Tuesday, November 30News That Matters

Tag: your-feed-animals

Why Was This Ancient Mammoth Tusk Discovered at the Bottom of the Ocean?

Technology
Mammoth tusks that are over 100,000 years old are “extremely rare,” Mr. Mol added, and studying one could give scientists new insights about the Lower Paleolithic, a poorly understood era of Earth’s history.Scientists know that around 200,000 years ago Earth was experiencing a glacial period and our ancestors were migrating out of Africa. But they don’t know exactly how the planet’s changing climate affected mammoths and other large animals during this time. What is also unclear is how arrival to North America altered the genetic diversity of mammoths.“We don’t really know much of anything about what was happening during that time period,” Dr. Fisher said. “We don’t have access to a lot of specimens from this time period and that’s due in large part to the fact that getting access to sedim...
Bees Make This “Screaming” Sound When Attacked By Hornets

Bees Make This “Screaming” Sound When Attacked By Hornets

Technology
Bees do not scream with their mouths, but with their bodies. When giant hornets draw near and threaten their colony, Asian honeybees cock their abdomens into the air and run while vibrating their wings. The noise can sound eerily like a human scream.In a paper published Wednesday in the journal Royal Society Open Science, researchers describe the Asian honeybee’s unique acoustic signal, which is called an antipredator pipe. The researchers colloquially refer to it as a “bee scream.”“It’s like a shriek,” said Hongmei Li-Byarlay, an entomologist at Central State University in Ohio, who was not involved with the new research. Dr. Li-Byarlay added that her colleagues who have observed the sounds before compared the noise to “crying.”The bees make this sound as their nests are threatened by the...
This Fish Loses 20 Teeth Each Day, Then Grows Them All Back

This Fish Loses 20 Teeth Each Day, Then Grows Them All Back

Technology
If there is one place you don’t want to stick your finger, it’s the mouth of a Pacific lingcod. These fearsome fish, which can grow up to five feet in length and weigh 80 pounds, have around 500 needlelike teeth sticking out of jaws that are strong enough to crush crustaceans.Having so many sharp chompers allows these ambush predators to subdue everything from slippery squid to heavily armored crabs. How lingcod maintain the sharpness of their terrifying teeth has long been a mystery. But a study, published in October in the Proceedings of the Royal Society B, claims that Pacific lingcod keep their teeth sharp and shiny by replacing about three percent of them every day. For a lingcod, that’s a whopping 20 teeth replaced daily. If you replaced your teeth at the same rate, you might lose an...

As Earth Warms, Human History Is Melting Away

Technology
To hear more audio stories from publications like The New York Times, download Audm for iPhone or Android.For the past few centuries, the Yup’ik peoples of Alaska have told gruesome tales of a massacre that occurred during the Bow and Arrow War Days, a series of long and often brutal battles across the Bering Sea coast and the Yukon. According to one account, the carnage started when one village sent a war party to raid another. But the residents had been tipped off and set an ambush, wiping out the marauders. The victors then attacked the undefended town, torching it and slaughtering its inhabitants. No one was spared.For the last 12 years, Rick Knecht has led an excavation at a site called Nunalleq, about 400 miles west of Anchorage. “When we began, the hope was to learn something about ...
Shark Attacks May Be Explained by Case of ‘Mistaken Identity’

Shark Attacks May Be Explained by Case of ‘Mistaken Identity’

Technology
Baby white sharks learn to hunt on the fly. Though months-old pups feast on fish and other small fry, older juveniles are finally big enough to tackle seals and other meatier meals.It might seem easy to spot a blubbery seal in the waves. But young white sharks have less than stellar eyesight and are also likely colorblind, rendering the ocean in shades of gray. So you can hardly blame a young white shark for seeing an appetizingly shadowy oval above and chomping.For decades, scientists have floated this theory of “mistaken identity” as an explanation behind unprovoked shark bites on humans, which are rare. A paper published Wednesday in the Journal of the Royal Society Interface puts this theory to the test. Based on their simulations of how a juvenile white shark sees the world, they foun...
How to Map a Fly Brain in 20 Million Easy Steps

How to Map a Fly Brain in 20 Million Easy Steps

Technology
The brain of a fruit fly is the size of a poppy seed and about as easy to overlook.“Most people, I think, don’t even think of the fly as having a brain,” said Vivek Jayaraman, a neuroscientist at the Janelia Research Campus of the Howard Hughes Medical Institute in Virginia. “But, of course, flies lead quite rich lives.”Flies are capable of sophisticated behaviors, including navigating diverse landscapes, tussling with rivals and serenading potential mates. And their speck-size brains are tremendously complex, containing some 100,000 neurons and tens of millions of connections, or synapses, between them.Since 2014, a team of scientists at Janelia, in collaboration with researchers at Google, have been mapping these neurons and synapses in an effort to create a comprehensive wiring diagram,...

Behold, the Worm Blob and Its Computerized Twin

Technology, World
In the wild, a worm blob looks like any other mud ball lolling around the bottom of a pond. But if you poke an unassuming worm blob, it will respond in a way a mud ball never would, wriggling out into a noodly shape that a Pastafarian might mistake for something divine.This is how Saad Bhamla discovered his first worm blob, in a pond in California. “As you poke it with a stick, it comes alive,” said Dr. Bhamla, a bioengineer at the Georgia Institute of Technology’s school of chemical and biomolecular engineering. Dr. Bhamla’s encounter with the worm blob haunted him for years (in a good way, he says) until he started his own lab and needed a first project.California blackworms, soft and slender ropes as surreally red as grocery store meat, often live in seasonal pools. When times are good,...
Tuskless Elephants Escape Poachers, but May Evolve New Problems

Tuskless Elephants Escape Poachers, but May Evolve New Problems

Technology
The team sequenced the genomes of 11 tuskless females and seven with tusks, looking for differences between the groups. They also searched for places in the genome showing the signature of recent natural selection without the random DNA reshuffling that happens over time. They found two genes that seemed to be at play.Both genes help to build teeth. The one that best explains the patterns scientists saw in nature is called AMELX, and is on the X chromosome, as the team expected. That gene is also involved in a rare human syndrome that can cause tiny or malformed teeth. AMELX is adjacent to other crucial genes whose absence from the X chromosome can kill males. In the elephant genome, “We don’t know what the exact changes are causing this loss of tusks, in either one of those genes,” Dr. Ca...
How Hungry Sea Otters Affect the Sex Lives of Sea Grass

How Hungry Sea Otters Affect the Sex Lives of Sea Grass

Technology
Jane Watson studied sea otters for decades, but it was in the 1990s that the ecologist in British Columbia observed they had a destructive habit. While conservationists were working diligently to restore damaged sea grass meadows elsewhere in the world’s oceans, it seemed ironic that in northern Vancouver Island’s sea grass habitat, which is much healthier than others in the world, the furry floaters would swoop in and dig for clams, dislodging the aquatic vegetation.As she and others examined the sandy bottoms pock marked with clam-digging pits, Dr. Watson anecdotally noted that in places with long-established otter populations, the grass, known also as eelgrass, seemed to flower more frequently.She wondered: Were these disruptive otters influencing plant reproduction? She sat on the idea...
These Worms Left the Ocean Floor and Never Looked Back

These Worms Left the Ocean Floor and Never Looked Back

Technology
The average scale worm trudges along the seafloor like a tiny armored tank. The worm’s overlapping scales shield its backside from predators, while bristled appendages help it scuttle through the mud. This is a good life for a worm, said Katrine Worsaae, a marine zoologist at the University of Copenhagen.“Worms love mud,” Dr. Worsaae said.But some scale worm species have evolved to leave the mud behind and swim up into the water column. Some even live their whole lives suspended in water, never needing to touch the ground. To accomplish this grand liftoff, the worms evolved less muscle mass and elongated appendages that stroke through the water like oars, according to a paper published on Wednesday in the journal Royal Society Open Science.The paper is a collaboration between researchers a...