Earth is impressively enigmatic, with many undiscovered territories and terrains still awaiting discovery. Although geologists have scanned nearly every corner of the Earth, the possibility of hidden continents remains. In 2017, a team of geologists made a marvelous discovery in the Southern Continent, dubbing it “the eighth continent of the world.” Interestingly, this new continent, called Zealandia, was not secluded but quite conspicuous. A detailed study was published in the journal Tectonics.

Representative Image Source: Pexels | Photo by Monstera Production
Representative Image Source: Pexels | Photo by Monstera Production

Although the researchers discovered this new continent in 2017, the hunt began almost 400 years ago. In 1642, Dutch captain Abel Tasman, serving the East India Company, was ordered to explore a Southern Continent. On August 14, 1642, Tasman departed from Batavia with two ships sailing west to Mauritius in the Indian Ocean, according to Princeton University Library.

Image Source: A detailed view of the logbook of navigator Abel Tasman (Dutch East India Company) from 1642 and his journey to explore the unknown continent of Australia.  (Photo by Dean Mouhtaropoulos/Getty Images)
Image Source: A detailed view of the logbook of navigator Abel Tasman (Dutch East India Company) from 1642 and his journey to explore the unknown continent of Australia. (Photo by Dean Mouhtaropoulos/Getty Images)

On his voyage to the continent, he encountered the local Māori Indians. However, his meeting turned out to be tense, as per BBC. One day, many of these people paddled out on a canoe and rammed a small boat that was passing messages between the Dutch ships. Four Europeans died. This was the end of Tasman’s mission.



Tasman named the location “Moordenaers (Murderers) Bay,” and sailed home, never to return to this land, although he did believe that he had discovered a great new continent.



It was nearly 375 years after Tasman’s voyage that geologists stumbled upon this mainland. They announced the discovery by naming it “Zealandia,” based on the suggestion of American geophysicist Bruce Luyendyk who described this region in 1995. Zealandia is translated to “Te Riu-a-Māui” in the Māori language.


via GIPHY


In a paper, researchers from GNS Science of New Zealand documented that they had to dredge rock samples from the Fairway Ridge to the Coral Sea to analyze the rock geochemically and understand the underwater makeup of Zealandia. Led by Nick Mortimer, they scanned the northern two-thirds of the submerged area, where they unearthed pebbly and cobbley sandstone, fine-grain sandstone, mudstone, bioclastic limestone, and basaltic lava from a variety of periods as concluded by their radiocarbon dating.



The rocks and stones were found to be roughly 95 million years old, from the Late Cretaceous period. The granite and volcanic pebbles were estimated to be 130 million years old, the Early Cretaceous period. The basalts however were newer, probably about 40 million years old, and from the Eocene period. “It is kind of cool,” said Mortimer, per BBC. Andy Tulloch, a geologist at the New Zealand Crown Research Institute GNS Science, who was part of the research team, added, “This is an example of how something very obvious can take a while to uncover.”



Although Zealandia is a vast continent that spans an expanse stretched for 4.9 million square kilometers, around six times the size of Madagascar, most of it is submerged under the South Pacific Ocean. Only the area at the Ball’s Pyramid on Lord Howe Island rises above the water’s veil. It is the smallest, thinnest, and youngest of all known continents.



Usually, the continental crust is about 40 kilometers deep, thicker than the oceanic crust which is about 10 kilometers. The researchers proposed that since Zealandia ended up stretched too much, its crust became thinner, around 20 kilometers, and finally disappeared under the sea. With 95 percent of its territory submerged beneath the ocean’s depths, Zealandia prowls on planet Earth as a lair possessing an enigmatic charm of mysterious historical elements and ancient stories.

Editor’s note: This article was originally published on June 22, 2024. It has since been updated.

  • How D.C.’s ‘humanure’ fertilizer creates lush gardens and big profits while improving the environment
    Photo credit: CanvaWhat you flush away could help your garden grow.

    The District of Columbia Water and Sewer Authority—now known as D.C. Water—has long provided water and sewer services to Washington, D.C. But for the past decade, the utility has also had an unexpected side hustle: turning human wastewater into fertilizer with flourishing results.

    At most wastewater treatment plants, flushed water is cleaned, while the remaining solid matter is hauled away for disposal. Over time, transporting and disposing of that waste can cost millions of dollars while increasing carbon emissions from the trucks carrying it. A decade ago, however, D.C. Water decided to invest in transforming the solid waste into “humanure” rather than throwing it away.

    Growin’ grass and makin’ gas

    At the end of the wastewater treatment process, the collected human waste solids are processed into biosolid fertilizer using technology developed by Norwegian company Cambi. The process doesn’t just produce high-quality fertilizer—it also generates biogas that can be put to good use.

    “So you get up to 40% more biogas,” Cambi CEO Eirik Fadnes said. “That biogas can be used to generate electricity to be used elsewhere in the wastewater-treatment plant or put on the grid and sold.”

    D.C. Water sells the biosolid fertilizer under the brand name Bloom, and it’s already proving to be a success. Bloom has been used throughout the Washington, D.C., area by customers including Catholic University, Mount Olivet Cemetery, and the Franciscan Monastery. It’s also used on numerous lawns, school grounds, community gardens, and golf courses.

    Success by the numbers

    The numbers underscore D.C. Water’s success. To date, nearly 400,000 tons of Bloom have been sold across Washington, D.C., Maryland, Pennsylvania, and Virginia, generating $13.6 million in revenue. D.C. Water originally estimated it would take 20 years for Bloom to pay off its investment. But thanks to strong demand from institutions, landscapers, and local garden centers, the utility is now on pace to recoup that investment in just 12 years.

    Bloom is also helping D.C. Water meet its environmental goals. By turning waste into a useful product instead of hauling it away for disposal, the utility has reduced its carbon footprint by roughly 50,000 metric tons of CO₂ emissions each year—the equivalent of taking more than 11,700 gas-powered cars off the road annually. The process also produces biogas, which can be converted into electricity to help offset the energy costs of wastewater treatment.

    Human waste works wonders

    None of this would matter if human biosolids weren’t effective at improving soil. “Humanure,” a term coined by Joseph Jenkins, refers to compost made from properly treated human waste. Because human feces can contain disease-causing pathogens, it must be handled carefully. After all, we call it “waste” for a reason.

    When human waste is composted correctly, naturally occurring microbes break down the organic material while generating enough heat to destroy harmful pathogens. Over time, the result is a nutrient-rich compost that can improve soil health. Some farmers even build specialized outdoor composting toilets to create humanure for use on their land.

    Should D.C. Water continue on this path of simultaneous profitability and environmental improvement, it’s likely other wastewater treatment plants will follow its lead.

  • A Spanish park has been free of wildfires for over a decade thanks to 18 donkeys
    Photo credit: CanvaDonkeys and other livestock could help prevent mass wildfires.

    According to NASA, wildfires have doubled worldwide due to climate change. Throughout the globe, governments and environmentalists have been trying to find ways to curb the fires. One particular national park in Spain has found a solution that has been keeping them fire-free for over a decade: donkeys.

    Since 2014, the Firefighting Donkey Battalion unit consisting of 18 donkeys has been preventing wildfires in Doñana National Park in Doñana, Spain. The mission these donkeys do is simple: eat the dry brush that usually sparks and fuels wildfires. The donkeys spend up to seven hours a day using their voracious appetites to graze and clear a 130 by 50 feet area of dried grass, scrub, and other vegetation.

    Why donkeys?

    While humans can do this type of clearing out of dry brush, using donkeys for this work is arguably more effective. While it is a slower process, it is consistent and thorough. Donkeys are able to quietly patrol in areas that are inaccessible to vehicles. In exchange for the feasting, the donkeys get about eight gallons of water and rest. No money or fuel needed.

    The donkeys’ bodies are also pretty much built for this kind of environmental work, too. Their stomachs are built to eat the same rough and dry grass repeatedly without issues. These daily grazings slowly but surely remove potential origin sources for fires. As a bonus, the donkeys are naturally disposing of the dried vegetation whereas humans would have to find a different way to dispose of it.

    Having donkeys or other livestock graze in such areas was once more common in agriculture prior to modern farming. Some argue that the machinization of farming and urbanization have reduced the number of grazing animals. This in turn allows more vegetation growth that become dry spots for more wildfires to occur.

    The method expands

    This method has been so successful that other areas of Spain have adopted it. In 2020, Tivissa launched the Burros Bomberos project with three donkeys to so much success they’ve expanded. They now have 40 donkeys grazing and clearing nearly 400 hectares of land.

    The Andrea Association in Allariz uses a team of donkeys to clear and maintain nearly 1,000 hectares of a biosphere reserve. Using GPS to monitor the donkeys’ activity, the group of grazers travel 19 kilometers per day to feed. Similar initiatives have since started in Basque Country, Catalonia, and Galicia, too.

    Other ways to combat wildfires

    In the United States, California has been using goats in a similar function. The group Fire Grazers Inc. has been contacted throughout California to bring hundreds of goats to eat dried vegetation. Much like donkeys, goats are built to eat rough and dry brush. This includes certain plants such as star thistle that are painful for human hands to grab.

    It’s important to note that donkeys or other animals that eat dry scrub are the primary solution to wildfires. The same folks behind these initiatives also advocate proper forest planning and land management. This includes reducing the amount of easily flammable species of plants and trees such as pine. It takes thought, care, work, and maybe a bunch of donkeys to make a difference.

  • Beyond birds and mice, free‑ranging cats eat a surprising number of insects
    Photo credit: SKashkin/iStock / Getty Images PlusDoes that look tasty?

    It’s pretty commonly known, and not very startling, that free-ranging cats eat birds and small rodents. But the degree to which they eat insects might surprise you.

    We are biologists who for many years have been trying to figure out what feral or outdoor-roaming pet cats eat outside.

    When domesticated cats – Felis catus – live freely in the wild or are allowed to hunt outside the homes where their owners live, they are an invasive species, which live in every ecosystem of the world except the continent of Antarctica. We wanted to know all of the species they eat – and to what degree free-ranging cats are eating endangered or threatened species.

    Examining reams of research

    Over the past two decades, we have evaluated hundreds of scientific findings, including searching through Google Scholar and Web of Science using the keywords “cat predation,” “feral cat,” “cat diet” and “Felis catus.” For each item we found, whether peer-reviewed or not, we evaluated whether it contained conclusive evidence of cat diet or predation. We also reviewed each one’s reference section for additional unique articles or databases pertaining to cat diet and predation, and included those in our search.

    Overall, we identified 533 unique publications – books, journal articles, theses and agency reports – that reported specific animal species consumed by cats. Cats’ plant-eating habits are occasionally, but haphazardly, noted in studies, so we did not include them in our analysis.

    Our initial work focused on an overall assessment of what free-ranging cats eat around the world. Published in 2023, this paper analyzed the 533 studies on cat diet or predation events published over more than a century and found that cats ate nearly 2,100 different species of animals, including invertebrates.

    Of those 2,100, the International Union for Conservation of Nature’s Red List of Threatened Species listed 347 as “near threatened,” “vulnerable,” “endangered,” “critically endangered” or “extinct” in 2023. Some of the species went extinct during the many decades covered by the data.

    Most of the species cats eat are not in danger

    Insects and the like

    Most of the species cats ate were vertebrates – mostly birds, followed by mammals and reptiles. But the data also indicated that at least 7% of the species cats eat are insects and other invertebrates, particularly beetles, and less frequently crustaceans, arachnids, centipedes, snails and slugs, and millipedes.

    Many of the cat studies we reviewed did not report on how many individuals of a given species cats ate, so it was unclear what the total amount of insects was or how many calories cats are deriving from insects.

    Invertebrates make up more than 70% of all terrestrial animal species and are important pollinators, predators and herbivores in virtually every nonmarine ecosystem. Many invertebrates are in decline globally due to urbanization, habitat destruction, increases in both light and pesticide pollution, and climate change. So we dug deeper into the data to understand what invertebrates cats are eating.

    While a little more than one-third of all the studies we analyzed included invertebrates as part of cats’ diet, most of those failed to identify specific species of invertebrates. But we were able to find identifications of 148 invertebrate species.

    Of those, two are considered endangered by the International Union for Conservation of Nature: the Aldabran grasshopper (Pternoscirtus aldabrae) in Seychelles and the Tasmanian giant freshwater crayfish (Astacopsis gouldi), which can grow up to 13 pounds (6 kilograms). Two others are considered vulnerable: wētāpunga (Deinacrida heteracantha), an insect native to New Zealand that can be about the size of a mouse, and the common yabby (Cherax destructor), a freshwater crayfish native to southeastern Australia. One other, the Canary Islands horned beetle (Arhopalus pinetorum), is listed as “near threatened.”

    A cat licks its lips while crouching over a dead mouse.
    Not surprising: Cat eats mouse. Julian Stratenschulte/picture alliance via Getty Images

    Effects on populations

    We have not found formal research evaluating how cats’ eating habits affect invertebrate populations. And for many species, they are likely not as significant a factor as wide-scale pesticide use.

    But it’s possible that cats could be significant contributors to the deaths of rare species or in specific locations.

    Cats require a large amount of protein, as much as one-third of their daily diet, and invertebrates are good sources of protein.

    In many places, invertebrates provide an easy source of food. Whether in an urban backyard or on a remote island, cats are unlikely to turn a blind eye to available prey. And some cats may find it entertaining to chase, catch and eat insects even if they don’t need their nutrition.

    A challenge of researching this question is that many invertebrates are relatively small, which makes direct observation in the field harder and can require more analytical approaches in the lab. And they have soft bodies, without distinguishing characteristics that could be easily recognized in scat or stomach contents.

    However, molecular technologies can identify species using trace amounts of DNA left in the environment by animals. Promising new studies are beginning to identify what cats eat by analyzing the DNA found in their stomachs and scat. That research may help explore in even more detail what cats are eating in the outdoors, and how it’s affecting various species and the environment as a whole.

    This article originally appeared on The Conversation. You can read it here.

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