ARTICLE № 006  JUNE 2018


Geologist | Educator

Callan greets with a cheerful hello in front of the Northern Arizona University Geology Building, shortly after co-leading a short course for the GSA Joint Session Meeting in Flagstaff, Arizona. We walk to a nearby sunlit courtyard surrounded by cottonwoods and pines, and sit against a concrete bench. We are surrounded by wildflowers and bees, the snow of cottonwood seeds, the chatter of birds, and the gentle breeze. Callan is relaxed in posture, but quick with memory and response as we delve into childhood experiences with nature and science. From insects in the woods and science fair projects, to multidisciplinary interests and fatherhood, Callan shares his path and perspective with unwavering energy and jaunty demeanor.

So, what I think drove me into geology is a little bit inelegant, but...

...Inelegant? When did you find geology?

In college. So yeah, when I went through high school I was pretty sure I was pretty into biology. And I still am. I mean biology is awesome. You know, I care less about the boundaries now than before. Chemistry, physics, geology, biology, astronomy… it's all one big thing.

Let’s take it back to your formative years first, then.

You got it.

Where did that love for biology blossom? Were you provided access to nature? Did you engage with nature? 

Sure. So, you know, my dad would take me for hikes, my mom would take me to the museum. I did a lot of drawing and I drew a lot of natural stuff. The house where I grew up in was right across the street from a big tract of woods. I spent a lot of time kind of roaming around in there as a kid. And I have very fond memories of finding hognose snakes, and catching frogs, and a strong focus on insects, bugs, and things like that. I wasn't very into rocks at that point. It was more about creepy crawlies at that point.

Other than a focus on insects and bugs, was science a part of your life?

I mean, the memories that I have of science in elementary school were specific projects that certain motivated teachers had us work on: bug collections, and rock collections, and things like that. It sort of hit home as something that I was good at in middle school. In seventh grade, we had to do science projects, and I did one on whether or not music helps plants grow. I did a controlled experiment with garlic plants where I had a control group, a group that listened to “Weird Al” Yankovic, and a group that listened to Pachelbel's Canon. And, I grew these garlic plants up for three or four weeks, and just measured their height. Pretty simple little thing; but, I ended up getting first place in the Botany category at the state science fair, and I was like, “Wow!” You know, that's some serious validation for a little seventh grader. And then I came up with similar projects in subsequent years and didn't end up doing as well, but I had a lot of fun. It allowed me to be like, “Ah! Well, this year I'm not going to work with garlic plants. This year I want it to be leeches. And so, I'm gonna test something about leeches.” I forgot what it was… temperature? I don't know. And then another year I used the science fair as an excuse to get my parents to buy me tarantulas. We went through a suite of sort of pets in the household. We had a lot of critters: hamsters, and rabbits, and snakes, and fish.

Are your parents educated?

Yeah, they're both college educated. In my Mom's case, she's a first generation college graduate. My Dad: second generation. But yep. So, they had professional jobs. My mom was a teacher, my dad was an engineer. My dad still is an engineer—the guy's about to retire.

Other than your father being an engineer, was there any interest in science or nature among your family?

You know, my mom I think appreciated nature but more from an inspiration perspective—literature. She was an English teacher so she was teaching Shakespeare and you know, other sort of classics that are part of the standard curriculum. She also appreciated poetry, and never really succeeded in getting my brother and I to appreciate poetry as much as she did, but definitely made pretty voracious readers out of us. So you know, different ways of getting there.

Would you say that your parents were hands-on or hands-off with your upbringing? Were they like, “This is the world, go explore,” or was there more direction?

A bit of both, I reckon. You know, my father saw that I liked drawing, so he got me a cartooning class at the Smithsonian as a gift for my birthday one year. He really liked stamps and he wanted me to be into stamps, so he got me a stamp collecting kit, and I didn't do anything with it. So, there were some of those efforts that were appreciated, and some that I kind of rebuffed just because I didn't really care. But, he didn't take it personally and he never tried to push those stamps on me again. [Everyone laughs] It's funny though, now he edits this newsletter of people who are interested in the stamps of Colonial French Indochina.

That's very specific.

It is very specific. And one of the ways that we sort of bond now as adults is that when he has a new issue ready, he has me do the copy editing. So I look through it for mistakes and punctuation. I mean, I don't know anything about French Indochina or anything about stamps, but I can spot when things are formatted incorrectly. [Everyone laughs]

So, parallel to your father, you’re also interested in history, right? Your website specifically lists the “History of Science,” and “Intersections of Geology and Human History” as interests.

Sure. More so as I get older, I think. I get more into the human angle. I mean, it is really quite superficial in the grandest scheme of things. But then again, you know, I am a human. And the fact that I'm here is a consequence of my mom and dad being humans and getting together in the past. And they of course have a similar ancestry, where all these sort of meetings between people in the past have manifested in the fact that I'm alive. And so yeah, it's interesting to me from that perspective. If there had been some different outcome, or some different war in the past, or some politician made some different decision, then history would have turned out differently—I might not well exist. So yeah, it's all interesting to me from that angle.

So I just finished a book by Walter Alvarez, the guy who discovered the iridium anomaly at the end of the Cretaceous—he came up with the impact hypothesis for the extinction of the dinosaurs. And this book is about what he calls “Big History.” And so, it was about the cosmos... the evolution of the universe over time, the Earth, life, and then humanity. And, you know, I'm interested in all those things and see them not as separate but as part of one continuous pageant.

... there's gonna be some angle... where the efforts that I put into giving people a better sense of their geo-heritage, or alerting people to atmospheric changes and the consequences for climate, can manifest in some way that ends up impacting [my son's] life.

So, to me, one of the things that I love about geology is sort of how essential it is. It is, you know, the study of the Earth... this planet that we live on that does all this cool stuff and has been doing it for a long time—making stuff like rocks and air and water that we depend on. And so, that viscerally ties me to geoscience. And in the same way, I'm a living organism. And so, knowing why nerves regenerate or don't, or my evolutionary heritage... like, that's fascinating to me. Because again, it's about that essential stuff that's at the core of who we are.

So, you don’t see it as having multiple interests.—you have a single interest.

Yeah. Yeah. “Why things are the way they are.”

That's interesting. It could easily be seen by anyone looking over your CV, or going to your website, that you're pointed in multiple directions, but I'm following you.

Yeah. It doesn't feel hypocritical or disjointed to me to be interested in all that stuff. I am pointed in a lot of different directions, but it's more because I'm doing this thing for this organization, and that thing for that organization. And I've got this freelance project. And I write this blog. And you know, there's all these different directions I’m pulled in, and that's just completely in this sort of self-initiated professional realm, completely separate from family and responsibilities.

Speaking of family and responsibilities… you’re also a father.

Yup. I've got a five year old boy—Baxter. Five and a half now, I guess.

Are you instilling your all-encompassing interests in him?

Well, to some extent. I mean it's kind of hard because he's five and a half, so you can’t talk about things on too deep of a level; but, we do talk about a lot of stuff. Like, we took a hike the other day and he was asking me about nuclear weapons. And so I was like, “Okay. Well, you know, there's this binding energy that's in the nucleus, and if you release that, there's a whole lot of energy that gets released and it's really…”

... is he asking that because of the current climate?

I don't know what the deal is. I forgot the exact pathway that led us there. He's really into Minecraft. So, we don't play video games—we don't even watch TV—but, he's got friends at school that are into Minecraft and so they draw their Minecraft pictures together. And so then he's brought that home. And I think there's something that maybe blows up in Minecraft, and so that might've been what led us there. At any rate, there's some stuff that I don't really feel like it's appropriate to talk about with him at this point. But, you know, nuclear weaponry is far enough in the past, I hope [Laughter], that I felt like it was kind of safe to talk about it. So, there's a lot we talk about. He's a relatively curious kid. I'm grateful for that.

Do you think about legacy—all your interests and accomplishments—with respect to your son? As time moves on, and you're not here anymore, there are these special things that you've created that...

... maybe. I mean, I do a lot of my work sort of independent of thinking about him, because... I mean, some of it's really relevant to him, but a lot of it's kind of not. Unless he chooses to get into it. And he's made some comments recently that have totally lit me up in terms of like, “Oh! Whoa! Did you hear that? This kid's talking about rocks? That's really exciting!” But I don't want to be putting the stamp catalog down in front of him, you know. [Everyone laughs] If he wants to go that route, that's awesome, and he's welcome to it. I have a colleague that I teach with; his daughter just graduated with a geology degree, and he couldn't be prouder. So, it'd be cool if it worked out that way, but he's going to be his own guy. And, the majority of my influence has already been input into the system. So, yeah... I don't know. I guess when I think about legacy, I'm largely thinking about work-legacy. But, there's gonna be some angle there, where the efforts that I put into giving people a better sense of their geo-heritage, or alerting people to atmospheric changes and the consequences for climate, can manifest in some way that ends up impacting his life. But, I don't really necessarily think about it that way…

[Drifts of cottonwood seed float by. One catches on Callan’s chin stubble and he gently pulls it away.]

...a little bit of cottonwood. Populus tremuloides.

But, you do think about legacy, then?

Um, I just gave the wrong scientific name for the cottonwood. It's Populus fremontii, not tremuloides.

Is it?

It is. Yup. Fact check this.

[Populus fremontii is a native cottonwood of Flagstaff.]

So... legacy.

Legacy. Yeah, I'm actually sort of midway through my career, so maybe it's time to start thinking about that. So legacy. Yeah. I mean, I've been writing that geology blog now for more than 10 years. And you know, I'm 44, so that's approaching... well I guess... like next year it will be a quarter of my life that I've been a geology blogger.

That's pretty wild. I feel like it was just yesterday that geo-blogging was something very new.

Right? Yeah. Yeah. And something that a lot of people were doing, and now it feels like it's really sort of had its moment and there are far fewer people devoting the time to blogging now. It's much more about the short attention span, you know—quick-fix of Twitter.

So, that blog is a big piece of my legacy. And, it's sort of digital and potentially ephemeral. If somebody's server crashes somewhere, all that goes poof. But, it's really neat, because a lot of my blog traffic comes from people clicking on links from Facebook or Twitter when I announce I've made a new post; or they subscribe. But, a lot of other people get there because they're searching for something. You know, “What's the geology of Harpers Ferry? How can I use the angle between bedding and cleavage to figure out if beds are overturned?” And I've written about these things, and they can learn. So that feels great. Just to know that those 10-years worth of writing is out there, and people are accessing it right now as we're talking, and gleaning some measure of insight from it. 

I blog in the morning when I'm drinking coffee and my brain is sort of spooling up to maximum RPMs. The act of creating is sort of the way of waking myself up. You get the caffeine on the one hand, and the endorphins from creativity on the other.

This is a slightly different angle, but, it's been really good for me to figure out when I'm doing things right, and when I'm doing things wrong. Because, people give you feedback about stuff you're doing when you post it online. And that's been really useful because there are some things that I was doing... and you know... I'm trained as a structural geologist, but my job is to teach Intro Geology. And, part of that is teaching things I don't really know all that much about; like glaciology, and geomorphology, and coasts. So, as I sort of grapple with that material, I write up stuff about how I'm teaching it and people have given me feedback about, you know, “Yeah, that's a good way of doing that. Very clever.” And other times they're like, “That's outdated. You shouldn't be teaching it that way.” And that's great; because essentially, I've got all this legacy material from previous faculty at my institution, and the textbooks we use, and it's great to be able to peer review that, you know. And I wouldn't get that feedback if it weren't for me putting that stuff out there. So that's valuable, and it's something I've really gotten from the process.

And the other thing that I think the whole blogging/geoscience-outreach thing has done is it's netted me a series of opportunities. Because people are like, “Oh look. This guy is doing this thing. I wonder if he'd be interested in that?” And it's gotten me contract work on textbooks, and invitations to participate on grants, and things like that. So there's been a real benefit to the time I've invested in it. The great thing about it is, I don't really actually invest that much time in it that would be otherwise going to real work; because, I blog in the morning when I'm drinking coffee and my brain is sort of spooling up to maximum RPMs. The act of creating is sort of the way of waking myself up. You get the caffeine on the one hand, and the endorphins from creativity on the other. And by the end of that, you hit publish, and you're like, “Okay. Now I'm ready to go and check my email.”

You were trained as a structural geologist. You teach Intro Geology. You’ve been geo-blogging for 10 years… When did geology enter into your life?

In college. So yeah, the first half of my college experience was in the sort of pre-Internet, pre-email era. So, in 1992, at the College of William and Mary, incoming freshmen, to pick their classes their first semester, were dumped into this big hall. And around the fringes of the hall were tables. Sitting at those tables were faculty members with tickets. Literal rolls of tickets for our classes. If Biology 101 had 300 seats in it, they had 300 tickets to give out. And so as a student, you had to prioritize, “Well, I want this class, so I'm gonna go stand in this line and get this ticket. Then, I'm going to go over there, stand in that line, and get that ticket.” So I got the classes I wanted and I still needed something to fill out my schedule. And I saw two old guys sitting at a table and I was like, “What do you all teach?” They said, “Geology! It's really great! You should take it!”

Did they have beards?

No, they were both clean shaven. But they were both white men with gray hair—so, typical in that regard. They were very friendly and I was like, “Geology? Is that rocks?” And they said, “Well, it's more than rocks. It's the whole Earth. You should give it a shot.” So I gave it a shot and I did well at it. I found it interesting.

Was there a spark or you just found it interesting?

I found it interesting and I was competent at it. I still felt a strong affiliation for biology. I had a mentor who's a biologist—a developmental biologist—but also an artist. Also, very interested in literature. He got me into reading Ed Abbey. We would go for coffee and talk about life, the universe, and everything. So I still felt really connected to biology through that relationship. And I got into birds in college and I started paying attention to birds, which is still like a huge thing, particularly at this time of year when they're all migrating. I'm kind of a freak about them.

So what I think drove me into geology is biology required two semesters of chemistry; geology required one year of chemistry, and I wasn't all that good at chemistry. [Everyone laughs] And so I said, “You know... I can just take the biology classes I want and not take the chemistry classes I don't want, and get a degree, and all will be well in the world. So that's what I did. And that's fine, I think. I don't miss chemistry. I mean, I'm much more motivated by it now. But back then it was just like... I just did not see the point.

So then you switched from biology to geology?


Because of chemistry?

Because the chemistry. [Everyone laughs] Yup.

Did you feel like you were giving up something by leaving biology?

Sure. But you know, life is full of choices like that, so...

... did you get over that fairly quickly? Or did that carry with you the whole four years?

I made that decision my senior year. Just when I was taking that third semester of chemistry, I was like, “I don't want to be doing this.” My senior year, I was very motivated in college, doing lots of stuff. Writing for the newspaper. Sierra Club. I don't know, like a zillion things—I was involved in a lot of organizations. And my senior year I made this decision to sort of clean house and cut loose ends and you know, I sort of dropped all those affiliations, save writing for the newspaper—I wrote a natural history column. But as part of this process of sort of like, you know, “I don't want to be wasting time doing these things that I don't really actually feel passionate about,” chemistry fell into that category, biology didn't. I mean there were lots of cool classes to take. I took ornithology, and entomology, and developmental biology. I took a course in metalloproteases. You know, all kinds of evolution courses. Nerve regeneration. Yeah, I loved all that stuff. It's great.

[Chatter sound of a bird in the distant pine trees]

What's that?

That was a woodpecker of some sort. I don't know the woodpeckers here.

It reminded me of a flicker.

Yeah... well... flicker is a woodpecker... Yeah... So, that takes me back to that thing I just mentioned about in college: the newspaper column I wrote. I decided that I wanted to do sort of a David Attenborough-y kind of thing in the newspaper, where I was an editor anyways. So I created this column called Wild Williamsburg. And every week I would do a column on squirrels, or local fossils, or why leaves change color in the fall. And it was great because it was like a little prompt every week for me to go and learn a little bit more about something. You know, “What's the deal with eels in our rivers? Where do they go? How often are they here? How big are they? How many eggs do they lay?” And then sort of putting that into a concise, little form. It was kind of like writing a blog post back before blogs. So that was great because it was basically me using that platform to advance a natural-history-understanding among that population—the people who read that newspaper.

[Repeating chatter sound of a bird in the distant pine trees]

Yeah, flicker. So you guys have Red-shafted flickers here?

We do, but every now and then we get a rare Yellow-shafted. You seem to have a relentless amount of energy. What motivates you to have that kind of energy?

I don't know. Yeah... I don't know... that's a great question. I don't know that I've thought deeply enough about that. But clearly I like to do. I like making stuff. And I like sharing stuff. I like sharing my understanding of the way the world works—that's a motivation for a lot of what I do. And I like making cool stuff. I like writing a well constructed article or blog post. I like making a good drawing. I like it when one of my digital visualizations turns out really well. There's a satisfaction in the act of creation. So you put those two things together and you have sort of a record of success, and then people start asking you to do other stuff. And, you know, part of the reason I do so much is that I just have a hard time saying no.

Is there something more you want to do that you're not doing now?

Um, yeah. So, if I had more time, I'd be interested in doing a geology podcast. I think it'd be great if the people of the world could download a new episode every week of some geology podcast that talked about current events; talked about new research; had interviews with scientists; had some sort of travels-in-geology thing. So yeah, that's one thing on my list. And that's been on my list now for years, where I just thought somebody really needs to do that. I also want to do a book—write a book about the geology of the mid-Atlantic region, which is not nearly as well exposed as this stuff out here, but tells, in many ways, a better story. So, I'd love to sort of boost that. Yeah. I feel like I've got a pretty coherent vision of it at this point, and that would be something I'd like to do. Yeah. Those would be the top ones on my list.

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Current Status & Academics

Callan Bentley is currently an assistant professor of geology at Northern Virginia Community College in Annandale, Virginia, a Fellow of the Geological Society of America (GSA), President of the Geo2YC Division of the National Association of Geoscience Teachers (NAGT), a contributing editor to EARTH magazine, and author of Mountain Beltway geoblog, hosted by the American Geophysical Union (AGU). Callan holds a Master of Science degree in science education from Montana State University, Bozeman, a Master of Science degree in geology from the University of Maryland, College Park, and a Bachelor of Science degree in geology from the College of William and Mary, Williamsburg, Virginia.