these places mean to
him, too.
Dr. Tim Lamont (11:59):
And there's, there's still a lot that we have
yet to appreciate about theseplaces as well, that they're
places where we have a verylimited understanding of some
aspects of reefs. We'rediscovering new things about
coral reefs all the time and,and to, yeah, to think, to think
of these places as being asvulnerable as they are is quite
(12:23):
sobering. I find it really quitequite difficult to think about
sometimes.
Amy Martin (12:29):
I find it quite difficult to think about too.
But the fact is, coral reefs aregravely threatened, and we need
to face this reality if we'regoing to do anything about it.
So I asked him to give us ageneral outline on coral reef
health, and he responds a bitlike a physician giving a really
(12:49):
tough diagnosis to a patient.
Dr. Tim Lamont (12:53):
Coral reefs are facing more threats now than
they have at any other point inhuman history, and we generally
split them into what we callglobal threats and local
threats. And so global threatsare to do with climate change.
And so they are coral bleaching,which is caused by extremes in
temperature. More often thannot, it's marine heat waves that
(13:17):
cause the temperature of thewater to rise that causes a
breakdown in the relationshipbetween the algae that lives
inside the coral and the coralitself. The algae is expelled,
and the coral can no longerphotosynthesize, and often it
will then starve and die a fewweeks after that. Some marine
(13:38):
heat waves are so intense thatit's not the bleaching mechanism
that kills the coral, it's, it'sjust akin to heat exhaustion.
The coral basically just cooksinstantly. So, so heat is a big
problem. Climate change is alsocausing a worsening of these
tropical storms and cyclonesthat are becoming more intense
(13:58):
and more frequent, and so we'reseeing storm damage go up. And
then outside of climate change,in these local threats as well,
we're seeing around the worldincreasing amounts of
overfishing, of destructivefishing practices, of pollution.
So there is a mixture of thesebig global climate change
(14:19):
threats combined with these morelocalized threats from fishing
and from pollution and fromhabitat destruction, and
together that they paint a verybleak future for coral reefs.
And it's not a future that isdistant or is, you know,
something that we have a lot oftime to work out how to deal
(14:40):
it's a future that is becoming agrim reality very quickly.
Amy Martin (14:46):
Our oceans are heating up at an alarming rate.
2023 was the hottest year in theocean on record, until this
year, when they got even hotter.As we release this episode at
the end of 2024 we're in themiddle of the largest coral
bleaching event ever documented.Every light on the ocean
(15:08):
temperature dashboard isflashing red. The latest science
indicates that if average globaltemperatures rise to 1.5 degrees
Celsius, more than 90% of coralreefs will be lost, and if we go
past that, to two degrees ofwarming, almost all of them will
(15:30):
likely die. We're currently ontrack for three degrees of
warming by the end of thiscentury.
Dr. Tim Lamont (15:40):
A reef has some natural resilience and is able
to bounce back from somedisturbance, and that's part of
what a reef should be. It can'tdeal with the amount of
disturbance we're throwing at itand the acceleration of the
pressures that we're throwing atit as as humanity at the moment.
Amy Martin (15:58):
These pressures change the soundscape of a reef
like a sonic fingerprint left atthe scene of a crime. This is a
healthy reef full of color andbustling with the sounds of
life.
(16:19):
And here is a reef in peril,going pale and very quiet.
How do you keep yourself sane,like you're obviously a person
who cares about all of this andyou're right in the water
(16:40):
watching really hard thingshappen, and as you said, it's
not, it's not in the future,it's now. How are you managing
just the emotional impact ofdealing with all of this?
Dr. Tim Lamont (16:53):
Sometimes it's difficult. That's the first
thing to say, is that I wouldn'tsay that I manage it
particularly well all of thetime. Sometimes I do find it
very hard, and I find it aparticular challenge of my job.
But that said, you know, lots ofpeople have jobs where they work
in difficult circumstances. Youknow, people who work in
(17:14):
healthcare, people who work inemergency services, fields of
work where you have to learn howto face difficult stuff in your
job and then come home and notlet it ruin your life.
Amy Martin (17:25):
I think Tim does work in emergency services, just
not in the way we typicallydefine that term. And like any
healthcare worker, he doesn'tjust want to document decline.
He wants to try to keep coralreefs alive.
Dr. Tim Lamont (17:45):
Personally, I try and work on solutions. So
whether that's working to tryand improve the feasibility of
restoration, whether that'strying to work with people in
power, in businesses or inpolitics or in powerful social
movements. So I think it's amixture of learning to deal with
(18:06):
work in tough circumstances,which is something that a lot of
people do, and also trying toalter the course of our work
such that it is moving towardspositive solutions, rather than
just describing depressingtrends.
Amy Martin (18:21):
After seeing too many reefs go ghostly white and
hearing them turn deadly quiet,Tim was determined to find ways
to help. He knew reefs wereincredibly dynamic, places that
can sometimes respond quickly topositive impacts, just like they
do to negative ones.
Dr. Tim Lamont (18:40):
The propensity these ecosystems have to change,
I find, is really amazing.
Amy Martin (18:46):
And he began to wonder if he could use sound to
help reefs ward off decline oreven come back from the dead.
Dr. Tim Lamont (18:55):
It's this idea that by playing the right
sounds, you can make placessound attractive to animals, and
they'll then, you know, altertheir behavior. You'll get
increased settlement, increasedimmigration, if you like.
Amy Martin (19:09):
We'll have more after this short break.
(19:31):
Hey, I want to take a minute tothank you for listening to
Threshold and to explain howimportant you are in getting the
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(19:52):
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(20:15):
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(20:37):
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much for listening.
Dallas Taylor (21:02):
I'm Dallas Taylor, host of 20,000 Hertz, a
podcast that reveals the untoldstories behind the sounds of our
world. We've uncovered theincredible intelligence of
talking parrots.
Unknown (21:14):
Basically, bird brain was a pejorative term, and here
I had this bird that was doingthe same types of tasks as the
primates.
Dallas Taylor (21:23):
We've investigated the bonding power
of music.
There's an intimacy there incommunicating through the medium
of music that can be really apowerful force for bringing
people together.
We've explored the subtlenuances of the human voice.
Unknown (21:38):
We have to remember that humans, over many hundreds
of thousands of years ofevolution have become extremely
attuned to the sounds of eachother's voices.
Dallas Taylor (21:46):
And we've revealed why a famous composer
wrote a piece made entirely ofsilence.
Unknown (21:51):
I think that's a really, potentially quite useful
and quite profound experience tohave.
Dallas Taylor (21:56):
Subscribe to 20,000 Hertz right here in your
podcast player. I'll meet youthere.
Amy Martin (22:02):
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(22:25):
solutions, from leveraging AIand carbon markets, to sharing
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(23:16):
Welcome back to Threshold, I'mAmy Martin, and it's a November
night. The moon is just pastfull, and the corals are
spawning.
Dr. Tim Lamont (23:26):
It's this amazing night to be out in the
water, swimming around.
Amy Martin (23:31):
Marine Biologist Tim Lamont has an idea for how sound
could be used to help coral pushback against all the threats
they're facing, and tounderstand how it works, we have
to start here, during a spawningevent, when millions of tiny
corals release their eggs andsperm into the water.
Dr. Tim Lamont (23:49):
In many species, they all align, which is quite a
magical thing. So on one nightof the year, many of these
broadcast spawners will allrelease their gametes all at the
same time, and of course, thatmaximizes the chance that they
meet in the water.
Amy Martin (24:05):
Tim says, nobody knows for sure how the corals
manage to coordinate this way.They just know that it happens.
Dr. Tim Lamont (24:12):
You can see the tiny little egg bundles floating
up into the water, and you cansee the sperm being released
that creates such a buzz inactivity around the reef,
because there's so many otheranimals that then also come out
to feed on these eggs and thesperm and, you know, it's chaos
in the water. It's really loud,it's really busy. There's all
sorts of stuff swimming around.It's going in your ears, it's
going in your mask, it's goingdown your wetsuits. It's like,
(24:35):
yeah, busiest night on the reef.It's like, Saturday night, city
center, you know?
Amy Martin (24:45):
Amidst all of this ruckus, some of the eggs manage
to get fertilized and survive,and eventually a baby coral is
born, small as a grain of sand,bobbing around in the open
ocean.
Dr. Tim Lamont (25:00):
Then they come back to the reef, swept on ocean
currents, and settle. So thesefree swimming coral planulae, as
we call them, before they'vesettled, settle and become an
adult coral polyp. And that'show you create a coral reef with
millions and millions of thosecoral polyps.
Amy Martin (25:17):
It's called a biphasic life cycle. Birth and
early development spent out inthe open ocean, adulthood spent
on the reef.
Dr. Tim Lamont (25:26):
Corals have it in, other invertebrates have it,
even the fish have it. As an eggor as a very young juvenile
they'll be out at sea, and thenthere'll be this sort of journey
back to the reef when theorganism is ready to start its
adult life. Animals arrive carryon ocean currents and settle in
new places. Corals will settleand start to create habitat.
(25:49):
Different types of algae willsettle. Fishes will arrive, and
you can get a communitydeveloping based on new arrivals
from the open ocean, if youlike.
Amy Martin (26:02):
Creating a healthy reef is a cooperative process
with interdependencies radiatingout in all directions. The coral
structures provide great hidingplaces for fish that are trying
to hunt or avoid being hunted.The fish return the favor by
peeing and pooping on the reef,providing nutrients that are
(26:22):
crucial for the coral and thezooxanthellae inside of them.
The fish also eat some otherkinds of algae that would
otherwise smother the coral.They kind of mow the lawn,
clearing space for new coralpolyps to settle. So healthy
coral makes for healthier fishpopulations, which makes for
healthier algae, which makes forhealthier coral, and on and on,
(26:46):
the fates of all the plants andanimals here are tangled up
together. So that's whylistening to fish can help us
understand what's happening withcorals. Tim knew that sound was
a part of this communitybuilding process that young fish
listen out for the symphony ofpops, whoops and gurgles of a
(27:08):
thriving reef in deciding whereto settle. But he wanted to know
if that process could be hacked.When a reef was in decline,
could he intervene acousticallyand prevent it from going
silent? Finding out meantbecoming a reef DJ pumping out
tunes designed to get the partystarted.
Dr. Tim Lamont (27:30):
When we first tried this, I was doing my PhD,
so it was very low budgetscience. It was a lot of fun
putting it all together. So thefirst experiment we did, we had
these loudspeakers about thesize of a dinner plate. They're
sold as the loudspeakers thatyou would use to put in the
swimming pool for synchronizedswimming, so that the swimmers
can hear the music, right?
Amy Martin (27:50):
I just instantly saw all these fish in the line.
Dr. Tim Lamont (27:54):
It's all very little mermaid, isn't it?
Amy Martin (27:58):
These speakers were connected to little floating
barrels that held mp3 players.
Dr. Tim Lamont (28:03):
Which played one of our recordings of a really
healthy sounding reef out to theloudspeaker.
Amy Martin (28:08):
The next step was to tie the speakers to little
artificial patches of habitatmade by Tim and his team.
Dr. Tim Lamont (28:14):
Piles of rocks underwater, basically.
Amy Martin (28:16):
Then they pushed play and waited for someone to
show up.
Dr. Tim Lamont (28:20):
Repeatedly, repeatedly each day we go back
and visit these reefs and countthe number of fish that had
arrived, that had settled. Youknow, I'd go down with a
clipboard and and it was fun. Itwas like watching the
establishment of a tiny littlesettlement so underwater, yeah,
you know, you'd put your divegear on, roll off the boat and
go down and wonder, you know,who's moved in today? And we
(28:43):
found that on the reefs where wewere playing the healthy sounds,
twice as many fish would movein. The community developed at
twice the speed, and after 40days, that was twice the
abundance of fish.
Amy Martin (29:00):
In other words, it worked. Hearing the buzz of a
party made more fish want tocome in and hang out.
Dr. Tim Lamont (29:09):
So if we play the sound of a healthy
ecosystem, then that is a veryattractive sound, and that
literally calls in animalslooking for somewhere to live.
Amy Martin (29:20):
Tim's research gave us a new tool in the reef
restoration toolbox.
Dr. Tim Lamont (29:25):
What we have is a short term proof of concept
experiment. In that location, atthat time, we're able to double
fish abundance. There are a lotof other questions about whether
that would work in differentgeographical contexts, on
different reefs over longerperiods of time, over larger
spatial scales, and we don'tknow the answers to that yet.
(29:46):
There are exciting experimentsand studies going on around the
world to try and get thoseanswers, and time will tell what
the results of those experimentswill be.
Amy Martin (29:55):
But what about the animals at the base of all this,
the corals themselves? Is itpossible that they could be
encouraged to settle by playingthe sounds of a healthy reef? On
the face of it, this seemsimprobable. Corals have no ears
or even brains, but Tim haslearned not to make assumptions.
Dr. Tim Lamont (30:16):
Corals, especially in their little
larval stage, are constantlysurprising us with what they can
do.
Amy Martin (30:21):
And one of the intriguing things about the
coral planulae, those freefloating newborn corals, is that
they're covered in microscopichairs.
Dr. Tim Lamont (30:30):
And when you look at those hairs, they're
actually relatively similar instructure to the hairs that are
on the inside of our ears asmammals.
Amy Martin (30:38):
They're called cilia, and in humans, they play
an essential role in hearing.They grow deep inside the ear,
swaying and bending as soundwaves hit them and helping to
translate that mechanical energyinto chemical and electrical
signals that can be processed byour brains. And the cilia on the
(31:00):
bodies of baby corals seem tobehave in very similar ways.
Dr. Tim Lamont (31:05):
These hairs will vibrate in response to a passing
sound wave, and when we'vestudied these coral, planulae in
labs, people have discoveredthat they will change their
shape in response to the soundof a healthy reef. They'll
change their shape to one thatsinks in the water.
Amy Martin (31:23):
The research on this is still emerging, but it seems
that when the sound of a livelyreef is nearby, the planulae
will morph into a shape thathelps them sink down into the
water where they're more likelyto find a good place to call
home.
Dr. Tim Lamont (31:39):
If you put them in a tube, and you play the
sound of a healthy reef from oneend of that tube, they'll even
start to swim down that tubetowards the loudspeaker.
Amy Martin (31:48):
These tiny infant corals are somehow queuing into
the hubbub of a reef. It's liketheir bodies become ears bobbing
along in the ocean. Half abillion years ago, long before
anything was calling or cryingor singing, these little beings
(32:09):
may have been learning tolisten.
So just to be clear about whatwe know and what we have yet to
find out here, we know that babycorals definitely respond to
reef sounds in the lab andinside containers anchored to
(32:31):
the sea floor. Whether or notthose planulae are using sound
to find and settle on reefs whenthey're swimming freely in the
wilds of the ocean is still anopen question. But again, Tim
has learned that these ancientcreatures shouldn't be
underestimated.
Unknown (32:49):
So there's some really quite amazing abilities of
these, you know, animals thatinitially appear to be very
simple, but are able to respondto these complex acoustic cues
in their environments aroundthem.
Amy Martin (33:02):
New research on coral reef acoustics is coming
out all the time, but so are newreports of dying reefs. We need
legions of scientists like Tim,people who are willing to commit
their lives to finding outeverything we can about coral
reefs and acting on thatknowledge as quickly as
possible, but scientists canonly do so much. We're in a race
(33:26):
against time, or moreaccurately, against ourselves.
You are nurturing this extremelyimportant habitat in this
absolute time of crisis. Maybeif we can get some version of
them through the next 30, 60,150 years, then maybe there's a
(33:49):
chance for them to get throughthis bottleneck. And do you see
yourself that way, as like acoral shepherd moving them
through a bottleneck?
Dr. Tim Lamont (33:56):
That I guess, is where, where this comes to roost
is a story that involveseverybody. The local efforts
that we have can only reallywork within the parameters of
the direction of global change.And you know, the climate story
will be one that writes thenarrative in the long term for
(34:17):
all of this.
Amy Martin (34:28):
So we need all of these efforts all at once.
Hands-on, long-term,science-driven restoration
projects adapted to the specificneeds of different ecosystems.
But those things won't be enoughon their own. We also have to
decide as a global community ifwe want to keep burning fossil
(34:50):
fuels or if we want to havecoral reefs, because we can't
have both.
Dr. Tim Lamont (34:58):
Reefs are valuable. Even outside of what
they provide to humanity,they're fantastically beautiful,
diverse and unique livingstructures. I think it would be
a terrible, terrible indictmentof humanity if we didn't do
everything in our power toprotect them.
Amy Martin (35:27):
Corals are survivors. For hundreds of
millions of years, they've beena keystone species, creators of
vital habitat that helped ourplanet transition from desolate
silence to cacophonous life. Butthis wild flourishing didn't
have to happen, and there's noguarantee that it will continue.
(35:53):
Life on Earth is resilient, butit's not inevitable, and it's
not indestructible.
(36:28):
This episode of Threshold waswritten, reported and produced
by me, Amy Martin, with helpfrom Erika Janik and Sam Moore.
Music by Todd Sickafoose. Postproduction by Alan Douches, fact
checking by Sam Moore. Thesounds of coral reefs and the
fish you heard in this episodewere generously provided by Tim
(36:49):
Lamont and the followingscientists, Ben Williams, Emma
Weschke, Eric Parmentier, IslaKeesje Davidson and Steve
Simpson. Big thanks to all ofthem. This show is made by
Auricle Productions, a nonprofitorganization powered by listener
donations. Deneen eiske is ourexecutive director. You can find
(37:11):
out more about our show atthresholdpodcast.org.
In the beginning, it was quiet. There were currents
(00:05):
and waves, downpours, fractures,eruptions, and eventually, the
burble of oxygen being releasedby communities of microbes in
the sea. But it took almost 4billion years for the first
(00:26):
complex life forms to emerge onEarth. They were soft bodied
things, jellies, sponges, seaanemones and corals. None of
them were big talkers. Last timewe met earth's first
conversationalists (00:46):
fish. But as they began to fill the seas with
croaks and honks and growls,corals were already there,
silently building reefs. Placesfor the fish and now many other
animals to call home.
Dr. Tim Lamont (01:06):
Coral reefs are some of the world's most diverse
and special and beautiful andunique ecosystems.
Amy Martin (01:14):
Welcome to Threshold, I'm Amy Martin, and
this is Dr Tim Lamont, one ofthe world's leading experts in
coral reef acoustics.
Dr. Tim Lamont (01:23):
I study coral reefs, their degradation, and
more positively, efforts we canmake to restore them.
Amy Martin (01:31):
There are few habitats on our planet more
wondrous than coral reefs, ormore endangered. They're marine
metropolises, underwaterfountains of biodiversity, and
they're in big trouble. You'veprobably heard about how rising
ocean temperatures are starvingand killing the coral, leaving
(01:52):
many reefs bleached and broken.But what might be less well
known is how important sound isin the coral reef story.
Dr. Tim Lamont (02:00):
When reefs are degraded, you can hear it
happening. They go silent. Andwhen reefs recover, or when
reefs are restored, you can hearthe noise coming back.
Amy Martin (02:11):
Even though corals themselves are very quiet
beings, through the communitiesthey create, they are speaking.
And if we can learn how tolisten, we might have a chance
of getting them through thistime of crisis.
(02:58):
It's just before sunrise, andI'm standing on a beach in Coral
Bay, Western Australia, lookingout toward Ningaloo Reef. The
reef itself is hidden beneaththe waves, but I can still see
its protective power the way itabsorbs the relentless force of
the ocean crashing against it,leaving a buffer zone of calmer
(03:19):
water close to shore.
What you see from shore is awhite line where waves are
breaking pretty much as far asthe eye can see out there.
Ningaloo Reef stretches 260kilometers, or around 160 miles
end to end, and later I'm gonnatake a boat out to it and go
snorkeling. And I can't wait tosee it up close, because it
(03:43):
boggles my mind that somethingthis big and tough could be made
by an animal as small and softas a boiled pea.
Dr. Tim Lamont (03:52):
They're are an ecosystem that is unique in the
sense that it's made by ananimal. It's got an animal right
at the very base of it thatconstructs the whole habitat.
Amy Martin (04:02):
Again, that's marine biologist Tim Lamont. He's based
at Lancaster University in theUK. In our first episode, we
heard about how some microbesmake rocks called stromatolites.
Corals took that technology andleveled it up.
Dr. Tim Lamont (04:18):
A coral is a tiny animal that forms these
vast colonies and these coloniescreate rock. They create and
exude limestone skeletonsbeneath them, and those
skeletons grow in tropicalshallow waters and create these
wonderful shapes and patternsand structures around which all
(04:39):
sorts of other life congregatesand lives and makes a home.
Amy Martin (04:43):
And corals actually provide housing inside their
bodies too. Tiny algae calledzooxanthellae live inside coral
polyps in exchange they providefood and esthetic services to
the corals.
Dr. Tim Lamont (04:57):
Corals themselves aren't colorful, it's
the. Algae that lives insidethem that gives them their
color.
Amy Martin (05:03):
So corals are kind of animal, vegetable and
mineral, all in one. Their livesare defined by togetherness,
from the symbiotic relationshipthat sustains each individual
polyp all the way up to theenormous communities they build.
Not all reefs are made by coral.They can be made of stone, sand,
(05:24):
even the shells of oysters, buttropical coral reefs are the
rain forests of the sea. They'rebursting with life and sound.
Dr. Tim Lamont (05:35):
Absolutely, there's loads of different
sounds. And that makes sense,because underwater sound travels
so well. So if you're an animalthat lives in the water, sound
is a brilliant means by which tocommunicate, means by which to
discover things about yourenvironment around you.
Amy Martin (05:51):
This is the sound of a reef in Indonesia.
Dr. Tim Lamont (05:55):
So the dominant sound you hear is this, this
crackle, and that's actually thesound of snapping shrimp. They
make that that sound with theirclaws.
Amy Martin (06:06):
These claw clicks actually produce miniature shock
waves that are strong enough tostun or even kill small fish.
Dr. Tim Lamont (06:14):
What you're hearing is loads and loads and
loads of individual claw clicks,which, which combine to make
that static sound. And thenpunctuated through that at
different times of day, you'llhear different types of fish
noises, and they're really quitevaried as well. So there's
buzzes and chatters and gruntsand whoops and purrs, and some
are high pitched and some arelow pitched. Some are really
(06:36):
loud, some are quite quiet.
Amy Martin (06:39):
All of these sounds can tell us things about the
health of the whole community.The sheer amount of sound and
the diversity of it signals athriving reef. And Tim and his
colleagues are frequentlystumped by what they hear
underwater, just like LaurenHawkins and Miles Parsons, who
we met in our last episode.
Dr. Tim Lamont (06:58):
Again and again, we find ourselves just shrugging
our shoulders, going no ideawhat makes that noise. Sometimes
we joke that it's harder tothink of anything we do know
about coral reef sounds thanthinking of stuff we don't know.
And so it's a really excitingfield to be involved with,
because you know that the edgeof knowledge is so close.
Amy Martin (07:22):
I'm on the boat now with a small group of other
tourists, all of us lookingpretty awkward in our wetsuits
and fins.
So I'm heading out to NingalooReef from Coral Bay. The sea is
this unbelievable turquoisecolor.
The plan for the morning is todo two swims, one on either side
(07:45):
of the reef.
And this is actually the firsttime I've ever gotten close to a
reef. So I'm pretty excited.
Soon we were there, and it wastime for me to stop recording,
get my snorkel in my mouth andjump in.
(08:06):
Swimming through the coraljungles of Ningaloo was
riveting. We started on theinland protected side where the
water was relatively calm.Schools of brightly colored fish
darted around me as I flutterkicked over a dazzling array of
coral fingers, blossoms, platesand bulbs. It felt like swimming
(08:28):
over a city made of flowersinhabited by fairy tale
creatures, sea turtles,stingrays, sea stars. I even
spotted a small shark dartingthrough the forest of living
stone.
Dr. Tim Lamont (08:42):
So many of your senses are just buzzing when
you're underwater. You know,like what you can see, the
shapes, the colors that thesense of busyness.
Amy Martin (08:52):
I felt like I'd walked through the back of the
wardrobe and floated into amagical world. I saw animals
that looked like plants, plantsthat look like animals. If one
of them had swum up to me andstarted talking, I wouldn't have
been all that surprised.Anything seemed possible in this
secret metropolis hidden justbeneath the surface of my
(09:15):
ordinary land based existence.Later we swam on the outer side
of the reef where the full forceof the ocean crashes in, and
everything is loud and wild. Ihad to make sure the waves
didn't throw me up against thecoral. I could feel each swell
(09:37):
growing, lifting me and the fishand anything else that wasn't
anchored to the seabed, up andup, pushing us toward the reef
faster and faster until the wavebroke and we flowed back in the
other direction, all of usutterly at the whim of the
water. My arms and legs seemawkward and fragile. I've never
(10:03):
felt more admiring of the easygrace of fish, and when an
enormous manta ray swam past me,stately and serene, I don't have
words to describe how that felt.
Dr. Tim Lamont (10:24):
It's staggering, isn't it? When I took my family
to show them a coral reef, Itook them to Ningaloo. It's so
overwhelming some of the timethat you know there's all of
this life and activity and colorand shape and sound all around
you, and you're just there, likefloating in the middle of it
all, like some you know, big,clumsy oaf.
Amy Martin (10:47):
Exactly!
Tropical coral reefs cover atiny percentage of the sea
floor, 0.1% to be exact, butthey support the lives of at
least a quarter of oceanspecies. From microscopic
plankton to massive whalesharks, the life giving power of
(11:09):
reefs spirals up through thefood chain and out in all
directions, including up ontoland and into our human lives.
Billions of people across theglobe depend on reefs for the
seafood they nurture, thecoastlines they protect, and the
medicines they provide. TheWorld Economic Forum estimates
(11:30):
coral reefs are providing atleast ten trillion dollars worth
of services to humanity everyyear. But so much of what's
precious about a reef can't betranslated into money. All
around the warm midline of ourplanet, people's lives are bound
to reefs through food, language,stories, songs and spirituality.
(11:54):
And as Tim talks, it's evidenthow much these places mean to
him, too.
Dr. Tim Lamont (11:59):
And there's, there's still a lot that we have
yet to appreciate about theseplaces as well, that they're
places where we have a verylimited understanding of some
aspects of reefs. We'rediscovering new things about
coral reefs all the time and,and to, yeah, to think, to think
of these places as being asvulnerable as they are is quite
(12:23):
sobering. I find it really quitequite difficult to think about
sometimes.
Amy Martin (12:29):
I find it quite difficult to think about too.
But the fact is, coral reefs aregravely threatened, and we need
to face this reality if we'regoing to do anything about it.
So I asked him to give us ageneral outline on coral reef
health, and he responds a bitlike a physician giving a really
(12:49):
tough diagnosis to a patient.
Dr. Tim Lamont (12:53):
Coral reefs are facing more threats now than
they have at any other point inhuman history, and we generally
split them into what we callglobal threats and local
threats. And so global threatsare to do with climate change.
And so they are coral bleaching,which is caused by extremes in
temperature. More often thannot, it's marine heat waves that
(13:17):
cause the temperature of thewater to rise that causes a
breakdown in the relationshipbetween the algae that lives
inside the coral and the coralitself. The algae is expelled,
and the coral can no longerphotosynthesize, and often it
will then starve and die a fewweeks after that. Some marine
(13:38):
heat waves are so intense thatit's not the bleaching mechanism
that kills the coral, it's, it'sjust akin to heat exhaustion.
The coral basically just cooksinstantly. So, so heat is a big
problem. Climate change is alsocausing a worsening of these
tropical storms and cyclonesthat are becoming more intense
(13:58):
and more frequent, and so we'reseeing storm damage go up. And
then outside of climate change,in these local threats as well,
we're seeing around the worldincreasing amounts of
overfishing, of destructivefishing practices, of pollution.
So there is a mixture of thesebig global climate change
(14:19):
threats combined with these morelocalized threats from fishing
and from pollution and fromhabitat destruction, and
together that they paint a verybleak future for coral reefs.
And it's not a future that isdistant or is, you know,
something that we have a lot oftime to work out how to deal
(14:40):
it's a future that is becoming agrim reality very quickly.
Amy Martin (14:46):
Our oceans are heating up at an alarming rate.
2023 was the hottest year in theocean on record, until this
year, when they got even hotter.As we release this episode at
the end of 2024 we're in themiddle of the largest coral
bleaching event ever documented.Every light on the ocean
(15:08):
temperature dashboard isflashing red. The latest science
indicates that if average globaltemperatures rise to 1.5 degrees
Celsius, more than 90% of coralreefs will be lost, and if we go
past that, to two degrees ofwarming, almost all of them will
(15:30):
likely die. We're currently ontrack for three degrees of
warming by the end of thiscentury.
Dr. Tim Lamont (15:40):
A reef has some natural resilience and is able
to bounce back from somedisturbance, and that's part of
what a reef should be. It can'tdeal with the amount of
disturbance we're throwing at itand the acceleration of the
pressures that we're throwing atit as as humanity at the moment.
Amy Martin (15:58):
These pressures change the soundscape of a reef
like a sonic fingerprint left atthe scene of a crime. This is a
healthy reef full of color andbustling with the sounds of
life.
(16:19):
And here is a reef in peril,going pale and very quiet.
How do you keep yourself sane,like you're obviously a person
who cares about all of this andyou're right in the water
(16:40):
watching really hard thingshappen, and as you said, it's
not, it's not in the future,it's now. How are you managing
just the emotional impact ofdealing with all of this?
Dr. Tim Lamont (16:53):
Sometimes it's difficult. That's the first
thing to say, is that I wouldn'tsay that I manage it
particularly well all of thetime. Sometimes I do find it
very hard, and I find it aparticular challenge of my job.
But that said, you know, lots ofpeople have jobs where they work
in difficult circumstances. Youknow, people who work in
(17:14):
healthcare, people who work inemergency services, fields of
work where you have to learn howto face difficult stuff in your
job and then come home and notlet it ruin your life.
Amy Martin (17:25):
I think Tim does work in emergency services, just
not in the way we typicallydefine that term. And like any
healthcare worker, he doesn'tjust want to document decline.
He wants to try to keep coralreefs alive.
Dr. Tim Lamont (17:45):
Personally, I try and work on solutions. So
whether that's working to tryand improve the feasibility of
restoration, whether that'strying to work with people in
power, in businesses or inpolitics or in powerful social
movements. So I think it's amixture of learning to deal with
(18:06):
work in tough circumstances,which is something that a lot of
people do, and also trying toalter the course of our work
such that it is moving towardspositive solutions, rather than
just describing depressingtrends.
Amy Martin (18:21):
After seeing too many reefs go ghostly white and
hearing them turn deadly quiet,Tim was determined to find ways
to help. He knew reefs wereincredibly dynamic, places that
can sometimes respond quickly topositive impacts, just like they
do to negative ones.
Dr. Tim Lamont (18:40):
The propensity these ecosystems have to change,
I find, is really amazing.
Amy Martin (18:46):
And he began to wonder if he could use sound to
help reefs ward off decline oreven come back from the dead.
Dr. Tim Lamont (18:55):
It's this idea that by playing the right
sounds, you can make placessound attractive to animals, and
they'll then, you know, altertheir behavior. You'll get
increased settlement, increasedimmigration, if you like.
Amy Martin (19:09):
We'll have more after this short break.
(19:31):
Hey, I want to take a minute tothank you for listening to
Threshold and to explain howimportant you are in getting the
show made. Most podcasts raisemoney by selling advertising,
and that pushes them to make alot of episodes as quickly as
possible. But that's just notwho we are. Our show is about
(19:52):
thinking deeply about how humansare fitting into the rest of the
web of life. We take you placesand craft stories that are
intellectually challenging andemotionally rich. That's the
kind of show we want to make,and that's the kind of show
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(20:15):
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easiest way of funding a show,but it is the way that's most
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campaign is happening nowthrough December 31 and each
(20:37):
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means if you can give $25 we'llreceive 50. You can make your
donation online atthresholdpodcast.org. Just click
the donate button and give whatyou can. And again, thank you so
much for listening.
Dallas Taylor (21:02):
I'm Dallas Taylor, host of 20,000 Hertz, a
podcast that reveals the untoldstories behind the sounds of our
world. We've uncovered theincredible intelligence of
talking parrots.
Unknown (21:14):
Basically, bird brain was a pejorative term, and here
I had this bird that was doingthe same types of tasks as the
primates.
Dallas Taylor (21:23):
We've investigated the bonding power
of music.
There's an intimacy there incommunicating through the medium
of music that can be really apowerful force for bringing
people together.
We've explored the subtlenuances of the human voice.
Unknown (21:38):
We have to remember that humans, over many hundreds
of thousands of years ofevolution have become extremely
attuned to the sounds of eachother's voices.
Dallas Taylor (21:46):
And we've revealed why a famous composer
wrote a piece made entirely ofsilence.
Unknown (21:51):
I think that's a really, potentially quite useful
and quite profound experience tohave.
Dallas Taylor (21:56):
Subscribe to 20,000 Hertz right here in your
podcast player. I'll meet youthere.
Amy Martin (22:02):
Hi Threshold listeners, do you ever find
yourself wondering whatbusinesses are doing and what
more they should do to confrontclimate change? Then you should
check out Climate Rising, theaward winning podcast from
Harvard Business School. ClimateRising gives you a behind the
scenes look at how top businessleaders are taking on the
challenge of climate change. Theshow covers cutting edge
(22:25):
solutions, from leveraging AIand carbon markets, to sharing
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(22:48):
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(23:16):
Welcome back to Threshold, I'mAmy Martin, and it's a November
night. The moon is just pastfull, and the corals are
spawning.
Dr. Tim Lamont (23:26):
It's this amazing night to be out in the
water, swimming around.
Amy Martin (23:31):
Marine Biologist Tim Lamont has an idea for how sound
could be used to help coral pushback against all the threats
they're facing, and tounderstand how it works, we have
to start here, during a spawningevent, when millions of tiny
corals release their eggs andsperm into the water.
Dr. Tim Lamont (23:49):
In many species, they all align, which is quite a
magical thing. So on one nightof the year, many of these
broadcast spawners will allrelease their gametes all at the
same time, and of course, thatmaximizes the chance that they
meet in the water.
Amy Martin (24:05):
Tim says, nobody knows for sure how the corals
manage to coordinate this way.They just know that it happens.
Dr. Tim Lamont (24:12):
You can see the tiny little egg bundles floating
up into the water, and you cansee the sperm being released
that creates such a buzz inactivity around the reef,
because there's so many otheranimals that then also come out
to feed on these eggs and thesperm and, you know, it's chaos
in the water. It's really loud,it's really busy. There's all
sorts of stuff swimming around.It's going in your ears, it's
going in your mask, it's goingdown your wetsuits. It's like,
(24:35):
yeah, busiest night on the reef.It's like, Saturday night, city
center, you know?
Amy Martin (24:45):
Amidst all of this ruckus, some of the eggs manage
to get fertilized and survive,and eventually a baby coral is
born, small as a grain of sand,bobbing around in the open
ocean.
Dr. Tim Lamont (25:00):
Then they come back to the reef, swept on ocean
currents, and settle. So thesefree swimming coral planulae, as
we call them, before they'vesettled, settle and become an
adult coral polyp. And that'show you create a coral reef with
millions and millions of thosecoral polyps.
Amy Martin (25:17):
It's called a biphasic life cycle. Birth and
early development spent out inthe open ocean, adulthood spent
on the reef.
Dr. Tim Lamont (25:26):
Corals have it in, other invertebrates have it,
even the fish have it. As an eggor as a very young juvenile
they'll be out at sea, and thenthere'll be this sort of journey
back to the reef when theorganism is ready to start its
adult life. Animals arrive carryon ocean currents and settle in
new places. Corals will settleand start to create habitat.
(25:49):
Different types of algae willsettle. Fishes will arrive, and
you can get a communitydeveloping based on new arrivals
from the open ocean, if youlike.
Amy Martin (26:02):
Creating a healthy reef is a cooperative process
with interdependencies radiatingout in all directions. The coral
structures provide great hidingplaces for fish that are trying
to hunt or avoid being hunted.The fish return the favor by
peeing and pooping on the reef,providing nutrients that are
(26:22):
crucial for the coral and thezooxanthellae inside of them.
The fish also eat some otherkinds of algae that would
otherwise smother the coral.They kind of mow the lawn,
clearing space for new coralpolyps to settle. So healthy
coral makes for healthier fishpopulations, which makes for
healthier algae, which makes forhealthier coral, and on and on,
(26:46):
the fates of all the plants andanimals here are tangled up
together. So that's whylistening to fish can help us
understand what's happening withcorals. Tim knew that sound was
a part of this communitybuilding process that young fish
listen out for the symphony ofpops, whoops and gurgles of a
(27:08):
thriving reef in deciding whereto settle. But he wanted to know
if that process could be hacked.When a reef was in decline,
could he intervene acousticallyand prevent it from going
silent? Finding out meantbecoming a reef DJ pumping out
tunes designed to get the partystarted.
Dr. Tim Lamont (27:30):
When we first tried this, I was doing my PhD,
so it was very low budgetscience. It was a lot of fun
putting it all together. So thefirst experiment we did, we had
these loudspeakers about thesize of a dinner plate. They're
sold as the loudspeakers thatyou would use to put in the
swimming pool for synchronizedswimming, so that the swimmers
can hear the music, right?
Amy Martin (27:50):
I just instantly saw all these fish in the line.
Dr. Tim Lamont (27:54):
It's all very little mermaid, isn't it?
Amy Martin (27:58):
These speakers were connected to little floating
barrels that held mp3 players.
Dr. Tim Lamont (28:03):
Which played one of our recordings of a really
healthy sounding reef out to theloudspeaker.
Amy Martin (28:08):
The next step was to tie the speakers to little
artificial patches of habitatmade by Tim and his team.
Dr. Tim Lamont (28:14):
Piles of rocks underwater, basically.
Amy Martin (28:16):
Then they pushed play and waited for someone to
show up.
Dr. Tim Lamont (28:20):
Repeatedly, repeatedly each day we go back
and visit these reefs and countthe number of fish that had
arrived, that had settled. Youknow, I'd go down with a
clipboard and and it was fun. Itwas like watching the
establishment of a tiny littlesettlement so underwater, yeah,
you know, you'd put your divegear on, roll off the boat and
go down and wonder, you know,who's moved in today? And we
(28:43):
found that on the reefs where wewere playing the healthy sounds,
twice as many fish would movein. The community developed at
twice the speed, and after 40days, that was twice the
abundance of fish.
Amy Martin (29:00):
In other words, it worked. Hearing the buzz of a
party made more fish want tocome in and hang out.
Dr. Tim Lamont (29:09):
So if we play the sound of a healthy
ecosystem, then that is a veryattractive sound, and that
literally calls in animalslooking for somewhere to live.
Amy Martin (29:20):
Tim's research gave us a new tool in the reef
restoration toolbox.
Dr. Tim Lamont (29:25):
What we have is a short term proof of concept
experiment. In that location, atthat time, we're able to double
fish abundance. There are a lotof other questions about whether
that would work in differentgeographical contexts, on
different reefs over longerperiods of time, over larger
spatial scales, and we don'tknow the answers to that yet.
(29:46):
There are exciting experimentsand studies going on around the
world to try and get thoseanswers, and time will tell what
the results of those experimentswill be.
Amy Martin (29:55):
But what about the animals at the base of all this,
the corals themselves? Is itpossible that they could be
encouraged to settle by playingthe sounds of a healthy reef? On
the face of it, this seemsimprobable. Corals have no ears
or even brains, but Tim haslearned not to make assumptions.
Dr. Tim Lamont (30:16):
Corals, especially in their little
larval stage, are constantlysurprising us with what they can
do.
Amy Martin (30:21):
And one of the intriguing things about the
coral planulae, those freefloating newborn corals, is that
they're covered in microscopichairs.
Dr. Tim Lamont (30:30):
And when you look at those hairs, they're
actually relatively similar instructure to the hairs that are
on the inside of our ears asmammals.
Amy Martin (30:38):
They're called cilia, and in humans, they play
an essential role in hearing.They grow deep inside the ear,
swaying and bending as soundwaves hit them and helping to
translate that mechanical energyinto chemical and electrical
signals that can be processed byour brains. And the cilia on the
(31:00):
bodies of baby corals seem tobehave in very similar ways.
Dr. Tim Lamont (31:05):
These hairs will vibrate in response to a passing
sound wave, and when we'vestudied these coral, planulae in
labs, people have discoveredthat they will change their
shape in response to the soundof a healthy reef. They'll
change their shape to one thatsinks in the water.
Amy Martin (31:23):
The research on this is still emerging, but it seems
that when the sound of a livelyreef is nearby, the planulae
will morph into a shape thathelps them sink down into the
water where they're more likelyto find a good place to call
home.
Dr. Tim Lamont (31:39):
If you put them in a tube, and you play the
sound of a healthy reef from oneend of that tube, they'll even
start to swim down that tubetowards the loudspeaker.
Amy Martin (31:48):
These tiny infant corals are somehow queuing into
the hubbub of a reef. It's liketheir bodies become ears bobbing
along in the ocean. Half abillion years ago, long before
anything was calling or cryingor singing, these little beings
(32:09):
may have been learning tolisten.
So just to be clear about whatwe know and what we have yet to
find out here, we know that babycorals definitely respond to
reef sounds in the lab andinside containers anchored to
(32:31):
the sea floor. Whether or notthose planulae are using sound
to find and settle on reefs whenthey're swimming freely in the
wilds of the ocean is still anopen question. But again, Tim
has learned that these ancientcreatures shouldn't be
underestimated.
Unknown (32:49):
So there's some really quite amazing abilities of
these, you know, animals thatinitially appear to be very
simple, but are able to respondto these complex acoustic cues
in their environments aroundthem.
Amy Martin (33:02):
New research on coral reef acoustics is coming
out all the time, but so are newreports of dying reefs. We need
legions of scientists like Tim,people who are willing to commit
their lives to finding outeverything we can about coral
reefs and acting on thatknowledge as quickly as
possible, but scientists canonly do so much. We're in a race
(33:26):
against time, or moreaccurately, against ourselves.
You are nurturing this extremelyimportant habitat in this
absolute time of crisis. Maybeif we can get some version of
them through the next 30, 60,150 years, then maybe there's a
(33:49):
chance for them to get throughthis bottleneck. And do you see
yourself that way, as like acoral shepherd moving them
through a bottleneck?
Dr. Tim Lamont (33:56):
That I guess, is where, where this comes to roost
is a story that involveseverybody. The local efforts
that we have can only reallywork within the parameters of
the direction of global change.And you know, the climate story
will be one that writes thenarrative in the long term for
(34:17):
all of this.
Amy Martin (34:28):
So we need all of these efforts all at once.
Hands-on, long-term,science-driven restoration
projects adapted to the specificneeds of different ecosystems.
But those things won't be enoughon their own. We also have to
decide as a global community ifwe want to keep burning fossil
(34:50):
fuels or if we want to havecoral reefs, because we can't
have both.
Dr. Tim Lamont (34:58):
Reefs are valuable. Even outside of what
they provide to humanity,they're fantastically beautiful,
diverse and unique livingstructures. I think it would be
a terrible, terrible indictmentof humanity if we didn't do
everything in our power toprotect them.
Amy Martin (35:27):
Corals are survivors. For hundreds of
millions of years, they've beena keystone species, creators of
vital habitat that helped ourplanet transition from desolate
silence to cacophonous life. Butthis wild flourishing didn't
have to happen, and there's noguarantee that it will continue.
(35:53):
Life on Earth is resilient, butit's not inevitable, and it's
not indestructible.
(36:28):
This episode of Threshold waswritten, reported and produced
by me, Amy Martin, with helpfrom Erika Janik and Sam Moore.
Music by Todd Sickafoose. Postproduction by Alan Douches, fact
checking by Sam Moore. Thesounds of coral reefs and the
fish you heard in this episodewere generously provided by Tim
(36:49):
Lamont and the followingscientists, Ben Williams, Emma
Weschke, Eric Parmentier, IslaKeesje Davidson and Steve
Simpson. Big thanks to all ofthem. This show is made by
Auricle Productions, a nonprofitorganization powered by listener
donations. Deneen eiske is ourexecutive director. You can find
(37:11):
out more about our show atthresholdpodcast.org.
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