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  • Here, off Canada's Pacific coast, researchers are

  • hoping to make a long-held dream come true.

  • Behavioral biologists and IT experts have teamed up

  • to create programs aimed at deciphering

  • acoustic signals from animals.

  • Could artificial intelligence help to identify

  • patterns in the sounds made by marine mammals?

  • Will we soon start to understand

  • what it is that whales are talking about?

  • The coastal waters between Alaska in the U.S.

  • and Canada's Vancouver Island are where a group

  • of killer whales ororcasspend their summers.

  • A team of scientists from the DEEP AL research expedition

  • are preparing to embark. “DEEP ALstands for

  • Deep Learning Applied to Animal Linguistics.”

  • Computer scientist Elmarth from Germany's

  • University of Erlangen has spent years working on

  • automatic recognition for human speech patterns.

  • Can the same methods be adapted to animal languages?

  • Underwater microphones embedded in

  • tubes serve as the expedition's ears.

  • For three summers, teams of computer scientists

  • and biologists have set out to record orca calls

  • and document whale behavior.

  • Rachael Cheng from the Leibniz Institute for

  • Zoo and Wildlife Research in Berlin is looking for

  • patterns between behavior and animal vocalizations

  • that could help to decipher whale language.

  • I assume they would exchange information.

  • They may have a very, very different system which

  • may not fit into our prototype of a language.

  • Around 300 orcas are identified as "Northern Residents"

  • as they spend each summer along the coast

  • of Alaska and northern British Columbia.

  • They live in small family groups and are very communicative.

  • Do different families use different dialects?

  • And is it possible to discern the meaning of individual calls?

  • Here the researchers lower the

  • highly sensitive microphones into the water.

  • The eight hydrophones can record sounds

  • up to a frequency of 100 kilohertz.

  • That's far higher pitched than what is audible to the human ear.

  • Thanks to the network of hydrophones and acoustic triangulation,

  • the researchers will later be able to

  • calculate the positions of the whales.

  • To avoid disturbing the whales with engine noise,

  • the research trimaran is equipped with an electric motor.

  • While visibility is usually limited underwater,

  • sound waves are transmitted over considerable distances.

  • That's why a communication system

  • with loud calls is clearly beneficial.

  • They're very tight together, with frequent direction change.

  • Circling. And body twisting. Plus a lot of echolocation.

  • They are socializing, like you will see.

  • They bump into each other and rub, and frequent twisting,

  • and then jump onto each other.

  • It sounds like they talk about the plan

  • What are we going to do next?”

  • Orcas only spend about five percent of their time at the surface,

  • which makes systematic observation quite difficult.

  • The research team uses drones to

  • document the behavior of the animals.

  • Diving expeditions with whales are prohibited in Canada.

  • The scientists are looking for the

  • smallest meaningful units of communication.

  • Which whale is calling, and which one answers?

  • Are some sounds repeated more than others?

  • Biologist Elysanne Durand examines the recordings.

  • Each call comprises a series of brief pulses which

  • sound like melodic curves to human ears.

  • Each shift in sound could be meaningful.

  • While recording the whale calls, the researchers also

  • document the behavior of the animals.

  • So there's four individuals in this group here that are circling,

  • there were four back there with the male,

  • there is one I can see out of the corner of my eye coming towards us,

  • and the mom and calf.

  • So that's 8, 10, 11 individuals minimum.

  • The more data available, the easier it is to "train"

  • deep-learning programs to decipher whale language.

  • It's therefore a major advantage for the researchers that over

  • 20,000 hours of orca calls have already been collected

  • more than for any other animal species.

  • Whale researcher Jared Towers has been tasked by the

  • Canadian government with observing different orca populations.

  • Back in the 1970s, scientists here began documenting

  • individual animals as well as their group structures.

  • A108 is right underneath the boat here,

  • here she is, she is gone off ahead.

  • Jared Towers has no problem telling the orcas apart.

  • This scratch here on A108 has persisted

  • for at least a couple of years now.

  • So the way that we identify the individuals no matter what

  • population they belong to is by appearance and

  • you get used to looking for certain features

  • on an individual killer whale.

  • The dorsal fins and the patches around

  • the fins have different shapes

  • enabling scientists to catalog each of the Northern Residents.

  • Every family forms a lifelong bond.

  • What we are looking at with all these families

  • is an adult female leading the group,

  • and the fathers of their offspring don't play

  • much of a role in that family group.

  • Jared Towers works for a federal institution

  • that safeguards Canada's waters.

  • His former boss, John Ford,

  • was the first to distinguish between the disparate calls of the whales.

  • Ford's research revolutionized our understanding of the

  • communication system used by the resident orcas.

  • We are listening to calls of A-Clan whales.

  • That is the exciting part of underwater listening.

  • You are getting a window into their life that you would never see.

  • John Ford discovered that the whales use about 50 different calls.

  • Different families prefer different types of calls.

  • These were nameddialects

  • and used to help identify individual families.

  • When they are making the various stereotyped signals,

  • it's simply to keep in touch with everybody in the group

  • they exchange them, they are constantly

  • monitoring each other's location.

  • They know where they are because of their very directional hearing,

  • and they can monitor the behavioral state, the excitement level,

  • the arousal state of all the other animals in the kin group.

  • Northern Resident orcas visit pebble beaches daily.

  • You can hear them rubbing right now.

  • They're making socializing sounds and you can hear

  • the pebbles getting pushed around.

  • And they just rub all sides of their body.

  • Just in the shallow part of the beach.

  • Only a few orca groups worldwide engage in this sort of body rub.

  • This behavior is not genetic, rather it's a tradition passed on

  • within families of the Northern Residents, just like their language.

  • Back on the German-Canadian research boat,

  • it's a challenge to locate each family among the 300 individuals

  • that make up the Northern Resident population.

  • The orcas are constantly on the move in an

  • expanse of water the size of Belgium.

  • The expedition covers an area from

  • Vancouver Island to the southern tip of Alaska.

  • Seagulls indicate where schools of salmon might be.

  • And this is where orcas often hunt too.

  • Calls from the “A-Clancan be heard on the underwater microphones.

  • The team tries to determine the position of the whales.

  • They compare the calls with the catalog compiled by John Ford,

  • but they encounter discrepancies.

  • The calls of class "N9" are used by different whale families.

  • Calls from the same class should be almost identical,

  • but these differ in length, melody and harmonics.

  • Human analysis so far has amounted to only a rough classification.

  • Looking at the spectrogram I am very sure that we can

  • achieve something that rivals the human performance.

  • Two whale families approach. What calls are they exchanging?

  • Here is that call. OK, let's just record this.

  • After I hear the call the back group surfaced.

  • Then I spotted the front group turning around.

  • The researchers are interested in which group is calling,

  • which one answers, and which sounds they're using.

  • Look here, I4 is approaching the boat. You can hear lots of calls.

  • That's N23 from the GI clan.

  • There is a lot of variation also

  • and interestingly, here is the A23 family.

  • The calls look very different.

  • That's how people differentiate different matrilines.

  • If we have a lot of calls, we can try to train a classifier.

  • The programmers use algorithms orclassifiers

  • to automatically analyze millions of whale calls in order to

  • compare recurring sound patterns with recurring behavioral patterns.

  • This same method is used to decipher the meaning of

  • individual words in foreign languages.

  • For Elmarth and his team, it's no easy feat to automatically filter

  • out the weak orca calls from the constantly

  • fluctuating noise of the ocean.

  • By matching thousands of orca calls on the input side with a

  • target value on the output side, they trainneural networks.”

  • These layers of neural networks then learn bit by bit

  • which sounds are typical for orcas.

  • The purple peaks indicate a high

  • probability of having found a whale call.

  • It's the first time a machine has been trained to

  • automatically detect orca sounds.

  • Still, clustering calls into similar

  • sound groups remains a big challenge.

  • When comparing tens of thousands of recordings,

  • all whale calls are sorted by what they have in common.

  • But the cluster is still too crude to form reliable classes.

  • Further programming is required.

  • The team suspects that the Northern Resident orcas have a

  • complex language system and may even process more

  • intricate sound patterns than humans.

  • But how much is even known about the acoustic capacity of their brains?

  • This is Telegraph Cove on Vancouver Island,

  • where Elmarth and Rachael Cheng have an appointment.

  • Only a handful of researchers worldwide have

  • expertise on whale and dolphin brains.

  • Neuroscientist Lori Marino is one of them.

  • Is this an orca brain?

  • This is an orca skull, a cranium and in the front you find the melon,

  • where they do the echolocation.

  • And this part right here, this large part, is where the brain would sit.

  • Human and whale brains generally share

  • the same mammalian architecture.

  • Both cerebral cortices are wrinkled and complex.

  • But the orca brain is 5 times bigger,

  • among the largest of any animal.

  • And unlike the human brain, the orca also has a paralimbic lobe.

  • The part of the orca brain that mostly

  • fascinates me is this part right here.

  • We have this special extra lobe, called paralimbic lobe.

  • It connects feelings, emotions and thoughts.

  • And it's so complex in the orca brain, it has become its own lobe.

  • That means a lot more of their communication has to

  • do with their feelings and emotion?

  • Communicating feelings, communicating emotions,

  • is very important to an orca.

  • Whales have a far larger acoustic area than humans.

  • Lori Marino's team also discovered a second acoustic cortex.

  • And now we know that they have also a sound processing

  • area in the same area where we process language.

  • Based on what you said how they process sound,

  • can we say that we need a much finer window when we analyze?

  • It's not just fine resolution that we need.

  • We need a way to do the analysis at a much more

  • complex level than our brains can do it.

  • New brain scan methods have revealed that orcas have a

  • far more complex acoustic system than previously believed.

  • Could the same be true for other marine mammals

  • that use sound for their communication and orientation?

  • In contrast to other orca groups,

  • the Northern Residents at some point stopped hunting

  • seals and other marine mammals.

  • Today they feed almost exclusively on the largest salmon in

  • Canadian waters, the Chinook.

  • Stocks of the fish, however,

  • have been declining rapidly since the late 1990s.

  • The Northern Residents have to travel increasingly long

  • distances to find the salmon that still remains.

  • And despite stringent fishing quotas for the species,

  • their numbers continue to decrease.

  • Jared Towers from Fisheries and Oceans Canada monitors if

  • people are complying with the fishing regulations.

  • It seemed to be that if Chinook salmon

  • aren't quite so much abundant,

  • the killer whales aren't getting enough to eat and that

  • causes populations to go down a little bit.

  • The Northern Resident Orcas are

  • classified as a "threatened species.”

  • When Chinook abundance is low,

  • they don't simply go and try catching other fish.

  • They have not found an alterior prey resource.

  • It is not like they start and go kill harbor seals,

  • just when there is not enough salmon around.

  • The substantial human appetite for salmon has

  • decimated stocks to critically low levels.

  • The ruins of the salmon fishing industry serve as a reminder

  • of the once abundant fish stocks.

  • Wild Canadian salmon were in great demand around the world.

  • The survival of the Northern Resident orcas is tightly linked

  • to the fate of the Chinook salmon.

  • Lance Barrett-Lennard is a geneticist and

  • behavioral ecologist at the Vancouver Aquarium.

  • He visits the resident orcas every summer to document their

  • long-term health and measure how their body size and

  • shape compares to previous years.

  • To ensure the images are comparable from year to year,

  • the drone hovers exactly 30 meters above the whales.

  • The group's calf is almost a year old

  • and is still suckling from its mother.

  • The social skills of orcas are illustrated

  • by how they deal with their prey.

  • You've got a species that is highly social, that shares all of its food.

  • So they're compulsive sharers, killer whales.

  • When they catch a fish, one will eat half and head it off to

  • somebody else and have a bite, and then another one takes a bite.

  • The adults sometimes leave living salmon to the younger whales.

  • In this way, the juveniles learn to hunt their prey in a playful way.

  • At the Vancouver Aquarium,

  • researchers compare the images from different years.

  • One indicator of the whales' state of health are

  • the white patches above their eyes.

  • If there are not enough fat reserves in the neck area,

  • the angle along the eye-spots will change.

  • Comparing the images side by side,

  • researchers observe a life-threatening weight loss.

  • In response to the decline of natural stocks,

  • the fishing industry installed aqua-farms in the regions the

  • remaining wild salmon migrate through.

  • Nets protect the farmed salmon from orcas and other predators.

  • The predominantly Norwegian operators introduced

  • farmed Atlantic salmon species

  • and with them, new viral diseases not

  • previously found in Canada's Pacific Northwest.

  • These fish farms raise as much salmon

  • as possible in a confined space.

  • It's all about maximizing profit.

  • The by-product? Feces and germs that escape into open waters.

  • There is growing concern of viral

  • outbreaks among the wild Chinook salmon.

  • If the primary food source of the resident

  • orca population continues to decline,

  • the whales' own survival will also be endangered.

  • Whale researcher Alexandra Morton is studying the

  • new diseases affecting the salmon.

  • She visits the research trimaran to share the results of her analysis.

  • I brought some results on my laptop,

  • if you'd like to see them, the virus research

  • where we found it and why are the salmon farms such a

  • big problem for the salmon and the whales.

  • Mostly because of where they are located.

  • So we do a molecular test that basically just looks for the

  • genetic sequence or part of the sequence of the virus.

  • Salmon take in viruses through their gills.

  • The pathogens then infect their bloodstream, causing organ failure.

  • When the salmon farms moved in, the orca stayed away.

  • That made Alexandra Morton suspicious.

  • She took samples near the farms,

  • which were then analyzed in special laboratories.

  • She examined the organs of both wild and farmed salmon.

  • 95 percent of the farmed fish she dissected were sick.

  • A large proportion of the wild salmon also became

  • infected through contaminated water.

  • The pathogens escape from the fish farms with the

  • tidal currents and spread to the regions the young

  • wild salmon have to pass through as they migrate.

  • 200 kilometers further north, the “A42” family

  • searches for prey along the shorelines.

  • The research expedition has reached the fjords of Fisher Channel,

  • once famous for its ample fishing grounds.

  • The whales hunt by day and by night.

  • They don't need light for orientation.

  • Biologist Florence Sullivan compares her recordings to

  • known call types and notes down behavior.

  • Do the orcas tend to use certain calls in

  • a social context, or more when hunting?

  • All recordings are later re-analyzed in Germany

  • with the help of "deep learning" programs.

  • In their search for prey, the Northern Resident orcas now

  • often cover 80 to 120 kilometers a day

  • along hunting routes that have been passed on for generations.

  • To identify individual whales and examine changes in group structures,

  • programmer Manuel Schmitt and biologist James Field are working on

  • automatic "fin recognition software.”

  • It works similarly to facial recognition programs.

  • The process of identifying whales by their fins and dialect was used

  • years ago in the famous case of an

  • orphaned calf known as "A73” orSpringer.”

  • When her mother died, the then 2-year-old Springer was

  • separated from the rest of her family.

  • Eventually, 300 miles further south,

  • the lone calf was found off the coast of Seattle.

  • Scientists could tell from her calls that she was a “Northern Resident.”

  • Springer was brought back and reunited with her family.

  • So while researchers have been able to

  • identify whale dialects for 20 years now,

  • understanding thelanguage of whales

  • represents a whole new challenge.

  • The call systems used by different whale families change

  • little from one generation to the next.

  • Springer now has two calves of her own,

  • "Spirit" and "Storm" — roughly eight and four years old.

  • Orcas typically spend their entire lives with their mothers.

  • For the first two years they are suckled

  • and over the following eight years,

  • they learn what they need to do to survive.

  • Another orca group has joined Springer's family.

  • Together they search for salmon close to the shore.

  • Their hunting strategies vary depending on the local environment.

  • This gives them a wealth of experience that,

  • like their communication system, is passed down through generations.

  • Their group behavior during the hunt seems to be coordinated.

  • The whales exchange a stream of calls.

  • The orcas are still able to find enough food by

  • spending more and more time hunting.

  • For a calf, it's one of many lessons in salmon hunting.

  • For the scientists, it's a rich source of data.

  • Human activity greatly impacts the whales' habitat.

  • This continuous loud sound...

  • and now the orca calls become the background.

  • The sound of passing ships doesn't frighten the whales...

  • but the noise does interfere with their communication

  • and compromises their hunting ability.

  • The Canadian government is investigating the impact of

  • ship noise on marine mammals.

  • We listen for their vocalizations,

  • which can cover a range of 10 km or so.

  • Man-made noise in the world's oceans doubles every ten years.

  • One of the concerns we have about vessel noise is its

  • potential impact on the

  • echo-location abilities of the whales.

  • The whales' vision is very limited underwater,

  • because of murkiness in the water, especially at night.

  • Typically in these waters they can't see more than a whale's length,

  • perhaps 10 meters max.

  • In quiet conditions the whales can probably detect a

  • Chinook salmon at a range of perhaps 200 meters,

  • but that might be significantly reduced by masking, by boat noise.

  • Similar to bats, orcas scan their surroundings by emitting

  • clicking sounds and listening to their echoes.

  • The noise from ships masks those echoes.

  • To reduce its own engine noise,

  • the expedition boat runs on an ultra-quiet electric drive.

  • It sounds like a N4 call.

  • But it's masked in the noise.

  • Here we have the boat's engine noise.

  • And there is an orca call here.

  • I have another recording with our engine

  • You can hear the harmonics. It's much clearer.

  • Still we have this electrical noise at 10 kHz.

  • Let me have a look at the engine.

  • Although electric engines are far quieter,

  • there's nevertheless some interference.

  • Rachael Cheng inspects the static noise

  • and examines the control cables.

  • Is it better now?

  • Much better now.

  • The sound of electric motors is still rare in the ocean

  • which is perhaps why the ship triggers the whales' interest.

  • The boat stops in order to maintain the

  • requisite distance of 100 meters.

  • The curious orcas are not quite as cautious

  • and inspect the boat and its crew.

  • The scientists wonder whether the whales might

  • use distinct calls for different boats.

  • In any case, there is immense curiosity on both sides.

  • Orcas are extremely social creaturesand love to touch one another.

  • I think this is the A23 and A25 group. Floating sideways.

  • Putting its fin on the water surface

  • where others just mingle around.

  • Are their jumps also part of their communication?

  • Or just a bit of fun?

  • Many of their behavioral patterns are

  • still only partially understood.

  • This is also due to the fact that orcas

  • rarely roam close to the surface,

  • where humans can observe them.

  • Some distance away, another group of orcas suddenly appears.

  • Marine biologist Elysanne Durand wants to get an overview.

  • Which direction should I go now?

  • If we can have the whole group on our starboard side ...

  • This is a completely different type of orca.

  • There are maybe 4 transients off the island.

  • Unlike the resident whales,

  • these transient orcas don't feed on salmon.

  • They hunt other marine mammals.

  • Do you hear anything from these guys, Rachael?

  • No, I don't hear any vocalization.

  • But it seems they're hunting there, foraging.

  • In another contrast to Northern Residents,

  • transient whales hunt almost silently.

  • This is because dolphins, seals and other whales

  • their natural preyhave excellent hearing.

  • That means, they know exactly when they're in danger.

  • The transient orcas also inspect a rocky plateau for prey.

  • ? a tactic that appears to be successful.

  • We hear them vocalize now.

  • The blood at the surface reveals a kill.

  • The transients begin to celebrate their catch

  • and now exchange many calls back and forth.

  • Acoustically they are very different from the residents.

  • I'm curious whether the classifier can pick up the difference.

  • The homes of the roughly 500 transients

  • and 300 Northern Residents overlap.

  • But their calls differ so much, it's as

  • if they're speaking different languages.

  • Dolphins and other marine mammals can tell the difference.

  • While they immediately flee from transient whales,

  • they rush intentionally toward the residents

  • as soon as they hear their calls,

  • to hunt and play with them.

  • Below deck, Elmar Noeth and Christian Bergler work on

  • the automatic call classification.

  • Here, hear the orcas? It shows here the detection of those signals.

  • We always have 2 seconds, 2 seconds, 2 seconds.

  • You can clearly see the incoming sound.

  • If there is an orca, they will be detected.

  • What I like is that the confidence is so high.

  • The algorithm is quite sure that it did find.

  • The automatic call detection works?

  • But the challenge is still to match one groups of calls with another.

  • In human language, the equivalent of these sound sequences

  • might be simple statements.

  • The Northern Residents consist of 32 families.

  • They typically use different call systems

  • but are still able to communicate with each other when they meet up.

  • Looks like the other group is joining them.

  • The calls between the groups go back and forth

  • announcing their arrival in a kind of greeting ceremony.

  • Do you still think they are saying, I am here, if they are so close by?

  • No, it's not the same call.

  • The last time it was really one call the

  • individual was repeating all the time.

  • Here they are doing combinations.

  • Meetings between family groups used to be more frequent

  • when salmon stocks were more abundant, and they had to hunt less.

  • It seems to be more melodic.

  • Their sounds or vocalizations were a lot longer.

  • I would say they are more complex.

  • They exchange another series of calls

  • before the meeting slowly breaks up.

  • These sounds might signify "goodbye.”

  • But the researchers will need to compare many other similar exchanges

  • before they can interpret it more decisively.

  • There are thick banks of fog between Vancouver Island and

  • the mainland as the end of summer approaches.

  • Tracking down the whales is more of a challenge.

  • The researchers' only option is to use

  • acoustic localization with the hydrophones.

  • Under calm sea conditions the sound of the orca calls

  • can range up to 10 kilometers.

  • Elmarth checks the location forecasts.

  • At 12 o'clock, 200-300 meters?

  • Over there at 1 o'clock — 1, 2, 3, 4.

  • Localization is also important in order to interpret the calls.

  • It's like 2 or 3 here, 2 or 3 there

  • and then it's always the same call we hear right now.

  • So it's probably, "I'm here.”

  • And the other one recognizes, "oh, Fred is over there.”

  • What I would do is to cluster exactly those calls where

  • I'm convinced that I heard the same.

  • And then just from the sequence one could make the assumption

  • that's a signal-and-response signal, something like that.

  • The last of the three expeditions is coming to an end

  • with data from a total of 20 weeks of field research on board.

  • A few months later, the researchers meet at the

  • Pattern Recognition Lab at the University of Erlangen

  • in Nuremberg, Germany.

  • Rachael Cheng has an appointment with the programming team.

  • Manuel Schmitt has run an automatic comparison of one million calls.

  • Hi Rachael, good that you're here.

  • Take a look at the clustering. I made some changes.

  • It's a little bit better than before.

  • N3 is here, it looks very similar, but its mixed with N9s over here.

  • This one looks very different but it still needs training.

  • Background noises hinder the automatic sorting of various calls.

  • A newly programmed noise filter increases the precision.

  • Is that the new clustering? That's a lot better, right?

  • It makes tiny differences.

  • There are tiny artefacts.

  • There are still small errors. But on such a large scale

  • where millions of calls are being automatically compared

  • these become less significant.

  • I think we're now at the level where we can run

  • through a couple of tapes now.

  • But you can use those cluster sequences in order to find

  • those language patterns - like a semantic structure?

  • And those can be interpreted as a call,

  • followed by an answer-call, followed by another call.

  • The new clustering results are better than expected.

  • Rachael Cheng's task now is to assign

  • recurring call patterns to certain behaviors.

  • She compares the new clusters with the existing call-catalogs

  • and discovers reappearing matches that might be meaningful.

  • The algorithms have learned to

  • differentiate the calls of different orca families.

  • That would normally take human researchers years of training.

  • In the future, this will allow automatic

  • detection of which family is calling,

  • and the ability to follow the

  • subsequent dialogues between families.

  • The next step is comparing millions of call sequences.

  • Which calls appear together frequently,

  • accompanied by which similar behavior?

  • When decoding human languages,

  • such connections might reveal meaningful possibilities such as

  • sitandchairortableand plate.”

  • The deep-learning programs cannot yet work completely independently.

  • Without human control, there could be

  • a huge increase in assignment errors.

  • The first matches appear

  • The same call sequences were used in a similar context.

  • But there are exceptions.

  • The comparisons made so far are not conclusive.

  • The re-occurring call sequences point

  • to the scenethey are socializing.

  • And we also find it the second time in a

  • socializing context, the same call patterns.

  • We expect to find it in the third sample

  • also, but we did not find it in this.

  • That does not disprove it. There could be different explanations.

  • We just don't have enough data to say that.

  • The German-Canadian research team is not yet able to create

  • a kind of dictionary of the orca language.

  • But they do now have tools to compare whale calls in a more

  • detailed and systematic way than was previously possible.

  • And as more recordings of whale calls are shared and

  • made available for training deep-learning machines,

  • the faster it will be to recognize the

  • subtleties in communication patterns.

  • Humans have long faced limitations when

  • it comes to understanding what animals might be talking about.

  • But with the help of AI, a new era of research might allow us to

  • decipher the secrets behind their communication.

Here, off Canada's Pacific coast, researchers are

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