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The brand-new seabird of Whenua Hou

Whenua Hou, a tiny island off the coast of Stewart Island, is most famous for its population of kākāpō, but it also has a one-kilometre strip of beach where diving petrels breed. These have just been identified as a unique species, the Whenua Hou diving petrel, Pelecanoides whenuahouensis. While there are 15 million diving petrels around the world, Johannes Fischer of Victoria University in Wellington concluded that this tiny colony was a different species for a variety of reasons: their feather colours, DNA, deeper bills, longer heads, and different species of feather lice. They’re also the only diving petrel to breed entirely within a sand-dune environment. The species numbers about 150 birds, making it critically endangered. Its entire population nests in this fragile, changeable place.
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The first colour X-rays

What if it was possible to take pictures of the inside of the human body—colour pictures, where bone and muscle were easily distinguishable from pathologies such as cancer tissue or kidney stones? Earlier this year, New Zealand scientists performed the first-ever colour x-ray of a human body, using particle-tracking technology that had originally been developed for CERN’s Large Hadron Collider, the world’s largest particle accelerator. When x-rays pass through the human body, they are absorbed differently by different internal organs. They travel straight through soft tissue, such as muscle and fat, but are impeded by denser materials, such as bone. Then the x-rays hit a metal film, which creates an image based on the intensity of the radiation that emerges. Areas where the x-rays were blocked are white, and areas they were able to pass through are black. By contrast, a new scanner the New Zealand scientists developed records each change in wavelength as the particles hit different parts of the body—bone, muscle, liquid, fat, cartilage, tumour. When the x-rays emerge, software assigns a colour to each of those energy levels. The scanner was developed in part by the Universities of Otago and Canterbury, alongside New Zealand company Mars Bioimaging, using a detector that had originally been designed to spot subatomic particles. While x-ray photons have always had this energy information contained within them, the Mars Bioimaging scanner is the first technology capable of measuring it. Because traditional x-ray imaging only records whether the radiation passed through the body, it doesn’t reveal much about the soft tissue or muscle surrounding the bones. Small versions of the colour scanner are now being used to study cancer, bones and joints, and Mars Bioimaging hopes to produce body-part scanners specialised for areas such as knees and ankles.
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How rats shape coral reefs

When rats consume the eggs and chicks of coastal-nesting seabirds, this affects fish and coral reefs offshore, according to a letter published in Nature in July. If birds are killed, this prevents their droppings from reaching marine ecosystems, meaning that underwater species miss out on the boost of nutrients provided by this natural fertiliser. The Chagos Archipelago in the Indian Ocean, south of the Maldives, is an ideal place to study the effects of rat populations—18 of its 55 islands are rat-free, while rats have been in residence on the others for centuries. An international team of researchers found seabird densities were 760 times higher on rat-free islands, which also had 251 times more nitrogen deposited from seabird droppings. Tracking nitrogen isotopes on the coral reefs around the islands, the scientists found nitrogen from birds present in seaweed, sponges and turf algae. They observed that herbivorous damselfish grew faster, and fish communities in general had 48 per cent more biomass, compared to the rat-covered islands next door. This suggests rat eradications could alleviate pressure from climate-stressed coral reefs.
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Are humans allergic to the moon?

Astronauts from the Apollo missions reported that breathing in the moon dust on their suits resulted in sneezing, watering eyes and sore throats. After analysing dust particles in the lab, United States researchers suggest they are toxic to human lung cells and mouse brain cells.
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The ferocious plant that went rogue

First introduced in the 1870s for hedges, African boxthorn soon went rogue. It thrives in coastal areas, as it can handle dry, salty, sandy, windy, hot and cold conditions. Up to six metres tall, it crowds out other plants with its 13-millimetre spines. Thorns can get stuck in cattle hooves, pierce gumboots, and puncture tyres. ‘Lycium’ means ‘thorny shrub’ and ‘ferrocissimum’ means ‘ferocious’. Seabirds can get tangled up in clumps of boxthorn as they land or take off, and quickly die of starvation and exposure. The Department of Conservation is battling boxthorn on the predator-free island Motunau, a place teeming with seabird burrows. In Taranaki, boxthorn was once in demand. Seeds and seedlings were sold by nurseries and locals, and sheep-proof hedges were planted. Boxthorn honey and boxthorn jam were popular, and boxthorn wood was good firewood. Now, hedges are more likely to be bulldozed and burned.
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How long can penguins hold their breath?

A new record has been set for the longest dive by an emperor penguin. In a study led by NIWA marine ecologist Kim Goetz during the penguin breeding season, 20 birds that hadn’t paired up were tagged and tracked in the eastern Ross Sea. These birds dived 96,000 times over six months, and while most dives were around the five-minute mark, one lasted a record-breaking 32.2 minutes. (Previously, the longest dive was 27.6 minutes.) Penguins dive in order to catch fish, krill and squid, and the study found they dived deeper and longer during the day and at twilight, consistent with using eyesight to hunt.
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Galaxy smash

At least 14 gas-rich galaxies have been discovered on the verge of merging, according to a study published in Nature—and the authors say this is the most massive structure in the Universe. Called SPT2349-56, this cluster lies about 12.4 billion light-years away. Within each galaxy forming it, stars are growing 50 to 1000 times faster than they are in the Milky Way. But the cluster takes up a space only three times bigger than the Milky Way—a density which means all 14 galaxies will be forced to quickly merge into one ‘mega-galaxy’, says study author Scott Chapman. Further data from the Atacama Large Millimeter Array in northern Chile shows these 14 galaxies are just the beginning—there are even more galaxies close by.
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When plants avoid their neighbours

Plants are social beings. When leaves from different plants touch each other, their roots send out signals, telling the other plant to get lost. New research from the Swedish University of Agricultural Sciences, published in PLOS One in May, found that maize seedlings whose leaves were touched give off chemicals via their roots, which cause non-touched maize seedlings to grow away from them. Study co-author Velemir Ninkovic says the chemicals signal a crowded environment, so other plants choose environments with less competition and therefore more resources. Later on, seedlings exposed to these root chemicals also grow more leaves—a typical plant response to avoid being left in the shade.
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Save or restore

If an ecosystem has been severely damaged, can it recover? Almost never, according to a new study—even when active restoration takes place. Researchers from Northern Illinois University looked at 400 studies of ecosystems worldwide that had been destroyed or damaged by logging, mining, oil spills, agriculture, or nutrient pollution. Human-driven restoration didn’t speed up their recovery, or restore biodiversity any better than simply leaving areas to recover on their own. The study’s authors say their research reinforces the need to conserve intact ecosystems, because disturbed ones take such a long time to recover, and never return to their previous state.
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How the 1918 flu spread

One hundred years ago, an influenza pandemic tore across the world, infecting 500 million people, and killing between 50 and 100 million—between three and five per cent of the world’s population. But it wasn’t equally lethal everywhere it visited. In Tasmania, less than 0.1 per cent of the population succumbed, while Western Samoa saw a mortality rate of 22 per cent. Why the disparity? A study by New Zealand and Australian researchers, published in The Lancet Infectious Diseases in May, suggests that prior exposure to a non-lethal flu virus, social isolation, and ethnic immune systems are some of the factors. Māori were 10 times as likely as pākehā to die from the flu. Study co-author Nick Wilson, a professor of public health at the University of Otago, says this was likely due to higher rates of poverty and thus more crowded living conditions. Because a greater proportion of Māori lived rurally, earlier waves of the virus, which arrived before November 1918, might not have reached them to give them increased immunity. Mysteriously, Māori men and women were affected equally. (In all other populations, more men died from the flu than women.) Wilson says Samoa was also unusual in that the flu spread fastest through the highest social class. “This was because in Samoan culture, when a chief was sick, a lot of people would gather round him to transfer oral knowledge to the next generation—customs such as this would have increased spread.” He says this level of global mortality from a virus is unlikely to ever happen again. “The world is so interconnected that almost everyone gets exposed to most flu viruses within a few years, as opposed to in the sailing and steamship days when populations could go decades without seeing a particular virus.” The main cause of death during the 1918 pandemic wasn’t the flu itself, but the bacterial pneumonia that followed it. These days, it could be treated with antibiotics.
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The krill effect

A one-centimetre-long shrimp can’t create an ocean current when it swims, but en masse, these tiny creatures could be contributing to ocean mixing. A Stanford University study published in Nature watched brine shrimp, Artemia salina, as they swam in a tank. When they swim upwards, as a band just 50 centimetres deep, their wake mixes the water 1000 times more than it would mix naturally. Ocean krill are five times the length of brine shrimp, and twice a day they vertically swim hundreds of metres as a group in a band tens of metres deep—which the authors say means the krills’ downward jets could have a collective effect on ocean mixing.
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Name of the whale

The oldest ‘true’ baleen whale fossil ever found, at more than 27.5 million years old, was excavated about 30 years ago from a dairy farm at Hakataramea in South Canterbury. In April, it was finally named: Toipahautea waitaki, which translates to ‘baleen origin whale of the Waitaki region’. The University of Otago’s Māori Affairs department and Ngāi Tāhu were consulted for help with the name. Many New Zealand species’ Linnaean names carry te reo in part or in full. However, University of Waikato associate professor Hēmi Whaanga says while it’s important te reo is used, care must be taken because naming is often done without consultation with local iwi. “It’s a respect thing—we need to consider the names we plan to use might be sacred, refer to history, genealogy, places, events. Using them in another context can confuse people on the true meaning, or it may be culturally inappropriate to use that name.” Name blunders of the past include the hybrid te reo-Latin Taniwhasaurus oweni, a mosasaur named in 1874. Using te reo in Linnaean naming still desperately needs protocol, says Whaanga: “Once it’s named, you can’t change it.”
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Shining a light on Zika

An old tool that has been used for decades to determine which chemicals are in foods, the human body and pharmaceuticals could now be used to see if a mosquito is carrying the Zika virus. The microcephaly-causing virus has spread by mosquito into many new countries in recent years, including Fiji, Samoa and Tonga. A major challenge in monitoring the situation has been the lack of fast, affordable tests. Currently, genetic material is analysed for the virus using the reverse transcription polymerase chain reaction (RT-qPCR). But a study published in Science Advances has found that near-infrared spectroscopy (NIRS) predicts Zika with between 94.2 and 99.3 per cent accuracy. NIRS simply involves shining a light at the head and thorax of the mosquito to read the chemical compounds within. It’s 18 times faster and 116 times cheaper than RT-qPCR, with no need for dissections or reagents.
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Second-rate grains

Climate change will affect the nutritional composition of rice for the worse, according to a study which grew rice plants under different carbon dioxide levels. The research, published in Science Advances in May, found that simulating atmospheric carbon dioxide levels predicted at the end of the century (570 parts per million, compared with the current 410) resulted in a grain with lower levels of protein, iron and zinc, as well as lower levels of the vitamins B1, B2, B5 and B9. More than two billion people depend on rice as their primary food source.

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