Polymath World Channel

GENE EDITING AND TERRAFORMING MARS

Dr Erika DeBenedictus is CEO of Pioneer Labs. She is a computational physicist and synthetic biologist working at the intersection of space science and the life sciences. She studied at Caltech before moving to MIT and did her postdoc under 2024 Nobel Laureate David Baker. She also trained at NASA's Jet Propulsion Laboratory. At Pioneer Labs they use several methods, including CRISPR and other forms of gene editing, to engineer microbes such as cyanobacteria to help make Mars more hospitable to earth life. The Great Oxidation event saw cyanobacteria transform earth's atmosphere into a world inhabitable for us and the same could happen on Mars but much faster. Mars was once very earth like - could it be brought back to its life-supporting state?

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Polymath World (00:01.192)
Hello and welcome to the Polymath World Channel and we're digging into maybe my favorite subject, which is the meeting point of space science and the life sciences. So we are looking at Mars, we're looking at terraforming and we're looking at microbes and how we could generate a second space where life could flourish. And I'm joined by an expert on this, someone who I heard speak at the Mars Society, an incredible scientist who's

turning what a lot of people see as fantasy and science fiction into a reality. There's a really, really engaging, vibrant community looking at Mars and it's wonderful to dig into this for the benefit of all of you. I'm joined by Dr. Erika de Benedictus today from Pioneer Labs. Thanks so much for joining me today.

Erika (00:48.364)
Yeah, thanks for having me. As you say, I have one of the coolest jobs in the world. It gets the job of any good scientist to turn sci-fi into sort of sci-fact.

Polymath World (00:59.496)
Absolutely, and we had Dr. Tiffany Vora on here who I know you know very well, another brilliant scientist in the Mars Society community. And I can't wait to dig into what your work is, but as we often do on this, I'd like to start with your story. So when you were really young, did you know you wanted to work in the life sciences?

Erika (01:21.262)
Um, no, very much not. I, uh, I actually, I s- I sort of caught the science bug because I was forced to do science fair projects in middle school and-

for a long time, I didn't work on life science at all. had, I had kind of no idea and kind of no access to like lab facilities or anything like that where I could do biology work. So my, the very, the very first science fair project I did that like really caught my fancy was I had visited my, grandma's house in Ohio. grew up in California and New Mexico, both places that don't have like a lot of snow. And I'd, I'd seen a real snowflake, like a big lacy snowflake. And I

whole project on simulating how snowflakes form. So I did like a cellular automata thing with like a hexagonal grid and it made these cool lacy patterns. And yeah, I did I did a ton of like, sort of physics simulation stuff. It was like really easy and accessible. I was a kid with a laptop. And so that was a really easy entry point. You can do like very cool science projects with very simple math and physics if what you're studying is something like snowflakes.

or like the solar system in orbits and things like that.

Polymath World (02:37.509)
And when did space science really take hold? Was that later or was that from the very beginning?

Erika (02:43.475)
space science or life science.

Polymath World (02:46.198)
space science.

Erika (02:47.662)
Space science, yeah, I...

was very lucky to get to go to this wonderful astronomy camp in high school and we it was all you know it was so cool it was like very romantic like the lifestyle of being astronomer and astronomer especially at the time where it's like you know you stay up late and you go to the dome and you have a you know cup of hot chocolate and you watch the stars and then in the day you get to go do some math to like compute the orbits which is like also cool so

So that was kind of where that came from. found it so fascinating. Like there was something mysterious and compelling about being a scientist and being able to understand these deep things about how the universe works just by taking pictures of the sky. And I really liked that as a...

and aesthetic and like a delightful thing to do. So that was where the sort of fascination with space science came from was, you know, encountering some like very good mentors at this astronomy camp. And also it was just very accessible. Again, you know, you can, yeah, I did a bunch of work on a bunch of science fair projects on doing low energy orbit planning. like, how do you, you can actually like,

plan paths through our solar system that require way less fuel if you are really clever with like the movement of the other planets and sort of have the Sun and Jupiter always like pulling you in the right direction by just like timing it correctly they take forever so the orbits are rarely actually used but again it was this

Erika (04:38.636)
really interesting and very accessible area of science to someone who, you know, I like had good mentors in maybe teaching me how to program, but I had no access to like lab facilities or anything like that. And so that was, that was what I could play around with at home.

Polymath World (04:56.872)
Mars has its own special particular draw. Can you remember any moment really when Mars came on your radar as something of great interest?

Erika (05:07.32)
I think Mars is actually a much more recent fascination. It's a fascination because...

kind of during COVID I had, gone through this whole, I mean, it had been a decade since I had really thought about space science and I had gone all the way into life science. And during COVID I was like, wow, I should like check in on that, on that discipline that I like haven't thought about in a long time. And I, so many things had changed. I mean, the private space industry has, enormously contributed now to

progress in space science. And that has, I think, caused the whole field to come alive and become really interested in like new people with new ideas and what they can offer. And yet, space science today is still like...

still very similar to its sort of like mechanical engineering, electrical engineering roots of like the core competency is like building spacecraft that can go places and take measurements. And that whole mindset is very different than biology research where you kind of never know what will happen. And I wanted to understand like, why don't we use biology in space?

sort of mess around with it, but it's not like a mission critical piece of space science, like mission architecture. And so I started thinking about like where in the solar system could we actually have life, like at scale. And I did a bunch of math. have this gigantic spreadsheet in my Google drive that computed the

Erika (06:50.452)
upper bound on how much biomass you could make on different objects in our solar system. So if you took like all of the atoms like on the moon that are carbon, nitrogen, hydrogen, oxygen, and then like the trace, the trace elements in biology, how much biology could you make? And it turns out that on earth you can make a lot.

And on Mars, can make a lot. And everywhere else, there's some reason why you just can't have that much biology. You couldn't really have a planetary scale biosphere on the moon because there's just not enough nitrogen and there's not enough water. And same with Venus. There's not enough water on Venus. It all evaporated. It got blown away into space by solar wind. There's not enough water left.

And so Mars is this fascinating place that is like so close to being so friendly to life and yet.

with the little tiny problem that it's way too cold. But aside from that, it has all the right components to be a really friendly place. And this is what the fascination is with Mars, that it has the potential to be actually an incredibly welcoming place for humans to live and have a whole civilization. And you could bring Mars alive with, if only it was just warmer. So it's so close and yet so far.

Polymath World (08:01.298)
Yes.

Erika (08:18.224)
sort of thing.

Polymath World (08:19.364)
Yeah, tied into all this is the fascination of did it used to have life? What was Mars like kind of at the time of the early Earth? And could it have life in the future? We'll get on to that. I'm just curious as to where you went to study and what was it you particularly studied and what was the pathway?

Erika (08:41.666)
Hmm. Yeah, I went to undergrad at Caltech, where I got to do some research projects at NASA JPL, which is sort of like a right down the street. So that was amazing. And while I was at Caltech,

Polymath World (08:52.584)
I'm

Erika (08:59.726)
Kind of two things happened that pushed me toward life science. One of them was that I had a friend who was like, Erica, like you've been doing all this like simulation stuff. Like, why don't you try simulating proteins rather than simulating the solar system? And so I went and I did an internship at D.E. Shaw Research, which is this, it's this research org that built

at the time, like some of the most sophisticated supercomputers were like doing simulations of biological systems. And I did an internship there and became fascinated just with like kind of how hard it was actually to like simulate things correctly in life science.

Polymath World (09:42.896)
Yes.

Erika (09:43.875)
The solar system is mostly vacuum, so it's easy to simulate. Cells are full of God knows what, and so they're very hard to simulate. And so I became really interested in this discipline where the tools I knew actually didn't work as well. And so I was like, my God, what if I'm wrong? Like, what if we can't simulate this? What then?

Polymath World (09:50.407)
Mm.

Erika (10:04.204)
And I also at Caltech, like I was finally somewhere that there were real lab facilities. So I, I got to do like a little bit of biology research in undergrad. was working with someone in the Elowitz lab and they were, they were like, okay, we're gonna.

Polymath World (10:14.696)
you

Erika (10:22.072)
We're gonna take a cell and we're gonna tag all of the mRNA transcripts of this gene with like pink, and then we'll look at it under the microscope. And I was like, no way, are you able to tag individual mRNA transcripts in the cell and image them? And then actually like that is actually how it works. And it was just totally mind blowing. So I did like a little bit of that in undergrad. And then time came for, you know,

Polymath World (10:39.687)
Yeah.

Erika (10:49.462)
what do you do after undergrad? I took a gap year and did a bunch of travel and thought very hard about what I wanted to do and decided.

decided to go into biology. So I went to biological engineering department, MIT for grad school, which my parents told me I was crazy because I had also gotten into EECS, electrical engineering and computer science. And they were like, why would you turn down that degree? And I'm like, but I want to do biology. Like I want the next adventure. And so, and so yeah, I did a totally, totally.

I did a bunch of laboratory automation and things like that in grad school, but I was very dedicated to not be pigeonholed as the person who could program. And so I actually did a bunch of wet lab work and really learned how to do experimental biology.

Polymath World (11:45.223)
Amazing. That's such a cool journey and I absolutely love it. One thing that came up there, you talked about the role of the snowflake in triggering things at the beginning. I find your biology really beautiful and you say, yes, nature is beautiful, but I mean molecular biology, structural biology, every macromolecule being a different shape, like the way snowflakes are different shapes. I kind of find that structural biology is a bit like

nature's biology snowflakes in that beautiful way.

Erika (12:18.292)
I, yeah, I still, I still find this so fascinating and paradoxical. and, and this brings us to the very limits of like what we can do with bioengineering today. Like we're still.

at the very infancy of being able to engineer like macro scale structures by engineering a single protein or something on the micro scale. It's still like incredibly hard, you know, despite, AI is solving all the things. No, AI has not solved this thing yet, right? Like it's actually still really difficult.

Polymath World (12:45.192)
Yeah.

Erika (12:55.642)
and that is one of the great mysteries of like, like I love these parts of science where you have this sense of you're like get dizzy because of the senses of scale that you're traversing. You often get that sense in astronomy where you're imagining distances that are like so enormous. And I think you get that sense in biology too, where you're like, okay, well can make like a single gene edit to this one gene in this organism, but that organism will make a biofilm that's like as big as my head.

right? And so the sense of scale is so enormous that you can sort of traverse in one single experiment in biology.

Polymath World (13:34.833)
Yes, yeah, it feels, yes, it's in its infancy, but it's incredibly exciting being at the frontier of this right now. Like at this time, Tiffany Vora said this, biology has never been hotter than it is right now. And 100%, I could have said that at the same time and we'd have been finishing each other's sentence. And I say that students a lot, biology has never been hotter than it is right now. You mentioned the...

Erika (13:42.36)
Mm-hmm.

Polymath World (14:03.964)
the wet lab experience and just how cool it was making those, highlighting that pink. I think a lot of students do wet lab, basic wet lab experiments in high school and think, this is kind of boring. I wouldn't want to do this for a job. And I kind of want to say, no, just wait until you're at uni. You get to do so much cool stuff that's going to blow your mind.

Erika (14:28.858)
I'd also say, so the undergrad research experience I had in biology, I was not good at it. So I actually, wrote, I wrote a whole essay for some other class about how, how like actually funny to me it was, like actually how bad I was at that particular type of experimental biology. I was working with stem cells, which are some of just the trickiest to culture.

Polymath World (14:35.816)
Bye.

Erika (14:57.14)
it's like the hardest type of mammalian tissue culture because if you don't treat the stem cells just right they'll differentiate and so I would always come into lab and my stem cells had differentiated into neurons again I was like now I have to start over and then it's another week or whatever and so like I was not good at it when I tried it the first time and it took me a few tries to find a type of experimental biology that

I both had enough personal skill and maturity to do well and also the matched.

the speed that I like to operate at. And this is like why I work a lot with microbes because the iteration cycle of doing microbe experiments is just a little bit faster. It like tends to work well for sort of how fast I like to think and how fast I like to see results. And other people are different. Some people prefer working with mammalian cells or mice, which are sort of slower. Some people like working with plants, which are really slow. But I think it took, it like took some trial and error for me to find

Polymath World (15:59.241)
Erika (16:03.344)
a particular type of experimental biology that actually like I enjoyed in addition to like thinking that it was conceptually cool, which of course I think it's all cool. But it's different to like find something you like doing day to day.

Polymath World (16:19.362)
Yeah, thank you for sharing that. I'm really grateful that you said that. mean, I, when I went back to Cambridge as a post-grad, I nearly quit biology because I had not been in the lab for a while because of COVID. You know, we weren't allowed in the lab for, it was years before I was back in because I'd moved on to computational stuff. And I nearly quit because I thought I'm just terrible at this. I'm the worst person in the class.

Erika (16:34.222)
Yeah. my gosh. Yeah.

Polymath World (16:48.976)
And it wasn't the professors actually, it was some fellow students and some post-docs that sort of gave me some encouragement and I thought, you know what, this is worth it, stick it out. It's been a few years, so don't worry. But now I'm really glad you said that. Could you tell us about Pioneer Labs, but how it started and what you're doing? I'm really excited to get into this.

Erika (17:09.838)
Yeah, I, after COVID, I really wanted to work on this intersection of biology and space science. I...

I just, there's so much potential for biotech to improve our ability to go to space. And I just think it's like so understudied relative to the impact it can have. And so I tried working on this in an academic setting. So I ran a lab, academic lab in the UK at the Francis Crick Institute, which was a great experience, but I think.

Polymath World (17:31.644)
Yes.

Erika (17:45.866)
It was really difficult to work on these particular problems in a, in an academic setting. These are things that kind of really requires scale and expertise more at the like industry level. And industry has a ton of experience engineering microbes for certain environments or for.

using certain feedstocks. And so they're like, I was just like reinventing the wheel, like doing it in academia. And so instead of staying, I spun out a startup called Pioneer Labs. And Pioneer has sort of brought together a bunch of people who are like really hardcore research science synthetic biologists from like frontier academia, and also has

hired a bunch of people who are from like Ginkgo or Zymurgen or these like big strain engineering industry players who like have really seen it done at scale and also from places like in Citro. So like industry that's using AI to help accelerate life science research. And bring like all of this sort of multidisciplinary and like

diverse experience together and we make microbes for Mars. So we engineer microbes that you could go to Mars, you could take a bucket and you could put dirt, water and just like bubble the CO2 air through it and you could grow microbes like in the bucket. And that has required just like an enormous amount of strain engineering and...

just like really good science to really define what the problem is and how to properly simulate Mars on Earth and sort of what to do with it first. It's a huge area and so part of the challenge has been trying to find the right first problem to solve when there are so many possibilities.

Polymath World (19:47.209)
Yeah, I think because people... There's a science communication problem. Generally, think the public doesn't understand where biology is compared to where it actually is in terms of the technology, the potential, what people are doing with things now and the kind of questions people are asking now. But sometimes it feels like space science gets left behind on that as well. When they're thinking about Mars, they're thinking about technological problems.

and not putting biotech into the solutions there. So, like now you've introduced Pioneer Labs, we're really going, what can you do with the kinds of work that you're doing at Pioneer Labs to change Mars in terms of its makeup and give it a biosphere, give it a potential for life that could even allow us to be there?

Erika (20:42.7)
Yeah, so it all starts with the dirt. on Mars, the dirt actually has a bunch of nutrients in it. So by Earth standards, it comes pre-fertilized. It actually has fixed nitrogen in it, which is awesome. The only difficulty is it also has toxins in it. So Mars dirt has like really high salt content. And it also has something called perchlorate, which is

It's like kind of like bleach, which famously you use in your home to kill, kill things. and, perchlorates actually, especially toxic to humans. So it'll kill your thyroid if you have prolonged exposure to it. So, you know, in the Martian famously, like you're able to grow potatoes in the dirt on Mars. And like, actually we now know that that's, that would

Polymath World (21:26.696)
you

Erika (21:34.328)
kill you because it would not work for several reasons. For starters, the salt and then the perchlorate and then even if you got the potato, it would kill you, right? So Mars, in order for us to go there, we need to remediate the dirt so that it doesn't kill us. And if we do, there's huge upside because the dirt's full of great tasty nitrogen and phosphorus that things can eat and that we could have

widespread agriculture, we could have nature, we could have ecosystems that are built up on top of pioneer species, which is this ecology term for the first organism that's able to come into some area that has very harsh conditions, maybe after a forest fire or a volcano or something, and able to create fertile soil that many more complex organisms can build upon.

So when we go to Mars, I like to imagine it as a garden. I think many visions of what space science would look like were sort of formed in the like 70s with sort of like big chrome like tanks or whatever. And I'm like, don't really want to go to Mars if we're going to live in like a sterile like metal box.

but I'd be really interested to go to Mars if we got to live in a garden and we got to actually interact with the nature around us and like, have it be mutually beneficial for everyone. as you said, Mars is a place that probably used to have, or certainly used to have liquid water and maybe used to be a place that was very hospitable to life. and it's

It's really intriguing to imagine trying to get it back to a setting like that and get to enjoy it as a human as well.

Polymath World (23:38.985)
So that's the dream. I would like to paint it in practical terms, in terms of connecting your research to making that dream a reality. Generally, most people sit in two camps. There's the people who really excited, like, yeah, let's go to Miles Tomorrow. And then those who are, it's completely impossible. You're wasting our time, like, never, never, never. I don't meet all that many people who are nuanced in between. Maybe that's just me.

Erika (24:04.654)
in the middle.

Polymath World (24:07.59)
But let's talk terraforming and using microbes to change the planet, much like microbes changed our planet to get it to a place where we could be here today. people will immediately have issues with temperature, radiation. We've already mentioned the toxicity. So and then the gravity and atmosphere differences.

How can we engineer microbes to change the planet to be Earth-like?

Erika (24:41.996)
Yeah, so let me take you back some billions of years. So early Earth was not a place that we as humans could have lived actually because the percent oxygen in the atmosphere was really low. It was like 5%.

And it wasn't until photosynthetic organisms were introduced to the planet, in that case because they evolved here, we think, that the oxygen percentage jumped to 20%, which is what we have now, which is why we can walk around. And it did that because photosynthesis, fundamentally what it's doing is it takes water and it rips the water apart with the energy in light, and it stores the hydrogens as sugars.

And then it releases the oxygen as a waste product. so fundamentally, you have a gigantic planet, when you have a green planet, it's a photosynthetic bioreactor and what it is making is oxygen, right? And so that is our touch point for a process that can change a planet's chemistry at

planet scale, which is like what needs to happen for Mars. And so in general, the approach is sort of the same. So we can use biology on Mars to do things like remediate the toxins in the soil, make it a friendlier place to build complex ecosystems. And if those ecosystems are photosynthetic, they can break the water down into oxygen and make a nice oxygen atmosphere for the humans.

Now, I think contrary to kind of how people think about like people and sort of like the general person off the street thinks of Mars as like a desert and thinks of it as like really dry, which is kind of true, but kind of not true. Mars is kind of like Alaska. So it has like permafrost under a thin layer of dirt. And so it's more like being

Erika (26:51.264)
in Antarctica, like on a glacier, like it's really cold and that's why there's not liquid water, but there's actually ice so close to the surface and a lot of it. So Mars has a ton of water, just the water we're sure is there. If you evenly distributed it across the surface and melted it, Mars would have an ocean a hundred feet deep, the over the whole planet. So there's a lot of water. And if we convert

a fraction of that into oxygen atmosphere, we would have enough oxygen atmosphere that you could walk around outside and breathe. And so that's the sort of long-term idea of how you might terraform Mars. You actually don't need to like crash asteroids into it or whatever. You probably don't need a sort of like inert filler gas like nitrogen. All you need is a

thin but sizable oxygen atmosphere and you could you could make it just using the water on Mars already with photosynthesis.

Polymath World (27:52.073)
It's a perfectly reasonable rationale. It's what happened on Earth and so it could happen on Mars, given that Mars and the Earth had a very similar history. They just happened to go in different directions. You mentioned the atmosphere. People will worry about the atmosphere in terms of it being so thin and Mars not having an active hot core producing a magnetic field like the Earth does.

Erika (27:55.246)
Yeah.

Erika (28:02.541)
Mm-hmm.

Polymath World (28:18.728)
Is there the danger of things just venting off into space? Is that a reasonable concern?

Erika (28:26.04)
things do vent off into space. So because Mars doesn't have a magnetic field, every time solar wind passes past it, it can knock low mass atoms out of Mars's gravity well, and thus Mars leaks atmosphere very, very, very, very slowly.

And I think the very, the veryness of the very slowly is like the part is like the reason we don't have to worry about this. So Mars would take Mars leaks atmosphere on like truly geologic time scales. takes like hundreds of millions of years for it to lose very much atmosphere.

And so the leak rate is so slow that we could solve it with basically today's technology. So if you flew 10 starships to Mars every year, you could fully compensate for how much atmosphere is being lost. And you wouldn't notice for like...

Polymath World (29:25.411)
Right.

Erika (29:29.012)
again, millions of years, you would just like not notice that your atmosphere is going away. So like it like is a problem if we're talking like living on Mars for geologic time scales, but civilization, civilization has only been around for like a couple thousand years. So by the time this is something to worry about, like humanities technology will have moved on, right?

I think the sort of more immediate, the more immediate questions is like, how do you get started? Right? So like changing a whole planet is quite the proposition. You know, on earth, we have plenty of climate engineering technologies and we don't even use them here. Right? So there's a decision-making, a decision-making issue. And, you know, we still have never actually put boots on the ground on Mars. And so

I think the biggest question is not sort of like what happens in the thousands of years in the future. It's more like literally what is the first step and can we get our act together to do it? Which people are really excited about, but Mars is very far away and it's very hard. And this is why we still are trying to go back to the moon because it's just closer and easier.

Polymath World (30:42.44)
Thinking about the microbes for a moment, and I both know microbes are very fragile in many respects. They're also very durable in many respects. These microbes would have to be, these engineered cyanobacteria, they need to be able to withstand the toxicity, massive temperature range on Mars, including very, very cold temperatures like...

as harsh as an Antarctic winter and worse. And also just a very, very foreign environment. talk about the gene editing aspect and what that would look like in terms of giving cyanobacteria a helping hand for Mars.

Erika (31:28.556)
Yeah, totally. we spent quite a while trying to figure out how to correctly simulate Mars on Earth. One of the big problems is we've never done sample return, so we don't actually have any Mars dirt on hand to use directly. But we do have a lot of... There have been many rovers that have gone to Mars and taken measurements on Mars. And so we...

think we have like as good a handle as it is possible to have on how to simulate Mars on Earth, both the what is it really like chemically to be a microbe in Mars mud, as well as we did a bunch of simulations about what is the day night temperature profile and the seasonal temperature profile. If you were to try to grow a microbe and say like a really, really minimal greenhouse, that could be as simple as like a plastic bag, basically.

And so we can then go into the lab and we can find organisms in the dirt on earth or in ponds, or we can order organisms from the internet that like people have already worked with. And we can benchmark them in terms of how well they would grow in simulated Mars with like a whole bunch of assays. We can, we can grow them at different temperatures to quantify, like how would they fare under that temperature profile?

We can grow them in different concentrations of Mars dirt to see like, can they only grow in a pond or can they actually grow in mud? Cause there's way more toxins in the mud, stuff like that. So we can get a good handle on what organisms are worth starting with. and from there you're then like, okay, well it needs to be a lot better. Like they need to grow. they need to tolerate way higher concentrations of the toxins in Mars dirt.

and they need to grow way faster in order to outrun the radiation damage and to actually generate enough biomass to be useful and to do photosynthesis to make the oxygen. And so we have done a bunch of work trying to quantify how should we engineer microbes for Mars. So what we did was we took three different engineering techniques.

Erika (33:52.69)
and we, we like did a race. We were like head to head. If we start with a microbe and we apply these three totally different techniques, what does the data tell us we should do? Like, what does the data say is the best way to take an earth microbe and make it better on Mars? And, the three techniques ranged from really like as simple as possible. So we just evolved it. So we just serially passage the microbe for months.

And then the other two techniques were way more synthetic. So we, we took genes out of extremophiles and transferred them into the organism. So you could kind of mix and match all the genes for many different extremophiles. and we also did something, we did retron based gene editing, which is kind of like CRISPR. It's just a different protein under the hood. we, we took an organism and we made every single base pair edit to the organism and then, and then did that repeatedly to see,

to see what would emerge victorious and be helpful. And interestingly, this did not work out the way we thought it would the first time we tried it. So we did this head-to-head competition between different methods. And the first time we tried it, we were just looking at just some of the chemical stressors in the dirt. So we were not doing the full panel and we were not doing the temperature.

And in that setting, actually the best thing to do is the stupidest thing, which is just directed evolution. So like all of the fancy synthetic biology was less good and more work. But I think that will probably not be true as we embark upon trying to make these like really polyextremophile organisms. So we're now, we're now sort of basically redoing this with like the full panel of like the salt and the perchlorate and the like

Polymath World (35:35.208)
I'm sorry.

Erika (35:50.574)
and the temperature profile of the only moderate temperature during the day and the cold temperature at night and then occasional like really deep freeze thaw. And so we'll see, we'll see. But we're gonna let the data tell us whether we should be doing synthetic biology or whether we should be just doing sort of more normal, just like cultivate the organism over and over and let it evolve. And the answer may not be what we want because we're synthetic biologists, of course it would be cool. But we'll see, we'll see what it says.

Polymath World (36:19.78)
Yeah, I'm not a bit surprised that nature and evolution found a quicker, better answer than we could straight off the bat, but that is very interesting.

Erika (36:29.774)
I think it goes both ways, Like nature is super powerful and obviously like everything we see on this planet is evidence of the power of just like normal evolution. But like that did also take literally billions of years, right? So like, and it is true that there are some scenarios where you can with human engineering do better.

than normal evolution. This is actually what I did my PhD on. So it's definitely possible. It's just like, it's not always so, and this is why it's important to do the experiment and let it tell you whether or not you should try to be a smart human or if you should just help nature do its own thing. So we'll see.

Polymath World (36:54.374)
Well...

Polymath World (37:08.602)
Yeah, people might be familiar with CRISPR. CRISPR seems to be working its way into pop culture bit by bit. More and more people seem to be familiar with it. They'll be less familiar with base editing and prime editing, new techniques that have come along recently. I am curious, just while you were talking, people can get quite emotional even about humans going to the moon in terms of like polluting it, or for lack of a better word.

Erika (37:14.86)
Mm-hmm.

Polymath World (37:36.41)
I can imagine bioethicists being bothered by us putting microbes on Mars. Have you had any pushback about your...

Erika (37:46.865)
absolutely. I mean, I think this is a huge discussion.

There's a whole field called planetary protection, which was invented before the moon landings. And basically the observation was that invasive species can be very harmful. And so people wanted to make sure we didn't bring invasive species back from the moon or bring invasive species to the moon. And so basically the rule was thou shall not move organisms around the solar system is sort of basically the logic that was

arrived at that point and we now know that there's nothing on the moon that's alive and we have a large body of evidence to suggest that there's nothing currently alive on Mars and yet

We still like kind of have a few more places we really, really, really want to look like subsurface water that we haven't looked yet. And on top of that, like Mars is such a like tasty candidate for like maybe it used to have life. I mean, it really did used to have liquid water. It really seems like the sort of place that would have life on it. And so, you know, there's always the possibility that maybe there's something like dormant in the soil or frozen in a glacier or something that like could be revived maybe.

And of course it's impossible to prove something doesn't exist. So that possibility will always be there. And it's a lot easier to look when we have good assurance that there's not life from Earth that's been brought to Mars. And so this is like a big part of the challenge. It's like we're moving into this new era of exploration where we're probably going to send humans to Mars and humans are covered in microbes. So it's like the place is no longer sterile as soon as you send

Erika (39:39.452)
human and yet the search for life continues, right? Because with humans there this is actually the best way to

forward the search for life, because we'll suddenly have an enormous amount of additional flexibility, because we have human scientists there and can just try a lot more stuff. And so mean, it's a huge discussion. As we move into the solar system, we want to conduct ourselves well. It reflects on us and our ethics how we conduct ourselves.

I guess in my view and in the view of many people, like going somewhere and having a net positive externality on the climate, like the presence of humans making Mars a nicer, more habitable place, I see that as positive. Some people would prefer to leave it.

sterile and like leave the rocks alone sort of attitude and it's like not obvious like what the right solution is. This is philosophy. I think for now like in the immediate future what we're suggesting is to send a mission to Mars that does the following. Okay it takes a little scoop of dirt it adds water

and then we incubate it and we see what happens. Right? So let's just check if there is something like dormant in the soil that could be revived by, by rehydrating it, which is possible. Like Mars used to be really nice. Like it's possible that there's stuff there leftover that's just dehydrated and then try that again after adding some fertilizers to see if it's nutrient limited. And then if none of that works, try it again. I'm adding.

Erika (41:29.53)
a microbe you brought from Earth, but that requires food. So we have a microbe we've made that can be used to make bio plastic, which is like,

can use it to make like 3D printing filament. So it'd be super useful to use on Mars, but you have to feed it acetate, which is like vinegar. You can make it really easily from the carbon dioxide atmosphere on Mars, but it's not like around. So if this microbe gets out, it will be dead five different ways. It only grows inside a nice container and you have to feed it. So it's not like, it's not going to terraform the planet on its own, but it would be a really useful proof of concept that we could use biotextile

on Mars and it would open the door for going to Mars and making just like infinite amounts of 3D printing building material from from raw materials. And so that that's like the sort of path I think we can navigate. It's like we're going to send microbes to Mars, whether they're on humans or otherwise. There's a lot of value that's unlocked with biotech and we have to proceed with caution and and like continue to do search for life experiments.

right? As you go along. The search for life doesn't end just because you have humans there or just because you have agriculture there. It just like begins anew with new methods and new capabilities to search for it.

Polymath World (42:51.812)
I love that. I love that so much. I have a million questions, but I know we don't have time to ask them all. Part of the concern I've heard from bioethicists is that if we did try and terraform Mars through biological processes, like with cyanobacteria that were edited to thrive on Mars to oxygenate the planet and give it the beautiful atmosphere that we enjoy here.

those microbes could kill any life that's already on Mars. There's this wonderful poem by the astrophysicist Arthur Eddington that says, we found a strange footprint on the shores of the unknown. We looked a little deeper and lo, it is our own. Sort of discovering life on Mars than discovering it was actually our life that we'd brought along in the first place. But pushing it to the extreme, what if evolution took it in a place that we didn't want it to go?

and we engineered microbes that would be harmful to us on Mars that could prevent us from thriving there.

Erika (43:57.486)
Totally. I think this is sort of gets at the heart of like, humanity's having a little bit of our struggle with like our relationship with nature period, like at the moment. So, I mean, humanity has great capabilities to alter landscapes and has sometimes used that for what people usually would call good. So like making fertile agricultural

you know, fields. humanity has greened many places and like made them more habitable and worked together with nature to do so. However, like we have also many times, like done things with biology that had unexpected negative consequences, not necessarily because we were malicious, or even because we could have known better.

but just because biology is complicated, right? And like things do evolve and you don't always know how they will evolve. And I guess to me as someone who has spent like...

a lot of my career like studying how to use evolution as like an engineering tool. Like that is the power of it, right? Is that evolving systems are a constant source of novelty and surprise. And that is something that like is why I think they are.

like philosophically net positive. Like I think nature good, more nature better kind of on a very simple level. And part of that is because they are full of surprises. Some of them may be bad, right?

Erika (45:41.406)
And I think that like sort of comes with the territory and as humanity we sort of have to grapple with that. It's like, do we want when we go to Mars, do we want to deprive ourselves of nature because a sterile, all chemical, mechanical, like punk, like future is somehow more predictable?

Or when we go to Mars, do we want to bring nature and its complexity with us and the good and bad that like come with that? And like, I know the answer for me, which is that I like flowers and like, I don't want to go to Mars if there's no flowers, but, others disagree. Right. And I think that this is part of what's fun about space science and part of how it relates to life on earth. Right. Which is that as we

As we move out into the solar system, the choices we make and what we choose to bring with us reflect a lot about who we are and what we care about. And that has impact at home too. So anyway, this is all just to say, know, yes, evolving systems will surprise you and that is the fun. That's like why they're beautiful. Because they're like a little dangerous and they can have teeth.

Polymath World (46:53.032)
Yeah, generally I'm with you. I prefer life to non-life. And I think part of the attraction of Mars, and the moon as well, is that they're something of a blank slate. Not a complete blank slate, but they're a new frontier for potential civilization that seems like, well, we can be creative here, which is wonderful.

I talk to students about Mars and terraforming comes up. Students are always interested in the time scale. obviously biologically it took millions and millions and millions of years on Earth from the great oxygenation event through to us flourishing. So, but being some sort of planetary engineering on our behalf and maybe combining different terraforming processes, what I...

do you think of the two extremes of the time scale?

Erika (47:52.032)
So this is actually part of the cool, this is part of what's really cool. terraforming might take way less time than you think. if terraforming were not financially constrained, it's possible you could make Mars green. And what I mean by that is like a global thriving biosphere, but you as a human would still need a mask. So you would not have accumulated the full atmosphere yet, but you would have a thriving planet.

You could probably get to that in like 30 years for the cost of the interstate highway system. like, not that long and like the interstate highway system was very expensive, but also like not that expensive for like a planet, right?

Going from that, that's your bioreactor, right? Like once you have a green planet, that's a bioreactor that's making atmosphere for you. And the accumulation of oxygen would still take some time. So it would still take like a thousand years roughly or something like that. So we humans, unless the longevity people really step on it, like we won't get to walk around outside on Mars without a mask.

but we would be able to create a planet that is alive again. And there's an enormous amount of benefit that comes from even para terraforming, so green housing.

like a section of Mars, which is that when you go there as a human, suddenly there's stuff waiting for you, right? You have supplies, you have food, you have like the ability to do all sorts of remediation of your waste, right? Like you have a place to reload.

Erika (49:42.336)
supplies when you get there so that you can you can come back or stay and so there's there's enormous benefit even before you talk about doing something to a whole planet to just doing Making a thriving area of mars in an enclosed setting which I think is also like much more palatable obviously from an ethical standpoint So I think that's something that's in the near future. I would actually be shocked if like I don't see you know humans on mars

in a place that has beautiful gardens and agriculture in an enclosed area in the next few decades. I think that's certainly in our future.

Polymath World (50:22.566)
Yeah, it's again, it goes back to the science communication problem. think really people really don't realize what's possible because they don't realize the tools and the technologies and the research that's happening and is present right now in the life sciences. I have so many more questions I'd like to ask you, but I know we're kind of coming out of time. We'll have to find a way of talking to you again. But we always ask, you know, what advice would you give to students or young people or people looking to retrain who

Erika (50:41.752)
It's

Polymath World (50:50.598)
are excited by your field and would want to get into it, what would you recommend they do?

Erika (50:59.278)
I I often, I have made most decisions in my career being

purely driven by curiosity and really trying to pay attention to what actually inspires me or what makes me feel that I have the thrill of the chase feeling of doing science. And I just in general recommend doing that. There's all sorts of terribly prestigious careers one could have, but if you're not into it or you don't enjoy it, I think it's...

not really possible to do really good science. think really good science comes from building really deep intuition about an area. And that's only possible when that's the thing you think about in the shower. Like you have to find that thing that just transfixes you. As one thing I often do when I feel like I might be intrigued by a new area, I will write down the 10 first really genuine questions I have.

about it and it always gets hard around number seven. Like it's actually really hard to come up with 10 questions. Write down 10 questions and then like go through and answer them one by one and by the end of that you will have like gotten under the surface of like whatever new thing and sort of cultivated your own curiosity in it and allowed yourself to sort of guide you toward problems you care about. So that's something I, it's a, that can be a lot of fun.

Polymath World (52:22.12)
That's terrific advice. Thank you so much. If people want to know more about you or about Pioneer Labs, where should they go?

Erika (52:30.998)
Yeah, you can go to pioneer-labs.org. We also have a sub stack, so we write, you know, all the time about the science we're doing. So you can, you can sign up to follow along with that. And you can find me on Twitter, erica underscore alden underscore D on Twitter.

Polymath World (52:51.378)
Thank you so much. recommend the Stubzack. It's really, really interesting. Thank you so much. It's been such a pleasure talking to you today and all the best. Look forward to catching you again sometime.

Erika (53:01.132)
Thanks, you too.