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The Fight to Return An Iconic Skull to Zambia

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Kabwe Skull

The Kabwe skull. (Credit: Copyright of the Trustees of the NHM)

The town of Kabwe sits about 70 miles north of Zambia’s capital, Lusaka, as the crow flies. Just over 200,000 people live in this major transportation crossroads. Like most of this south-central African nation, Kabwe is perched on a high and vast plateau, a land of red soils dotted with shrubby legumes and canopies of small, spindly miombo trees.

Kabwe’s story is defined in part by a mine that opened in the early 1900s after rich deposits of lead and zinc were discovered on the edge of the town. Kabwe—then called Broken Hill—became a major mining center, producing profits for British interests and, later, important metals for the Allies in both world wars. At that time, Zambia was known as Northern Rhodesia, after British mining magnate Cecil Rhodes, whose name has come to symbolize the worst evils of his nation’s colonialism.

The mine shut down in 1994 after its deeper deposits of zinc and lead were exhausted, 30 years after Zambia achieved its independence. But it left the town with a toxic legacy of lead contamination. Recent studies have found that nearly all of Kabwe’s children have blood lead levels so high that their health is in serious danger. Environmentalists consider Kabwe to be one of the most polluted cities on Earth. And they are concerned by reports that the Zambian government has given the international minerals company, Jubilee Metals Group, based in London, permission to begin collecting lead and zinc from surface deposits this year.

Yet the Kabwe mine also left a happier legacy, one that all of humankind can celebrate: In 1921, miners working there discovered a fossilized skull of a possible human ancestor, along with some other bones thought to be associated with it. Dubbed “Rhodesian Man,” this hominin may occupy a pivotal place in the evolutionary transition from Homo erectus to Homo sapiens. Today anthropologists refer to the find as the “Kabwe skull” and recognize it as the first early human fossil discovered in Africa, found at a time when most scientists were looking to Asia or even Europe for the origin of our species.

Soon after its discovery, mining officials sent the fossils to the British Museum for study. In subsequent years, the skull and other remains stayed in the U.K., and today they reside in London’s Natural History Museum. The Zambians have been trying to get them back for decades, to no avail.

The U.K. has a reputation for fiercely resisting the return of antiquities acquired during colonial times, especially tourism-generating treasures like the Parthenon sculptures (a.k.a. Elgin marbles) from Greece and the Rosetta stone from Egypt. But last May, at a meeting of the United Nations Educational, Scientific, and Cultural Organization (UNESCO) heritage committee in Paris, Zambian representatives finally broke through British resistance. The United Kingdom agreed to sit down and talk about the possible repatriation of the skull and related fossils back to Zambia.

British and Zambian officials are being tight-lipped about the upcoming negotiations, citing their sensitive diplomatic nature. Yet the decision to discuss repatriating the skull fits a more recent pattern wherein former colonial powers have begun returning cultural artifacts and human remains to Indigenous peoples. Examples include Germany’s return to Namibia of the remains of more than 25 victims of a colonial-era genocide, including 19 skulls that had been taken out of Africa in the early 20th century for “anthropological” research; France’s return of the remains of Saartjie Baartman (also known as “Hottentot Venus”) to South Africa for proper burial; and the Smithsonian Institution’s repatriation of human remains to New Zealand and to Native American tribes in the United States.

herero woman

A Herero woman. Members of the ethnic group are fighting to have the remains of ancestors murdered during a genocide returned to them. (Credit: Rostasedlacek/Shutterstock)

If Britain agrees to return the remains of the Rhodesian Man, it could provide a major boost, the Zambians say, to their national identity and would represent a major victory for repatriation efforts worldwide. At stake are key issues about the rights of former colonies to control their own heritage, and the responsibilities of former colonial powers to own up to the sins of the past.

On June 17, 1921, a Swiss miner named Tom Zwigelaar and a young African miner, working at Broken Hill, uncovered the Rhodesian Man. We owe details of the discovery to Aleš Hrdlička, a famed anthropologist at the Smithsonian Institution, who traveled to Northern Rhodesia to gather more information about the exact location where the skull had been found.

Hrdlička spoke with Zwigelaar himself, who was still working at the mine, about the find. “[Zwigelaar] was found to be a serious middle-aged man, not highly educated but of good common sense,” Hrdlička wrote in a 1926 issue of the American Journal of Physical Anthropology.

Zwigelaar told Hrdlička that he was working with an African miner—whose name was never recorded—at about 10 a.m. that June morning in a pocket of the mine with a lot of lead ore. “After one of the strokes of the pick, some of the stuff fell off, and there was the skull looking at me,” Zwigelaar told him. Hrdlička’s paper included a photo, taken by the mine’s manager shortly after the discovery, of Zwigelaar leaning against the mine shaft holding the skull on the palm of his outstretched left hand.

The skull didn’t stay in Northern Rhodesia for long. A doctor at the Broken Hill Hospital examined it and immediately suspected its scientific importance. About five months later, the Rhodesia Broken Hill Mine Company shipped it off to England, donating the find to the British Museum in London. There, the museum’s keeper of geology, renowned paleontologist Arthur Smith Woodward, named it Homo rhodesiensis. Woodward and other scholars recognized that the skull, with a brain size of about 1,300 cubic centimeters—within the range of H. sapiens—was an important human ancestor. Many anthropologists today classify the skull as belonging to the species Homo heidelbergensis, a descendant of H. erectus. Some researchers think H. heidelbergensis is, in turn, the common ancestor of modern humans and Neanderthals.

kabwe skull

Discovered in 1921, the Kabwe skull belonged to a hominid who lived some 300,000 years ago. (Credit: British Museum/Wikimedia Commons)

Over the years, the “Kabwe skull” has continued to attract scientific attention, especially because it is one of the best-preserved hominin fossils from its time period of roughly 300,000 years ago. That timing coincides with when human evolution experts think H. sapiens diverged from more archaic hominins in Africa. Thus, the Kabwe skull—which includes ancient features such as prominent brow ridges and modern features such as a globular-shaped brain case—could represent a transitional step in human evolution.

In 2016, scientists sampled it for ancient DNA, although so far attempts to sequence even part of the Rhodesian Man’s genome have been unsuccessful. In just the past two years, at least 10 papers have been published about the fossils, many based in whole or in part on CT scanning data from the skull. These studies seem to confirm the skull is a descendant of the earlier H. erectus, but its relationship with later humans, such as H. sapiens and the Neanderthals, is still a matter of debate. Researchers at the Natural History Museum are trying to help resolve this mystery by dating the skull more precisely using modern methods.

Zambia achieved its independence from Britain in 1964. A decade later, the young nation began trying to get the Kabwe skull and associated bones back, but the British government either rejected or ignored its requests.

In recent years, Zambian researchers and cultural officials have left a paper trail of detailed and eloquent arguments—citing moral grounds and international law on cultural artifacts and human remains—for the return of the Kabwe skull. In many ways, the case for repatriation echoes that made by Native Americans under the 1990 Native American Graves Protection and Repatriation Act, which provides for the return of artifacts and human remains under certain defined conditions.

Key to Zambia’s position is a colonial law from 1912 called the Bushman Relics Proclamation. Zambia interprets the proclamation to mean that no cultural artifacts or human remains could be removed from Northern Rhodesia without a permit from the British South Africa Company, which at that time was chartered by the British government to administer the protectorate. The Zambians insist that no such permit was ever issued to the Broken Hill mining company when it donated the skull to the British Museum.

In a 2013 paper in the African Archaeological Review, which chronicles some of this history, Zambian historian Francis Musonda contended that the removal of the skull from Zambia occurred in a colonial context that is anachronistic today. (Greece has made similar arguments for the return of the Parthenon sculptures housed in the British Museum.)

parthenon marbles

The Parthenon Marbles. (Credit: Giannis Papanikos)

“African people find it unacceptable for a British institution to provide a repository for an African fossil when they themselves have the capacity to do so,” Musonda wrote. “This has put the country in an embarrassing and awkward position because of the impression created that it is incapable of looking after its own hominin fossil.” And even if the conditions in Zambia were “not ideal,” Musonda argued, “why not assist the country in creating conditions deemed suitable for the object?”

It is still unclear when the actual negotiations between Zambia and the U.K. will begin, and Zambian officials have expressed some frustration at the delays—both in the Zambian press and to SAPIENS. In the meantime, writes Flexon Mizinga, executive secretary of the National Museums Board of Zambia, in an email, “it would be premature to make any statements on this matter before exhausting consultations in progress with the Government of Zambia.” Mizinga adds that “we wouldn’t want to jeopardize the multilateral issues involved.”

A spokesperson for the U.K.’s Department for Digital, Culture, Media, and Sport was equally circumspect, only confirming the UNESCO agreement and that it was expected to lead to “discussions to find a mutually acceptable solution to the Broken Hill skull case.”

Nevertheless, the news did get considerable coverage in the Zambian press, and on June 1, 2018, the Zambian delegation in Paris put out a detailed statement hailing the diplomatic breakthrough.

In email correspondence, numerous human evolution researchers expressed sympathy with Zambia’s position. “We should all support repatriation of cultural objects looted or taken away, for whatever reason, from any country in the world,” writes Yohannes Haile-Selassie, curator of physical anthropology at the Cleveland Museum of Natural History.

“The pride that Africans feel about ancestry is unwavering and pronounced,” writes Wendy Black, curator of pre-colonial archaeology at the Iziko Museums of South Africa in Cape Town. “For Africans, repatriation of these items is viewed as part of a healing process, where all parties concerned can make amends, forgive, and move on.”

CT scan Kabwe

A CT scan of the Kabwe skull shows the fine structure of its internal features, which can be compared evolutionarily to other ancient skulls. (Credit: Bruner & Manzi/The Anatomical Record)

Haile-Selassie, an Ethiopian who is active in paleoanthropological research in his native country, points out that the key question is who will have control—not only of the actual skull but also the CT scans and other digitalized information that have been gathered on the specimen over many years. That information, which the Natural History Museum now considers its intellectual property, should be under Zambia’s control, he contends.

Another issue is access, which human evolution researchers are eager to maintain. “It is an aesthetically beautiful specimen,” writes Leslie Aiello, president of the American Association of Physical Anthropologists. Aiello, formerly at the University College London and a past president of the Wenner-Gren Foundation, which funds SAPIENS, adds that “while in London, I used to ask them to get it out occasionally just so I could admire it!”

Some researchers think that before the Kabwe skull is repatriated, certain conditions should be met to ensure that scientists will be able to access and study it in the future. Gerhard Weber, an anthropologist at the University of Vienna in Austria who has studied CT scans of the skull, writes that even if it is scanned and digitalized with “the best resolution possible” before it leaves London, “this will only help for a limited time. … There will be new methods in 20, 50, or 100 years that we cannot even imagine today.” Weber suggests that agreements should be negotiated with Zambia that guarantee access to the skull so that novel techniques can be applied. He also thinks an international committee should monitor these agreements.

But Black and others don’t see any inherent barriers to access if Zambia gets the Kabwe skull back. “Researchers travel to Africa all the time,” Black maintains. “Museums in South Africa and Kenya, for example, provide access to their collections to numerous researchers from around the world each year. … One could apply for access, as all researchers do at all institutions.”

Furthermore, writes Rebecca Ackermann, a biological anthropologist at the University of Cape Town in South Africa, “a move to Lusaka would certainly make it easier for African researchers to study the remains.” Indeed, the Kabwe skull, discovered when Zambia was still under colonial rule and then whisked out of the country, is an outlier; most hominin fossils discovered in Africa—such as Ethiopia’s “Lucy” and the many fossils found in Kenya, Tanzania, and South Africa—have remained in their countries of origin.

Ackermann and others contend that non-African researchers and museums must be willing to loosen their grips on the spoils of the colonial past, even ones that are vital to our understanding of human origins. “There has been a whole lot of taking and comparatively little giving back,” she contends. Keeping the skull in British—not Zambian—hands, she argues, perpetuates a colonial legacy. “Any claim that Zambians can’t take responsibility for their own heritage is frankly racist.”

 

Michael Balter is a freelance writer and reporter based in the New York City area.

This work first appeared on SAPIENS under a CC BY-ND 4.0 license. Read the original here.

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Ecology

What if a jolt of electricity could make you happy?

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Scientists found a way to literally spark joy using joly of electricity. (Credit: icon99/shutterstock)

Scientists found a way to literally spark joy using jolts of electricity. (Credit: icon99/shutterstock)

People all around the world (or at least where Netflix is available) have been exhausting themselves of late trying to “spark joy” in their lives. The urge comes from cleaning guru Marie Kondo, whose philosophy rests on the principle that we should rid our homes and minds of things that don’t inspire bursts of pleasure.

The message resonates, in part, because it ties positivity to the world of material things. Happiness is in our minds. So having a tangible mechanism for producing joy is understandably comforting.

But there’s a simpler way to spark joy, if we really want to get literal about it. Any emotion we feel has a physical cause inside our brains. Electrical charges pass from neuron to neuron, spreading ripples of thought and feeling. What we call happiness is just electricity. And now researchers say they’ve found a remarkably specific means of triggering the electrical fireworks that add up to happiness in our brains. By electrically stimulating a brain region known as the cingulum, scientists created spontaneous laughter and a sense of calm and joy in three different patients.

The find could lead to treatments for anxiety and depression, and it hints at insights into the very roots of our emotions themselves.

An artist's illustration shows how an electrode tapped into the cingulum. (Credit: From Bijanki et al, J. Clin. Invest. (2019). Courtesy of American Society for Clinical Investigation)

An artist’s illustration shows how an electrode tapped into the cingulum. (Courtesy of American Society for Clinical Investigation)

Unexpected Bliss

The young woman is clad in hospital garb, sitting upright in a bed. A white hospital cap mushrooms above her head, wires splay from its rear. She’s due for brain surgery in a few days to treat a difficult, disruptive kind of epilepsy. She’s been worried and anxious.

She breaks into a radiant smile, laughter flowing uninhibited.

“I’m kind of like smiling because I can’t help it,” she says. A bit later, “Sorry, that’s just a really good feeling. That’s awesome.”

Neuroscientists just administered a tiny jolt of electricity to wires threaded through her skull and into her brain. The wires are there to guide surgeons to the source of her seizures. But before the procedure, she’s agreed to play guinea pig to a team of Emory University researchers.

Patients like her offer an unprecedented opportunity for researchers to test the workings of various brain regions with unparalleled specificity. By delivering targeted bursts of electricity through the electrodes, they can watch what happens when specific neural circuits are activated.

The team was sending small bursts of electricity to her cingulum, a horseshoe of brain matter that links to regions associated with emotion, self-assessment, social interaction and motivation, among other things. It’s also known to regulate anxiety and depression.

This kind of research, though hardly common, is not new. The patient’s reaction is.

“It was really exciting,” says Kelly Bijanki, a neuroscientist at Emory University who studies behavioral neuromodulation. She was one of the scientists working with the young woman, whose name was not given for privacy reasons, that day. She says the kind of spontaneous joy she saw was unprecedented.

Experiments with brain stimulation have elicited laughter and smiles before. But those responses seemed mechanical. Bijanki says the patients usually described it as a purely motor response. “Their body has laughed, but there’s no content to it.”

This case was different. There was real warmth behind the laughter; true happiness in her voice. At one point, the patient reported she was “so happy she could cry,” the researchers write in their paper.

“The way she was laughing was really infectious,” Bijanki says. “The whole room felt different: she was laughing, she was having a good time, and not afraid. Just that social, emotional contagion took over.”

Further tests confirmed the response. They conducted sham trials, telling the patient that they were providing stimulation when they weren’t. She didn’t react. They tested various levels of stimulation and saw that the more electricity they delivered, the stronger the joyous reaction was. The pattern remained the same: An initial burst of exultation faded into a state of happy relaxation after several seconds.

The researchers found no drawbacks to the treatment, either, they report in a paper in the Journal of Clinical Investigation. Her language skills and memory remained perfectly intact, and they saw no ill aftereffects of the stimulation.

In a screengrab from the scientists' experiment, the patient feels overwhelming joy even while pondering her dog dying. (Credit:)

In a screengrab from the scientists’ experiment, the patient feels overwhelming joy even while pondering her dog dying. (Credit: Bijanki et al, Journal of Clinical Investigation)

Put to the Test

The woman’s impending surgery would require her to remain awake while surgeons probed inside her skull. Their goal was to cut out the tissue responsible for her epilepsy, but it’s a game of millimeters. Doctors must remove enough to ensure that seizures don’t recur, but without causing permanent harm. The patient’s seizures appeared to emanate from a region near to language processing centers. Her job was to stay awake while surgeons worked, reading and talking to ensure they wouldn’t excise anything important.

The brain stimulation turned out to work so well that doctors were able to cut out completely the drugs used to manage anxiety during this type of brain surgery. Those medications can make patients sleepy and unresponsive, so the anesthesiologist decided to stop them midway through. The young woman, her skull opened to surgical tools, breezed through.

“During the surgery … she was telling me jokes about her dad, where prior to turning on the stimulation she had been crying and hyperventilating and right on the edge of panic,” Bijanki says.

To confirm their findings, the researchers performed the same tests with two more epilepsy patients with electrodes similarly implanted in their skulls. They got the same results. Jabs of electricity literally sparking joy inside their heads.

Putting Happiness to Work

It’s too simplistic to say the researchers have stumbled upon the place where joy hides within us. The brain is complex, and emotions well up from more than just a single place. Multiple brain regions are involved, and each contributes a facet to the emotion that we come to know as happiness.

In fact, researchers have found joy in another place in the brain as well. Sameer Sheth, a neurosurgeon at the Baylor College of Medicine, says that he’s had patients report feelings of euphoria during the course of his own work with brain stimulation as well. He was working with the ventral striatum, a region separate from the cingulum, though the two are tightly connected.

Stimulation to the ventral striatum has also produced the same sort of laughter and mood elevation that Bijanki saw, Sheth says.

But just because emotions are neurologically complex doesn’t mean there’s no value to understanding their origins.

“The more we understand this circuitry, the more we can fine tune how to harness that capability within an individual and the better we’ll be able to treat patients with mood disorders,” Sheth says.

Bijanki sees a range of applications for brain stimulation aimed at specific targets, beginning with the kind of surgeries the young epileptic was undergoing. By precluding the use of sedatives, the find might give brain surgeons new options when performing the kind of procedures the young woman went through. Allowing patients to give more feedback could make brain surgeries more targeted. It might also expand the scope of neurosurgery.

“The definition of what is an inoperable tumor is in some circumstances related to what is the surgeon reasonably comfortable with removing that isn’t going to ruin the patients life,” Bijanki says. “If the surgeon could know that in real time, then the surgery could proceed a little bit differently.”

More broadly, it could also find use as a treatment for mental disorders like depression, anxiety and PTSD. Bijanki imagines electrodes powered by a pacemaker battery delivering continuous, low-grade stimulation to patients with depressive disorders.

In the future, we may not even need wires to spark such emotions. Scientists are developing means of activating brain regions with pulses of light, or with ultrasound. Flashes and vibrations could one day deliver ease to the afflicted.

There are drugs that accomplish similar things today, of course, but those often have side effects, and the treatment isn’t always as direct. Brain stimulation could offer a better path.

Banish the Sadness

Bijanki was also struck by an odd side-effect of the stimulation. Though patients had no trouble recalling sad memories during treatment, the recollections were wholly powerless to make them feel unhappy.

“I remember my dog dying, and I remember that it was a sad memory, but I don’t feel sad about it right now,” the young woman said, as reported by the researchers in their paper. Another patient concurred, unable to recollect a tragic memory without smiling. The effect is slightly jarring, but it could provide a shield of sorts to those overcoming trauma.

Those suffering from PTSD often go through what’s called exposure therapy, where they are asked to repeatedly sift through memories of a traumatic event. The goal is to drain those memories of their fearsome power over time, but it is difficult, frightening work.

Paired with temporary brain stimulation that elides sadness, Bijanki thinks PTSD patients might be far better equipped to tread through painful memories.

Finding Balance

Ultimately, however, the goal of therapies involving brain stimulation isn’t to wipe out negative emotions.

Anger, sadness and fear are not without their merits, and banishing them could have unintended consequences. Sadness sits at the other end of the spectrum from happiness, for example. Taking away any of our emotions would be removing an aspect of our humanity. What’s more, we have emotions for a reason.

“Our emotions exist for a very specific purpose, to help us understand our world, and they’ve evolved to help us have a cognitive shortcut for what’s good for us and what’s bad for us,” Bijanki says.

That’s not the goal here, of course, though discussions about the ethical use of such technologies in the future is certainly warranted. Bijanki says that we’d need to be careful about applying things like brain stimulation that could be abused.

But, she’s not very worried about electrodes and electric shocks becoming the next designer drug. It’s just too technically demanding, she says. And the potential benefits for those with depression and other conditions are great.

Sometimes the bad can outweigh the good. In those cases, sparking a little joy might be what we need.

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NASA Picks Science Experiments to Send to the Moon This Year

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Virgin Galactic’s SpaceShipTwo Just Made its Second Trip to Space

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SpaceShipTwo under rocket power

SpaceShipTwo is carried into the air on the back of a plane, but then takes off into space under its own power. (Credit: Virgin Galactic)

On Friday, Virgin Galactic’s SpaceShipTwo flew in space for the second time, taking off from Mojave, California after days of weather delay. SpaceShipTwo took off at 8:07 a.m. PST carrying two pilots, a crewmember, and a nearly full weight of science projects from NASA.

Unlike most spaceflights that fire rockets from the ground, SpaceShipTwo is carried on the belly of a plane named WhiteKnightTwo before being released to propel itself into the upper atmosphere. After being carried 45,000 feet into the air, SpaceShipTwo successfully fired its rocket engine and reached suborbital space at approximately 8:55 a.m. PST. It coasted there for only a few minutes before heading back toward the ground, where it landed much like any other plane, roughly an hour after takeoff. Like all of SpaceShipTwo’s planned flights, this one was suborbital, meaning it does not reach orbit, and attains weightlessness for only a few minutes during its trip.

SpaceShipTwo made its maiden space voyage in December 2018, and today was its fifth powered flight in total. Unlike other private spaceflight companies like SpaceX, Virgin Galactic has made their main goal ferrying private citizens into space, and have been taking reservations for years.

The third crewmember today was Virgin Galactic’s Chief Astronaut Instructor and cabin evaluation lead. Her job today was to see how SpaceShipTwo feels from the cabin. Eventually, Virgin Galactic hopes to seat six passengers in place of the science payloads – or alongside them.

The spacecraft today also carried research projects from NASA’s Flight Opportunities program, which pairs research institutions with private companies who can fly their projects into space. The combined weight of the payloads put SpaceShipTwo at close to, but just under, the requirements for the commercial launch weight that NASA has specified. One of Virgin Galactic’s goals during this flight was testing how the vehicle flies with a greater weight distribution. Details will likely come later, but the flight was successful, which bodes well for the craft’s future in ferrying cargo as well as passengers.

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