Diversity in a Changing Ocean
- Hello and welcome to today's Texas Science Festival Session, Diversity In a Changing Ocean, with Andrew Esbaugh and Brett Baker. We're glad you've decided to join us. My name is Ed Buskey, and I'm the department chair for Marine Science at UT, Austin.
Today happens to be World Water Day. So we're especially glad that you decided to spend that time with us. Please note that all participants will be muted, and without video for the duration of the webinar.
Because this is one of our Science Sparks events, each speaker will talk for about 10 minutes and then we will move on to questions and answers. Please use the Q&A feature by hovering over the bottom center of your screen at any time to submit questions you'd like to ask our speakers. We also have any pre-submitted questions you provided and we'll do our best to get through them when we can. I'd now like to introduce Andrew Esbaugh, associate professor of Marine Science at UT, Austin. Andrew is a co-principal investigator with Recover to a major project supported by the Gulf of Mexico Research Initiative, studying the Deepwater Horizon Oil Spill in the Gulf of Mexico. And he was the recipient of the best oral presentation at the annual meeting of the Canadian Society of Zoologists.
Andrew, take it away. - Thank you, Ed, and I'd like to thank everyone who's taken the time to join us this afternoon. So today I'm going to be talking about some of my work on climate change, specifically, how fish are dealing with this prospect of a changing ocean.
I'm gonna start with a slide that maybe many of you have kind of seen. This is a depiction of, or a prediction of surface temperatures across the globe for the end of the century, as compared to maybe 20, 30 years ago. And what is apparent from this heat map is that, global temperatures are going to go up, and they're going up at very different rates, depending on where you are in the world, with the Northern latitudes seeing a greater change than what you're seeing in the more equatorial latitudes. But one of the things that this type of image kind of belies is the fact that in the ocean, climate change is a much more dynamic stressor, it is not just warming. In fact, climate change impacts the ocean through a combination of three different environmental stressors. One of those is warming, increased temperature, but we also are seeing increases in dissolved carbon dioxide in the oceans.
This is a phenomenon known as ocean acidification. And then in addition, something that is a little less talked about, but is no less important, which is ocean deoxygenation, or the tendency for the world's oceans to have less oxygen in a warming environment. This is both because water just holds less oxygen when it's warm, but also because there's this predicted proliferation of something we call oxygen minimum zones.
For people in Texas, they might be familiar with this term because one of the largest seasonal oxygen minimum zones occurs in the Northern Gulf of Mexico every year. But these types of zones are predicted to increase in size, increase in duration, and increase in occurrence, with the onset of climate change. So one of the things that my lab is really interested in, is how these three stressors combined impact fishes. And this is particularly of interest to us because we're respiratory physiologists, we study the respiratory system of fish.
And all of these stressors are inherently respiratory problems. What we mean by respiratory problems is that they impact the ability of the animal to extract oxygen from the environment and deliver it to its tissues, to its muscles, as well as the ability to take carbon dioxide that builds up inside the body of the animal, as a consequence of metabolism and remove it from the body. So climate change is interfering with both of these processes. Now, one of the important things to remember about climate change is that it's not going to impact all animals in the same way, or all fishes in the same way. And this can be true across different species where some species will be fine and other ones will be very sensitive. But it also can apply within a population where some individuals will be considered sensitive, and some individuals be tolerant.
And all of this is based on the individual physiological characteristics, of those individuals or those species. And the significance of this is kind of played out in this concept called evolutionary rescue. I just love the name of this concept, it makes me think of evolution as a superhero.
But if you look at this graph, I can kind of explain this concept very quickly and hopefully pretty simply. So consider here where my cursor is, this is all of the individuals present in a population. Then an environmental stress is exerted on that population. Individuals that are sensitive to this environmental stress are ultimately gonna die out. And that's gonna result in this reduction in abundance of the species or the population. However, this blue line denotes individuals that are present in this population under normal circumstances, that have the capacity to tolerate this new environmental stress.
So as the environmental stress removes the weaker individuals from the population, the stronger individuals are gonna grow in abundance and eventually start to dominate. At some point, this growth of these stronger individuals is going to turn the tide of this population decline, so that population starts to rise again. Now, the important thing about this type of concept is trying to understand why animals might be considered sensitive and why animals might be considered tolerant. 'Cause that allows us to better predict what's going to happen with climate change. And in the context of fishes, something that's popped up a lot is this idea that certain individuals or certain species, that are found in variable environments might actually have the genetic capacity to survive. So for example, take this beautiful mahi-mahi.
Mahi-mahi are typically found in the open ocean, they typically move to maintain a very stable environment around them. So in other words, they can migrate hundreds of miles just to make sure that the temperature of the water they're in is about the same. If you contrast that with another popular sport fish, the spotted sea trout, these animals live in coastal estuaries across the Gulf of Mexico. And these coastal estuaries are actually really dynamic environments. They can shift quite widely in temperature, especially in the early summer, over a two week period, the temperature that they might experience can go up by 10 degrees.
The carbon dioxide in these environments can also be highly variable because of the primary production that occurs in the estuary. Similar with the oxygen, oxygen can be quite dynamic where it can go down and up, even within a single day because of plant respiration. So this comes with the, or leads to the hypothesis that the animals that are kind of found in these estuaries, such as the sea trout, might be considered, or might have the biological capacity to tolerate environmental stress better than the mahi-mahi. And this is something that my lab is really, really interested in. Trying to understand if certain environments that currently exists might hold the keys to tolerance with respect to climate change.
Now, one of the ways that we study this is through some concept known as phenotypic plasticity. Phenotypic plasticity is a really, really strong trait that allows individuals or species to tolerate environmental stress. And it's a fancy word, but really all it means is that these animals are able to change their bodies to cope with an environmental stressor.
Now, I'm gonna go through a kind of a case study that we're working on now in my lab related to low oxygen. So how does low oxygen impact fishes? Well, it does it by interrupting how much oxygen the animal can consume, as a consequence of activity. So if you look at this graph here in the bottom, this is just a representation, a theoretical representation. And on the Y-axis, this is oxygen consumption, or how much oxygen the animal is consuming at any given time.
On the X is just your oxygen found in the environment. Normal would be considered on the far right of the graph, my cursor is right now. The blue line represents how much oxygen the animal needs just to meet its standard or baseline cost of living. What I mean by that is imagine how much oxygen you're using when you're lying in bed hitting the snooze button in the morning and you refuse to get up.
That is just the amount of oxygen you need just to survive. If you contrast that with this red line, this is the maximum amount of oxygen the animal can actually get through its system. This is equivalent to the amount of oxygen you would need if you were running a marathon. The difference between these two things is something we call aerobic scope.
Aerobic scope is a really useful metric because it really accounts for all of the energy that an animal uses or has access to, to perform the every day things that allow it to succeed in the environment. Now, this could be a movement, so for example, capturing prey, avoiding predators, fighting for territory, it also accounts for the energy that can go towards growth, as well as reproduction. So you could see very quickly that it's a very, very important thing. Now, interestingly, when an animal is exposed to lower oxygen in this case, denoted by going left on this graph, the amounts of maximum energy available to the animal starts to decline. And this is because of a respiratory constraint. The animal isn't able to extract oxygen to the same degree.
Eventually aerobic scope falls to zero, and that's a point known as the critical oxygen threshold. Below this point, the environment is no longer sustainable for the animal. They'll essentially not be able to get enough oxygen from the environment to meet their just baseline cost of living. So one of the ways we measure this type of stuff in the lab is through tools like this, what you're seeing in the video on the top. This is a swim tunnel respirometer. This is essentially an airtight chamber that we placed a fish in, and there is a water flow that runs against the fish that the animal must swim against.
What you can see down here on the graph on the X-axis is swim speed, so just the animal swimming faster and faster and faster, on the Y is the oxygen consumption? And what's hopefully is very apparent is that as the animal starts to exercise, they start to use more and more oxygen until they get to this point at the end. This is known as the critical swim speed. And you're gonna see what happens at the critical swim speed in the video here in a moment.
But essentially the animal fails at this point. And when this happens, we can denote that period, I think you just noticed failure. You can describe this period as the maximum energy consumption. That's the amount of energy, the maximum amount of energy that the animal can use. You extrapolate the same curve back down to zero, and you get the minimum energy consumption that the animal requires to stay alive.
These are the metrics that we can use to calculate aerobic scope. So what's really interesting, is the idea of how animals might manipulate aerobic scope through phenotypic plasticity. And this is actually the subject of one of my students' dissertations shown here on the slide, Ben Markready, and he came up with the idea of, well, what happens if an animal such as a red drum, a very popular sport fish here in the Gulf of Mexico.
What happens if these animals are exposed to hypoxia for just say, two weeks. Will they actually be able to change their physiology to better perform in this new environment? And in fact, they do. So if you look at this graph, again, you have controls here on the left, don't worry about the gray and the yellow, they're just different types of exercise protocols. Versus, right here is the hypoxia, so you're really comparing the control here to the hypoxia here. And what's hopefully apparent is that when you acclimate red drum to hypoxia for, like I believe this, this was eight days, you see a significant increase in their ability to extract oxygen from the environment. They're able to better extract oxygen, and therefore meet the energetic demands of this new environment.
In addition to this, they're actually able to lower that critical oxygen threshold, which means that they're better able to fight off the kind of unsustainable stress that might come with low oxygen. Now, how do they do that? Well, there's a lot on this slide but it's actually not that complicated. So if you look up at this graph here on the top, this is something we call real-time PCR or gene expression.
It's just a measure of how much a gene is expressed by the body. And in this case, by the red blood cells. And what Ben was able to find is that one particular protein started to get heavily expressed when the animal was exposed to hypoxia. And that's denoted by this green line, which is well above all of the other lines. What happens is when red fish are exposed to this low oxygen, they start to increase the expression of a very particular hemoglobin protein that they keep in the blood. Then Ben tested the blood to see if that hemoglobin performed at a better rate than what would happen under a control condition.
And so if you're looking at this graph, the Y-axis here is just, just consider this the percentage of hemoglobin in the blood that has oxygen on it. Up here, it's all saturated, it's 100% oxygen bound hemoglobin, down here, there's no oxygen on hemoglobin. And along this axis is just how much oxygen that the solution is being exposed to. What I hope is apparent is that these dotted lines, across the entire span, are higher than these solid lines.
These dotted lines represent the hypoxia acclimated fishes. And the solid lines represent our controls. So what is apparent from this is that the red drum, when they're exposed to hypoxia, they change the hemoglobins that are in the blood, and that these new hemoglobins are actually better able to extract oxygen from this hypoxic environment. That's gonna make them perform better in these types of low-oxygen situations.
So since I'm pretty much out of time, let's just sum this up with some big picture stuff. Climate change is going to have winners and losers. It's not going to impact all species the same.
And that's why concepts of biodiversity are really, really important when discussing things like climate change. Generally climate change is going to impact fish through respiratory stresses. That can be through oxygen, carbon dioxide or a combination. But as we've demonstrated here, some species or individuals are resilient owing to the existing physiological traits in their body that can at least somewhat offset the stresses of climate change. But it's really important for us to understand why species and individuals are resilient because it will allow us to better predict which species might be sensitive, but it'll also allow us to kind of explore questions of well, are there trade-offs? What is the consequence of an animal that adapts to climate change? Does it have to give something up? And those are all really, really important questions when we're trying to predict what's gonna happen.
And with that, I will end and take any questions that you might have. I think I can stop sharing. - Okay, thank you very much, Andrew.
That was a great talk, very informative. Now let's answer some questions that were submitted by the audience. Okay, here's one from Ellie.
How are your study findings put into practice? Are there any organizations that use them to fight climate change? - That's a really good question. One of the hardest things for physiologists in general is what we call translatable data, which is how to properly get this data in the hands of the decision makers. And right now I think it's still a bit of an abstract concept, unfortunately. We identify species that might be at risk, species that might be tolerant, and try and work with agencies, just say Texas Parks & Wildlife, other government agencies, about identifying particularly sensitive species. But a lot of what we do ends up being really broad global work when it's much harder to kind of put some of that stuff into real practice, because you're working across country lines, and there's a lot of politics that goes into it.
- Okay, we've got another question here. Elizabeth is asking, are we able to do oxygen training on a large scale? - On a large scale, yeah, that's a good question. I think that on a large scale, the climate change is going to do that for us.
But if we were gonna try and actually exercise a whole bunch of fish, I've seen experiments where people do it in groups. But it all comes down to what your scale that you're looking for is. I think it's more likely that this type of data and this type of information is important for decision makers and regulators, to be able to identify which species might be most at risk and which species might essentially succeed in a new environment like... Climate change, when it removes those sensitive species, it's also gonna open up ecological niches for species that are considered tolerant. And then we have to try and say, okay, well how's that going to impact the fisheries industry? How is that gonna impact all the economics around fisheries? Those are really kind of the ways I see this kind of helping.
- Okay, here's another question. Kathy is asking, are there any species that are particularly at risk of climate change and is there anything we can do to help? - Yeah, well, that's a two-parter. So yes, there are species that are particularly at risk. So some of the, I think most dire species that I've seen are the ones that are living in really warm or cold environments, so kind of at the extremes. So if you're looking at the polar environments for example, they don't have anywhere to go.
As temperatures warm up, a lot of fish that might essentially go through what they call latitudinal migration, they'll start moving northward. If you're already, as far North as you can go, or far South if you're in the South pole, then there's no kind of room, that you're... Those are the species that are kind of at most risk. Similarly, there are certain species along equator, specifically associated with coral reefs that they're consensually living at the warmest part of their range, but they're kind of constrained there because they have to live on these coral reefs.
And so they don't really move very much. So those types of species are the ones that people have the most concern about. And based on our work, you add in that if they live in an habitat that tends to be stable, that they're probably going to be more at risk, than if their habitat is naturally fluctuating widely in temperature, or oxygen, just say like our Texas estuaries. - All right, Christine is asking, as the oceans warm, would we expect fish behaviors to change in ways that would affect the health of other animals or people? - Yeah, so the behavioral stuff is really interesting.
And that gets into one of those trade-offs like I hinted at the end. So when animals constrain or have a constrained energetic availability, what can happen is they might stop moving around as much. And so when you're talking about health to society, now to people, maybe not, but if, unless you're talking about it as a food source, no. So that is how it's going to change fisheries economics and food security, I think is a really, really important issue. There are a lot of people who rely on the fisheries industry for both their livelihood or their food supply. And those, I think are the places where things can really impact humans the most.
- Okay, I think that's the last question. So great, thank you very much Andrew. - You are welcome. - Today's next speaker is Brett Baker. He's an assistant professor of Marine science at UT, Austin, and Brett was awarded the Sloan Foundation Fellowship in Ocean Science in 2016, and a prestigious award last year to advance work by his team, overseeing The Moore-Simons Project on the Origin of the Eukaryotic Cell.
Take it away, Brett. - Okay. (indistinct) All right, so I'm gonna talk about organisms much smaller than what Andrew's talking about.
So we're gonna move from fish to very small organisms, but very important ones, microbes. So I'm a microbiologist. And what I'm gonna talk about today is a lot of the unknown.
The unknown to me is very, very exciting. So I like to think of, and it's true, that our microbiologists very much relies on the tools they have at hand to study them. So if you go out to the beach or to a lake and you take a drop of water, and you put it on a microscope. This thing with DNA, this is what you see, essentially these little dots. Each one of these dots is an individual species, an individual organism like you and I in that community.
So I like this image 'cause it reminds me of looking at the sky at night, and I have this very same wonder when I look under a microscope or when I look through a telescope, there's a lot of similarities in these things. And so just for fun, I like to sort of just do a quick measurement, based on how many cells we know there likely are in the oceans compared to the numbers of stars in the universe, to get this really large number, and this is just in the oceans, right? And when I say that we rely on our tools a lot, I mean, a lot of the basic questions of microbiology are really trying to be addressed. And one of them is what's out there.
I mean, just understanding the biodiversity of the ocean, of any natural environment, is a real challenge and has been for a long time. So what are these tools that microbiologists have at their disposal to study microbes? Classically it's relied on sort of culturing. So taking your sample, trying to grow it on a Petri dish in the laboratory, and understand it in that way.
Well, we now know that from doing this from other approaches, we've now learned that only about at best about 1.1% of what is actually present in nature can actually be grown in a laboratory. And so people, the microbiologists, a lot of us like to refer to this as microbial dark matter.
So similar like to what dark matter in physics, we have a limited understanding of what it is, but we know it's there. So what approaches have been developed, in the last say, 15, 20 years to sort of circumvent this, what we call it culturing bias, or relying on growing stuff in the lab, we use DNA sequencing to study microbes in nature. And so the approach that my lab uses a lot is called metagenomics. Essentially what the fancy name is, is taking your sample that you're studying, extracting all the DNA from that, so you're getting all the DNA from all the organisms in that sample, and you put it into sequencer and you get individual pieces. Now we use computers, very large computers, to sort of put those individual pieces into genomes that were present in the sample. And so from this, once we have a genome, we can actually go and say, okay, look, it has this metabolic pathway, It can likely do this process, and we can actually say who's there.
And so this has been a real game changer for microbiology, because it's enabled us to essentially look at the biodiversity and the function, the ecology of communities without having to rely on culture. So I wanna step back a bit and I wanna talk, sort of introduce this concept of the tree of life. And so tree of life is really a central theme in biology in general. And it started with Darwin, when in 1837 in his field notebook, he wrote this really remarkable tree shown here on the left.
And he wrote, I think. And it's pretty amazing that he drew this, because it's very similar to the trees that we see now. And then in his Origin of Life in 1859, he drew a better version.
And so what that tree is essentially saying is that we are sort of all derived from one common ancestor, and we evolved into separate branches. And so Carl Woese, some study in the sixties and seventies, came with this idea of, using actually DNA sequence to reconstruct the tree of life. And so this is what an example of one of those trees of life. So just to orientate you, if you're not familiar with this, that that little scale bar there is 0.1 chances so say that's 10% DNA, in the sequence between any two organisms on this tree.
So the closer the organisms are to each other on the tree, the more related they are. So he found that these bacteria, and then there's these archaea and eucarya. So to sort of orientate you, so here's us Homo Sapiens, here's the mushroom. So that gives you a sense of how much diversity there is on this tree, right? They're really close together. And if you actually look at it, all the things that we can see with the naked eye, all animals and plants, are sort of in this one little branch of the tree. So microbial life are all these branches that are highlighted here, is the vast diversity of what's on our planet.
So there's been in recent years, there has been huge advances in DNA sequencing and computers to sort of process all that data. And so this is just sort of a timeline to give you a sense of that, with new sequencing technologies. We've gotten more data and more cheaply. So when the first bacterial genome was sequenced in the early nineties, it took a huge amount of people, a lot of work, many years to do. And then when we first started doing metagenomics in natural samples, we were getting dozens of genomes a time, in the two thousands.
And recently now, due to new sequencing technologies, like this machine that's shown here, we can get thousands of genomes at a time, from an integration of samples. And this is really exciting just in my lifetime, in my scientific lifetime, there's been this huge change in things. And so my lab primarily works on samples that we collect from the deep sea. So I just want to show you, this is sampling that we did in 2018, using the Alvin submarine, the NSF, this was in the Gulf of California.
This is the same submarine that explored the Titanic, (background noise drowns out speaker) I show this because it gives you a sense of how much goes into sort of collecting these samples. It makes them really exciting to look at. So once you get down in the sub, and you sort of travel around a bit, you find these hydrothermal vents like this one here, and you can see there's this white hairy, and yellow hairy stuff, that's sort of growing all over the hydrothermal vent, this is all just thick microbial mats. I mean, you could see it with the naked eye.
So once it zooms in, you'll be able to see it better. So this is a really great place, I mean we're exploring entirely new microbial worlds to sort of understand the biodiversity there. So when we started doing this, with sort of metagenomics, this is what I like to refer to as sort of a Hubble moment where sort of the Hubble telescope went up to space and they collected these images and saw things that people hadn't seen before, essentially. That's essentially what we're doing, when we're sort of doing metagenomics on these really interesting environments the hydrothermal vents.
And what we did is we reconstructed a new tree of life using now not just an individual gene, but entire genomes, okay? And so here at the top you can see there's bacteria at the top and at the bottom there's eukaryotes (indistinct), and there's archaea over here. So the shape of the tree has really changed. Each one of the names on this tree is a phylum level. So very diverse, vastly different from each other. Anywhere there's a red dot on this tree, is a lineage that we have not grown in a laboratory.
So it's what we call uncultured. So you can see that there's, through this metagenomics, we've essentially doubled, tripled, the known diversity of life on the planet. And there's lots of great stories that I can tell you about throughout this tree. But one I'll focus on, that my lab is working on pretty intently, is looking at these organisms that we call Loki and Thor which you'll see down the bottom here. So there was this great quote from my colleague when this paper came out saying, "This is humbling, but holy cow, we know virtually nothing about the biology and most of the tree of life. And this is true, now we have genomes, but we don't really know a whole lot about the biology of these things.
So that's what we're sort of trying to understand. So some recent years ago, myself and my colleague, Thijs Ettema and several people in our labs, not just the two of us obviously, sort of set out to understand these groups that we call Loki and Thor. So the first group you'll see up on the right here is the hydrothermal vent, is called Loki's Castle.
The first group that was isolated from Loki's Castle, the genome was reconstructed from Loki's Castle, came from this site, so they called it Loki, so you'll see it down here in the tree, lokiarchaeum. And then we constructed genomes that were similar, so we called them Thor, we're continuing the Asgard analogy. Of course you could think about this as Marvel superheroes as my son would like to think, and there's, now we have Odin, and we have Heimdall.
What's really amazing is that when you put these in the tree of life, the eukaryotes branch from within these Asgards. You might say, well, what does that mean? What that means is that we, eukaryotes, plants, all eukaryotes animals, all evolved from these Asgards, right? So you can think of yourself as Asgardian, right? So that's my take home message today. This is really exciting because it's completely reshaped our understanding of the tree of life. And it has led to a lot of really interesting discoveries since this paper was published in 2017. So here's a different view of that essentially bacteria over here, archaea, and then us eukaryotes sort of evolving from the Asgards.
So that's all I have, this is my lab at Berkeley shown at the top here, and then my collaborators Thijs, and Jill Banfield and Andreas Teske. - Okay, thanks so much, Brett. That was really exciting, why Marine Microbiology has changed so much since I was a graduate student. That's just incredible. Now, let's see if we have some questions from the audience they've spend it home, I can see all kinds here. All right.
All right, Grace asks, when you reconstruct the DNA that you extract, are you looking more so at the proteins that the DNA creates and if not so what, if not so much what individual organisms are present, or are you able to group some DNA sequences together to determine that they are from the same organism. - Yeah, so we look at both at the DNA, and the proteins that's encoded in that DNA. And yeah, we sort of group. I think if I understand her question we do sort of group that DNA into larger pieces within a genome to understand what each of the individuals from the community has, yep. - All right, Lay asks, what kind of specialists beyond microbiologists do you collaborate with? So do you collaborate with others than microbiologists.
- Yeah, that's a great question. So I collaborate with biogeochemists who sort of try to understand how nutrients are cycled in the environment a lot. I also collaborate a lot with geologists, particularly those that are interested in the origin of eukaryotes and sort of that history in the rock record, we're collaborating with a lot now. Yeah, those are the main ones outside of other fields, yeah. - Okay, Elizabeth's asking, what's the most unique organism that you've found thus far. - Yeah, that's a great question.
We have a lot of what we call, it's a completely new phyla so, and there's actually a couple that we're working on now, they're just way out there, like, I mean, you talk about exploring other planets. I mean, the genome of some of these organisms are just so different, that it's really hard to even match protein at the protein level, what they are, and sort of even really put them in a tree and try and identify what they are. I mean, they're just so different. That to me is really exciting, just sort of trying to understand, like, it's exciting, but it's also really, really difficult 'cause you're sort of relying on what you know, to understand the unknown, and it becomes a challenge but it's really exciting in a lot of ways. So yeah, great question. - All right, here's a good one.
Grace is asking, if life on earth has been tripled basically, you found all these additional species in your expanded genetic tree. What does that mean for the current extinction event? Is this still the worst that we know of? - Yeah, it's hard for me, it's hard for a microbiologist to really think about extinction unfortunately, because microbes aren't preserved in the rock record very well, so the only microbes that we've looked at are the ones that we can see that are alive now, there's cases where DNAs preserves, say a few tens of thousands of years, in ice for instance, but it's really hard to know what the past extinction events have done to the diversity that we see now. I would say that the current sort of extinction that's going on in our planet now, isn't probably affecting the microbial community all that much 'cause they can live in so many different places that they can readily adapt to things, so they'll be around long after we're gone.
And we've probably planted microbes on Mars that are probably living just fine there where we've landed, so, yeah. - Okay, Zedekiah asks, can you talk more about how you incorporate data science into your work? - Yeah, I mean, yeah, so data science is, I mean, it's not all of what I do now, but it's, I would say, especially since the pandemic, we haven't been in a lab all that much, it's a huge part of it. So sort of like, I always tell people when they're interested in working in my lab, like, you'll do some field work, but you're not gonna be working in a lab, you'll be sitting in front of a computer a lot of the time and sort of processing data. Yeah, it's huge. And so if you're sort of starting out in your career, and you're interested in doing science, getting used to using computers is a very valuable thing to do for sure. - Okay, James asks, does DNA seem to branch at similar places along the tree or does it appear at random? - So it doesn't branch at similar periods so, now that we have sort of, when people were doing these trees with like one gene at a time, it was starting to look like everything's sort of branched at one point, but now that we have whole genomes and we're making more highly resolved trees, we can see that no, there clearly is like different times where things branch.
It's sort of hard to put times on those things, 'cause different organisms evolve at different rates. So it's hard to do that, but yeah, it's certainly not random. There are things that we see in trees that sort of match things that we've seen in the fossil records. So we know that there is sort of like common ancestors that occur more recently in time than did sort of deeper branches, they shared a much deeper in time, common ancestor, so yeah.
- Elizabeth is asking, what do you think we could do to increase interest in and focus on the deep sea rather than outer space? - Yeah, that's a good point. Yeah, I mean, one of the things that I always do in my talks is sort of say how, I mean, we know more, we have better maps of the surface of Mars and the moon than we do have our own deep sea. It's not to say we don't have maps of our deep sea, it's just that they're not very well resolved.
And so, it's hard. Yeah, and I mean, that's one of the exciting things to me is that we still have like really completely unknown worlds. I mean, we haven't even, I mean, you talk about just hydrothermal vents, we've probably explored like 10% of the vents that are out in our planet, so just a few years ago, there was these really new exciting hydrothermal vents that were discovered in the Gulf of California by some of my colleagues. And there's like these upside down glass pools that they found, they're essentially pools that are like upside down on the rock, and it's just sort of like, it's great. I mean it's exciting and think about what's out there that we haven't found yet.
- All right, Brett. Well, this next question sounds like it might've been better for Andrew, but Daniel is asking, how likely are the predictions of fishless oceans by 2050. - Andrew, are you there? Jump in.
- [Andrew] By 2020? - 2050. - [Andrew] Fishless oceans, I'm not as worried on that level. I think it's more likely that we're gonna have some species that are extinct and others that succeed. - Okay, so I think we need to wrap things up now.
So thank you, Andrew and Brett. And I'd like to thank all of you for joining us today for Texas Science Festival Talk on Diversity In a Changing Ocean. And I'd like to thank Andrew and Brett for their time, knowledge and experience.
There are several more Marine Science, and Biodiversity related events happening this week. So if you are interested in sea turtles, sea grass monitoring, or evolutionary biology, I hope you'll look into what's coming up at sciencefest.utexas.edu/schedule and sign up for more sessions between now and March 26th. As noted in the chat, you can also send questions to email@example.com. So thank you all for your interest in Texas Science. And we hope to see you virtually at more sessions soon.