The Graduates is the talk show where we interview UC Berkeley graduates students about their work here on campus. Hosted by graduate students Ashley Smiley, Andrew Saintsing, and others, The Graduates airs every other Tuesday from 9am-9:30am.
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Andrew Saintsing: You'e tuned into 90.7 FM KALX Berkley. Im Andrew Saintsing. And this is The
Graduates, the interview talk show where we speak to UC Berkeley graduate students
about their work here on campus and around the world today, I'm joined by Sarah Guth,
from the Department of Integrative Biology. Welcome to the show, Sarah.
Sarah Guth: Thanks so much for having me. It's great to be here.
Saintsing: It's great to have you here. You've been away for a while, right? And you just got back
into the country.
Guth: Yeah, I was in Madagascar for eight months. I'm working with a team of researchers that
are studying bat-borne zoonoses.
Saintsing: What did you say?
Guth: Bat-borne zoonosis are diseases that are transmitted between animals and people like
the coronavirus that we're currently experiencing.
Saintsing: You're not studying coronavirus though.
Guth: I'm not specifically no, though the bats we study in Madagascar, do have beta
coronaviruses we think, but we haven’t isolated them. So we don't know the exact,
exact type of beta coronavirus. It's probably not COVID-19 but it may be something
Saintsing: So beta coronavirus, that's a, that's a big group of coronaviruses that there's a lot of
differences among beta coronaviruses?
Guth: There is. Yeah. So there's four general groups of Coronaviruses. There’re the beta
coronaviruses, the alpha coronaviruses, then I think delta and gamma. Um, I'm not
exactly sure, but, uh, COVID-19 is a beta coronavirus. The beta and alpha coronaviruses
are typically found in rodents and bats. So it's a large group of coronaviruses though. I
I've read that coronaviruses are very diverse, so you can have a very diverse set of beta
coronaviruses in a particular bat species, which is part of the reason why they're so
susceptible to recombination and spilling over into not full hosts like humans.
Saintsing: And that's just because there's so many different kinds of coronaviruses living in the
same bat that they can just get close to each other and share information.
Guth: That's yeah. That's my understanding
Saintsing: You're not really studying the coronaviruses though. Are you studying a particular virus
that the bats have?
Guth: So, our group has historically looked at serological evidence of filoviruses and
Saintsing: Serological evidence being blood?
Guth: Yeah. Taking blood samples and looking for antibodies to look at past exposure to
specific pathogens or specific groups of pathogens, because oftentimes there can be
cross-reactivity between pathogens in our particular group. So you can't, we can't say,
as of up to this point, we haven't been able to isolate specific pathogens in the bats, but
we know that there has been exposure to pathogens in the group known as filo viruses.
So a Ebola is in the group of filoviruses. So yeah, my dissertation is not going to focus
specifically on Corona viruses, more focused on filo viruses and henipaviruses.
Saintsing: What are henipaviruses?
Guth: So henipaviruses, some examples you may have heard of. So Nipah virus is, and these
are not viruses that I've ever come to the US but Nipah spills over from bats to pigs, to
humans in Malaysia and from bats to humans in Bangladesh. And this happens quite
regularly in Bangladesh because, um, it's shed in bat urine and bats, well bat urine gets
into date palm sap and humans consume that sap. And so it happens actually annually.
Saintsing: Like pretty bad or?
Guth: Uh, yeah, it does. It is, um, the case fatality rate. I'm not sure exactly what it is, but it's,
it's higher than COVID-19. I think it's almost as, or around as virulent as the SARS
epidemic we saw in the early 2000s, but yeah, I'm not sure exactly what the case fatality
Saintsing: Is it, it's been known for a while, or like when was the first time they recorded cases of it
Guth: Uh, it's a goo
Mattina Alonge:Hello. Hello, you're listening to 90.7 KALX Berkeley. I'm Mattina, and this is The Graduates an interview style show where we get a glimpse into the work and experiences of UC Berkeley graduate students. Today, I'm sitting here with Kwasi Wrensford, a PhD student in the Department of Integrative Biology. Welcome, Kwasi.
Kwasi Wrensford:Hi, Mattina, thanks for having me.
Alonge:You describe yourself as a behavioral ecologist. And I'm wondering if you can explain a little about what that actually means,
Wrensford:Right. Uh, that's a great question. So a behavioral ecologists, we sort of describe ourselves. So we focus on animal behavior kind of, um, as the big general guiding principle, but what kind of makes it behavioral ecology is we're interested in animal behavior in the larger context of an animal's environment and its interactions with, with that environment and with other animals in the environment. So a lot of behavioral ecologists, um, tend to focus a lot on things like mating behavior, um, how they find and acquire food and how they might compete with other species or with, um, individuals within their own species. So that's kind of a short version of what's a behavioral ecologist is.
Alonge:Okay. Basically how an animal interacts with both living and nonliving aspects of this world. Yeah. Um, is there one of those things that's more important?
Wrensford:That's, that's a really good question. Um, and I guess personally, I don't know if I could make an argument for one or the other. I think it's all integrated, you know, I think these aren't mutually exclusive things, right. So one drives the other, drives the other, right. So, uh, it just kind of often depends on what people are more interested in or what they kind of what their little favorite aspect of animal behavior is. Um, but me personally, I don't think they're, um, one's more important than the other.
Alonge:Okay. On that topic. What got you really excited about animal behavior?
Wrensford:Yeah. So I've always loved animals. I was kind of the, I was always the weird kid who was always into, uh, into animal books and I loved going to the zoo. And so I always liked animals just in general, but I guess what got me interested in animal behavior is like an actual research topic was, uh, actually in my undergraduate years, I got a, I got a special grant or scholarship through the National Science Foundation that they give to undergraduate students to go out and do a research project with a lab somewhere in the country. And so I got a grant to go out to this amazing field station in Colorado, the Rocky Mountain Biological Lab. And there, I got to work with, uh, a professor Daniel Blumstein who studied the behavior of these awesome animals, yellow-bellied marmots, they're very cute. Um, you know, if you've ever seen, like if you ever been out into the mountains of California, they're up there, or if you're back East, woodchucks are very similar, groundhogs.
Wrensford:Just very large fat squirrels. But this project is really cool because it was like a, it's a long-term study. So they've been studying the same population of marmots for the past, uh, since the sixties. Um, yeah. So my old advisor, Dan, Dan, he was actually the second PI to head this project. And so yeah, I got to go out there, trap the marmots, observe them and sort of work on all aspects of the project. And that really is what got me thinking that, and, you know, behavioral research is a thing that I could actually do, you know, actually just kind of watch animals in their own environment and start with, from my science, from there, you know, that's a really cool feeling. There's immense value in, um, captive laboratory animal research. And, you know, we've learned so much from the models we have, but you know, you can't replace actually, I'm seeing an animal in its natural habitat when y
Andrew Saintsing:You're tuned into 90.7 FM KALX, Berkeley I'm Andrew Saintsing and this is The Graduates, the interview talk show where we speak to UC Berkeley graduate students about their work here on campus and around the world today, I'm joined by Eli Mehlferber from the Department of Integrative Biology. Welcome to the show, Eli.
Eli Mehlferber:Hey Andrew. Thanks for having me.
Saintsing:Great to have you here. How are you doing?
Mehlferber:Pretty good. You know, all things considering right now.
Saintsing:So, Eli, I hear you study tomatoes?
Mehlferber:Sort of, um, I studied the bacteria that live on tomatoes, specifically the bacteria that live on the, uh, leaf surfaces.
Saintsing:Okay. So you study bacteria on the leaves of tomatoes.
Mehlferber:Yeah, I'm looking at the, uh, host microbiome interactions. So trying to understand how the bacteria living on an organism can provide different functions for it. So in this case, it's how bacteria that live on the leaves of tomatoes to protect them from disease. But you could also apply it to like the bacterial living in the guts of you or I.
Saintsing:Oh, cool. Yeah. I hear about microbiomes all the time. You've got to eat yogurt, right?
Mehlferber:Yeah. Get the active cultures.
Saintsing:Right, right, right. So wait, like plants need bacteria to get rid of diseases. So plants are like, like what kind of diseases are plants fighting?
Mehlferber:Well, plants can get all sorts of diseases. Uh, viruses, bacteria, uh, fundal pathogens, all of that stuff. Uh, I focused mostly on bacterial. Uh, so I study a lot of different bacteria, but the, uh, model pathogen we use is the bacteria Pseudomonas syringae. So that causes bacterial spec.
Saintsing:What's bacterial spec?
Mehlferber:So if you've ever seen a tomato or a tomato leaf that has a bunch of tiny little black dots on it, that's bacterial spec.
Saintsing:What does it do? Is it, does it kill the plant? Yeah.
Mehlferber:So it's a, uh, yeah, it'll infect the plant and eventually kill it. Uh, most tomatoes that we grow for, like food production are resistant to it, which is good, but it is a breaking out in some new agricultural cultivars. So, kiwis, for example, right now are super, super sensitive to a certain strain of Pseudomonas syringae that's like wiping them out.
Saintsing:Okay. Wait, so people have engineered or like bred tomatoes to be resistant to those bacteria?
Mehlferber:Yeah. So most cultivars that you would have out of in a field are resistant to it, but we studied the more sensitive ones in the lab.
Saintsing:I got you. And the, and so kiwis are having a breakout, so they're not resistant to it, but they generally don't encounter it.
Mehlferber:Uh, so previously they hadn't. It usually infects leaf tissue, but in kiwis it's, uh, the bacteria is actually mutated. And so now it affects the wooden tissue. So it causes, uh cankers. I can't remember the exact name of the disease. I think it was like a bleeding canker disease. Yeah. So it causes this gross red sap to like leak out of the trunk of the kiwi. So it looks kind of like it's bleeding and it'll kill the whole tree.
Saintsing:Yeah. Gross. Wait, does this bacteria, I guess, like, can you even get a fruit from it if it has, if it's infected?
Mehlferber:Uh, I think it sort of depends on when it was infected and how extensive it is, but it definitely does impact yield.
Saintsing:I see. So you study how these plants are using microbiomes that would prevent these bacteria from infecting them basically.
Mehlferber:Yeah. Sort of, um, I focus a little bit more on the microbiome side. So there are two ways that a plant can be protected from a pathogen, a bacterial pathogen. Um, one of them is through the plant immune system and that can also be triggered by the bacteria living on them. So you can have a good bacteria. Let's just call them th
Andrew Saintsing: Hi, you're tuned into 90.7 FM KALX Berkeley. I am Andrew Saintsing. And this is The Graduates, the interview talk show where we speak to UC Berkeley graduate students about their work here on campus and around the world. Today, I'm joined by Elisa Visher from the Department of Integrative Biology. Welcome to the show Elisa. It's great to have you here. So Elisa, you study viruses, is that correct?
Elisa Visher:Yes, I do. And I kind of always backed back from that statement because while I study viruses, I think a lot of times what people hear when I say that I study viruses is that I study kind of the really important human pathogens that you hear about in the news today. So things like Ebola or the flu or HIV, and I did actually study flu for a while, but right now, what I'm really focusing on is kind of generalizable theories about how infectious diseases and viruses evolve, and also how they shape broader ecological and evolutionary patterns that we see across the globe today.
Saintsing:Okay, interesting. So how do viruses actually shape ecological and environmental patterns that we see?
Visher:So there's a couple of key kind of important observations that viruses and infectious diseases more broadly are implicated in. So a lot of the things that infectious diseases seem to explain, actually have to do with diversity. And so some things that we think that infectious diseases affect are how much genetic diversity is maintained within populations. Um, so there's one theory called the red queen hypothesis. That explains why plants and animals were selected to have sexual reproduction and then infectious diseases and parasites and pests more generally have also been implicated in species diversity patterns. So one of the big patterns that we see across the globe is that tropical regions are a lot, have a lot more species than temperate regions. And there's a lot of possible drivers for that pattern. But one of the possible hypotheses is that these infectious diseases or more generally biotic interactions. So that's just any sort of interaction between living things may be causing there to be more species in the tropics.
Saintsing:Okay. So you mentioned the Red Queen hypothesis. What is, what is that, why is it called that?
Visher:So the Red Queen hypothesis actually comes from Lewis Carroll's Alison Wonderland, and there's this one quote that's in all of the red queen hypothesis papers. And it says it takes all of the running. You can do just to stay in the same place. So that name was the Red Queen hypothesis. That name was actually originally used to describe some patterns in macro evolution. So macro evolution is the study of evolution over millions and millions of years. So pass the dinosaurs through the fish through when things were just single celled organisms, kind of macro evolution is concerned with those patterns, right? And so the Red Queen hypothesis, that name was originally used to try to explain why species went extinct. But later on in the 1980s, the name was kind of co-opted by people studying infectious diseases and parasites to explain why organisms or species more generally have evolved sexual reproduction rather than just clonal reproduction
Saintsing:And clonal reproduction is asexual.
Visher:Yeah. So clonal reproduction is just that you make an exact copy of yourself. And so all your offspring are just exactly you. So when we think about natural selection, kind of one of the key tenants is that the point of natural selection kind of what it works on is your reproductive fitness. So your ability to get your genes into the next generation.
Saintsing:And so ideally you would just want exactly your genes.
Visher:Exactly. So if you're clinical, you're getting a hundred percent of your genes into the next generation, but if you're a sec, if you're sexually reproducing, then only 50% of
Erik Sathe:You're tuned in to 90.7 FM KALX Berkeley. My name is Erik Sathe and this is The Graduates, the interview talk show where we talk to UC graduate students about their work here on campus and around the world today, I'm joined by Nick Spano from the department of integrative biology, who studies conservation, paleo biology. How's it going, Nick?
Nick Spano:Pretty great. Erik.
Sathe:Good. I'm glad to hear it. So how did you first get into research?
Spano:Yeah, I first got into research through really just keeping my nose to the grindstone with classes and really getting involved in that and really finding that as kind of a fun pursuit to learn these things in classes. And what happened was I took an earth history class during undergrad, and I had talked with the professor and I told him, Hey, I am interested in paleo stuff. And this has been earth history class. Are there any opportunities for me to do something like that? And he said, sure, yeah, I run a research facility here on campus. You want to come check it out sometime? And I said, yeah, that sounds great. And so he invited me over to check out this facility and the facility itself is called the large lakes in observatory. And it is a institution at the university of Minnesota Duluth, which is right on the Western tip of Lake superior and being right on the tip of Lake superior. The idea is, okay, this is the biggest Lake in the world. We can effectively treat it as an ocean. And so the people who work there are mainly trained in oceanography, study things about ocean physics, ocean chemistry, plankton, and so forth. But his background was in paleoclimatology and being able to tell how climate has changed through time through sediment records that people have pulled up from the ocean floor. And so he just showed me around this building and at the end of it, he said, yeah, how does it look? How does it sound? I said, yeah, this is all really cool. And he said, great, do you want a job? I said, yes, please. And yeah, that was a really fortunate start for how I got into research. Yeah. It sounds very organic. And it was kind of following your own interests and just sort of happening across someone who could provide an opportunity for you. Yeah. So what can we learn about the climate through paleontology? Yeah, that is a really great question. So I would say the main thing that we can learn about climate through paleontology is a sense of scale about how bad climate change is today. And so, by saying bad, I mean, what is the rate at which climate change is happening? It's speed, it's magnitude. And so there are things for example, where we can look at, okay, climate is warming today has climate warmed in the past. And by looking at the paleontological record, we can say, yes, climate has warmed in the past and we can get into the question of, okay, how quickly did things warm in the past and how quickly are things warming today and how does that compare? And there are a lot of very stark things that pop out from that. And so, for example, when we look at a very extreme warming event that has occurred in earth's history that we see recorded in the history of life. At that time, the paleontological record, it is an event called the Paleocene Eocene, thermal maximum. And this happened about 55 million years ago. And what we see happening then is a change to primates at the time, living in places where they'd never lived before to a lot of species in the ocean becoming extinct. And the rate of warming of that event was something that is the highest we've seen in the past, at least 65 million years. And for the carbon dioxide that was put into the atmosphere and caused a warming at that time, the rate at which that carbon dioxide increase causing that warming compared to the rate of carbon dioxide increase we're seeing right now is tenfold. So we are pumping out CO2 at
Andrew Saintsing: Hi, you're tuned into 90.7 FM KALX Berkeley. I'm Andrew Saintsing. And this is
The Graduates, the interview talk show where we speak to UC Berkeley graduate
students about their work here on campus and around the world. Today, I'm joined by
Mattina Alonge from the Department of Integrative Biology and also a fellow host of
Mattina Alonge: Hey, Andrew.
Saintsing: It's so great to have you here, Mattina. We're really excited to hear a couple more
interviews produced by you this semester.
Alonge: That's the right way to put that.
Saintsing: So stay tuned. So Mattina, how are you doing?
Alonge: I'm doing good. I'm great.
Saintsing: Cool, cool. Unlike all of the other hosts, current hosts of the graduates, you do not study biomechanics.
Alonge: That's true. Yeah. I’m the one stand-alone non-biomechanics nerd.
Saintsing: What do you study? So, I would also say I'm a physiologist. So do you, would you call
yourself a physiologist or?
Alonge: Why, why do we have to find a label?
Saintsing: Yeah, that's a, that's a good point. Good point. Science is so interdisciplinary, right? We
don't need to be labeled and sequestered.
Alonge: I think that' a really hard question and people ask it a lot of anyone who is involved in
science, but I think I would call myself an eco-physiologist.
Saintsing: Okay, cool. So you'e interested in how organisms are relating to their environment and
how energy is moving. Not just through an organism, but through the ecosystem as a
Alonge: Yeah, exactly.
Saintsing: What, what do you study in that? You, you look at birds?
Alonge: And bats, yeah. Flying things. I love things that fly. Yeah. So I guess in general, my
questions seem to centralize around this idea that every animal is juggling a lot of
energetic demands, just like people. So we have to make conscious and strategic
decisions about what we choose to prioritize at any moment in time and animals do the
same thing. And a lot of that is impacted by the particular environment that they're in.
So in terms of birds and bats, they're interesting because they fly obviously, but flight is
a pretty costly activity, especially for mammals who also have added demands in terms
of reproductive activities like pregnancy and lactation, which are also really
Saintsing: What do you mean? Birds have to create their offspring too. Right? I mean, but I guess
it's all that they, they make an egg and then they just kind of are done with it.
Alonge: Yeah. I mean, you shouldn't like diss on bird parents. They still put a lot of energy into
raising babies, but it's a little different, they don't have to carry around this extra weight
and, you know, shuttle a lot of internal resources to their offspring and sort of like an
investment that they make in this one little package. And then they drop it off and take
care of the package for a while, but they don't have to carry it around and feed it
constantly until it patches, I guess. But yeah.
Saintsing: Okay. So you're looking at how they navigate those energetic demands and you have a,
or your work is kind of focused on the reproductive aspect of their biology?
Alonge: Yeah, exactly. Yeah. I guess because reproduction generally is a pretty costly activity for
any animal, whether it's birds bats or any other species. So, and it's also really
important, right. For the success of that species. Like every animal cares about
maximizing his fitness and reproduction is a key part of that. So, um, I think also if, you
know, if people are interested in conservation and things like that, um, understanding
how animals might prioritize reproduction or not prioritize reproduction at any moment
in time can be really important with the changing environment. Right.
Saintsing: Yeah. Okay. And so how do you study these questions? You're kind of looking at