Jake Drewes had a pretty normal childhood, going to school, doing his homework, and hanging out with friends. But once a year, a research team would visit Drewes and his brother to put them through a series of tests.

“When I was younger, it was mainly cognition, like testing our reading skills or memorization. And then when we got older, there was one where they had an electrode cap on me,” he recalls.

In his teenage years, the research team also tracked his and his brother’s social media usage for six months with each brother’s consent, and even had them do cognition tests while in an MRI machine.

“They had us laying there, and had this cage over our head with a mirror so we could see a monitor in the back of the tube so we could do some kind of memory test while they were scanning our brain,” he laughs.

While all those tests might sound like something out of a Hollywood movie, they are actually quite common; Drewes and his brother are twins, and the kinds of studies they participated in investigate whether individual differences are more explained by a person’s genetics or social environment––a question of the importance of nature versus nurture. 

“I always enjoyed it,” Drewes recalls, “And when it came time to thinking about what I wanted to do with my life, my first choice was wanting to do twin study kind of stuff.” 

While his own experience as a research subject got him interested in science, his interest in what kind of science he wanted to morphed as he moved through high school and college, becoming interested in neuroscience next, and then biology. By the time he was finishing his bachelor’s degree at University of Colorado, Boulder, he was doing research on viruses.

“I’ve been pulled in every direction,” he smiles.

As he began searching for graduate programs, Drewes connected with Heather Bean, whose lab researches microbial interactions and diagnostic tools for diseases like cystic fibrosis and valley fever. Drewes thought he’d swtich from viral diseases to bacterial ones when he started his microbiology PhD. But soon after, Bean invited him to switch his research focus yet again, and join a collaboration her lab had with Ferran Garcia-Pichel, whose lab researches soil microbes. 

Now, Drewes researches the interactions between bacteria in biocrust, or bacterial communities that live on top of dryland soils. Specifically, he looks at what chemicals certain bacteria send out to signal that they want something from other bacteria in their biocrust community, almost like asking a friend for food. Beyond just studying what signals they’re sending each other, he also investigates how those signals change depending on the environment the bacteria are in and different bacteria’s ability to turn food into energy. 

In working to better understand how all those bacteria work together to form biocrust, he hopes his research can help replace the biocrust that is rapidly being lost across the world’s drylands due to habitat degradation.  

“The eventual goal is biocrust restoration,” Drewes explains, “It can take a really long time for biocrust to develop––sometimes decades. And in the meantime, all that dust is being blown around in dust storms and haboobs, making those storms more severe.” 

And while Drewes’s curiosity took him far beyond his original interest in twin studies, he feels that the interdisciplinary nature of his work suits him. 

“I really like that my research is microbial science, but also ecology. I have like hands in all these different fields,” he says. “When ASU accepted me, I’ve really gotten to see how collaborative and innovative this kind of research is. I’ve been very happy working and staying here.”  

Note: This story is part of an ongoing series profiling graduate students in the School of Life Sciences. See March’s featured students here.  

The research that goes on in the School of Life Sciences spans a huge and fascinating variety of subjects. The graduate students who make up SOLS are no less diverse or interesting, arriving at their respective research from different places and with different passions. Here, we recognize a handful of these graduate students, their work and what motivates them to pursue it. 

Allison Hays – Neuroscience 

Our childhood experiences have a huge impact on the rest of our lives; they shape our beliefs about the world, the relationships we form, and our physical and mental health well into adulthood. Allison Hays, a second-year neuroscience PhD student in the BEAR Lab, is diving deeper into understanding how our experiences are so impactful by exploring their interaction with genetics. 

Hays specifically thinks about how childhood experiences affect certain cognitive functions, like the ability to remember things, pay attention, and switch easily from one task to another. But rather than looking at the brain to figure this out, she looks at our spit––the easiest way for her to get samples of DNA. When she looks at spit samples, she doesn’t just try to read the DNA they contain; she’s more interested in seeing how the DNA within them is being regulated. Specifically, she looks for occurrences of DNA methylation, which is a modification that prevents gene expression.  

“We don't have all of our DNA being expressed at one time. There are things that turn gene expression on and off, or up and down.. So, what we look at is not necessarily what genes you are given, but what genes are on, off, up, down, etcetera. So that's then going to affect... your biology, your health, and cognition. I specifically think about how stressful experiences can be associated with poorer health and different rates of development and aging- which may ultimately go on to impact a variety of things.” 

So, Hays measures the cognitive performance of her research subjects, assesses how stressful their early childhood experiences were and looks at what genes are turned on or off in the DNA in their spit samples. With all that information together, Hays can start to understand how early childhood stress can change gene expression and affect cognitive performance. 

This holistic look at stress, genetics and brain function altogether excited Hays, who conducted related research with the Arizona Twin Project and the Memory Attention Control lab at ASU as an undergraduate. Now, she’s conducting novel work that she hopes will one day improve how scientists assess and improve humans’ health and wellbeing.  

“I think it will be extremely important for assessing people's level of health risks depending on their childhood stress levels, and monitoring whether any types of treatments or interventions are working... By looking at the gene expression, we’ll finally be able to see on a genetic level which treatments are working and which are not.” 

Isabel Torres – Environmental Life Sciences 

Arizonans might think they’re well-acquainted with the desert, having lived among its summer monsoons, soaring temperatures, and temperamental dust storms. But most Arizonans have no idea why the desert is important. 

Not Isabel Torres. The second year PhD student in the Throop lab is dedicating her research to better understanding deserts and other dryland ecosystems, which most people have overlooked.  

“Deserts are amazing. People think that there's nothing living or going on there. But there's so much activity.” 

A third of the world’s human population already lives on drylands, or ecosystems like deserts defined by water scarcity, and that number will only increase: by the end of the century, drylands will likely make up 56% of Earth’s land cover, Torres explains. To protect the people who depend on drylands, scientists must understand how to best manage and care for that land. But that’s not something they currently understand. 

Torres plans to help correct that. She’s spending her PhD doing field work to study how carbon cycles through dryland ecosystems, which is important for scientists who make models that predict what the climate will look like in the future. Current climate models for dryland ecosystems rely on data collected from other ecosystem types, which is troubling –– it means that those models are inaccurate. Torres aims to generate data that can be used to make accurate climate models, which will help land managers take care of the land. 

That goal, Torres shares, is inspired by her hometown: “I grew up in El Paso, Texas. It’s a desert. But it wasn’t always a desert. Back in the 1800s, it was a grassland. It was pretty and beautiful. But then they overgrazed the landscape, leading to desertification... So, I’m really interested in land management practices and how we can take care of the land.” 

Torres recognizes that living on drylands is tough: water and other resources are scarce, so people must work to prevent desertification where they can. At the same time, she loves the desert, and though she knows life there is tough, she doesn’t want that to stop people from seeing how much the land still gives us. She hopes her work can help people protect the land in return.