Hi everyone!
I can finally call myself a Dr! (Except I don’t, because that’d be super weird). Passed my PhD defense last week and so I’m on to job hunting now.
But worry not, I also made some time to bring you the final episode for this series right on time! This time, we talk all things corals with a marine ecologist from Venezuela who’s worked in four countries across the globe, focuses on how to make reef ecosystems more resistant to climate change, and doesn’t shy away from speaking about her struggles to become a researcher. Her name is Adriana Humanes and she’s just such a rockstar.
Thanks everyone for supporting this project all the way - and special shout out to those who signed up from episode #1 and were there through all the teething problems as I was learning my way around microphones (sorry)!
I loved making this series. If you have liked listening to it and think there is worth in this project, I’d ask you to please do two things: one, talk to your friends about it and get them to listen to it too. And two, if you can, I could really use a coffee.
And if there’s anything you’d like to tell me, just reply to this email. I’d love to know your thoughts.
Thank you for your support!
Over and out,
Pablo
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Episode transcript
Uzbekistan. Today. Imagine a boat in a desert, stranded on the sand. No one thought it would dry up. But it did. The Aral Sea was once the fourth largest inland sea on Earth, bigger than Lake Victoria in Africa or Lake Michigan in America. But it quickly became a massive environmental disaster. Water from the two rivers feeding the Aral Sea was diverted for agriculture. The hustle and bustle of the local communities quietly disappeared as fishermen lost their main source of income. In just 40 years, the Aral Sea became one of the poorest regions in the country. There is now talk about restoring it, but there are technical and political challenges, and action is not yet following words.
We live on a blue planet. More than three billion people around the globe depend on marine and coastal biodiversity for a living. But you don’t have to live by the sea to care about it. Because seas are not just rocks and fish. There is a huge diversity of living organisms in them. There are actual forests, actual meadows that go on for miles. In fact, oceans make our planet one that we can breathe in. They produce most of the oxygen on Earth, and capture lots of the carbon that we release into the atmosphere. For this final episode, we will talk about a fascinating ecosystem - reefs. Because corals, these fascinating creatures, are basically immortal. Some have been around for millennia. But with a rising temperature and increasing levels of CO2 in the water, they are struggling. And yet. There is hope.
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So we are aware of it and we have the technology to decrease our emissions. So we just need to act. We have the solutions in our hands.
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Welcome to How To Make A Scientist! My name is Pablo Izquierdo, I am a neuroscientist and a science communicator and today I am joined by Adriana Humanes. She is a marine ecologist from Venezuela who studies coral reefs. Her aim is to figure out why some corals resist heat better than others, and to use this knowledge to help reefs cope with climate change. Enjoy!
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Adriana, what was the first time that you saw the sea?
Well, I really don't remember when was the first time that I went to see. I am from Venezuela, in the Caribbean, so the southern Caribbean. I lived in the capital city, Caracas, which is one hour away from the sea, so it's really common for people living in Caracas to go during the weekend to the sea. That's where I spent my weekend. So most probably it was like when I was a baby. So that's one of my first memories in life is is that, yeah.
Well, that clearly hooked you because now you work on corals.
I really, it's not something that I really wanted to do from early on. I was really keen to be a doctor. And I wasn't successful into getting into medicine school. And by the time it was like, one of the worst days of my life when I found out that I didn't get passing the test to get into medicine school. And I remember crying so much. I had studied so much for that test. And my father told me, well, maybe why don't you study biology is related to medicine, and then probably, you can then ask for an exchange to the medical school after the first year, which is something that you can do at the University where I studied. So that's how I enter in biology. During the first semester, I saw botany and I just fell in love of the plants. I really, really it was like, opening my eyes to this world. The next year, I saw the zoology lab. And then I had this professor she was she's a specialist in sponsors and in corals. And she was really enthusiastic. And the first lesson that I got from her about anthozoa, the group of the corals, I just fell in love with corals. And then I decided I didn't want to. And by that moment, I really have forgotten about medicine, I was totally hooked into the corals. And by the same time like when I finished school, I did my diving course. So at the same time that I was discovering all these new worlds, I was also diving. And so I think that was a good mixture to hook me into the coral world.
Yeah, know, good timing. It's funny, because this is the final episode. And we said just circles back to the first episode where Ephra was saying how he also loved botany lessons at university. That's, that's interesting. But corals are not plants. You said that but what are corals really because they do look a bit funny. And I remember that it took me forever as a kid to come to terms with the, well, with the idea that they are alive to start with, but they are no plans. What are they?
Yeah, and that's I think that's something that also fascinates me that it is really strange creatures that everybody looks at them. And it's really hard to decide what they are. Today we call them holobiont organism, because it's a group of many several organisms, what conforms the coral. So the animal has a translucent tissue. But inside that tissue are this microscopic algae that are the ones most responsible for giving them the color. So the color that we see, mostly is due to this algae when we find a dead coral at the beach, is the skeleton. On top of that skeleton is a tissue inside the tissue are the algae and the tissue secrets a lot of mucus. But tons of mucus, like you cannot imagine how much. And in that mucus, there's this whole world of microbiomes. The microbiome is confirmed by microbes, bacteria and fungi and everything together is what forms the coral colony.
Okay, so there's a lot more to them than we might think at first sight. We tend to think of coral reefs as one of the ecosystems most impacted by climate change. But why how does it affect them?
Well, I think like we're extremely lucky, and we are not the ones suffering in the first instance the impacts of climate change, but the corals are the ones suffering it because the ocean absorbs around 93% of the heat that is produced due to climate change. Okay?
Right, there's more water than land. And on top of that, the water is like disproportionally absorbing more.
Exactly, and as a as an effect, the temperature in the water is increasing, the rate of increase is, is faster, what we are seeing is faster in the water than in air. So in tropical areas the organisms that live in the water, they're living really close to their upper thermal tolerance. For instance, for us, our upper thermal tolerance, if our temperature increases to 38 or 39, if it goes to 40, we die. So corals are really, really, really close to that upper thermal temperature. In general, like in the tropics, that corals are around between 27 to 30 degrees, and at 31 degrees, they already start glitching. So a tiny increase in temperature in the sea occasionates a lot of stress in them, because then they're already living at this really close limit, upper thermal limit.
Yu said bleaching, do they lose their colour though?
Yeah. So when the temperature increases, symbiosis between the algae and the coral is broken, and the algae leaves or it's expelled from the coral. And since the tissue is transparent, then we see the skeleton, which is white. And that's why it's called bleaching. Because it's like the whole coral has been put in bleach. So it turns completely white.
And is that something that's happening now or a potential risk in the future?
So there have been five worldwide bleaching events. The first one was in 83’, massive bleaching events were recorded in many different localities around the world. Yes. Since 2015, there have been two massive bleaching events. And it is predicted that they're going to increase in intensity and in frequency. So before 1983 there's no records of massive bleaching events. And from that time that year, they started happening more frequently and more intense. Due to those last two massive bleaching events, the Great Barrier Reef lost half of his corals in those two years.
Wow. That's That's crazy. And it's so it's something that's happening now already as we speak. But why should we, you know, corals bleach and get stressed and die? Why should we care?
Well there is like coral reefs, they they give us a lot of services. And there's a lot of people depending on them. Around 5.5 billions of people depend directly from the services from coral reefs.
In what way?
Yes, and that is related to food security, coastal protection, fisheries, we also get a lot of compounds to produce medicines out of marine organisms. So 25%, that's of the marine fauna is associated to coral reefs. From those we have extracted around 20,000 molecules that are used for medicines for heart diseases for asthma, cancer. So there's plenty of resources that we use for our own health.
Right. So they're pretty useful things to preserve. According to your website, you work on, quote, assisted gene flow as a tool for restoration programs. But what does that mean what is your work about?
So at the moment, because we're losing coral reefs at such a fast rate, there's a huge necessity to see if, in the case that we get more bleaching events more frequently, that there are some active management actions that will need to be implemented in order to conserve reefs or corals in this potential tool of using assisted evolution where you just help evolution to act faster to adapt to the future conditions of the world due to climate change. And what that means is trying to find out when you have a bleaching event exactly as when right now with a pandemic, for instance, we know that there are some individuals that are more resistant to the virus, for instance, but we don't know why. So when there's a bleaching event, the same thing happens. There's some coral colonies that don't bleach, we're trying to understand why they don't bleach. And if we could understand why they don't bleach, is there a way that we could increase their frequency in the reef, so that reefs could be prepared to be more resistant to future heat waves that are going to impact them due to climate change. The next 10 years are going to be focused on restoring ecosystems. And if we're going to do that effort, why don't we restore them with individuals that we know are more tolerant to heat so that they have the chance to resist the future? So what we're doing is we are first identifying which are the colonies that are more resistant, and then we're crossing them.
Wait, how do corals reproduce anyway?
And that's the next question. So corals are animals. So they have sexual reproduction, they have two types of reproduction, they have asexual reproduction and sexual reproduction as sexually they can reproduce just by fragmentation. So for instance, there's a wave and they break into two, then these two pieces can grow independently and form two independent organisms, okay? That's asexual, and sexually they produce gametes. So the eggs and the sperm are released into the water column. And usually in a massive event, it's usually during summer. So once a year, during the night, they release all the gametes to the water column, and in the water column, they float to the surface. And in the surface, they get fertilized, and an embryo is developed. And this embryo will turn later into a larvae and carried away by the currents. And at some point, when the larvae is properly developed, it will change his buoyancy and go down. And there are certain chemical cues that these larvae can recognize. So when they detect this chemical cue produced by the algae, they will start crawling to the substrate and find a place to attach. And another way that they reproduce is by clonality, because they're clonal organisms. And that's how the colony is formed. They're all interconnected by the tissue. And they're all one identical to the next one. So they have the same genetic information, everything is the same. So what we're doing in a population that we're working with, so we're identifying the colonies that have high heat tolerance, and we're reproducing them in between them, and see if we're following them, their next generations colonies that we know that have been produced by parental colonies with high heat tolerance, and see if this heat tolerance is transmitted, if there's heritability of the heat tolerance, because as I mentioned before, the coral is a really complex animal conformed by many different things. So it could be that the heat tolerance is conferred by the genetic information of the animal. But it could also be that the algae is the one responsible, or it could be that the microbiome is the one conferring the heat tolerance to the to the whole colony. So we're studying the whole trying to see to disentangle, which is the factor that has more importance. And if this heat tolerance, it could be that is the combination of all of them. And it could be that it's not heritable, we don't know. So we're first trying to determine if they can inherit it. And if they can, could we use this information to produce the corals that are going to be used for restoration initiatives in degraded areas? So we're basically trying to answer the biological questions behind it in case it needs to be used.
Yeah, I mean, look, people listening to this can't see it, but I've been my mouth has been open for the last 10 minutes, like my jaws dropped to the floor. It's amazing how smart these things are and in terms of your work, is a bit like, I guess the selective breeding that people would do with, you know, crops or pets, I guess to get more cute looking kittens, except for you're looking at corals and you're trying to figure out. Like you said, have you managed, for example to resist heat? Is that?
Yeah, exactly. So we have done selective breeding for centuries, like we have done it with crops we have done it with tomatoes with corn, we have done it with cows, we have done it with dogs, cats, like name it. But that implies a lot of manipulation. It requires a lot of human intervention, sort of to say. So we are doing it like in the less invasive way, which is just with the same population. Let's try to see, which are the ones that have the highest heat tolerance in there. And that's trying to increase their frequency in that population without introducing genes from any other source.
Oh I see. Yeah, but it's amazing, isn't it? Because that means that science can not just help us report climate change, also it has helped us build the knowledge and provide the tools eventually to help us mitigate as well.
Yeah, that's true. And bleaching has been studied, like since in the first report was observed in the 83’. But then it was sort of forgotten. At the beginning it was only I think it was in 99’, that the first paper came saying that this massive bleaching events were caused by climate change. And it was a really controversial paper, like nobody believed it. People said like, no, no, that's not true. We are not producing this climate change. And we are not affecting the reefs in this way. So there was not that much research in trying to understand the mechanisms behind bleaching. But now that it's become like, as I have told you like in the last three years, or four years, we have lost half of the Great Barrier Reef, it really became like a mainstream research question at the moment.
Yeah, now in the situation that you are telling us about is just really dramatic. And frankly, I didn't know it was just so dramatic. And so it's so important that you do that sort of work.
So I just wanted to mention one more thing. So if climate change continues, with the current rate of increase, we are expecting around 90% of the reefs to be affected by massive bleaching events by 2030.
So in nine years time.
Yes. So we are in a really critical position at the moment, we really need to act, we really need to decrease our emissions. Otherwise, the reefs that we know today, that are going to be really different.
So that change will imply that they won't be able to support the fish that they do now, they won't be able to protect our beaches like they do now is that?
Exactly. So as like with climate change, we're also expecting more storms, more hurricanes, and the impact of those will increase if we don't have the reefs to protect us. So yeah, like, like, that's why at the moment, the coral reef communities really focus on trying to find management strategies on how to prepare and conserve reefs. But also like, there's no way we will be able to do anything if there's no climate action. So we are aware of it and we have the technology to decrease our emissions. So we just need to act. We have the solutions in our hands. So we need to keep pushing for it to happen.
I read as much as - I want to keep talking about your research -, I read that your journey into research hasn't been straightforward though. What was it like for you?
Yes, I think that life as a scientist is never gonna be easy. There's a lot of things that can influence how your career as a scientist develops. I think one is opportunities. And another one is luck. Another one is money. And another one is the network that you have. And I think those four things are really important. When I was born in Venezuela, Venezuela was in a really good position. At that moment we had the rise, or the development of the country due to the oil, and there was lots of money invested in education, and there was a lot of money into research. However, like during the last 20 years, as many might know, the situation in Venezuela at the moment is really bad economically and politically, we don't have a democracy anymore. And since 2005, the government decided that research was not important anymore. And the budget on education was really, really cut and of course, this meant a lot of lack of opportunities and it stopped the development of research in the country. So I finished my undergraduate and I tried to find a scholarship to do PhD. I was applying for a scholarship for five years. And I wasn't successful. Because I didn't have a paper. I hadn't published a paper by that time. And I wanted to go and study in Australia, I wanted to go to the Great Barrier Reef, I wanted to go dive into the Great Barrier Reef, so I was really decided that that was what I wanted to do. And I kept applying, and I, they told me, yeah, then you need to do a master's in here first.
Which is expensive, I am sure.
Which is extremely expensive. And there were no scholarship for that. And then I decided, no, I'm not gonna do that. And I did a master's in Venezuela. Then my supervisor during my master's, she did her PhD in Australia. And she was in that group that they discover the sexual reproduction of corals. So I thought, well, maybe I'm getting close. And getting close to that. Yeah, I finished my master's. And then I kept applying for scholarships, and nothing came. And then I decided, Okay, that's it. I need to work, I need money. I cannot continue as a student my whole life. And I decided to take the situation, the economic situation in Venezuela was really, really bad. I got a small scholarship to do a seven month study of photography in Spain. And then I thought, okay, maybe if I don't continue in research in academia search, I still have like a lot of my friends and everybody that I know, is studying the impacts of climate change in degradation, deforestation, on our environments. And I thought, well, that might be something interesting to document and I have a biology background, so I could explain things that I'm seeing through my images. So I decided maybe that was a new opportunity for myself. And my partner is also biologist and he also was really unfortunately, at the time of getting any jobs. And he also applied for a small scholarship in documentary filming. So we thought, well, maybe together we just develop. So we moved to Spain. And it was, I think, one month before moving, and I got a letter, an email, saying that I was granted a scholarship to do my PhD in Australia with the group that I wanted. So I couldn't believe it. But I had already, like, paid all my tickets, I have sold everything I have bought everything to go to Spain. So I asked for starting a semester later, and that gave me the opportunity to still go to Spain and study photography, and then go to Australia.
So you were able to do that anyways.
Yes, I was able to do that, then I went to Australia to do the PhD. So I think it's never going to be straight line, the path in science. And also, I've been really lucky that I got the support all the time of my partner. He has been really nice in supporting myself and following wherever I wanted to go to do this journey in science. So then I went back to Venezuela, and at that moment, Venezuela was going like through a terrible political crisis. They were no jobs opportunities at all. And I was there for one year. Both our passports were expired. And the government was not given passports anymore. So we got stopped in Venezuela for a year. It was a really hard time because I finally I was publishing I was, I had like all the tools to, like, propose hypotheses and write papers in English, which is not my mother tongue, and had a lot of ideas on research that I wanted to do. But I just couldn't do it, there was nowhere in Venezuela where I could get employed. And we didn't have any jobs for one year, and we weren't just stacked in there. And then finally, we got our passports. And we came to Europe, as my mom had left the country as well, like two years before, and she moved to Germany, and I was applying for positions. So during that year, I applied in total to 30 positions, postdocs, whatever you name it, whatever that is related to research, I did apply, technician positions. And it really felt like I was not gonna go anywhere. I was like, really, really starting to get depressed, because just living at my mom's house again, you know, like, in, you have already done all this trajectory, and then you're, again, stuck. But I got finally I have positive response in Newcastle University, for working in this project on assisted evolution. So we just moved immediately. And so it's been, it's been a great journey. But as I say, like, there's a lot of ups and downs. And sometimes you're really lucky. And I think like a lot of people say like, there's this said that “ey, if you really want it, or if you really try, you're gonna get it”. It's not always like that. There's many, many factors. And if you're not successful, it doesn't mean that you haven't tried enough. It also doesn't mean that it's that you're not worth. It's a hard journey. It's not an easy journey at all.
No, it's really and touched on the importance of luck and having the right network and having money, possibly speaking the right mother tongue. Having partners that can understand because we speak about how tough science career can be for scientists, but definitely for our parents as well. And so important to acknowledge that, do you feel like looking back in time, do you feel like you've succeeded?
Yes, yes, I think that I've succeeded. Throughout my journey, I have a lot of friends who didn't know the language, like we're not that fluent in English, for instance. And then all the doors were closed for them, or just needed to go working to support their family, like I didn't need to bring money to my home to for my mom and my mother and my sisters. But there's people that actually need to do that, because they're the only ones providing it to their family. So I was really lucky to, to have that opportunity. And I think I was able to succeed. But I have seen a lot of people failing, and not being able to succeed. And I think that, yes, my case is an example of success. And for my country, for sure, like people, my friends, they asked me all the time, they put me as a reference point. And if I see myself against other people from developing countries, like I see them as my as my reference point, and as a point of success.
Yeah, no, it's hard. And like you said, it's not like, you know, it's not, you're not gonna make it because you try hard. It's harder for some people than others. And it's nothing to do with you if you can't.
Yeah, exactly. And like, right now I have, like, the number of people that I know, that have started the journey with me as from the undergraduate until now, now that have stayed in academia. It's extremely, extremely low.
Yeah. And I think it's important that we discuss it really, because, you know, not everyone finds a place in academia and definitely there is world beyond academia anyways. So there's that. Adriana it's been really great chatting to you. But this is coming to an end. And sadly, this episode is the last of the series for now. You mentioned photography earlier, what would you put the spotlight like if you could have everyone in the world? Listen, if there was one message that you could throw out there, what would that be?
The solution is in our hands. Maybe not directly, but definitely in our politicians, like the people in the leadership positions are the ones who are gonna decide which way our work is going to go. And the way that you can influence who is deciding is by voting. So make informed vote, like know where they're standing in relation to climate action. That is the future for you and your children and your grandchildren. So just by that vote, no matter at what level that is gonna decide what work we have tomorrow.
All right, so think about the planet vote accordingly. Go vote people. Adriana Humanes, un placer. Muchisimas gracias.
Igual Pablo.
Thank you very much indeed.
Muchas gracias a ti, gracias por la invitación.
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That was it, folks. As ever, Thank you for listening, I hope you enjoyed this conversation and all the previous ones for what is worth. I certainly did. It’s been quite a journey from viruses through nuclear chemistry and neuroscience all the way to cancer and climate change. I loved - and I can’t stress this enough - I loved meeting and speaking to all of these people. It was a lot of work making this, I’ll be honest with you, more than I thought. And it’s been an eventful few months in my life personally, including moving houses and finishing my PhD and switching jobs. But this was my first solo project as a science communicator, which showed I’m sure, so thanks for bearing with me. I learned so much along the way and I am proud of what we’ve done together. I think it’s important that we acknowledge and celebrate that not everyone in science is a straight white dude. Some of us are gay, some of us are women, or non-binary. Some of us are Black. Some of us are immigrant and English is not our mother tongue. And it’s important that we talk about the science we love. But it’s just as important that we recognise the people doing it. That we talk about our stories and our fears and our hopes. Because that’s part of science, too. And I think we’ve done it.
You can still get on the newsletter at howtosci.substack.com, and I’ll give you a shout when new stuff comes along, or follow on Twitter at @HowToSci. And if you enjoyed this project so far, you can go to ko-fi.com/howtosci and get me a coffee. I’d really appreciate. The music for this episode was by Borrtex and Vasily Novikov, I’m Pablo Izquierdo, and this was How to Make a Scientist. ¡Adiós!