There is a kind of terror-tinged embarrassment that comes from dozing off on your beach towel on the sand, only to find a rising tide intrude upon your mid-nap bliss, lapping at your toes and sweeping away your sunglasses.

It is a truth I relearn every June, one that arrives like the season’s first sunburn: The ocean is inevitable, and Poseidon always reclaims his own. Actor Nicolas Cage learned a far more serious — or more expensive, certainly — version of that lesson earlier this month, when a furious high surf siphoned the ground beneath his Malibu, California, mansion, collapsing his driveway and front porch into a gigantic 30-foot-by-30-foot sinkhole. The cave-in ruptured a gas main, swallowed an access road, and forced dozens of locals to evacuate. In the process, it put into stark, cinematic relief the unyielding threat of coastal erosion in every community in the nation with a view of the sea.

It’s impossible not to imagine Cage standing on the edge of that yawning pit as he might in one of his films, bombastic in his bafflement, every outsize gesture a pantomime of confusion. But no one should have been surprised. As far back as 1976, the California Coastal Commission denied a proposal to build a home on the lot where Cage’s Malibu home now teeters over the void, citing “concerns over wave hazards.” In 1986, the same commission rejected another residential proposal on the land, deeming it an “extremely hazardous area” threatened by waves and erosion. 

So why, just a few years later, was a home built there anyway, one that would eventually come to be owned by a certain Hollywood eccentric? A few years after their initial rejections, the waterfront lot’s original owners were able to convince the commission that with enough clever engineering, including a sea wall and concrete stilts, the home, its septic system, driveway, and access road could be protected from the sea god’s wrath. But much like Odysseus before him, Cage has found the hard way that the lord of waves does not easily forget his due. “What is the Grail but Earth itself?” he once told the New York Times, characteristically mythologizing his real estate acquisitions. “The divine object is Earth.”

In this case, at least, Cage chose the wrong cup. But Cage is hardly alone in laying out his home atop the wrong stretch of sand. Nearly all of the nation’s coastal communities — from ritzy enclaves like Malibu to working-class quarters of the Rockaways in New York — rely on coastal engineering to remain inhabitable, dumping sand or erecting sea walls to put off a perpetually and increasingly rising tide. 

To put this into perspective, almost one-third of Americans live along a coastline, and while few of us have the kind of luxury oceanfront views that Cage and his neighbors enjoy, our beachside apartment complexes, utility lines, and coastal highways suffer from the same risks his driveway does. Most of us, however, lack the benefit of a second home or a private island to flee to if something goes catastrophically wrong. 

When a sinkhole opens underneath a celebrity’s driveway, or a stilted home collapses into the sea, it is a reminder that we have built huge swaths of our beloved coastal communities on land that was never meant to sit still. If we want them to survive, we will need to learn to embrace new ways of packing our beach towns up and wheeling them further upshore. Logistically implausible as it may sound — difficult as, say, stealing the Declaration of Independence — it’s a process that several American communities have become much better at in recent years. 

“This is not a problem that is unique to Malibu, which just so happens to be some of the most spectacularly beautiful and spectacularly expensive real estate in America,” said Kara Murphy Schlichting, an environmental historian at Queens College in NYC. “This is a question that is coming for all of America’s coastal communities.”

Say it ain’t sinkhole

The void that swallowed Cage’s driveway with the gusto of the actor chewing scenery in one of his films was no ordinary sinkhole. In fact, if you asked a geologist, they would tell you that it was not, technically speaking, a true sinkhole at all. 

“It’s not what I typically would consider a sinkhole,” Michael Sukop, a hydrogeology professor at Florida International University, told me. That’s because most sinkholes form when rainwater or a leaky pipe slowly seeps into the porous bedrock beneath our highways, homes, and soccer fields, creating a cavern that screeches open during a heavy downpour or when the infrastructure above it becomes too heavy to bear. 

There is no accurate accounting of every sinkhole in the US, but geologists widely believe that they have become more frequent globally, driven by extreme weather linked to climate change, aging infrastructure, and what Sukop calls “people moving into sinkhole country,” meaning places like Florida where the bedrock is highly soluble. Some of the worst places for sinkholes in the country are in landlocked states like Missouri, whose unique landscape boasts upward of 16,000 sinkholes, which often open after heavy rainfall.   

But Cage’s sinkhole was formed not from hidden cavities in the bedrock, but from a high surf strong enough to slip under his sea wall and wash away the soggy soil beneath his asphalt and, presumably, his Rolls-Royce Phantoms. It was spurred not by rainfall or a leaky pipe but by a tidal force akin to the one that can put a damper on — or literally dampen, anyway — a beach spot that seemed perfectly sandy when the surf was low. 

@accuweather

A homeowner on North Carolina’s Outer Banks paid to move their beachfront home away from the shore to prevent it from collapsing into the ocean, as several neighboring homes have.

♬ original sound – AccuWeather

But while I can learn to lug my sodden towel and cooler a little further upshore, the same cannot easily be said for Cage’s $10.5 million abode, built — like much of Malibu — atop a constantly shifting coastline. Which isn’t to say that it wouldn’t be a good idea to try.

“It’s a fiction that we can keep a coast in a single place,” said Schlichting. And it is a fiction upheld by hundreds of millions of dollars spent each year on temporary solutions meant to hold the ocean still, and protect the luxury homes and boardwalks we’ve built along it. 

The pristine, sandy beaches that most of us think of when we think of the word “beach” are often heavily manufactured for our pleasure, much like an urban park might be seeded with carefully cultivated trees and brush. In fact, the federal government spends hundreds of millions of dollars each year to dump sand atop eroded coastlines, a process known as beach renourishment, in addition to many more billions spent on sea walls and other structures that can keep a coastline in place for a little while. 

“The most endangered species on the coast is not a turtle or a piping plover; it’s an unengineered beach,” said Robert Young, director of the Program for the Study of Developed Shorelines, who has been tracking beach renourishment projects since the 1980s. “And it’s unsustainable because as sea level continues to rise, we are having to pump that sand more and more frequently.”

How to save coastal neighborhoods

Earlier this year, Malibu released a long-awaited Coastal Vulnerability Assessment that twice called out the acute dangers that erosion poses for Sea Level Drive, a small stretch of private road, upon which a gaping crater now sits where Nicolas Cage’s driveway used to be. As this year’s goliath El Niño gets into full swing, his misfortune is unlikely to be the city’s last. 

Already, the spectacular seafront Pacific Coast Highway faces a gauntlet of exigencies, among them landslides, wildfires, and, of course, a coastline that simply won’t sit still, creeping further and further inland each year. Just this weekend, officials in Malibu issued a warning about hazardous conditions at local beaches, with “severe beach erosion” exposing steel and concrete debris sticking across the coastline.  

“Nature itself does not destroy the coast. It moves the coast,” said Young, but if infrastructure like the Pacific Coast Highway lies in the way of that movement, then there is only so much that building a sea wall or dumping 300,000 cubic yards of sand every five years will do. “No matter where you are, whether you are in California or South Carolina or New Jersey, we are still building in dumb places.”

Much like laying a log in front of your beach towel won’t hold the tide back for very long, these measures are often only a temporary balm. But there is another way, one that involves moving the proverbial towel — or permanent infrastructure — away from the shore, a process known as managed retreat.

As implausible as it may sound, when you take into account just how much money has gone into keeping the coast still, lugging a few celebrity mansions, a beachside school, or a sliver of highway across town might be a Herculean labor worth attempting. 

“It’s totally doable,” said Young. “We can move just about everything.” On the coast of North Carolina, the Cape Hatteras Lighthouse, one of the tallest brick lighthouses in the world, was moved in 1999, a feat that Young helped pull off. At the time, he said, locals  “wanted to shoot us over” the effort, sure that the centuries-old structure would fall down. “And you know what? It’s safe now,” he said, noting that just down the beach in Buxton and in nearby Rodanthe, dozens of homes have collapsed into the ocean since 2020.

But even in places where such coastal relocations were once commonplace, it’s still not an easy sell for most coastal policymakers and their constituents, especially in places like Malibu, whose density and geography make it all but impossible to move things nearby. But sooner or later, they might not have a choice. 

“I can’t tell you how many coastal elected officials have said to me, ‘Rob, you know, retreat is not an option from this place.’ And I’m like, well, actually, you are retreating here, here, here, and here,” Young told me. “It’s just you’re doing it in the worst way possible. You’ve got septic tanks rolling around in the sea. That is not a great Chamber of Commerce moment.”

Wildfires are popularly considered wild — restricted to the remote wilderness or the edge of forests, and to most, a problem for the dry and hot states of the Western US. But over the past few years, and now across the country, these fires are getting less wild and far more urban. 

This summer, fires in Spokane, Washington, demolished over 800 homes in a suburban neighborhood, and earlier in the season, the northeast coast was engulfed in smog from fires in Ontario. The Hawk Fire in Nevada razed more than 15,000 acres near Reno, destroying 47 homes before it was extinguished. The Los Angeles fires of last year remain some of the most devastating in recent memory, with over 37,000 acres burned — much of it densely built residential neighborhoods — and displacing 205,000 people from their homes. In Boulder, Colorado, the 2021 Marshall Fire destroyed nearly 1,000 homes. 

This changing geography of fires is affecting the health risks they present, too. 

When vegetation burns, it releases particulate matter, or PM 2.5, and with over 46 million homes in the continental US — this is approximately one-third of all homes — on the edge of fire-prone wildland, many more of us are being exposed to air filled with that soot. This alone is a major health risk. According to the World Health Organization, PM 2.5, is associated with premature death, severe damage to respiratory health, and cognitive impairment. It is especially dangerous for aging populations: a study published in February found that accumulated exposure to wildland smoke was associated with greater hospitalization risk for various cardiovascular diseases in older Americans, including irregular heart rhythms and heart failure, even when they are only exposed to moderate levels of PM 2.5.   

But the urban landscape has also changed the very composition of the smoke that increasingly hangs over all of us. As human structures and vehicles burn, the fires expose us not just to particulate matter but also to the chemical toxins of urbanization itself, from plastic to metal oxides and vehicle fuel. The changing nature of this smoke, in fire zones but also in surrounding regions as it drifts outward, exposes us to a new class of health risks. 

While researchers are still learning what exactly those risks might entail, early research suggests long-term dangers that are deeply troubling, especially as exposed populations age.   

The changing fire frontier 

In 2020, the worst California fire year on record, ate up 4.2 million acres of land, most of it wild, spewing huge amounts of PM 2.5 into the air as the blazes raged. Emergency rooms, already short-staffed by the ongoing pandemic, buckled under the burden immediately. Northern California’s Stanford Health Care system saw a 12 percent jump in hospital admissions over the weeks following the fires, and a 43 percent increase in cardiovascular conditions. In Oregon that same year, 10 percent of emergency room visits were due to asthma-like conditions induced by smoke as fires migrated north.  

Unfortunately, in a world of warming temperatures and drying conditions, that story is becoming all too common. In 2025, a total of 5.2 million acres of land burned across the US, and this year that number has already climbed to 8.5 million, before we’ve even hit the winter dry seasons that plague parts of the Southwest. 

Despite this, the global footprint of human housing continues to expand, and with it the danger.  

For centuries, human development has breached wildfire territory. However, over the last three decades, the zone that links the wild to cities and towns, called the wildland-urban interface (WUI), has grown substantially due to suburban construction. The US Forest Service found a 46 percent increase in the number of houses in the risky WUI zone between 1990 and 2020. By 2020, a third of US homes had been built in this highly vulnerable landscape. The math is simple: As suburbia expands into wilder regions, the more houses are exposed to wildland, and the fire risk grows greater. And when houses and other human-made goods burn, different and potentially more toxic forms of smoke can be produced. 

The Los Angeles County fires in January 2025, which saw large urban regions devastated by flames, were an unfortunate case study for these risks. The Palisades and Eaton fires began on the northern edge of the LA foothills, where dense housing meets more wild, and more fire-prone, terrain. In a retrospective analysis, Underwriters Laboratories’ Fire Safety Research Institute detailed how the urban-wildland makeup of Los Angeles County has not only put more communities physically in fire-prone zones, but also has historically made the geographic region itself more vulnerable to fires. 

As those fires spread into LA’s more urban areas in 2025, the smoke they produced became more dangerous, largely because of what was burning: more than 16,000 buildings, household items, and electric vehicles. The resulting emissions were thus far more complex than typical vegetation-only fires. 

“What’s burning is now very different,” said Jackie Goodrich, an epidemiology professor at the University of Michigan. “So now modern homes have tons of plastic, metals, and all of our electronic appliances, and electric vehicles have these batteries that have a lot of rare metals and other toxic materials we don’t even know about.” 

As a result, these emissions contain higher concentrations of volatile organic compounds (VOCs), metals, and carbon monoxide. PFAS, commonly dubbed “forever chemicals,” are also released through fire extinguishing foam and damaged firefighting gear, which traditionally contains PFAS to protect the skin from fuel that may soak through. These chemicals are associated with adverse health effects, including higher risk of certain cancers and weakening of the immune system. Many of these compounds are dangerous carcinogens. 

These urban fires have a dangerous impact on indoor air quality, too, as chemicals and metals are absorbed into soft surfaces like pillows or textiles. Studies conducted in the aftermath of the LA fires found that post-wildfire VOC levels were elevated inside evacuated homes during the months following the fires. All of this goes to show that Americans can face the health risks of WUI smoke exposure, even when their homes emerge from the blaze relatively undamaged.

These dangers mount over time and across populations

Studies examining hospital admission rates or emergency room visits offer some perspective on the short-term health effects of wildfires. But work by Goodrich and University of Arizona public health professor Jeff Burgess is providing new insight into long-term harm by using a subset of the population repeatedly exposed to and vulnerable to fires: the people who fight them. 

In a study published last year, Goodrich and her fellow researchers examined blood samples from fire responders working in mixed urban and wild areas. They found that exposure to smoke limited the genetic expression of a tumor suppressor known to inhibit gastric cancer cell growth. It also affected regulatory expression similarly associated with tumor proliferation across cancer types, as well as neurodegenerative diseases. 

Burgess has run similar studies across 33 states with 9,000 participating firefighters, allowing the researchers to examine changes in microRNA levels, blood proteins, and DNA methylation (which controls whether genes are on or off). His research on a small cohort of new fire recruits found altered DNA methylation at various sites in the genome, many of which are similarly linked to cancers, neurological disease, and cardiovascular disease. 

It is still unclear whether these biological warning signs lead directly to cancer, Burgess said, largely due to the natural latency period between exposure to toxic substances and actual onset of disease. But as participants age, he expects to see a higher incidence of cancer, especially as exposure to big fires accumulates. 

Firefighters have more prolonged exposure to these toxins than most, of course. But the health effects of wildland-urban fires can extend beyond self-selecting groups, especially as more people move into regions exposed to fire. Residents in the WUI are exposed to the same particulate matter and chemical slurry as firefighters. Goodrich suggests that this could lead to a higher risk of asthma and respiratory problems for children, as well as cardiovascular health incidents in adults.  

Examining longer-term gene expression effects, however, is still more difficult in the general population than it is in the firefighters that her lab studies. While firefighters are often exposed to the same chemicals over and over again, it can be harder to get a clear sense of how toxins affect the average civilian who encounters them more sporadically. 

That said, researchers at UCLA have been keeping a close eye on background toxic chemicals in the aftermath of the LA fires. In a paper published in June, they identified high levels of chromium 6, a carcinogenic metal nanoparticle that can cross cell membranes easily, in wildfire cleanup zones for up to two months following the actual fire. Abnormal concentrations of these heavy metals were also found up to six to nine miles downwind from the zones themselves.

Even following the disaster and immediate recovery periods of urban destruction, the public health dangers can persist: Toxic compounds like VOCs can contaminate waterways, and damaged air filtration systems can make it harder to protect surviving homes against future incidents.

As wildfires become less confined to the chaparral and forests and more likely to rage through suburban streets, we’ll all have to prepare to face the orange haze of fire season. And as we do, we’ll have to confront new dangers that may persist long after the blaze dies down.

This story was originally published in The Highlight. To get access to member-exclusive stories like this every month, become a Vox Member today.

PALAU, Micronesia — On a bright, sunny day last May, I stood on a boat surrounded by the turquoise waters of the island nation of Palau. I was there in the western Pacific watching scuba divers as they prepared to bring up evidence of a mysterious aquatic world. 

Palau is famous for its spectacular and rich coral reefs. But these divers were planning to descend past those sun-lit marine communities and down into a lesser-known twilight zone known as the “mesophotic coral ecosystems.” 

Mesophotic essentially means “middle” and “light,” which is where these ecosystems are — not quite in the bright daylight, not quite in the profound darkness, but somewhere in between. For simplicity’s sake, we’ll call these communities, which range from some 30 meters to 150 meters below the surface, the “deep reefs.” 

One of the divers on the boat with me was a zoologist and curator at the California Academy of Sciences named Luiz Rocha, who has spent decades studying these deep reefs and their secrets. 

“Anything between 30 meters and 150 meters is really, really unknown,” he told me.

Because these deep reefs are so unknown, researchers like Rocha are left with big questions. They want to get a baseline picture of what is going on in these ecosystems — even just who lives there! — so that they can better understand how they function.  They’ve also tried to work out whether (or not) these deep reefs might provide a refuge for species living in shallower coral reefs.

I was in Palau for Vox’s Unexplainable podcast because, in an effort to gather more information about these mysterious places, Rocha left some scientific structures down in these twilight depths back in 2016. Those structures then spent almost a decade becoming encrusted with all kinds of marine life. And now, Rocha was back to retrieve them, hoping that he — along with many other scientists — would be able to open them up, like a box of scientific puzzle pieces, full of clues about this under-understood marine world.

So what is a mesophotic “deep reef”? 

One thing that’s often acknowledged in papers about and descriptions of the “mesophotic coral ecosystems” is that scientists don’t know as much as they’d like to. A National Oceanic and Atmospheric Administration article about them from 2019 is full of “may’s” as in: they may “serve as essential fish habitat for economically and ecologically important species.”

Researchers do know some things, of course. They know that these deep reefs can be found in many of the same locations as shallower coral reefs — so mainly the tropical and subtropical parts of the world, like Micronesia, the Caribbean, and even the Gulf of Mexico. They’ve found that there are many species that seem to be unique to these places, and recent research points to their potential susceptibility to climate change.

Researchers have also gotten a sense of some of the key differences between these deep reefs and their shallower coral neighbors. In shallow reefs, hard corals team up with photosynthesizing algaes. The algaes provide the corals with nutrients, and the corals secrete a calcium-carbonate matrix that helps create the architecture of the reef. 

As you go deeper, though, the light begins to fade, and the opportunities for photosynthesis start to fade with it. The temperature also drops. So the animals living down in the deep reefs are the ones that can survive in a dimmer, cooler world.

Why are these places so mysterious? 

Scientists can dive into the deep reefs to try to learn more about these understudied places — as Rocha has — but exploring down at 100 meters requires more difficult, riskier technical diving than exploring at shallower depths. The deeper you dive, for example, the faster gasses get pushed into your tissues, which imposes limits on these really deep dives.

“We have a very, very short time,” Rocha says, “And by short time, I mean five minutes. Six, seven minutes.” 

Scientists might take some pictures in that time, or make some measurements, or collect a few samples, but then they have to move back upwards, a process which can take hours because they have to rise slowly to avoid decompression sickness.

It is, obviously, not particularly efficient to study an ecosystem in five- to seven-minute bursts. People have also used remote operated vehicles and submersibles to explore the deep reefs, but those have their own issues, and cameras can’t always capture all the detail you might want, or photograph more secretive, cryptic animals. So huge gaps remain in scientific knowledge about these ecosystems. 

“Whenever we go somewhere,” Rocha says, “the first thing we find is new species. … It’s the most basic thing in science you can do.” But this effort goes beyond just cataloguing new species of fish or sponges or sea slugs. 

Rocha wants to answer seemingly fundamental questions like: What is the main energy source for everything down here in the dimmer light? What does the food chain look like? How have things evolved to live down at these depths? How similar are they to the shallow ecosystems, and how different? How are they affected by climate change — and what’s the most efficient way to protect them? 

But, “in some ways we don’t even know what questions to ask,” Rocha says. “We really only know what questions to ask after we have a baseline understanding of what the ecosystem is. And for deep reefs, we don’t know that yet.” 

A new way to understand the deep reefs using “prefab housing”

Rocha is not deterred by the enormous number of question marks that surround these deep reefs. For years now, he has been gathering bits of basic information about them, often via those very short dives. 

About a decade ago, though, Rocha got interested in another method for sampling the biodiversity of this sort of marine ecosystem — a technique involving “autonomous reef monitoring structures” (ARMS).

Basically, each ARMS is a stack of several PVC plates, separated at uniform intervals and attached to a base plate. They look like little grey, featureless hotels. You take them to a place that you want to study, bring them down, secure them, and then leave them alone for a while to let them collect…life.

“As soon as you drop any kind of clean structure on a reef,” Rocha says, “it starts getting colonized by larvae of everything around it — of sponges, gorgonians, corals. And then, because there’s all a lot of hiding spots between the plates — so between the floors of the hotel — they start getting colonized by shrimp, by mollusks, by ascidians, by anything you can imagine in the ocean. … And it becomes this stable, diverse mini reef, if you will, packed with a lot of biodiversity that would be very hard to collect all at once in any given reef.”

A few years after that initial drop, you come back, collect the ARMS, and then study the mini reef that has grown on them. You can sample and touch and analyze things to your heart’s content. 

It’s not only a very effective way to collect lots of creatures, all at once, but also a great way to do so in a standardized way. If you went down — or sent a robot down — to collect an encrusted rock from a reef, you could learn a lot about the life on it, but it would be hard to compare the life on that rock to life on other rocks from other reefs, or even the same reef, because each rock would have its own unique characteristics. Not so for ARMS.

“ Every one’s the same,” Chris Meyer, director of the Smithsonian Global ARMS program, told me, “It’s prefab housing, and then you just look to see who moves in.” 

To Rocha, this seemed like a great way to get a really good, long look at the deep reefs instead of the brief glimpses he was getting from diving. It was also, he told me, fairly cheap to deploy them. So from 2016 to 2018, with some private funding, he and his colleagues left ARMS in some of the deep reefs around Palau — as well as in Guam, the Marshall Islands, and French Polynesia. They installed some around 50 meters, and some around 100, and then some around 10 meters, so he could compare the deep reefs to their shallower neighbors. 

After that, he waited. 

In fact, he waited a little longer than he would have liked, because the retrieval of ARMS is more expensive than deploying them, so he had to work out more funding. 

Eventually, private funders agreed to underwrite the retrieval of the ARMS that Rocha had left. Which is how he and his fellow divers finally found themselves on a boat in Palau again, ready to pull up these structures for the deep.

Opening the scientific puzzle box

Over the course of a few days, I watched a whole team of people pull several ARMS out of the deep reefs of Palau. Some of the ARMS were relatively sparse, but others were almost fuzzy with organisms — vibrant with red and orange and green and pink and white. One had a massive sponge attached to it, another had several delicate fronds dangling from it like coralline ferns. The ARMS collected each day traveled to the Palau International Coral Reef Center in bins full of seawater, where the scientists quickly got to work — seeing and touching (and smelling) this mysterious ecosystem right up close.

The process was, as it turned out, equal parts magical excitement and well-oiled, Cheez-It fueled disassembly line. After the plates were taken apart, Meyer took photographs of the plates — what he called a “time capsule of the place.” Others in the lab picked carefully through trays of debris, hunting for tiny crabs and worms and mollusks, or scraped samples off the plates and deposited them in tubes.

They collected sea squirts, said to be our closest invertebrate relatives. They collected sponges — flat ones that felt dry underwater, thick ones with bristles like tiny, unmoving caterpillars, one as thin as a flake of skin and shot through with silver filaments. They collected strange, soft corals known as “octocorals,” and they collected colonies of animals called bryozoans, which created what looked like swirling, two-dimensional honeycombs.

“We’re looking for every unique thing, which we call a morphospecies,” a Smithsonian research biologist named Sarah Tweedt explained. “And we’re trying to get some representative tissue samples from all of these things so that we can sequence the DNA — and match the DNA to the organism.”

That is, of course, assuming there is already a known genetic match in our existing DNA libraries. 

On the first day that I spent with the team, a Cal Academy curator named Terry Goslinger identified several potential new species. He is an expert on colorful, delightful sea slugs known as nudibranchs, and so, because of his deep knowledge (and because nudibranchs’ bright hues and patterns make them somewhat easier to tell apart than some other underwater creatures), he was able to make some on-the-spot calls about whether or not certain species were likely to be new to science, pending genetic testing to confirm.

Many of the animals were trickier to pin down, though. The researchers did their best to identify the creatures they were finding, but even now, several months out, there’s still a lot of work to be done. Of the close to 3,000 specimens, only a small fraction were identified at a species level. The numbers are a little bit inexact because researchers are still processing the data, but when I checked in with a Cal Academy postdoc working on the project, Susanne Bähr, in July, she told me that only 3 percent of samples had been ID’d by species, and a little less than 20 had a genus designation. Many, many more were only identified at higher, broader taxonomic levels. Genetic testing of the samples, paired with photographs and descriptions of the samples, will help people work out more specific species, and also help them identify whether certain species are new to science.

Beyond discovering new species…and toward solving the big puzzle

The most important parts of this work will involve more than just identifying species. In fact, the more time I spent with these researchers in the lab, (including one evening spent with them as they worked past midnight), the more I got the sense that, while they seemed excited about seeing new species, they seemed equally excited to witness relationships between animals.

When I walked into the lab one day, for example, several people urged me to go over and look through a microscope at a creature known as a pompom crab — a tiny yellow crustacean holding purple anemones in its modified front claws. Tweedt was extremely jazzed when she found something referred to as a “skeleton shrimp,” which looked to me like the marine equivalent of a stick insect, blending in on something called a hydroid. She pulled me aside another time, around one in the morning, to show me “the frosting on the cake” of the day, which turned out to be some bright red sea snails and the bright red octocorals they seemed to live on

As she put it in a later conversation, these relationships are, in many ways, the key takeaway from this ARMS project, and what distinguishes it from efforts to bring up a few individual samples at a time. Studying them, or even just looking at the fuller picture ARMS provide, is what will let researchers tackle some of the outstanding questions about these ecosystems. Bähr, for example, is already working with the data from ARMS retrieved in Guam, trying to analyze how much overlap (or lack thereof) there is between species at different depths in the deep reefs.

Really, though, this is all just the beginning. In one of our conversations, Rocha compared the work they are doing now to ecology work done in the mid-20th century to understand how species’ vertical distribution changes as you go up a mountain. This drove home for me how far behind researchers working on the mesophotic deep reefs are compared to their colleagues working on, say, shallower coral reefs. I asked him what kept him working on such a difficult puzzle.

“It’s the reward at the end of it,” he said, “If it’s a hard puzzle, at the end of it, the reward is always bigger.” 

“But…in our lifetimes, will we assemble the deep reef puzzle?” I asked.

“No, we will not assemble the puzzle, no,” Rocha said, “but we’ll generate some good pieces for the next generation to assemble.”