By Lauren Sharkey

Melanoma is the deadliest form of skin cancer. With its incidence rates continuing to rise, researchers are looking for ways to spot it early on. A new laser device may be able to do so instantly.

“With skin cancer, there’s a saying that if you can spot it you can stop it — and that’s exactly what this probe is designed to do,” says Daniel Louie, a Ph.D. student at the University of British Columbia (UBC) in Canada.

Louie has helped design a low-cost device that can quickly detect cancerous skin cells.

Skin cancer is the most common cancer in the United States, according to the Centers for Disease Control and Prevention (CDC).

Typically split into two categories — melanoma and nonmelanoma — the condition can result in a series of complications if a person does not seek treatment.

While nonmelanoma cases may lead to disfigurement, melanoma can be deadly. Also, melanoma’s rates have been going up for the past 30 years, according to the American Cancer Society.

It is now one of the most common cancers in young adults, particularly young women.

How light waves detect cancer

Detecting the cancer early is essential for a good prognosis. One way to do so is using light waves. As these pass through objects, they scatter in a certain way. Louie used this principle to design a laser probe that could interpret these patterns within seconds.

“Because cancer cells are denser, larger, and more irregularly shaped than normal cells, they cause distinctive scattering in the light waves as they pass through,” he explains.

Researchers from UBC, BC Cancer, and the Vancouver Coastal Health Research Institute analyzed these light beam changes. They examined 69 lesions from 47 people at the Vancouver General Hospital Skin Care Centre in Canada.

This research — the results of which now appear in the Journal of Biomedical Optics — informed the probe’s design. Not only can it show the precise pattern of laser beams, but it can also very easily read them to detect the presence of cancer.

https://www.medicalnewstoday.com/articles/324690.php

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By Alison George

Human speech contains more than 2000 different sounds, from the ubiquitous “m” and “a” to the rare clicks of some southern African languages. But why are certain sounds more common than others? A ground-breaking, five-year investigation shows that diet-related changes in human bite led to new speech sounds that are now found in half the world’s languages.

More than 30 years ago, the linguist Charles Hockett noted that speech sounds called labiodentals, such as “f” and “v”, were more common in the languages of societies that ate softer foods. Now a team of researchers led by Damián Blasi at the University of Zurich, Switzerland, has pinpointed how and why this trend arose.

They found that the upper and lower incisors of ancient human adults were aligned, making it hard to produce labiodentals, which are formed by touching the lower lip to the upper teeth. Later, our jaws changed to an overbite structure, making it easier to produce such sounds.

The team showed that this change in bite correlated with the development of agriculture in the Neolithic period. Food became easier to chew at this point, which led to changes in human jaws and teeth: for instance, because it takes less pressure to chew softer, farmed foods, the jawbone doesn’t have to do as much work and so doesn’t grow to be so large.

Analyses of a language database also confirmed that there was a global change in the sound of world languages after the Neolithic era, with the use of “f” and “v” increasing dramatically in recent millennia. These sounds are still not found in the languages of many hunter-gatherer people today.

This research overturns the prevailing view that all human speech sounds were present when Homo sapiens evolved around 300,000 years ago. “The set of speech sounds we use has not necessarily remained stable since the emergence of our species, but rather the immense diversity of speech sounds that we find today is the product of a complex interplay of factors involving biological change and cultural evolution,” said team member Steven Moran, a linguist at the University of Zurich, at a briefing about this study.

This new approach to studying language evolution is a game changer, says Sean Roberts at the University of Bristol, UK. “For the first time, we can look at patterns in global data and spot new relationships between the way we speak and the way we live,” he says. “It’s an exciting time to be a linguist.”

Journal reference: Science, DOI: 10.1126/science.aav3218

https://www.newscientist.com/article/2196580-humans-couldnt-pronounce-f-and-v-sounds-before-farming-developed/

By Elizabeth Chuck and Lauren Dunn

The intrusive thoughts started weeks after Stephanie Hathaway gave birth: an overwhelming feeling that her daughter deserved a better mother; that her husband deserved a better wife; that her future was hopeless.

“They just played on repeat in my head,” Hathaway, 33, of South Glastonbury, Connecticut, said. “I was holding my baby one night, and my husband was at a meeting, and I just thought, ‘Oh, my goodness. If I put the baby down, I might hurt myself.’”

Hathaway was diagnosed with postpartum depression — the intense sadness, anxiety or despair that occurs within the first year after giving birth, according to the Centers for Disease Control and Prevention. It affects about one in nine women, although the rate may be as high as one in every five women, the CDC finds.

Hathaway’s doctor put her on antidepressants, which helped some, but it took two weeks for the medication to kick in, and even longer until her doctor found the appropriate dosage for her. As she waited for relief, Hathaway found herself struggling to bond with her newborn, Hadley, who is now 4.

“It’s heartbreaking,” Hathaway, who had never suffered from depression before and is now a mother to two girls, said. “That’s not what I expected to feel.”

Up until this point, new mothers experiencing postpartum depression have been prescribed the same antidepressants used for treating depression in the general population, such as selective serotonin reuptake inhibitors. The drugs can take weeks to take effect, and do not address the hormonal changes that women go through during and after pregnancy.

But on Tuesday, the Food and Drug Administration approved the first drug specifically developed for postpartum depression, called brexanolone, or Zulresso.

Brexanolone is novel because it has a synthetic form of the hormone allopregnanolone, a progesterone derivative, in it. The hormone increases throughout a woman’s pregnancy and then plummets after she gives birth, a possible contributor to postpartum depression.

“This can potentially transform women’s lives and that of their families,” said Dr. Steve Kanes, chief medical officer of Sage Therapeutics, the Cambridge, Mass., biopharmaceutical company that developed brexanolone. “It’s not just the mother who suffers when there’s postpartum depression. It’s the newborn. It’s the other people in their family.”

Brexanolone is not a pill. The drug is delivered intravenously over the course of a 60-hour infusion, meaning it must be administered in a medically supervised setting, such as a skilled facility or a hospital, rather than at patients’ homes.

IMPROVEMENT IN JUST 24 HOURS

Clinical trials for the drug were promising — not just in the number of women it helped, but in the near-instantaneous relief that is provided.

In double-blind, placebo-controlled trials, many women with moderate to severe postpartum depression saw a marked improvement of their symptoms within just 24 hours of receiving the drug. That improvement was still present 30 days after the infusion, the length of the trial.

“This is for postpartum depression, but it is a step in understanding how we treat depression more broadly,” said Dr. Samantha Meltzer-Brody, director of the perinatal psychiatry program at the University of North Carolina at Chapel Hill and the academic principal investigator in the brexanolone trials. “We have had the same treatments for depression for 30 years. There’s an enormous need for new, novel ways to treat depression, and to treat it quickly.”

The drug’s approval comes just weeks after the FDA signed off on esketamine, a fast-acting nasal spray that uses the active ingredients in the club drug ketamine, as a treatment for severe depression.

For patients who are depressed, rapid relief is a priority. Hathaway, the Connecticut mother, was again diagnosed with postpartum depression after she gave birth to her second, a girl named Brenley who is now 2. This time, the antidepressants did not help at all, and Hathaway felt herself slipping deeper and deeper into a state of hopelessness.

She participated in a brexanolone trial, and her response was striking. Between hours 12 and 18 of the 60-hour infusion, she noticed her despair had waned.

“I woke up from a nap, and the thoughts were gone. And they never came back,” Hathaway said. “And then hour after hour, I got my energy back. I got my appetite back. I was eating because I was actually hungry, not because people were making me eat.”

A COMMON CONDITION

Postpartum depression afflicts as many as 400,000 women in the United States each year. It can include disturbances in sleep or eating patterns in addition to feelings of sadness or apathy. Affected women are often confused and guilt-ridden about why they are feeling down during what is supposed to be a happy time, said Dr. Christine C. Greves, an obstetrician-gynecologist at Orlando Health Winnie Palmer Hospital for Women and Babies.

“As women, we feel like we were born to have a child, and there’s a white picket fence, and life will be great,” said Greves, who does not have ties to Sage Therapeutics. “Then regular life comes into play. You have a child and then you top that with extensive fatigue, hormones, expectations that just can’t be met. It’s all fantasy until we actually have the baby. And then you do feel guilty, because we all want to be Super Mom.”

In the past decade, experts say, there has been more awareness about postpartum depression and more efforts among obstetricians and pediatricians to screen mothers for it.

But having a drug specifically aimed at treating postpartum depression will be one of the most significant steps toward removing any stigma still associated with the condition, said Dr. Kimberly Yonkers, professor of psychiatry, epidemiology and obstetrics, gynecology and reproductive sciences at the Yale School of Medicine.

“It does women a service because it really brings attention to a major medical problem and provides legitimacy, and hopefully will encourage people, whether they use this medication or not, to seek and obtain treatment,” said Yonkers, who does not have ties to the drug company. “We’re all thrilled about that.”

SOME SIDE EFFECTS, AND A HEFTY PRICE TAG

The most common side effects during the brexanolone trial were drowsiness and dizziness. The drug is not believed to have any long-term safety concerns. Kanes, Sage Therapeutics’ chief medical officer, said he expects it will be deemed safe for all mothers, including breastfeeding mothers, but the company is waiting for an FDA ruling on breastfeeding.

The drug comes with a hefty price tag: Sage says it is expected to cost somewhere between $20,000 to $35,000 for the infusion. That does not include the price of a stay in whatever facility it is administered in. It is not clear yet how much insurance would cover.

Kanes pointed out that while high, the cost is a one-time price.

“That’s such an important piece as to why this is so novel. We’re talking about a single treatment that has durable effects,” he said. “This really is a one-time intervention that gets people on their way. It’s transformative.”

For Hathaway, the brexanolone infusion enabled her to return home and be the mother to her daughters that she had wanted to be before postpartum depression took over.

“It’s given them their mom back,” she said. “This is what it was supposed to be like.”

https://www.nbcnews.com/health/womens-health/fda-approves-first-drug-postpartum-depression-n984521

Clumps of harmful proteins that interfere with brain functions have been partially cleared in mice using nothing but light and sound.

Research led by MIT has found strobe lights and a low pitched buzz can be used to recreate brain waves lost in the disease, which in turn remove plaque and improve cognitive function in mice engineered to display Alzheimer’s-like behaviour.

It’s a little like using light and sound to trigger their own brain waves to help fight the disease.

This technique hasn’t been clinically trialled in humans as yet, so it’s too soon to get excited – brain waves are known to work differently in humans and mice.

But, if replicated, these early results hint at a possible cheap and drug-free way to treat the common form of dementia.

So how does it work?

Advancing a previous study that showed flashing light 40 times a second into the eyes of engineered mice treated their version of Alzheimer’s disease, researchers added sound of a similar frequency and found it dramatically improved their results.

“When we combine visual and auditory stimulation for a week, we see the engagement of the prefrontal cortex and a very dramatic reduction of amyloid,” says Li-Huei Tsai, one of the researchers from MIT’s Picower Institute for Learning and Memory.

It’s not the first study to investigate the role sound can play in clearing the brain of the tangles and clumps of tau and amyloid proteins at least partially responsible for the disease.

Previous studies showed bursts of ultrasound make blood vessels leaky enough to allow powerful treatments to slip into the brain, while also encouraging the nervous system’s waste-removal experts, microglia, to pick up the pace.

Several years ago, Tsai discovered light flickering at a frequency of about 40 flashes a second had similar benefits in mice engineered to build up amyloid in their brain’s nerve cells.

“The result was so mind-boggling and so robust, it took a while for the idea to sink in, but we knew we needed to work out a way of trying out the same thing in humans,” Tsai told Helen Thomson at Nature at the time.

The only problem was this effect was confined to visual parts of the brain, missing key areas that contribute to the formation and retrieval of memory.

While the method’s practical applications looked a little limited, the results pointed to a way oscillations could help the brain recover from the grip of Alzheimer’s disease.

As our brain’s neurons transmit signals they also generate electromagnetic waves that help keep remote regions in sync – so-called ‘brain waves’.

One such set of oscillations are defined as gamma-frequencies, rippling across the brain at around 30 to 90 waves per second. These brain waves are most active when we’re paying close attention, searching our memories in order to make sense of what’s going on.

Tsai’s previous study had suggested these gamma waves are impeded in individuals with Alzheimer’s, and might play a pivotal role in the pathology itself.

Light was just one way to trick the parts of the brain into humming in the key of gamma. Sounds can also manage this in other areas.

Instead of the high pitched scream of ultrasound, Tsui used a much lower droning noise of just 40 Hertz, a sound only just high enough for humans to hear.

Exposing their mouse subjects to just one hour of this monotonous buzz every day for a week led to a significant drop in the amount of amyloid build up in the auditory regions, while also stimulating those microglial cells and blood vessels.

“What we have demonstrated here is that we can use a totally different sensory modality to induce gamma oscillations in the brain,” says Tsai.

As an added bonus, it also helped clear the nearby hippocampus – an important section associated with memory.

The effects weren’t just evident in the test subjects’ brain chemistry. Functionally, mice exposed to the treatment performed better in a range of cognitive tasks.

Adding the light therapy from the previous study saw an even more dramatic effect, clearing plaques in a number of areas across the brain, including in the prefrontal cortex. Those trash-clearing microglia also went to town.

“These microglia just pile on top of one another around the plaques,” says Tsai.

Discovering new mechanisms in the way nervous systems clear waste and synchronise activity is a huge step forward in the development of treatments for all kinds of neurological disorders.

Translating discoveries like this to human brains will take more work, especially when there are potential contrasts in how gamma waves appear in mice and human Alzheimer’s brains.

So far early testing for safety has shown the process seems to have no clear side effects.

This research was published in Cell.

https://www.sciencealert.com/astonishing-new-study-treats-alzheimer-s-in-mice-with-a-light-and-sound-show


The mathematically designed, 3D-printed acoustic metamaterial is shaped in such a way that it sends incoming sounds back to where they came from, Ghaffarivardavagh and Zhang say. Inside the outer ring, a helical pattern interferes with sounds, blocking them from transmitting through the open center while preserving air’s ability to flow through.

Boston University researchers, Xin Zhang, a professor at the College of Engineering, and Reza Ghaffarivardavagh, a Ph.D. student in the Department of Mechanical Engineering, released a paper in Physical Review B demonstrating it’s possible to silence noise using an open, ringlike structure, created to mathematically perfect specifications, for cutting out sounds while maintaining airflow.

“Today’s sound barriers are literally thick heavy walls,” says Ghaffarivardavagh. Although noise-mitigating barricades, called sound baffles, can help drown out the whoosh of rush hour traffic or contain the symphony of music within concert hall walls, they are a clunky approach not well suited to situations where airflow is also critical. Imagine barricading a jet engine’s exhaust vent — the plane would never leave the ground. Instead, workers on the tarmac wear earplugs to protect their hearing from the deafening roar.

Ghaffarivardavagh and Zhang let mathematics — a shared passion that has buoyed both of their engineering careers and made them well-suited research partners — guide them toward a workable design for what the acoustic metamaterial would look like.

They calculated the dimensions and specifications that the metamaterial would need to have in order to interfere with the transmitted sound waves, preventing sound — but not air — from being radiated through the open structure. The basic premise is that the metamaterial needs to be shaped in such a way that it sends incoming sounds back to where they came from, they say.

As a test case, they decided to create a structure that could silence sound from a loudspeaker. Based on their calculations, they modeled the physical dimensions that would most effectively silence noises. Bringing those models to life, they used 3D printing to materialize an open, noise-canceling structure made of plastic.

Trying it out in the lab, the researchers sealed the loudspeaker into one end of a PVC pipe. On the other end, the tailor-made acoustic metamaterial was fastened into the opening. With the hit of the play button, the experimental loudspeaker set-up came oh-so-quietly to life in the lab. Standing in the room, based on your sense of hearing alone, you’d never know that the loudspeaker was blasting an irritatingly high-pitched note. If, however, you peered into the PVC pipe, you would see the loudspeaker’s subwoofers thrumming away.

The metamaterial, ringing around the internal perimeter of the pipe’s mouth, worked like a mute button incarnate until the moment when Ghaffarivardavagh reached down and pulled it free. The lab suddenly echoed with the screeching of the loudspeaker’s tune.

“The moment we first placed and removed the silencer…was literally night and day,” says Jacob Nikolajczyk, who in addition to being a study co author and former undergraduate researcher in Zhang’s lab is a passionate vocal performer. “We had been seeing these sorts of results in our computer modeling for months — but it is one thing to see modeled sound pressure levels on a computer, and another to hear its impact yourself.”

By comparing sound levels with and without the metamaterial fastened in place, the team found that they could silence nearly all — 94 percent to be exact — of the noise, making the sounds emanating from the loudspeaker imperceptible to the human ear.

Now that their prototype has proved so effective, the researchers have some big ideas about how their acoustic-silencing metamaterial could go to work making the real world quieter.

“Drones are a very hot topic,” Zhang says. Companies like Amazon are interested in using drones to deliver goods, she says, and “people are complaining about the potential noise.”

“The culprit is the upward-moving fan motion,” Ghaffarivardavagh says. “If we can put sound-silencing open structures beneath the drone fans, we can cancel out the sound radiating toward the ground.”

Closer to home — or the office — fans and HVAC systems could benefit from acoustic metamaterials that render them silent yet still enable hot or cold air to be circulated unencumbered throughout a building.

Ghaffarivardavagh and Zhang also point to the unsightliness of the sound barriers used today to reduce noise pollution from traffic and see room for an aesthetic upgrade. “Our structure is super lightweight, open, and beautiful. Each piece could be used as a tile or brick to scale up and build a sound-canceling, permeable wall,” they say.

The shape of acoustic-silencing metamaterials, based on their method, is also completely customizable, Ghaffarivardavagh says. The outer part doesn’t need to be a round ring shape in order to function.

“We can design the outer shape as a cube or hexagon, anything really,” he says. “When we want to create a wall, we will go to a hexagonal shape” that can fit together like an open-air honeycomb structure.

Such walls could help contain many types of noises. Even those from the intense vibrations of an MRI machine, Zhang says.

According to Stephan Anderson, a professor of radiology at BU School of Medicine and a coauthor of the study, the acoustic metamaterial could potentially be scaled “to fit inside the central bore of an MRI machine,” shielding patients from the sound during the imaging process.

Zhang says the possibilities are endless, since the noise mitigation method can be customized to suit nearly any environment: “The idea is that we can now mathematically design an object that can block the sounds of anything,” she says.

https://www.sciencedaily.com/releases/2019/03/190307103109.htm

Aylin Woodward

The phrase “mass extinction” typically conjures images of the asteroid crash that led to the twilight of the dinosaurs.

Upon impact, that 6-mile-wide space rock caused a tsunami in the Atlantic Ocean, along with earthquakes and landslides up and down what is now the Americas. A heat pulse baked the Earth, and the Tyrannosaurus rex and its compatriots died out, along with 75% of the planet’s species.

Although it may not be obvious, another devastating mass extinction event is taking place today — the sixth of its kind in Earth’s history. The trend is hitting global fauna on multiple fronts, as hotter oceans, deforestation, and climate change drive animal populations to extinction in unprecedented numbers.

A 2017 study found that animal species around the world are experiencing a “biological annihilation” and that our current “mass extinction episode has proceeded further than most assume.”

Here are 12 signs that the planet is in the midst of the sixth mass extinction, and why human activity is primarily to blame.

Insects are dying off at record rates. Roughly 40% of the world’s insect species are in decline.

2019 study found that the total mass of all insects on the planets is decreasing by 2.5% per year.

If that trend continues unabated, the Earth may not have any insects at all by 2119.

“In 10 years you will have a quarter less, in 50 years only half left, and in 100 years you will have none,” Francisco Sánchez-Bayo, a coauthor of the study, told The Guardian.

That’s a major problem, because insects like bees, butterflies, and other pollinators perform a crucial role in fruit, vegetable, and nut production. Plus, bugs are food sources for many bird, fish, and mammal species — some of which humans rely on for food.

Earth appears to be undergoing a process of “biological annihilation.” As much as half of the total number of animal individuals that once shared the Earth with humans are already gone.

A 2017 study looked at all animal populations across the planet (not just insects) by examining 27,600 vertebrate species — about half of the overall total that we know exist. They found that more than 30% of them are in decline.

Some species are facing total collapse, while certain local populations of others are going extinct in specific areas. That’s still cause for alarm, since the study authors said these localized population extinctions are a “prelude to species extinctions.”

So even declines in animal populations that aren’t yet categorized as endangered is a worrisome sign.

More than 26,500 of the world’s species are threatened with extinction, and that number is expected to keep going up.

According to the International Union for Conservation of Nature Red List, more than 27% of all assessed species on the planet are threatened with extinction. Currently, 40% of the planet’s amphibians, 25% of its mammals, and 33% of its coral reefs are threatened.

The IUCN predicts that 99.9% of critically endangered species and 67% of endangered species will be lost within the next 100 years.

A 2015 study that examined bird, reptile, amphibian, and mammal species concluded that the average rate of extinction over the last century is up to 100 times as high as normal.

Elizabeth Kolbert, author of the book “The Sixth Extinction,” told National Geographic that the outlook from that study is dire; it means 75% of animal species could be extinct within a few human lifetimes.

In roughly 50 years, 1,700 species of amphibians, birds, and mammals will face a higher risk of extinction because their natural habitats are shrinking.

By 2070, 1,700 species will lose 30% to 50% of their present habitat ranges thanks to human land use, a 2019 study found. Specifically, 886 species of amphibians, 436 species of birds, and 376 species of mammals will be affected and consequently will be at more risk of extinction.

Logging and deforestation of the Amazon rainforest is of particular concern.

Roughly 17% of the Amazon has been destroyed in the past five decades, mostly because humans have cut down vegetation to open land for cattle ranching, according to the World Wildlife Fund. Some 80% of the world’s species can be found in tropical rainforests like the Amazon, including the critically endangered Amur leopard. Even deforestation in a small area can cause an animal to go extinct, since some species live only in small, isolated areas.

Every year, more than 18 million acres of forest disappear worldwide. That’s about 27 soccer fields’ worth every minute.

In addition to putting animals at risk, deforestation eliminates tree cover that helps absorb atmospheric carbon dioxide. Trees trap that gas, which contributes to global warming, so fewer trees means more CO2 in the atmosphere, which leads the planet to heat up.


In the next 50 years, humans will drive so many mammal species to extinction that Earth’s evolutionary diversity won’t recover for some 3 million years, one study said.

The scientists behind that study, which was published in 2018, concluded that after that loss, our planet will need between 3 million and 5 million years in a best-case scenario to get back to the level of biodiversity we have on Earth today.

Returning the planet’s biodiversity to the state it was in before modern humans evolved would take even longer — up to 7 million years.

Alien species are a major driver of species extinction.

A study published earlier this month found that alien species are a primary driver of recent animal and plant extinctions. An alien species is the term for any kind of animal, plant, fungus, or bacteria that isn’t native to an ecosystem. Some can be invasive, meaning they cause harm to the environment to which they’re introduced.

Many invasive alien species have been unintentionally spread by humans. People can carry alien species with them from one continent, country, or region to another when they travel. Shipments of goods and cargo between places can also contribute to a species’ spread.

Zebra mussels and brown marmorated stink bugs are two examples of invasive species in the US.

The recent study showed that since the year 1500, there have been 953 global extinctions. Roughly one-third of those were at least partially because of the introduction of alien species.

Oceans are absorbing a lot of the excess heat trapped on Earth because of greenhouse gases in the atmosphere. That kills marine species and coral reefs.

The planet’s oceans absorb a whopping 93% of the extra heat that greenhouse gases trap in Earth’s atmosphere. Last year was the oceans’ warmest year on record, and scientists recently realized that oceans are heating up 40% faster than they’d previously thought.

Higher ocean temperatures and acidification of the water cause corals to expel the algae living in their tissues and turn white, a process known as coral bleaching.

As a consequence, coral reefs — and the marine ecosystems they support — are dying. Around the world, about 50% of the world’s reefs have died over the past 30 years.

Species that live in fresh water are impacted by a warming planet, too.

A 2013 study showed that 82% of native freshwater fish species in California were vulnerable to extinction because of climate change.

Most native fish populations are expected decline, and some will likely be driven to extinction, the study authors said. Fish species that need water colder than 70 degrees Fahrenheit to thrive are especially at risk.

Warming oceans also lead to sea-level rise. Rising waters are already impacting vulnerable species’ habitats.

Water, like most things, expands when it heats up — so warmer water takes up more space. Already, the present-day global sea level is 5 to 8 inches higher on average than it was in 1900, according to Smithsonian.

In February, Australia’s environment minister officially declared a rodent called the Bramble Cay melomys to be the first species to go extinct because of human-driven climate change — specifically, sea-level rise.

The tiny rat relative was native to an island in the Queensland province, but its low-lying territory sat just 10 feet above sea level. The island was increasingly inundated by ocean water during high tides and storms, and those salt-water floods took a toll on the island’s plant life.

That flora provided the melomys with food and shelter, so the decrease in plants likely led to the animal’s demise.

Warming oceans are also leading to unprecedented Arctic and Antarctic ice melt, which further contributes to sea-level rise. In the US, 17% of all threatened and endangered species are at risk because of rising seas.

Melting ice sheets could raise sea levels significantly. The Antarctic ice sheet is melting nearly six times as fast as it did in the 1980s. Greenland’s ice is melting four times faster now than it was 16 years ago. It lost more than 400 billion tons of ice in 2012 alone.

In a worst-case scenario, called a “pulse,” warmer waters could cause the glaciers that hold back Antarctica’s and Greenland’s ice sheets to collapse. That would send massive quantities of ice into the oceans, potentially leading to rapid sea-level rise around the world.

Sea-level rise because of climate change threatens 233 federally protected animal and plant species in 23 coastal states across the US, according to a report from the Center for Biological Diversity.

The report noted that 17% of all the US’s threatened and endangered species are vulnerable to rising sea levels and storm surges, including the Hawaiian monk seal and the loggerhead sea turtle.

If “business as usual” continues regarding climate change, one in six species is on track to go extinct.

An analysis published in 2015 looked at over 130 studies about declining animal populations and found that one in six species could disappear as the planet continues warming.

Flora and fauna from South America and Oceania are expected top be the hardest hit by climate change, while North American species would have the lowest risk.

Previous mass extinctions came with warning signs. Those indicators were very similar to what we’re seeing now.

The most devastating mass extinction in planetary history is called the Permian-Triassic extinction, or the “Great Dying.” It happened 252 million years ago, prior to the dawn of the dinosaurs.

During the Great Dying, roughly 90% of the Earth’s species were wiped out; less than 5% of marine species survived, and only a third of land animal species made it, according to National Geographic. The event far eclipsed the cataclysm that killed the last of the dinosaurs some 187 million years later.

But the Great Dying didn’t come out of left field.

Scientists think the mass extinction was caused by a l arge-scale and rapid release of greenhouse gases into the atmosphere by Siberian volcanoes, which quickly warmed the planet — so there were warning signs. In fact, a 2018 study noted that those early signs appeared as much as 700,000 years ahead of the extinction.

“There is much evidence of severe global warming, ocean acidification, and a lack of oxygen,” the study’s lead author, Wolfgang Kießling, said in a release.

Today’s changes are similar but less severe — so far.

https://www.thisisinsider.com/signs-of-6th-mass-extinction-2019-3#previous-mass-extinctions-came-with-warning-signs-too-those-indicators-were-very-similar-to-what-were-seeing-now-14

Neuroscientists can read brain activity to predict decisions 11 seconds before people actFree will, from a neuroscience perspective, can look like quite quaint. In a study published this week in the journal Scientific Reports, researchers in Australia were able to predict basic choices participants made 11 seconds before they consciously declared their decisions.

In the study, 14 participants—each placed in an fMRI machine—were shown two patterns, one of red horizontal stripes and one of green vertical stripes. They were given a maximum of 20 seconds to choose between them. Once they’d made a decision, they pressed a button and had 10 seconds to visualize the pattern as hard as they could. Finally, they were asked “what did you imagine?” and “how vivid was it?” They answered these questions by pressing buttons.

Using the fMRI to monitor brain activity and machine learning to analyze the neuroimages, the researchers were able to predict which pattern participants would choose up to 11 seconds before they consciously made the decision. And they were able to predict how vividly the participants would be able to envisage it.

Lead author Joel Pearson, cognitive neuroscience professor at the University of South Wales in Australia, said that the study suggests traces of thoughts exist unconsciously before they become conscious. “We believe that when we are faced with the choice between two or more options of what to think about, non-conscious traces of the thoughts are there already, a bit like unconscious hallucinations,” he said in a statement. “As the decision of what to think about is made, executive areas of the brain choose the thought-trace which is stronger. In, other words, if any pre-existing brain activity matches one of your choices, then your brain will be more likely to pick that option as it gets boosted by the pre-existing brain activity.”

The work has implications for how we understand uncomfortable thoughts: Pearson believes the findings explain why thinking about something only leads to more thoughts on the subject, as it creates “a positive feedback loop.” The study also suggests that unwelcome visualizations, such as those experienced with post-traumatic stress disorder, begin as unconscious thoughts.

Though this is just one study, it’s not the first to show that thoughts can be predicted before they are conscious. As the researchers note, similar techniques have been able to predict motor decisions between seven and 10 seconds before they’re conscious, and abstract decisions up to four seconds before they’re conscious. Taken together, these studies show how understanding how the brain complicates our conception of free will.

Neuroscientists have long known that the brain prepares to act before you’re consciously aware, and there are just a few milliseconds between when a thought is conscious and when you enact it. Those milliseconds give us a chance to consciously reject unconscious impulses, seeming to form a foundation of free will.

Freedom, however, can be enacted by both the unconscious and conscious self—and there are neuroscientists who claim that being controlled by our own unconscious brain is hardly an affront to free will. Studies showing that neuroscientists can predict our actions long before we’re aware of them don’t necessarily negate the concept of free will, but they certainly complicate our conception of our own minds.

https://qz.com/1569158/neuroscientists-read-unconscious-brain-activity-to-predict-decisions/?utm_source=google-news