Name: Sara Kahanamoku
Hometown: Haleʻiwa, Hawaiʻi
Department: Integrative biology at UC Berkeley
Research topic: Photographing ocean cores and fossils to understand patterns in ecosystems through time.
Growing up on the North Shore of O’ahu, Sara Kahanamoku says her connection to the ocean has driven a lot of the decisions she’s made in her life. Her parents were often at work and she didn’t have any siblings, so she spent a lot of time swimming and surfing and diving — the way she tells it, “just checking out the world.”
Spending so much time in the water, she always had questions: How did everything get here, and how long has it been this way? She wondered what the islands around her looked like 100 years ago, or one million years ago. And she would sit on the beach, watching the ocean and the mountains, and come up with stories to explain everything.
Several years later, she stumbled into a paleontology class at Yale and started to actually find the answers to all of those questions she’d had as a kid. When she graduated, she still had questions, so she decided to go to graduate school.
“I’m Kanaka Maoli; I’m Native Hawaiian,” Sara says, in the midst of telling me how she arrived in the small lab room she’s sitting in as we talk. “[My research interests] came from spending years sitting on the beach and looking at the water … The story of my graduate school career is trying to figure out how to … honor that part of me while being here.”
We skip back through time as she tells me about her first job as an undergraduate in a microfossil paleontology lab washing out ocean cores — the physical records of an ocean’s history obtained by drilling down into the sea floor.
“Imagine sticking a straw into a layer cake and pulling it up [so] you can see all the layers,” Sara explains to me. “It’s kind of the same idea. But when you pull up those cores, they are full of clay and dirt, so you have to wash them out.”
I start to tell her how much I enjoyed the analogy, but we’re already whizzing through an explanation of what all the layers mean.
Once the cores are clean, Sara says, they provide chronological data of the presence of carbon in the ocean or of the Earth’s magnetization, among other things, sometimes going back thousands of years. Depending on where the core is pulled from, though, these records can have various resolutions — meaning that sometimes each layer in the sample represents a year, sometimes only a day or a minute, and sometimes each layer accounts for thousands of years in and of itself.
When Sara arrived at graduate school, she really wanted to work with cores that provided an annual record — and a recent one, too. She tells me this and then laughs to herself, recounting the years she spent coming up with the idea for her thesis, and then the months after that it took to find the right sample location off the coast of North America in the Santa Barbara Basin. It’s a place deep enough and with enough upwelling due to tectonic shifts to be anoxic, or depleted in oxygen, and therefore preserve all the material washed in and the lifeforms living on the seafloor really well. Then it was another eight months until she even got those cores delivered to her.
“The day that I got them and I was handed these boxes in [a] 110 degree parking lot in Southern California, I [thought], ‘Oh, thank God, they’re finally here,’ ” Sara says. “I opened them and I was like, ‘Oh, wow, this is amazing’ because, you know, [I could] see they were already washed, so somebody else, thankfully, had sprayed them with water and [gotten] all the dirt out.”
Cleaned and placed into individual little vials, these core samples were labeled by year from 2010 all the way back to 30 A.D. To Sara though, the most valuable years were from the 1840s on — a period of time that spans a lot of environmental change, she tells me.
“We can look at what happens off the coast of California as you get increasing pressures from [the] expansion of colonialism, industrialization and … fishing pressures,” Sara says. “Also anthropogenic climate change.”
Anthropogenic impacts on the Earth are what we cause as humans, like global warming, mass extinction or biodiversity loss, ocean acidification, habitat encroachment and ecological collapse.
To figure out how all of these changes are affecting the ocean community, Sara studies benthic foraminifera, which are unicellular organisms that form shells which embed themselves in the fossil record. These organisms live on the seafloor or at the ocean’s surface and create their shells in equilibrium with sea water, so their fossils inherently contain a record of all the chemicals present in the ocean at the time they were alive.
In addition to informing our understanding of ecosystem changes, Sara tells me, these fossilized shells can also help us decode life history changes — how individual choices made by these foraminifera over the course of their growing and reproducing and dying have changed throughout time. In a particular set of species, the shape of the shell records whether the individual reproduced sexually or asexually, or not at all.
Sara tells me she’s figured out that, over the years, these tiny organisms actually do change how they reproduce, and now she just has to figure out why.
“[Benthic foraminifera] are very well represented in the fossil record, but … we don’t know a lot about their biology — we’re piecing it together,” Sara says. “We’re trying to understand … if [their reproduction] is correlated with environmental pressures or [if] it’s a cyclical thing, or maybe it is … correlated with human impacts on land.”
As Sara is explaining all of this to me, I interject and say something about how amazing it is that you can tell all this from these tiny little fossils. I must gesture with my hands while I say this, squeezing my fingers together to mark out a half an inch, because Sara jumps back in to correct me.
“Oh,” she says. “They’re tiny … like maybe 100 microns wide.”
I look up how big 100 microns is later, just to get an idea. It’s the width of a piece of paper, or a strand of hair.
“That’s why I’m literally always on the microscope. I think that’s why I need glasses now, too,” Sara adds, offering a shrug and a laugh.
I ask her what it’s like to do this work day to day and she describes the microscope she uses and the tiny paint brush needed to sort out the fossils.
“There’s a bunch of stuff that washes [into the cores] from the upper water column — like plankton … fish scales from fish that are swimming around … fish teeth and bones, or even shark scales in some cases. So … I need to go through and pick out the ones that I’m actually interested in,” Sara says. “That’s what I do most of the day: just sit at a microscope with a paintbrush and pick up individual grains of tiny sand, which are [actually] fossils.”
Then Sara says she has to take a picture of everything using a 3D imaging microscope and categorize all the individual fossils by shape and size.
“Honestly, most of it is super rote. I watch a lot of Netflix — well, ‘watch,’ ” Sara says, miming air quotes. “I listen to a lot of Netflix while I’m at the microscope.”
We talk about her favorite TV show for a while (“Schitt’s Creek”), and I add it to my growing list of recommendations. She tells me that she was hesitant at first to watch a show about a rich, white family, but she found it strangely futuristic for a sitcom. I wonder to myself why that made it stand out to her, but she’s already in the middle of answering my unspoken question.
“I would say ‘Star Trek’ [is my favorite show] — my partner and I are obsessed with ‘Deep Space Nine,’ ” Sara tells me. “But I’m not allowed to watch it when he’s not here.”
We laugh about that for a minute, and she tells me a little bit more about her partner, a graduate student at UC Berkeley, too, who’s studying physics. And then she brings up the Thirty Meter Telescope, which she calls the TMT.
“There’s a plaque in the astronomy building about how TMT is the next big innovation,” Sara says. “I would go there for social hour and tape a piece of paper over the plaque — like you want me to be here and be enjoying myself while I know the billions of dollars that you’re funneling into this project that would run my friends over to get their construction equipment up the mountain?”
We talk about this for a long time, because I’m a former astrophysics major who spent years feeling frustrated that the department faculty wouldn’t acknowledge that this so-called exciting new project was slated to be built on Mauna Kea’s sacred land belonging to indigenous people. And Sara’s a Native Hawaiian who’s spent years writing op-eds and participating in the movement to protect her home.
She tells me that the university’s silence on this issue is, in part, what has made her not want to be a professor anymore; that in some senses, deciding that was kind of freeing.
“It was weird because [working to protect Mauna Kea] defined my life and changed me so much in so many ways. And it was something that the folks in my institution didn’t really notice,” she says. “On occasion, I’ll get comments here and there that [are] like, ‘Why are you spending so much time on this?’ Or, you know, ‘Is the mountain really that sacred?’ ”
Sara confides to me that when she first arrived at graduate school as a first generation student, she thought it would be a place for openness and discovery, somewhere to finally finish answering her childhood questions.
“And in some sense, it is,” Sara tells me. “But I think that it’s not that way if you are not white … I would love it if people were less surprised when I [say], ‘Yes, I’m Hawaiian and I am a scientist and I’m doing my PhD.’ I think there’s a lot of stereotypes about what a scientist looks like — which you clearly know.”
I nod. Sara adds that we bring our cultures and our experiences into how we ask questions and gather data and come up with explanations.
“I bring my culture into my science,” she says. “And my culture makes my science better.”
Sara’s relationship with her land is the reason she’s struggled to get people to understand the impacts of the Thirty Meter Telescope and the sovereignty of Hawaiʻi. And her connection to the ocean is what drives her research.
“I think that a lot of what scientists … in academia now have been trained to do doesn’t hinge on being in good relationships with people. Being a good relation is one of the core tenants of a lot of indigenous cultures,” Sara says. “Something that I sincerely hope that we as scientists start to develop more and grow more is our responsibility to people.”
It’s after Sara says this that I understand something she said nearly an hour before. As she talked about her connection to the ocean, I had thought she’d meant that in the way people say they’re attached to a particular place, maybe a city they grew up in or the restaurant where they had their first date with the person they would later marry. Or maybe she’d meant it in the way people feel compelled to do some kind of work, I’d thought at another point — that her memories of the ocean are what led her to become a paleoecologist.
But Sara has a relationship with the ocean, the way we do with people we love. To her, “the ocean is like a third parent.”