Lucinda Duxbury’s favourite place is onboard the research vessel (RV) JOIDES Resolution. She’s seeking traces of ancient DNA within Arctic sediments. This article was originally published in the Cosmos Print Magazine, March 2025.
My favourite place isn’t a fixed location in space.
My favourite place is aboard a research vessel that sails the 7 seas to drill down into the soft sediments lying at the bottom of the ocean. Contained in the mud are traces of past climates and environments, laid down over millions of years.
When we analyse these traces, they offer a portal into Earth’s past. And, if we pinpoint particular time periods, they’re a muddy window into a warmer future.
Into the floating lab
I’m in the far corner of the microbiology lab, dressed head to toe in a white suit, mask and safety glasses. All you can see are my eyes.
Right now, I’m focused on the task at hand. I’m cutting off the tips of hundreds of sterile plastic syringes so we can plunge them into the kilometres of fresh sediment cores we unearth from the seafloor.
Cut, clean, bag, seal, rinse, repeat. It’s monotonous but I’m leaning into it. Repeat, repeat. Repeat like the past repeats. It feels like a form of meditation.
I leave the lab and look through the window to the world outside. Svalbard’s snow-capped fjords to one side of us, sea ice to the other.
We’re well past the Arctic Circle now. Into the fog and into the thick of it. A sea of ice, whales, porpoises and puffins.
The concept of time is slippery under an unrelenting midnight sun. If you think about it, the Arctic summer is just one big, long day (with lots of naps in between).
I imagine it should be peaceful here. But we come in a loud diesel-powered boat bearing news of an ice-cracking climate crisis.
For 2 months, a shipload of scientific minds whir around the clock. Geological time blurs as we haul up rock dropped millions of years ago from the melting icebergs of ancient ice sheet retreat.
I’ve come all the way from Tasmania, an island falling off the bottom of the world.
I’ve never been this far north. But in this closed-off clean corner of the ship, I sometimes forget it.
The flow of heat
We’re about to arrive at our first drill site. Our journey on this expedition will track the path of the West Spitsbergen Current into the Arctic Ocean. The current acts as the main way heat from the warmer lower latitudes is transported to the deep north.
We’re collecting sediment cores that will help us understand how this heat source has interacted with Arctic ice, atmosphere and ocean through time. What happens with heat flow into the Arctic affects the global system.
For example, increases in meltwater can slow overturning ocean currents, with dramatic effects for northern hemisphere climate. If we study this system in the past – especially during times of elevated temperatures and CO2 – we might be able to glimpse into our future.
Traces of DNA
The excitement as we start drilling on the first site is palpable. An international goliath effort has gone into just getting us to the point where we can begin.
It’s like Christmas Eve. I can’t sleep so I write little poems to pass the time. We play the epic and dramatic song ‘Ecstasy of Gold’ on the loudspeakers to welcome our first sediment core on deck. I’m ready in my white suit, gloves, mask and glasses – sterile syringes in hand.
There are secrets in the sediments. I’m looking for ancient DNA in my samples, potentially millions of years old, to reconstruct traces of past ecosystems.
The DNA is so degraded and broken down, we must go to extreme lengths to protect it from contamination from modern, intact DNA that would drown out the ancient signal. That’s why I’m wearing all this protective gear. We don’t have to protect ourselves from the samples, we must protect the samples from us.
Back on land we will sequence this DNA, generating gigabytes and gigabytes of genetic code. We will compare our data to a reference database of known genetic sequences to work out what phytoplankton and zooplankton made up the marine ecosystem when the Arctic was ice free in the past.
Marine microorganisms such as plankton form the base of entire food chains. They affect the cycling of greenhouse gases including carbon dioxide through the Earth system. Understanding the composition of these past communities has huge implications for Earth’s future.
Earth poetry itself
After a few weeks we settle into the routine of life on the ship. I go to bed knowing I may be woken up at any hour if we start drilling a new hole.
For 2 mad months we give ourselves permission to be totally absorbed by our science. With this comes a communal depth of knowledge made possible only by circumstance and this ship.
Sometimes, though, the glitz and glimmer wear off and our patience with each other wears thin. What was once shiny shows its true colours – and it’s the uninspiring hue of green–brown mud.
Through these moments I cling to the words of the great marine biologist Rachel Carson: “The sediments are a sort of epic poem of the earth.” Downwards we dive into the tremulous echoes of the past.
Sometimes when I’m in my cabin trying to sleep, the low grumbles and creaks of the ship could almost be mistaken for the heave, groan and grating of the ancient ice sheet herself – to the beat of the climate cycles. Her echoes we bring to life with X-rays and smear slides.
Until the end
We’re being chased south by ice now. Our ship is not an icebreaker so whatever move she makes, we acquiesce.
Under the harsh light of an Arctic summer, her twilight draws closer. The Intergovernmental Panel on Climate Change (IPCC) predicts with high confidence that we will experience at least one ice-free Arctic summer by 2050.
Then, one day, the expedition is over.
Where we once watched a live cam of the drill floor, we stream the skateboarding at the Olympics.
Soon enough we’re back in busy shipping lanes. Back in shorts.
Night, too, returns. Out on deck a group gathers to watch for the first time, in a very long time, as the sun slips unceremoniously below the horizon. It signals a welcome restoration of balance in our lives.
This was the final expedition for the RV JOIDES Resolution. After decades of service to the science community, the ship herself is an archive of story and adventure. As you read this, her labs have already been dismantled. But she won’t be fully gone for a long time.
The JR will have a half-life in our memories of far-off places and times, in the moments that become enshrined in legend as they are retold and reremembered, at times misremembered. Stories from the people that worked and lived together – beautifully and messily – to uncover oceanic secrets.