The Amazon is starting to ‘self-destruct,’ scientists warn

Only a major reforestation will save the Amazon rain forest from a complete ecosystem death, warns the leading scientific journal Science Advances. In an editorial, researchers Thomas Lovejoy and Carlos Nobre wrote that forest fires and deforestation are rapidly depleting the ecosystem’s ability to sustain itself, to the point where massive human intervention will be needed to save it.

“Although 2019 was not the worst year for fire or deforestation in the Amazon, it was the year when the extent of fires and deforestation in the region garnered full global attention,” the authors wrote. “The precious Amazon is teetering on the edge of functional destruction and, with it, so are we.”

The authors noted that the Amazon is a vital link to the global water cycle and provides crucial storage of enormous amounts of carbon dioxide. As the rain forest disappears, much of its stored water and carbon dioxide are released to the atmosphere. The carbon release further exacerbates climate change worldwide, and every country in South America except Chile would lose substantial amounts of freshwater, the authors said.

Deforestation now affects around 17% of the Amazon basin. The basin has historically been able to produce its own rainfall, due to the dense tree and foliage cover. But widespread forest depletion within the eastern and southern Amazon, in particular, hamper rainfall production for the entire basin, according to the authors. The added that human-caused global warming is already reducing rainfall throughout the region.

The basin is responding by changing in fundamental ways, they wrote: lengthier and hotter dry seasons, and the trees increasingly being replaced by tree species that favor drier climates.


Scientists try to revive coral reefs with fish-enticing audio

Loudspeakers that play sounds intended to attract fish are helping to bring dead coral reefs back to life, according to a paper published recently in Nature Communications. The paper’s authors said that they hope that their findings could lead to efforts undo much of the mass destruction of coral that has been taking place throughout the world’s oceans in recent decades.

In the paper, the researchers described placing underwater loudspeakers at locations in a zone of ocean water north of Australia. Each site was within a formerly vibrant coral reef that had largely died out.

The speakers played sounds associated with healthy, vibrant reefs; the researchers intended for fish to hear these recordings and flock to the sites to breed. Their plan worked: The sites that had the speakers saw 50% increases in both the numbers of fish and numbers of fish species.

New fish populations won’t directly create more coral, but they can encourage new coral growth as the fish clean reef surfaces and create more spaces for corals to grow, the researchers said. Andy Radford, a paper coauthor from the University of Bristol, said that efforts such as this one to boost fish populations can be important parts of larger initiatives to bring lost coral ecoysystems back to life.

“If combined with habitat restoration and other conservation measures, rebuilding fish communities in this manner might accelerate ecosystem recovery,” said Radford.

Ocean researchers have been concerned about coral health throughout the world’s oceans in the last few decades, due to widespread deaths of coral in many locales. The main driving force behind coral death is climate change: Ocean water becoming incresaingly acidic as it absorbs larger amounts of carbon dioxide from the atmosphere, according to researchers.


Opioid alternatives increase risk of suicide

As doctors increasingly prescribe fewer opioids and instead give their patients non-opioid alternatives for chronic pain, research suggests that the non-opioids have deadly side effects of their own. A study concludes that non-opioids Gabapentin and Baclofen are fueling rising rates of suicides.

The study, published in the journal Clinical Toxicology, examined data from the U.S. Poison Centers for the National Poison Data System, focusing on cases involving Gabapentin between 2014 and 2017 and cases involving Baclofen between 2013 and 2017. In these time periods, according to the researchers, suicide attempts rose 80.5% among patients taking Gabapentin and 43% among patients taking Baclofen.

Around 50 million adults–roughly 20% of the U.S. population–suffers from chronic pain. Opioid drugs can relieve pain, but doctors have been steering away from them in the face of surging rates of opioid overdose deaths in recent years. Gabapentin, an anti-epileptic drug that also treats nerve pain; and Baclofen, a muscle relaxant and antispasmodic drug that relieves muscle spasms, pain, and stiffness, have gone into increased use as alternatives.

Suicide rates in general have risen nationwide by 30% between 1999 and 2016, the study authors noted. They also pointed out that both drugs list sucidal thoughts as a potential side effect. The authors noted rising prescription rates for both drugs in recent years and cautioned doctors to weigh the potential dangers of these drugs, as well.

“Building a better understanding of the risks carried by these non-opioid medications is necessary so that providers and patients can make better-informed decisions about their role in pain management—and could also lead to the introduction of new public health measures,” said Kimberly Reynolds, a University of Pittsburgh researcher who led the study.


Car crashes are rising fast in states where marijuana is legal

Car accidents have spiked in the first three states to legalize recreational marijuana, as law enforcement and state lawmakers grapple with how to define marijuana-impaired driving and test drivers for marijuana. It is much more complex than enforcing laws against driving drunk, analysts said.

Colorado, Washington, and Oregon saw a combined 5.2% increase in the rate of police-reported car crashes after marijuana legalization, compared with neighboring states where marijuana is still illegal, according to researchers from the Highway Loss Data Institute, who compiled and analyzed data from the Insurance Institute for Highway Safety. The researchers also found that auto-insurance collision claims increased a combined 6% across all three states since legalization, compared with neighboring states.

Other organizations are voicing worry over the issue. The Washington Traffic Safety Commission said that the number of drivers involved in fatal crashes in the state who tested positive for THC, the psychoactive chemical in marijuana, more than doubled since 2013. Recreational sales of marijuana first occurred legally in Washington in 2014.

Helen Witty, president of Mothers Against Drunk Driving, said that “Drunk driving is still the No. 1 killer on our roads. … But drugged driving, as it’s legalized across this country, is a huge, emerging issue.”

Researchers said that policing against marijuana-impaired driving is difficult as there is no official legal definition of it, nor is there any recognized breathalyzer-like system for reliably detecting marijuana in a driver’s breath or blood. The presence of marijuana in blood also does not necessarily indicate impairment, and THC can disappear from the bloodstream in as little as a half-hour, making it difficult to capture incriminating evidence from even a driver who has consumed marijuana, said Staci Hoff, research director at the Washington Traffic Safety Commission.

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Archaeologists unearth long-lost Aztec tower of skulls

Archaeologists digging in Mexico City have unearthed the long-fabled Huey Tzompantli — a tower of human skulls thought to measure about 200 feet in diameter.

The tower was described in contemporary accounts of the Spanish conquistadores when they captured the Aztec capital of Tenochtitlan, which later became Mexico City.

The tower is located at the edge of the Templo Mayor, an edifice dedicated to the Aztec god of sun, war, and human sacrifice, according to a report by The Atlantic.

In the account of Andres de Tapia, a Spanish follower of Hernan Cortes during his conquest of Mexico in 1521, the tower was constructed of tens of thousands of skulls “placed on a very large theater made of lime and stone, and on the steps of it were many heads of the dead stuck in the lime with the teeth facing outward.”

What the archaeologists did not expect to find were so many skulls belonging to women and children. Researchers previously believed that young male warriors were mostly chosen as sacrificial victims. As a result, the discovery is raising new questions about the Aztec Empire’s culture of human sacrifice.

“We were expecting just men,” said Rodrigo Bolanos, a biological anthropologist working on the dig, in a report by Reuters, adding, “Something is happening that we have no record of, and this is really new, a first in the Huey Tzompantli.”

So far, researchers have discovered more than 650 skulls that were covered in lime to cement them together. Only a quarter of the excavation is completed.

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Archaeologists find slave quarters of Sally Hemings at Monticello

Archaeologists have discovered the living quarters of Sally Hemings — the enslaved African American woman who bore six of Thomas Jefferson’s children — at Jefferson’s Monticello estate. The room, 13 feet long and just under 15 feet wide, was adjacent to Jefferson’s bedroom.

Thomas Jefferson wrote the Declaration of Independence and was the third president the United States.

“This discovery gives us a sense of how enslaved people were living,” said Gardiner Hallock, director of restoration for Monticello, in a report by NBC News. “Some of Sally’s children may have been born in this room.”

Historians hit on a possible location for Hemings’ living quarters by studying a description related by one of Jefferson’s grandsons, who said Hemings’ room was in Monticello’s south wing.

Monticello’s director of archaeology, Fraser Neiman, said digging revealed the original brick fireplace, hearth, and early 19th century floors.

“This room is a real connection to the past,” Neiman said. “We are uncovering and discovering and we’re finding many, many artifacts.”

Gayle Jessup White is Sally Hemings’ great-great-great-great niece and also works at Monticello’s Community Engagement Officer.

“As an African American descendant, I have mixed feelings — Thomas Jefferson was a slave holder,” White said, in the NBC News report. I am appreciative of the work that my colleagues are doing at Monticello because this is an important American story. But for too long our history has been ignored. Some people still don’t want to admit that the Civil War was fought over slavery. We need to face history head-on and face the blemish of slavery and that’s what we’re doing at Monticello.”

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5.7-million-year-old “human footprints” stun paleontologists

An analysis of a set of human-like footprints in ancient rock beneath Crete has researchers baffled due to one critical detail: The rock is 5.7 million years old. There were not supposed to be fully evolved humans in Crete—or anywhere on Earth, for that matter—until less than a million years ago, according to the scientific consensus.
Gerard Gierlinski of the Polish Geological Institute found the footprints in 2002 and spent the next decade-and-a-half analyzing them before publishing the results just this month in the latest edition of Proceedings of the Geologists’ Association. The study notes numerous human-like features in the footprint: five toes, including a big toe similar to ours, as well as a distinct ball on the sole. There is also evidence of an upright posture and toenails instead of claws.
None of these features were supposed to appear for another four million years, at least, according to researchers. Also, there were not supposed to be any humans or apelike ancestors of humans anywhere outside Africa.
Until now, the earliest known footprints of hominids that show upright posture date back 3.7 million years ago and are located in present-day Tanzania. There is an earlier set of footprints dating back 4.4 million years ago, but its discoverers said that it very closely resembles an ape’s footprint and shows none of the human-like traits of Gierlinski’s find.
Gierlinski posits that there was another human-like creature that was roaming the Earth eons before any of the known hominids. This creature might have likewise made it to present-day Crete long before any currently known hominids left the African savanna.
“As Crete is some distance outside the known geographical range of pre-Pleistocene (2.5 million to 11,700 years ago) hominins we must also entertain the possibility that they represent a hitherto unknown late Miocene primate that convergently evolved human-like foot anatomy,” the study states.

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African dogs use sneezes to make pack decisions

African wild dogs use sneezing as a way to determine how many members of the pack are ready to move and hunt, according to a new study published in the Proceedings of the Royal Society B.

There are many ways animals communicate, but there is no doubt this is one of the more unusual. Researchers first noted the behavior while conducting a separate study on the dog’s characteristics.

Researchers found that the more sneezes — or “audible rapid nasal exhalations” — the dogs emitted, the more likely the pack would be to set out on its next hunt. The team came to this conclusion after watching five packs in Botswana engage in a total of 68 gatherings.

Not only are the sneezes used for communication, but they differ based on an individual dog’s social standing as well.

“Rallies never failed when a dominant…individual initiated and there were at least three sneezes, whereas rallies initiated by lower ranking individuals required a minimum of 10 sneezes to achieve the same level of success,” stated the study’s authors, according to NPR.

However, while this process is interesting, the sneezes are hard to properly analyze because they do not count as true votes. This is because each dog is not limited to one sneeze and scientists are not sure if each one is voluntary or some are a natural reaction.

Even so, the findings are important because they shed light on a new process. While the dominant members of a pack hold more power than others, every member has a say in certain decisions depending on how many sneezes they can muster.

African wild dogs are not the only species that makes unique sounds to help with decision making, but they are the only one that uses sneezing as their voting method. Researchers seek to follow up on the study by looking at other animals, and they hope the new findings will bring light to the canines, which are one of the most endangered species in the world.

“They’re absolutely gorgeous animals focused on cooperation and their pack family unit,” says study co-author Reena Walker, a student at Brown University, according to National Geographic. “The more people who are aware [of] how amazing these animals are, the better.”


A first: Micromotors used to treat stomach infection

For the first time, nanoengineers have successfully used micromotors — tiny magnesium-based engines no bigger than half the width of a human hair — to treat a bacterial infection in the stomach, according to a statement by the University of California at San Diego’s Jacobs School of Engineering.

The findings are published in the Aug. 16 issue of the journal Nature Communications.

The micromotors are released into the stomach where they swim about rapidly neutralizing gastric acid and releasing antibiotics. Each micromotor has a round magnesium core and is fueled by the reaction of gastric acid with the magnesium, which produces a blast of tiny hydrogen bubbles that propels the micromotor around inside the stomach.

The micromotors are biodegradable and the magnesium cores along with their binding polymer layers are dissolved by the stomach’s gastric acid without harmful effects.

Delivery of drugs to neutralize gastric acid and treat bacterial infections, such as ulcers, by micromotors avoids the use of proton pump inhibitors, which currently are employed to suppress gastric acid production but have several unwanted side effects, including diarrhea, headaches, and depression.

“It’s a one-step treatment with these micromotors, combining acid neutralization with therapeutic action,” said co-first author Berta Esteban-Fernández de Avila, a postdoctoral scholar at UC-San Diego.

The researchers tested the micromotors — loaded with a dose of the antibiotic clarithromycin — in mice infected with Heliobacter pylori. They gave the mice one antibiotic-filled micromotor once daily for five consecutive days.

Once the treatment regimen was complete, analysis of the bacterial count in each mouse’s stomach showed that treatment with micromotors was slightly more effective than conventional treatment using proton pump inhibitors.

While the work is still at an early stage, the results look promising, according to the researchers, who say their work opens the door to the use of micromotors as delivery vehicles for the treatment of diseases.

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5.7 million-year-old fossil footprints from Crete shake up theories of human evolution

Scientists working on the Greek island of Crete have found distinctly human-like footprints that are 5.7 million years old — a discovery that is challenging accepted theories of human evolution because they date back long before human ancestors are thought to have left Africa.

The footprints, found embedded in rock in an area called Trachilos in western Crete, show that the creature was bipedal, had five toes, and sported an especially human-like big toe that is similar to those of modern humans in size, shape, and position.

The research is published in the journal Proceedings of the Geologists’ Association.

“Human feet have a very distinctive shape, different from all other land animals,” wrote Uppsala University, in a statement. “The combination of a long sole, five short forward-pointing toes without claws, and a hallux (“big toe”) that is larger than the other toes, is unique.”

By contrast, the 3.7 million-year-old Laetoli footprints from Tanzania, believed to have been made by Australopithecus, lack arches and have narrower heels than modern humans, while the 4.4 million-year-old Ardipithecus ramidus from Ethiopia has a more ape-like foot.

“What makes this controversial is the age and location of the prints,” says co-author Prof. Per Ahlberg of Uppsala University, in the statement.

When the Trachilos footprints were made, during the late Miocene, Crete was still attached to the Greek mainland and savannah-like environments stretched from North Africa around the eastern Mediterranean.

“This discovery challenges the established narrative of early human evolution head-on and is likely to generate a lot of debate,” says Ahlberg. “Whether the human origins research community will accept fossil footprints as conclusive evidence of the presence of hominids in the Miocene of Crete remains to be seen.”