How do you introduce yourself, scientifically?

My name is Mia Miyagi, and I’m an evolutionary biologist, which means that I study how the process of evolution works and how that process has generated the incredible biodiversity that we have today. More specifically, I’m a theoretical population geneticist. Population genetics is how we think about evolution and variation across entire populations. In other words, how individuals are related to each other, and how turnover in these individuals over time changes the population they make up. I say I’m a theoretical population geneticist because rather than collecting data directly, which for some people means going out into the world and collecting insects, getting data from hospitals, etc., I spend my time thinking about and simulating evolutionary processes. 

What are the implications or broader impacts of your work?

In the context of evolutionary biology, population genetics provides us with quantitative tools to understand the past; it lets us think about how the fabulous biodiversity that we see today came to be. 

More personally, this work helps us think about the history of humans on earth. Much of what we know about human history is informed not only by archaeology and anthropology, but also by genetics. Population genetics helps us have a more comprehensive view of the past by helping us understand the interactions between us and other hominid species like Neanderthals.

What do your data look like? 

I work with genomes from individuals within a population (genomes are the full set of DNA from a given organism). I recently worked with some butterfly genomes that had been collected and constructed by another student. Of course, this is a huge amount of work, and my own research wouldn’t be possible without data like this from other scientists!

These genomes ultimately help us test models explaining how different evolutionary processes work. For instance, if we are interested in seeing if two species are hybridizing (crossbreeding), we can use theory to create a model of what the genomes of these two species should look like if there really is gene flow between them. We can then use these models to generate simulated data sets that we can compare to the real genome data to see whether our model matches what is happening in the world. This can help us understand whether our ideas about what’s happening in the real world are correct. 

What do you hope this reveals? 

We all have this idea of a tree of life where organisms are related to each other through splitting branches. But it turns out it’s really not so simple. This is even evident in our own evolutionary history. When our ancestors started to diverge from other species, there was still genetic information being exchanged between these different species through mating. One famous example is that some Tibetans have a gene that makes it easier for them to breathe at high altitudes. This gene actually came from a hominid species called the Denisovans. What we’re learning through this work is that so much of life’s history is not just this nice branching tree, but rather a more tangled web of genetic exchange. 

What makes an evolutionary biologist, or theoretical population geneticist, unique? 

What makes theoretical population geneticists different from other evolutionary biologists is that we often study the quantitative aspects of the evolutionary process rather than studying a specific organism or system. More broadly, I think many branches of science are about prediction or experimentation. For example, making predictions about climate change, or trying to make planes fly more efficiently. But evolutionary biology is somewhat unique because you get to do something retrospective; you’re trying to reconstruct the past. It is a fun way of thinking about the world, and it lets you interact with nature in a fundamentally different way.

Is there a common misconception about your field? 

People have a lot of misconceptions about evolution! People think that evolution is about the origin of life, but it is more about how life changes through time rather than how life came to be. Another common example is that some people  think that humans “evolved from monkeys.” At some level that’s not totally wrong. But, a better way to think about evolution is to understand that all the living organisms we see today are related if we go backwards in time. It’s not that the monkeys alive today are your great-great-great-grandmother, but that we and all the primates alive today have a common ancestor, and that common ancestor is closer to the present than the common ancestor between us and, say, fish. 

Is there anything you would tell people interested in becoming a theoretical population geneticist or evolutionary biologist?

Being able to study the process of evolution helps you gain an appreciation for the diversity of life. It gives you a view into the natural world that is otherwise hard to see, and it does so in a way that is much more present in our day to day lives than what you might have in other theoretical fields, such as theoretical physics. 

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To learn more about Mia’s work: 

• Follow them on Twitter: @MiriamMiyagi
• Check out this article about their recent work with butterflies

This interview with Mia Miyagi, Graduate Student in the Department of Organismic and Evolutionary Biology at Harvard University, was conducted and edited for space and clarity by Malinda J. McPherson in September 2020.

Malinda J. McPherson is a PhD candidate in the Harvard University/MIT Program in Speech and Hearing Bioscience and Technology.

This piece is part of our special edition on the day-to-day lives of researchers working in many different fields of science. Are you interested in learning about a different type of scientist? Check out the rest of the special edition!