
Gresham College Lectures
Gresham College Lectures
Exploring the Deep Sea
The Deep Sea is Earth’s last great frontier. After almost 150 years of exploration and research we understand it is deep, dark and definitely different; but there remain large gaps in our knowledge that hinder progress in sustainable management of this vast system. New technology – from manned submersibles, to satellite measurements, acoustic systems, and artificial intelligence – is key to future research, and the next ten years promises to deliver a new age of deep-sea science.
A lecture by Kerry Howell
The transcript and downloadable versions of the lecture are available from the Gresham College website:
https://www.gresham.ac.uk/lectures-and-events/deep-sea
Gresham College has been giving free public lectures since 1597. This tradition continues today with all of our five or so public lectures a week being made available for free download from our website. There are currently over 2,000 lectures free to access or download from the website.
Website: http://www.gresham.ac.uk
Twitter: http://twitter.com/GreshamCollege
Facebook: https://www.facebook.com/greshamcollege
Instagram: http://www.instagram.com/greshamcollege
- I'm going to spend the next 50 minutes or so, introducing you to, what is most of our planet, and in particular, I'm going to talk to you about how, our knowledge of this environment has very much been shaped by the technology that's been available to us, to study this area. So, just to give you a bit of an overview of what I'm going to talk about, I'm going to talk about initially, the history of deep sea biology and the Challenger expedition, which really kick started the whole science of deep sea biology and also oceanography. And then I'm going to move on to talk to you about, how camera technology has really been a game changer in terms of our understanding of this whole biome. Then I'm going to talk to you a little bit about, habitat mapping and sea floor mapping and how the map that you see of the seabed, that you see when you go on Google Earth. It's not really a map at all. It's more of a model of what we think the seabed looks like. And then finally, I'm going to talk about how new technology is set to really revolutionize, our ability to study the deep sea environment. And we're going to see some incredible things, over the next 10 years or so. But to begin at the beginning, and I hope this is not news to anyone, that about 75% of our planet is covered in ocean. We are in fact, planet ocean rather than planet Earth. And if you spin the world round and take a view of the world from this angle, which shows the Pacific, I think it's really easy to see that we are in fact planet ocean. And actually the average depth of the ocean, is a little bit over 3000 meters. And so in fact, we are planet deep sea, it is most of our planet. But what is the deep sea? So, when you say deep sea to the lay public, most people just think it's sort of deep water and you're not wrong, it is. But in biological terms, the deep sea has a very specific meaning and it refers to the area that is beyond the continental shelf. So, if you look at the map we have here, you can see the UK island, Europe and you can just see Norway and Sweden at the top there. There is this very flat blue, light blue area that surrounds the UK and that's what we call the continental shelf. And that's where most of our fishing activities go on, oil and gas, human uses of the marine environment, really dominate on the shelf. But if you look, the shelf very clearly ends, west of the UK and Ireland, and then it slopes a little bit more steeply down onto the abyssal plain, which is the very dark blue areas, you can see there. The abyssal plain are these flat areas of the seabed, very deep, four to five kilometers deep, and they take up quite a large part of the deep sea. So, the deep sea really, is the area from the edge of the continental shelf, where it breaks, that sloping area and then out onto the abyssal plains, And around the UK and Ireland, the depth at which that occurs is about 200 meters, but it's different in different parts of the world. So when we say deep sea, we are generally talking about the area deeper than 200 meters and off the continental shelf. So, I said, I was going to talk to you about the history of deep sea and Challenger. And when you say Challenger to people, most people think of this, The Space Shuttle Challenger, and they don't realize that the Space Shuttle Challenger, was actually named after the original Challenger and the original Challenger was a ship, a Naval vessel, HMS Challenger. And HMS Challenger set sail about 150 years ago. In fact, exactly 150 years ago, this December, set sail from Portsmouth on a four year expedition around the world to learn about the deep sea environment. Now, at the time most people thought and it was widely believed that the deep sea was azoic, it had no life in it. And it came from a chap called Forbes and Forbes' Azoic Theory. And Forbes was a natural historian at the time, a scientist, but he had been studying the Aegean Sea and sampling down the depth gradient in the Aegean Sea in the Mediterranean. And what he had ever observed is that, animal life seemed to decrease with depth. It became not very diverse and there was much less of it. And so he calculated that below about 500 meters, in fact, there would be no life at all, based on his observations. And despite actually evidence to the contrary, before Forbes came up with this theory and evidence that continued to grow, after Forbes came up with this theory, people accepted it. And, you can kind of understand why, and I'll explain a bit more about the deep sea in a moment, but it is sort of an inhospitable environment. It would be easy to see why people might think, there was no life there. Unfortunately, the Aegean is sort of unusual in deep sea terms, but Forbes couldn't have known that, but it does rather highlight the problems of extrapolating your data beyond the area that you've studied. But it was the Challenger expedition that really put the final nail in the coffin of Forbes' Azoic Theory and demonstrated without a doubt that there was life in the deep sea, the whole world over. So the Challenger expedition spent four years, going around the world. It took over 400 depth soundings on its journey. It visited over 300 stations to sample the biology and around 150 or so of those stations were dredge stations. So actually, trawling on the seabed. And through all of this activity it discovered well over 4,000 new species and all of its findings were published in around 50 volumes that took more than 20 years to write. It was an incredible undertaking. You can see the route of the Challenger here. It went through most of the world's oceans, but it didn't go into the Arctic or the Antarctic. And they remained unstudied at that time. Now, the Challenger expedition didn't set out to do deep sea science. It wasn't out there to discover species or anything along those lines. The actual reason behind the expedition was, the advent of telecommunications and the telegraph. So, the UK wanted to lay cables on the seabed to connect the UK up to North America and laying these telegraph cables. And they realized that they would have to know something about the shape of the sea floor in order to know where to lay the cables. And so, all these depth soundings, and they also took the temperature of the ocean, were very important to informing the laying of cables. And that's really what funded the expedition, not biology, unfortunately. But it's incredible to think that, from all of those depth soundings conducted by Challenger. And of course the previous expeditions that had gone before that and the soundings they had made, they were able to construct this map of the sea floor. So, it was the Challenger who discovered, the very deepest parts of our ocean, the great ocean trenches in particular, the Marina Trench, the deepest part of which is called the Challenger Deep, after the Challenger. But the Challenger expedition also discovered the Mid-Atlantic Ridge, which is this light area that runs all the way down the Atlantic. It's like the spine of the Atlantic. It's a great mountain range underwater. And we had no clue it was there, until the Challenger basically picked it up and followed it all the way down the Atlantic on part of their expedition, to try and map how far it went. So, this was our map of the sea floor that came from that expedition. Now, in terms of the biology, I mentioned dredging, and the Challenger was using a dredge. You can just see in the background here, the dredge hanging up, ready to be deployed. And that was lowered down to the seabed, dragged along the bottom, brought up to the surface and the animal life within it examined and described. And interestingly as well, I should have mentioned that the way in which they were sounding the seabed, and you may know this is by lowering rope to the sea floor with a weight on the end of it. And you'd know the depth of the water by the amount of rope that was let out. And if you think the Marianna Trench is 11 kilometers deep,(chuckles) that's a lot of rope. Luckily they had a donkey engine, which you can just see in this image to haul the rope back up, again, it wasn't hand hauled. But these trawls that you can see there were the really important part of the expedition. And in fact, trawls and dredges have been the mainstay of deep sea biology ever since. So, you can see the trawl in the original image from Challenger here. This is a photograph from a fairly recent expedition, by the British Antarctica Survey down to Antarctica. And you can see the dredge there, it's a slightly different make of dredge, but beyond that, it's pretty much the same as it's always been. So, we've been using trawls and dredges as a means to explore the deep sea you for the last 150 years. And trawls and dredges are really useful because they return physical specimens that you can look at, you can describe, and you can dissect and learn something about the biology of the animals from looking at their physical form. And it's taught us so lot. We know quite a lot about the deep sea from dredges and trawls and also physical oceanographic measurements, and also those depth soundings. So, what do we know about the deep sea environment? Well, the first thing to note about it, is that light decreases with depth. It's pretty obvious, as you go down through the water column, the amount of light available becomes less and less. And by about 200 meters, there's not enough light for photosynthesis anymore. So, plants and algal life cannot live or photosynthesize below 200 meters. It varies in, throughout the world's oceans, but on average, it's about 200 meters. By the time you get down to a thousand meters, there's no light at all, no sunlight. The only light comes from, light that is made by animals themselves in the form of bioluminescence. So, it's dark below a thousand meters. The other thing that happens is, temperature decreases with depth. So, at the surface, around the UK, this time of year, it's going to be about 15 degrees or so, as you go down the water column, it gets colder and colder. And by about a thousand meters, it's only about four degrees C, and that's about the temperature of your fridge. So, it's pretty chilly. And then by about 4,000 meters, four kilometers on the abyssal plains, it's about one degree C. So, very chilly. And then the final thing is pressure. So, we live in one atmosphere of pressure. We've got an atmosphere above us, pressing down on our shoulders. For every 10 meters, you go down through the water, pressure increases by one atmosphere. So by a thousand meters, you're at a hundred atmospheres. That's already way beyond anything a human can take. At the bottom of the Mariana trench. You're at 1,100 atmospheres, it is ridiculous pressure. So, the deep sea environment is dark, it's cold, and the pressures are immense. But what about the water? So, we tend to think of the water column as being just a mass of salty water, but it isn't just that, it has structure within it as well. The water column is actually made up of, many different water masses that have different temperature and salinity profiles and therefore different densities. And with that, they also carry, different nutrients, different minerals. And they're also formed in different parts of the world's ocean. So, they actually form in different places and then carry with them, the larvae and the animals, the juveniles of animals from those regions. So, this is a transact taken from a paper by McGrath that illustrates the water mass structure west of Ireland. And you can see there are multiple water masses, west of Ireland. At the top here, we've got Eastern North Atlantic Water, and then lower down, you can see Labrador Sea Water, which is formed in the Labrador sea, off Newfoundland and off Labrador. So, the water column itself, is not just one big homogenous mass. It has structure, and that structure influences the biology. So, I mentioned about photosynthesis and plants and algal life. And we know on land that plants are the basis of the food web. And it's no different in the deep sea environment, bar one difference, which I'll come to later. But the majority of life in the deep sea, still relies on photosynthetic production at the surface in that top 200 meters. So all the life living below that has to rely on matter falling out from the surface, raining down as marine snow or indeed being consumed by all organisms that then migrate down into the deep sea. And are available as energy to other organisms. And only about 1 to 3% of primary production, that primary basis of the food web, reaches the abyssal plain. So, the deep sea tends to be considered as a very food limited environment. And that again has knock on consequences for the animals that live there and their physiology and their metabolism. So, we have these changes in environmental conditions with depth, changes in temperature, pressure, light availability, and also food supply, and also those water mass structures and all of that results in changes in the faunal composition with depth. So, the communities of animals change continuously as you go from shallow to deep. And this is a beautiful map by a chap called Le Danois, published in 1948. He spent a lot of his career trawling, the European continental slope, and this volume really described, a lot of his findings from his work. And so, you can see here, again, a cross section that goes out from Ireland. You can see it just says, Kerry at the top there.(whispers) That's my name. But you can see really nicely illustrated, the change in fauna as you go down the slope and you can see that beautiful, massive coralline, this big coral banks, which I'll come to and talk about later. But really nicely illustrating, how the fauna changes with depth and that you can at different animals at different depths. So, trawls and dredges have taught us quite a lot about deep sea biology, but they also have left big gaps in our knowledge. And one of the most obvious gaps, is that trawls and dredges, only really will work terribly well on soft sediments. You try and trawl on some rocky, rugged terrain, it will rip your net to pieces or snag your vessel and cause all sorts of damage. So much of our understanding of the deep sea, has been based on soft sediment and not the rockier, rugged terrain habitats. The other problem with trawls, is that they tend to integrate information, over a large distance. And so, they give you an impression but not the detail. And I think that's best illustrated by an analogy that was quoted by a chap called Petersen, who was a famous benthic biologist operating around, the early 1900s. So, 1913, I think it was, he published a paper on this. And he said that trawling from a ship, was the equivalent of towing a bucket. I've changed the language slightly, but it was essentially the equivalent of towing a bucket from a hot air balloon and basing your understanding of your capital city, let's say London as we're here, on what you retain in the bucket. So, if you imagine flying a balloon over London, you drop a sort of skip down to the floor. You drag it along for a bit, you bring it back up and you're basing your understanding of London on what's in your skip, right. An impossibly large skip. So, you might have some red buses, you might have some black cabs, maybe some tourists, maybe some people in suits, but what you've lost is the context of all of that. Okay, and you think about it that that collection of things does broadly reflect London, but only very generally. And you've lost the context. You've lost the fact that the buses were on the road, the tourists were on the pavement. They were maybe hanging around the London Eye. The people in suits were over in the sort of financial areas. So, you lose that contextual information. And that's really important. So, in the late 1960s and 70s, and increasingly since that time, the development of camera technology and really the availability of camera technology, and also manned submersibles, enabled people to finally see this environment. So, not just what comes up in a net, but actually go into the environment and see what it looks like. See what's down there and how it operates. And that was an absolute game changer. And I want to illustrate that by showing you a clip from, an expedition that took place in 1973, which used the Pisces submersible III, that's this submersible here, and it was deployed at Rockall Bank. Rockall Bank is a part of the UK's marine area. It's west of Scotland, and a chap called John Wilson, a Scottish scientist, deep sea scientist was in the submersible. And this footage was rescued from a skip, which is very sad (chuckles), but someone was clearing out John's office, after he'd retired and throwing things in the skip. And luckily another scientist spotted the film (laughs) and rescued it. And the heritage film, BBC Heritage Film Group, were able to actually restore parts of it. So, I want to show you this, but what I want you to do is, pay particular attention to what John Wilson's saying. So, try to listen to what he's saying. It is a bit noisy, but just try and hear what the chap's saying.(static buzz)- [John] (indistinct) Pisces, Pisces, dive number nine, dive number nine on bottom in site of sample one. Videotape now shows the colony with the living coral in the foreground and to the left of the picture. We can see the remains of older past generations of growth. These are broken down and are quite extensively covered with serpulids and other epifauna. The living coral appears to be growing down current as we've got a current which can be seen passing across, the colony at the present time, we are now motoring towards the back of the colony to bring, it into focus.(static buzz)(coral snapping) Oh, that's beautiful video. This is probably one of the high points of my scientific career.(indistinct chattering) Yes.(indistinct chattering) well it's, this is the greatest.(indistinct) please come out, (indistinct).- So, I love that bit of footage, because you can hear the excitement in John Wilson's voice saying, this is the highlight of my career. Just being able to see this environment, had such an impact on him, but what was he looking at? Well, he was looking at this. We actually went back to the same site in 2012 to look at the exact same coral thickets. So, these are thickets of cold water coral. And if you could remember what John was saying, he basically was saying the live coral, which are the white bits, you can see on this diagram, appear to be growing down current. And you can see here, the white bits, the live bits of coral, are really only growing on one side of the coral thicket. He talked about the old growth of the colony. He also talked about some of the worms, you could see, which you can also see in this image, fanworms sticking out from the coral habitat. And if you continue to listen to that video, he goes on to talk about how the corals are feeding. So he's watching and saying, oh, you can see that they're feeding on the little crustaceans in the water column. He could see the polyps, clutching these things out of the water column and feeding on them. And I think, it really clearly illustrates the value of imagery and video in this environment, in that, he was able to talk about currents, feeding, growth forms, all of these things, which you could never have got that information from a trawl sample. So, it's incredibly valuable. You can also see from this image, the number of fish in this habitat and it sort of shows, why we study these areas because they are actually important habitats for fish species. So, imagery and video, tells us a lot more about these habitats and in particular, delicate habitats, rugged terrain like coral reef and also rock walls. And it was imagery and video that enabled us to discover hydrothermal vents in 1977. Now, that was in my lifetime, that hydrothermal vents were discovered, which is incredible to think about. Now, hydrothermal vents are these incredible structures. These chimney structures, you can see here and they're formed when seawater seeps through the Earth's crust. It gets super heated by the proximity of the magma, as it warms, it dissolves nutrients and compounds from within the rocks. And then eventually it gets so hot, it's jettisoned out back through the Earth's crust through cracks as these great plumes of hot water. And as it hits the cold water, the minerals in it precipitate out and you end up with these chimney like structures. So this is footage by my friend, Jon Copley, he took these from some of the deepest vents that we're aware of. And the life that lives around vents is really different to the rest of the deep sea. And the reason for that is, that life at vents doesn't rely on photosynthetic material. It doesn't rely on the surface primary production. It actually relies on bacterial primary production and chemosynthesis, so chemical energy. So, many of the organisms like the scaly foot snail, you can see here in the image and the vent shrimp and the yeti crabs, all rely on this bacterial production as their source of nutrition. And they can be quite close to the warm water. And they've got some really unique adaptations that allow them to live here. So, the scaly footed snail, actually has a shell made out of iron, and it has this armor plating all along its foot. And that's really quite unique in the world. And they were only discovered fairly recently as well. So, imagery and video has helped us to discover, brand new habitats in the deep sea that we were previously completely unaware of. And, in recent times, we have been using increasingly robotic technology. So, here you can see a couple of the, National Remotely Operated Vehicles that I've had the great pleasure of using. So, the UK's National ROV "ISIS," and then the Irish National ROV "Holland 1." There's a picture of me there for scale. These are enormous robots. They're really large. And they have these great arms at the front that are used to pick up animals. And you'll see some of that in the moment and then underneath they have trays, where you can store those animals and you can bring them to the surface and study them intact. But they're also equipped with very high definition camera systems, multiple cameras, and the footage you can obtain to study this environment is really incredible. So, you can see here, the ISIS ROV being launched from the James Cook, it's a national research vessel and the control room is quite incredible. So in the top image, you can see a view from the back of the control room for this robot, and you can see all the screens and at the front, there are three pilots. You need three pilots to control these things, one for each arm and one for actually driving the vehicle. And then toward the back is another set of screens. And that's where the science team sits and makes scientific observations and can direct the pilots to where they want to go and what they want to do. And you can see on the bottom here, there's an image of me in my, doing my best Cousteau impression in the hat, looking at those screens and directing the science. And they enable us to observe animals in their natural habitat. And that's really valuable. So here you can see a cold water coral reef. So, previously I showed you just a thicket, this is a full reef, and these habitats apart from being very beautiful, but just like shallow water coral reefs, are really important habitat for lots of other species. You can see here, a crab going for a stroll, through the reef structure. But many organisms use these cold water coral reefs as feeding grounds, as nursery grounds, as shelter. And so, they're really important to the deep water ecosystem. And again, only really possible to study these areas properly with imagery data. If you trawl through that, you completely destroy it. And this robotic technology is also enabling us to take samples. Now, this is not an easy task. You can see here, the robot's arm, which is picking, it looks like it's picking a flower. That's actually a sponge. It's called a tulip sponge, but it's enabling us to take really precision samples of animals. When you trawl animals, they're in the back of the net, you get rocks in the net, they can get quite damaged. And so, actually, if you want to study them, if you want the opportunity to potentially bring them back, keep them in an aquarium, understand a little bit about their physiology. Then you need to be a bit more careful about how you sample them. So here you can see the two arms, there's two different people operating those arms, one on one arm, one on the other arm and the person driving the whole robot. And so, they have to have incredible communication between them to do this. It takes a lot of skill to do this work, and it takes time, even with the best pilots, picking stuff up takes about 15 minutes per sample. You can see here, the sponge is about to be slurped up with the slurp gun. So, it just works a bit like a vacuum. And in a minute, their arm will release and you'll watch it suck up the pipe. There you go (chuckles).(audience laughing) So, it ends up in a tank on the back of the ROV, perfectly preserved, and then the ROV can return to the surface and we've got a beautiful sample intact. And in fact, this robotic technology,(calm music) has also enabled us to do, experimentation. So, I'm just going to show you a quick clip of the Jason robot. That's almost identical to the ISIS, but you can see here, the arm of the robot holding a thermometer and the thermometer is being placed, directly into the plume of some of the hydrothermal vent water. So, we can take very accurate measurements of temperature of these vents, and that just simply wouldn't be possible without this technology.(calm music continues) So, the ability to manipulate things, has, again, opened up our ability to study this environment. So, our knowledge of the deep sea has grown with technological development. And that is the way it is for deep sea. The two things go hand in hand. But I want to change tack for a moment and show you a picture of the Moon. Why am I showing you a picture of the Moon? I'm sure you've all heard. We know more about the surface of the Moon than do about the deep sea, okay. It's not true, of course, we know way more about the deep sea and there's more to know about the deep sea, right? There's a lot more going on, so it's not true, but it is true in one very specific way, which I'd like to talk about next. And that is in our understanding of the topography of the shape of the terrain. So, the Moon has been mapped a hundred percent. The whole surface has been mapped at a hundred meter resolution. So, what that means is that if you superimposed a mesh grid around the surface of the Moon for every a hundred meter by a hundred meter cell, there's a piece of information about the surface. Now that's true of Mars, as well. So, we've mapped Mars completely at hundred meter resolution. The ocean floor, we've only mapped about 20% of it at less than a kilometer (chuckles). We can't map it all at hundred meters. Well, we could, but it would be impossibly hard. So, we've only mapped about 20% of our ocean floor at that resolution. So, it is true in that very one respect. We do know more about the shape and the surface of the Moon and Mars than we do about the sea floor. And you may be thinking, well, but I've seen a map of the sea floor. If, you go on Google Earth, you can have a look at the ocean on Google Ocean. You can see there, the lovely Mid-Atlantic Ridge, running down through the middle there. You can see all the lumps and bumps of the terrain, and you can think, well, we have got a map of the sea floor and we do, we have a map of the sea floor, but it's only at a resolution of about five kilometers by five kilometers. And it's not really a map in the sense of, we have seen the shape of the sea floor, the way in which the sea floor is mapped. How that map was generated, is using something called satellite altimetry. So, satellites, we can use radar to detect anomalies in the surface of the ocean. And the surface of the ocean, is distorted by the shape of the seabed underneath. So, large features like underwater mountains or troughs, actually distort the surface of the ocean. And we can measure those distortions using satellite radar. And from that, we can infer what the sea floor looks like. And that's how those maps are created. They're an impression of what the sea floor looks like, based on this technique. And they are then supplemented with higher resolution data from actual mapping where we have it. So, in the north Atlantic, the resolution of our maps of the sea floor is actually not bad at all. It's quite a lot higher than five kilometer by five kilometer, but in the south Atlantic, for example, which is really poorly studied, our maps are really not great. And just to illustrate the point, in 2019, I was out on a expedition mapping underwater mountains in St. Helena's Exclusive Economic Zone. The EEZ. So, St. Helena is a British overseas territory in the south Atlantic. It's an oceanic island system. And there are a lot of seamounts around St. Helen. We were there to map those seamounts. And at one point, the acoustic methods we were using to map, so, sound, echo sounders, were telling us that the sea floor was at 2,500 meters, on our chart, said it was 200 meters. It was 2000 meters out (chuckles). So, in some parts of the world, our maps of the sea floor are really not good. And the south Atlantic is one of those examples. But, what's exciting is that, there is an initiative to try to map the sea floor and map it using acoustic methods. So, I'm sure you're all aware of ship's echo sounders. So, we fire sound at the seabed. You wait for the sound to come back, you know the speed of sound through seawater. And so you can work out the depth that you are at. Multi-beam systems, are essentially like single-beam echo sounders, but they fire multiple beams of sound out at once, creating a big swath of information on the seabed, as you can see here. And so, you get a big swath of terrain information at once. And so this technique is really, how we're going to be able to achieve, better and more highly resolved maps of our sea floor, but it's a long process. And it takes time. And this project Seabed 2030, which is a UN endorsed program, under the decade of ocean science for sustainable development, which we are now in, runs from 2021 to 2030. This project is aiming to map the whole of the sea floor of our ocean by 2030. So, it's a huge global effort to try and actually, finally get a decent map of the seabed. And that's going to tell us something about the terrain, but what about the biology? Well, much less than 0.001% of the total deep sea has been sampled. So, that's physically, someone has gone there and seen it or taken a sample or done a trawl or physically got some sort of specimen. So, there's a lot left to learn in terms of the biology. And there is another initiative, under the UN Ocean Decade called Challenger 150, a new Challenger, which is hoping to learn more about the biology of the ocean over the next 30 years, and in particular, employing new technologies to help do that. So, I want to just mention new technologies and the future of deep sea science. So, we are increasingly looking to autonomous robots, now. I'm going to go back and just play that again. So, autonomous robots are robots that, are not tethered to a ship. They're not controlled by a pilot. They are programmed to just go off, roam around the ocean, taking samples, well, measurements of physical properties of the ocean, but they can also take imagery of the seabed and then return with terabytes and terabytes of image data of the sea floor. So, they can bring us back that imagery and they can achieve huge coverage. They can stay down much longer than ROVs can stay down. And they have the potential to absolutely revolutionize our study of this environment. And they return images of the seabed like this one. This is an image that comes from the Autosub6000 AUV, again, UK National AUV, and then that imagery data has to be analyzed, by someone. Now, analyzing imagery data is difficult. You have to spot the animals, you have to be able to identify them. So, it's skilled work. It's extremely labor intensive. And basically, it really does do your head in after a while.(everyone laughing) So, I mean, most people can only stick at analyzing imagery for a few hours a day. It really is incredibly laborious, lovely to look at the animals but it lot of time and observers tend to become tired. And when they're tired, they start to make mistakes and those mistakes are inconsistent. So, they're errors and they're inconsistent errors, even with the same person doing it. So, there've been some really great experiments, where people have analyzed images and their two months later, analyze the exact same images. And the agreement between themselves is not great. And actually another problem then with this is that, different observers have different biases. So, some people particularly like certain taxa and other people are particularly good at other taxa, and they'll tend to favorably spot those taxa. And so, different observers, you will get a bias in the data from as well. And so again, that introduces a level of error, when trying to put your data together, which makes things difficult. And so, we're starting to look, now, at using artificial intelligence, deep learning and computer vision, as a means to identify species and interpret some of this image data. So, I'm sure you're all familiar with computer vision. It's the sort of thing that's used in self-driving cars, for vehicles to interpret the world around them. It's used in things like analyzing sports footage to look at performance of athletes or particular plays. So, we're already in a situation where these tools exist. They just haven't really been applied to the task of interpreting deep sea imagery, funnily enough. And so, we've been looking at the possibility of using this technology in the deep sea to identify animals. And with some success, so this is some footage from earlier this year, we went out, west of Ireland again, with the ROV, and this is live ROV footage that is coming up from the seabed. And a computer is spotting these little muddy balls on the seabed called xenophyophores. You can kind of just see them there, but as they come onto the screen, the computer is spotting them, putting a box around them and saying, it thinks it's a xenophyophore, and giving you a sort of probability of it being a xenophyophore. So, you can see how confident it is in its assessment. And we've done earlier tests with this as well, looking at multiple species, different taxa and seeing how well artificial intelligence does in identifying species and the initial results are that for some species, strangely, xenophyophores, it does really well. It's very good at spotting them. For other species it's really not very good at all. So for some kinds of anemones, it just can't spot them at all. So, there's still a huge amount of investigation and work to be done to see if this really has any legs for the future, but I'm pretty certain it does. And I think over the next 10 years, we are going to see some significant advancements and, we may, I'm pretty sure we're going to get to the point, and maybe by 2030, of having autonomous vehicles that can go out into the marine environment, they can be mapping. They can be doing multi-beam. They can be taking physical measurements, measuring the temperature, the depth, the salinity, they can be photographing the sea floor and they can be interpreting the animals they see and turning that image data, straight away, into semantic observation data so that when they return to the surface, us, biologists have got all of our data. We don't have spend two years interpreting a single dive of the AUV. And so, I think this is where we're headed. And in terms of increasing the amount of data that we can obtain from the deep sea and the amount of, I guess, sea floor we can cover, it's going to be revolutionary. It's also going to open up a world of possibilities. And it may be, that we will end up with something a bit like, the Mars Rover. I find it incredible that we can send a robot to another planet and it's capable of roaming around, taking samples, beaming images back to earth, analyzing rock samples and sending that information back. And yet, we are not yet in a position to be able to do that on our own planet, in our own deep sea, but I think we're not far away. And oddly enough, I think it's actually space exploration that's going to solve the problem for us, in that, there's this moon around Saturn, which many of you may have heard of called Enceladus. And Enceladus is an ice covered moon. And underneath the ice is an ocean, an alien ocean. And at the moment, space scientists believe that, there are hydrothermal vents in those oceans. There's evidence of venting that they've observed. Great geysers that are jutting out from beneath the ice surface. And so, there may well be hydrothermal vents on Enceladus. And so, there is now a mission, a very long-term mission to take autonomous robots to Enceladus and explore the ocean under the ice. And so, in fact, I think it is space science that's actually going to stimulate, the development of these robots for deep sea science because they will inevitably be tested on our planet first and make sure they actually work before they're sent off to go and do anything cleverer in space. So, with that, I think the next 10 years has looked to be pretty exciting. I thank you for your attention, and I'm very happy to take any questions, if you have any.(audience clapping)- So, the first question is, is the artificial light used to film the deep sea, very strong/bright? And do we know if it is at all disruptive? Do life forms swim away or towards the light, for instance?- Yeah. So yes, it is. I mean, it's obviously brighter than anything that's down there. Many of the animals can exist. So, in the top thousand meters, a lot of the mobile animals do migrate. So, they experience sunlight and then they come back down, again. So for them, I think it's less of a bother, for animals deeper than that. It invariably is doing something. Now, there are some fish which actively avoid, the lit up areas. And then there are others that actively swim towards it as well. And it tends to be the Chimaeras. So, these are a type of relative of a shark. And, lot of the crustacean life is attracted to the lights around the robot. And so, that then brings in the predators, who want to come and eat the crustaceans that are swimming around the ROV, but there are definitely species that actively avoid the light. And I think there is a need for, research into the effect of light pollution on some of these organisms. So it's something we definitely need to look into, more than we have.- What happens when you bring up a living organism from high pressure, deep environment to the lower pressure surface?- So, it depends on the organism and it depends on the, again, the depth from which they're brought up. So, from about, anything above about a thousand meters seems to be okay, the animals will still be alive. They won't necessarily be, in incredibly good condition, physically because it is a depressurization, but the invertebrates are usually fine. From deeper than that. Pretty much, things tend to come up dead or moribund. Because the depressurization is so great. And so, you do get animals that are swollen, very much expanded because they've come from a very high pressure environment, up into a much lower pressure environment, tends to swell them up. So yeah, it's not, yeah, they don't tend to survive when they're brought up from the abyss, for example, that's just not possible. And that means it's not really possible to keep them in labs or anything. And again, it makes it very hard to study these animals in anything but, in situ, because you can't bring them up and keep them in labs and observe how they behave. You have to do everything in situ, which limits what we can do.- And one more from the online audience, how long would it take to get to the bottom of the Mariana Trench with a robot submersible?- That's a good question. I should have worked that out. It does take quite a long time. So it takes, I'm going to say something like nine hours or so. Well, maybe maybe six to, yeah, six to nine hours or so, I would say. The bottom of the Mariana Trench, probably more like nine, it takes about six or so to get down to the abyssal plain and there's quite a way to go after that. So yeah, it takes a long time (laughs).- And one more, just one more because we do have a nice period of time for questions. How hot are those hydrothermal vents and how common are they?- So, hydrothermal vents do range in temperature. There are some that are around sort of 250 degrees C, and the hotter ones are more like 350 degrees C. So, really very hot. It's interesting about, how common they are. So, we know about, not that many. So, on the basis of it, it would seem like they're not that common, but the fact is, the animals that live on hydrothermal vents, hydrothermal vents are ephemeral. So they don't last forever. They go extinct and the animals that live there, have to be able to move between vent sites. They are not endemic to a single vent site. They move between them. And an animal larva can only disperse so far. So vents must be more common (laughs) than we know about, but there's so much of the sea floor we haven't looked at. And it really is like looking for a needle in a haystack. You're trying to detect the plume, I mean, that's how we spot vents. We send equipment down to try and detect temperature anomalies, and that's how we spot them. So, it really is quite difficult to find them. We know the sorts of areas, we're likely to find them. So, on the Mid-Atlantic Ridge, so, where you've got rifting, where you've got any kind of, cracks in the Earth's crust and tectonic activity. Those are the places you get vents. So, we know where to look for them, but they're still quite hard to find.- [Female Audience Member] I was wondering that, considering how little we know about the deep sea, what do you think about deep seabed mining? Is it a good idea?- I don't think it's a good idea to, develop an industry in an area until you understand the impacts of that industry. We are trying to be, we're trying to move to a more sustainable way of operating. The human race has a terrible history of doing things first and worrying about the consequences later. And we have to move away from that. So, that's not to say that there might not be a possibility for conducting deep sea mining, but I do think it's important that we understand those impacts and have the data to make sensible decisions before we go and enter into any kind of new industry. And I think what's most disturbing at the moment is that, one of the areas that's being licensed for exploration for deep sea mining is a place called the Clarion-Clipperton Fracture Zone in the central Pacific. And recent expeditions to those areas, admittedly, related to the development of deep sea mining, is the reason those expeditions were out there, but they're discovering that sort of 90% of the species are new to science. I mean, that's just 90% of the species (laughs) are new to science. That's not even what do they do? How long do they live? What's their role in the environment? What's the impact on them going to be, if you start mining? Let alone those questions, this is just, oh wow, we didn't even know they existed. So, I do think there's a case to be made for, just pausing and spending some time studying, gathering the data to make good decisions.- [Female Audience Member] One of the big worries I find, because I've been doing a book on nature, is what protection measures are you putting in place to stop any more environmental damage?'Cause I noticed on that first bit of footage with the 1974, this guy going into the coral and behind you, you can hear the coral breaking.- Yeah.- And it's really upsetting.- Yeah.- And I was wondering, as a scientist, what policies, what measures are you taking to,- Yeah.- really safeguard the future?- Yeah, no, and that's a good question. So, scientists are as much, have to look at what they're doing and make sure they're behaving responsibly as any other industry does. And we do as a community, the deep sea science community, have developed codes of conduct. So, we have a particular code of conduct for working with, for example, deep sea corals, which live for, hundreds and in some cases thousands of years. And so, we have a protocol about collecting, how many we collect the purpose of those collections, taking care, not trawling, we're increasingly moving to image based analysis. I mean, we're not going to be able to do that for everything, but we are increasingly moving in that direction in order to not damage (laughs), the very environment that we're trying to study. So yeah, so, we do have codes of conduct and I think there's more we can do there, but we are aware of it and have been working on it.- [Male Audience Member] You refer to the continental shelf and the deep sea. And are there areas where there's are more gentle slope? And is that a separate zone, and how would you define the deep sea if it is a gentle slope,(indistinct) down (indistinct) level?- It's a good question. So, the deep sea, yeah, there are areas of the slope that are more gentle and more so there are areas of the slope that are incredibly steep. So if you think about oceanic islands, which are really just underwater mountains and the top of them are poking out, they're incredibly steep. There is no continental shelf at all. And so, there's this interesting kind of conversation about, well, how do you then define the shelf if there is no shelf, it's just seamount. And so, I think we're trying to kind of break down, the barriers a little bit and the definitions between deep sea, particularly because, actually it turns out that, the area of the marine environment we know most about is, the bit that you can reach as a diver. So, we've got a lot of information from the coastal environment. And from depths of sort of down to about 30 meters or so. Below that, the amount of data just drops off completely, whether you're on the shelf or in the deep sea, it doesn't matter, we just don't know a lot about deeper water. So, I think we're increasingly, being less strict about the definition of the deep sea and just thinking more in terms of, deeper water environments. But yeah, it's a sort of flawed definition. That's very much based on a European centric(laughs) terrain.- [Male Audience Member] Can you just tell us, a little bit more about new species? You alluded in that, what you were talking about the commercial discovery of new species that (indistinct) going on? And I was shocked by that number, is quite so many. Can you just talk a little bit more about, the rate of discovery and what that might look like?- Yeah, so the 90% of new species, I mean a lot them, well, they were very varied taxa. So, they were, things like worms, but they were also corals, there were sponges. I mean, it was spread across, quite a number of different fila, the different groups of organisms. And it's because I think we were studying, they're studying out there, these nodules. So, the manganese nodules are, what the mining industry's interested in, but a number of species use these nodules as hard substrate habitat. So, they're living on them. And then they have their own unique fauna, microscopic or meiofaunal organisms that live within the nodules themselves. But so, the animals were varied in size. They weren't just really tiny things, they were from across different taxa. And yeah, I mean, it was astonishing to me,(laughs) that there were so many new species, but it comes from, again, this problem of limited exploration in some of these areas.(indistinct) the Clarion-Clipperton Fracture Zone, had an extremely limited number of samples from there, before it was licensed for exploration. And since it's been licensed for exploration, the amount of data from this area, has exponentially increased, because so many nations have sending ships out there to see what's there. But every time, and even in the north Atlantic, every time we go out, we see something, discover something new. The rate of discovery in the north Atlantic, is much lower, but you go somewhere new, like the Clarion-Clipperton, potentially the south of Atlantic, areas that we've really not studied at all. And it's a no brainer,(laughs) you're going to find new species. There's a lot of things out there. So, there is a huge amount left to discover. And yeah, so before, I hope that we take the time to see what's there, before we decide to use it in some way.- I did want to note that this is the first in a six lecture series on natural world extinction, exploration and adaptation. And the next lecture is on coral reefs in a warming world by Professor Nick Graham. And that will be on Monday the 28th of February at 6:00 PM. So, please do join us for that, but I hope you'll also join me in thanking Professor Howell for a fantastic lecture this evening. Thank you so much.(audience clapping)- Thank you.