There’s no going back. New Zealand has been irreversibly changed since COVID-19 first arrived here in February. How will this end?
While normal earthquakes release energy suddenly and catastrophically, the slow-motion variety can last from days to months, can’t be felt by humans, and cause no damage. Slow-slip earthquakes were discovered around 20 years ago, and scientists are still trying to figure out what causes them. New Zealand’s Hikurangi Subduction Zone, off the east coast of the North Island, has become a global hotspot for the study of slow-slip quakes, because they happen at shallower depths than they do elsewhere, and so are easier to measure. The Hikurangi Subduction Zone is where the Pacific Plate is being shoved underneath the North Island, which lies on the edge of the Australian Plate. Off the coast of Wellington and the Wairarapa, the seabed is covered in sediment washed off the Southern Alps. That gives the Pacific Plate a nice, smooth surface, and as it’s pushed underneath the Australian Plate, the two plates tend to lock tightly together. (Every 500 years or so, this breaks in a giant megathrust earthquake of magnitude 8 or 9.) North of Hawke’s Bay, it’s a different story. There’s less sediment, so ancient undersea volcanoes called seamounts stick up out of the Pacific Plate, giving it a bumpy surface. That causes all kinds of strange behaviour as it’s sucked beneath the Australian Plate. GNS Science geophysicist Susan Ellis and her colleagues used a sophisticated computer model to simulate what happens when a seamount is pulled into the subduction zone. “The ground ahead becomes brittle and prone to earthquakes because the water is squeezed out,” says Ellis. As the seamount inches forward, it drags the seabed with it, stretching apart the rocks behind it and allowing fluids to fill tiny gaps in the rock. That weakens the rocks and makes slow-slip earthquakes possible. Researchers are trying to figure out what this means for New Zealand. How much of the stress built up along the fault will be released in slow-slip events? What will happen when the southern part of the Hikurangi Thrust eventually ruptures in “the big one”—something that hasn’t happened in recorded history?
A particularly virulent strain of avian influenza called H5N1 has spread to more than 60 countries since it was identified in 1996. The virus’s fatality rate in humans ranges from 50 to 60 per cent, but it hasn’t figured out how to leap between human and human: it can only make the jump between birds and people. An international consortium of scientists studied how the virus spreads, and found that its travel is associated with China’s live poultry trade. The same was true of two other strains of bird flu. “While the H5N1, H7N9 and H5N6 avian influenza viruses have not yet learned to transmit human-to-human,” says New Zealand virologist Robert Webster, “they do have pandemic potential.”
The ship rat genome has been sequenced for the first time—in the hope that this will reveal Rattus rattus’s weaknesses.
Where do cats go—and how lethal are they? Researchers put trackers on 925 pet cats in Australia, New Zealand, the United Kingdom and the United States, through four citizen science projects, in order to figure out how large the cats’ home range was, and how often they killed. They found that the average domestic tabby had a similar ecological impact as a wild predator, but over a small range; the cats killed on average 3.5 animals per month within 100 metres of their home. Only three cats in the study roamed more widely than a square kilometre—one New Zealand cat roamed over farms, while a British cat walked almost two kilometres between villages. Older cats, male cats, and urban cats moved less. The researchers recommended pet owners find ways to entertain their cats indoors in order to reduce their environmental impact. Meanwhile, a small study on the role of pets in the health of older adults had an unanticipated finding; Australian researchers interviewing 35 people aged 60 to 83 were surprised to learn that pets had protected some from suicide. Twelve of the study’s participants spoke about how their pets gave them a reason to live. Caring for an animal gave them a sense of purpose, its physical presence warded off loneliness, and, most importantly, they felt “known” by their pets.
You’ve hurt yourself in the mountains, and you’ll never make it out on your own. What happens next?
Out in the deep ocean, where it’s darker than a moonless night all day long, packs of two-metre-long Humboldt squid go hunting. They spend their short lives on fast-forward—always on the move, always hungry, even turning on their own kind if an individual shows a moment’s weakness. They’re also highly social, and a new study suggests they use a complex visual language to communicate in the deep. Studying the behaviour of deep-sea creatures like the Humboldt squid isn’t easy, says author Benjamin Burford from the Monterey Bay Aquarium Research Institute. “They’re born in the open ocean, they die in the open ocean—they never touch a hard surface in their life. They don’t know what a wall is. So when you bring them into captivity, they will ram themselves to death in a tank. It’s way better to meet them where they live.” To do that, Burford and co-author Bruce Robison sent high-definition video cameras 800 metres deep in the Pacific Ocean’s California Current, and analysed the flickering and flashing displays Humboldt squid were using. They identified a repertoire of 28 pigmentation patterns—such as “mottled”, “dark fins”, or “pale circles around the eyes”. The squids used particular combinations of these signals while feeding: they’d go half-dark, half-light when approaching prey, add a dark spot between the eyes, then flash pale all over when pouncing. When it’s so dark, how can they make out the signals? Humboldt squid have bioluminescent photophores scattered over their body. Unusually, they’re not in the skin, but buried beneath in their muscles. Burford mapped the location of these cells and found the areas with the highest densities corresponded to the parts of the body used in some of the most important signals. That suggests the squid use their bioluminescent bodies to make their changing skin patterns easier to see. “They’re basically concealing and revealing different parts of a glowing body,” says Burford. So, what are they saying? “When Humboldt squid feed, it looks like a feeding frenzy. But if you pay close attention, they’re not bumping into each other, they’re not attacking each other, they’re rarely even in competition for the same prey item. We think the pigmentation patterns they’re producing are helping them organise this chaos, so it doesn’t end in catastrophe—in a misunderstanding that leads to fighting and injury or death.” Burford likens it to using indicators, brake lights and horns when stuck in traffic. The squid are saying things like, “I’m going for that fish over there, and stay out of my way, because I’m dominant around here.” But it’s also more complicated than that. It looks as though the squids combine signals to make new meanings—a kind of syntax. “Is it language? It’s definitely a way of communicating, which is what we use language for.” It should be possible to create a squid hologram, project different visual behaviours on it, and test how wild Humboldts react to it, says Burford. “Maybe some day we’ll learn how to speak squid.”
Shaun Hendy stays up late predicting the future.
Palaeontologists have discovered our earliest ancestor—a tiny, bug-like creature that burrowed in the mud half a billion years ago. It is the first known bilatarian—an animal that’s largely symmetrical and has a front and a back, with a mouth at one end and an anus at the other. This body type turned out to be a successful innovation. It’s the shape sported by most animals today. “We now have evidence of the origin of groups of animals which went on to conquer the Earth,” says James Gehling from the Australian Museum, co-author of a paper describing the new species. It was named Ikaria wariootia. Until now, palaeontologists traced our ancestry to the explosion of marine lifeforms in the Cambrian period, which began 541 million years ago. It was thought that fossils from the earlier Ediacaran period represented some of evolution’s failed experiments—dead ends on the family tree. But this discovery, made in South Australia’s Flinders Ranges, shows that our lineage dates all the way back to the Ediacaran. The Ediacaran was “a very weird world”, says Gehling. “Little bugs like the Ikaria were ploughing through thin layers of sand, eating microbial mats. The world was really one of slime. We have nothing equivalent to it today. You’ve got to think as though you’re on a different planet.” The name acknowledges the Adnyamathanha, the indigenous custodians of the land on which the fossils were found. Ikaria is a nod to Ikara, the Adnyamathanha word for meeting place, while the species name comes from nearby Warioota Creek. There’s still so much we don’t know about these ancient animals and their strange home, says Gehling. “But whatever they were, life expands after that point and changes the planet—and that interaction between life and environment is something that indigenous people have always thought about. What we’re doing here is acknowledging that we scientists aren’t the first people that needed to understand origins.”
Storms upend lake ecosystems, causing confusion in their microscopic communities, according to a new study involving NIWA scientists. The study looked at the existing research on phytoplankton, the base of the food web and a determinant of water quality, but found little information on how storms affect it. “If extreme weather events significantly change carbon, nutrient, or energy cycling in lakes, we better figure it out quickly,” says Jason Stockwell, an aquatic ecologist at the University of Vermont who led the new research, “because lakes can flip, like a lightbulb, from one healthy state to an unhealthy one—and it can be hard or impossible to flip them back again.”
Sea lions are coming home to the coasts of southern New Zealand, returning to their former territory after more than 300 years in exile. The big question is: Can we make room for them?
Virologists have been issuing warnings about pandemics for years; human history is blighted with them. Yet we’re more careful about the microbes we bring back from space than we are about preventing spillovers of viruses from animals to humans. Viruses are terrifying. Think of them as tiny machines with no “off” switch. They simply continue indefinitely with what they’re programmed to do—replicate themselves by taking over your cells—until they’re destroyed. We missed an opportunity to prepare for this. In 2012, when the government was formulating our 11 National Science Challenges—research collaborations between institutions—it asked the public for its opinion on which large-scale problems should be confronted. Eight scientists were filmed presenting eight potential topics. The video that won the most public votes was fronted by microbiologist Siouxsie Wiles, who spoke about the challenges posed by infectious diseases. But the panel deciding on the final form of our National Science Challenges, led by Sir Peter Gluckman, rejected the topic. There wasn’t enough research capacity in New Zealand for infectious diseases, the panel wrote, and passed up an opportunity to constructively add to that understanding. New Zealand isn’t alone in sidelining infectious diseases, says Shaun Hendy, director of national research centre Te Pūnaha Matatini. “The whole world, apart from a few countries, has been very complacent about infectious disease.” Yet the past month has seen New Zealand’s researchers leap into collaboration both nationally and internationally. This style of collaboration has emerged without an overarching organisation, says Hendy. “One of the reasons we’ve coped so well, despite that lack of preparation, is that there are good relationships across the science community, good networks of people that will down tools and work together even when the system doesn’t necessarily facilitate it.” This is also taking place globally. Competing drug companies are working together on the development of a vaccine, while academic journals have opened free access to coronavirus research. There has been an exponential curve in the number of scientific papers published on COVID-19: the number of them doubles every 14 days. One thing we do have in New Zealand is a government that listens to science and is prepared to hear a diverse range of voices. In some other nations, says Hendy, “You only get to be in the room as a scientist if you’re telling [politicians] what they want to hear. And that’s not the case here. We do have politicians who can take critique.” This foreshadows the next big challenge on our horizon—climate change, which will require global collaboration at an even larger scale. And in the same way that a pandemic was difficult to imagine in January, this is a challenge that’s difficult to get our heads around—a challenge for which the solutions seem impossible. “Climate change is moving at virus-like speed but we don’t think that way, we still think it’s years ahead or decades ahead,” business commentator Rod Oram told New Zealand Geographic journalist Dave Hansford. “There’s a feeling among lots of people—‘Oh, something will turn up’, or ‘It won’t be quite as bad as we think it will be’, or ‘We’ll be okay in New Zealand’. “People are still approaching climate change in the same way, ‘Oh, we’ll kind of hang in here until there’s some magical solution,’ but there isn’t one. There isn’t a vaccine for climate change. This is inexorable and largely irreversible.”
The return of Halley’s Comet in 1910 prompted a deluge of fake news.
Freelance jockeys, keen spectators, farming families with station hacks and horse trainers with thoroughbreds descend on the Wairarapa every autumn to take part in one of New Zealand’s longest-running events.
Brett Phibbs takes on the essential service of documenting an unprecedented month in New Zealand history.
The once abundant Hauraki Gulf is on the brink of collapse, and while science is clear on how to repair it, many are putting rights before responsibilities. Here’s what needs to happen.
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