Category: Africa

Even With Quick Cheap Malaria Lab Tests, Dog Noses Can Still “Be Very Useful”

(p. D4) A small pilot study has shown that dogs can accurately identify socks worn overnight by children infected with malaria parasites — even when the children had cases so mild that they were not feverish.

The study, a collaboration between British and Gambian scientists and the British charity Medical Detection Dogs, was released last week at the annual convention of the American Society of Tropical Medicine and Hygiene.

. . .

The new study, its authors said, does not mean that dogs will replace laboratories. Inexpensive rapid tests for malaria have been available for over a decade; more than 200 million people in dozens of countries are infected each year.

But for sorting through crowds, malaria-sniffing dogs could potentially be very useful.

Some countries and regions that have eliminated the disease share heavily trafficked borders with others that have not. For example, South Africa, Sri Lanka and the island of Zanzibar have no cases but get streams of visitors from Mozambique, India and mainland Tanzania.

And when a region is close to eliminating malaria, dogs could sweep through villages, nosing out silent carriers — people who are not ill but have parasites in their blood that mosquitoes could pass on to others.

. . .

If just one chemical indicated cancer or malaria, “we’d have discovered it by now,” said Claire Guest, who founded Medical Detection Dogs in 2008 and oversaw dog training in the study. “It’s more like a tune of many notes, and the dogs can pick it up.”

For the full commentary see:

Donald G. McNeil Jr. “Global Health; Sniffing Out Malaria in Its Tracks.” The New York Times (Tuesday, November 6, 2018 [sic]): D4.

(Note: ellipses added.)

(Note: the online version of the commentary has the date Nov. 5, 2018 [sic], and has the title “Global Health; Dogs Can Detect Malaria. How Useful Is That?”)

A later-published version of the initial “small pilot study” discussed above is:

Guest, Claire, Margaret Pinder, Mark Doggett, Chelci Squires, Muna Affara, Balla Kandeh, Sarah Dewhirst, Steven V. Morant, Umberto D’Alessandro, James G. Logan, and Steve W. Lindsay. “Trained Dogs Identify People with Malaria Parasites by Their Odour.” The Lancet Infectious Diseases 19, no. 6 (June 2019): 578-80.

Human Ancestor 1.45-Million Years Ago Was a Victim of Cannibalism

Modern capitalism is sometimes criticized as inferior to a long-ago golden age. A past golden age is a myth. Human ancestors suffered from cannibalism and other violence.

(p. D3) In today’s scholar-eat-scholar world of paleoanthropology, claims of cannibalism are held to exacting standards of evidence. Which is why more than a few eyebrows were raised earlier this week over a study in Scientific Reports asserting that a 1.45-million-year-old fragment of shin bone — found 53 years ago in northern Kenya, and sparsely documented — was an indication that our human ancestors not only butchered their own kind, but were probably, as an accompanying news release put it, “chowing down” on them, too.

The news release described the finding as the “oldest decisive evidence” of such behavior. “The information we have tells us that hominids were likely eating other hominids at least 1.45 million years ago,” Briana Pobiner, a paleoanthropologist at the Smithsonian’s National Museum of Natural History and first author of the paper, said in the news release.

. . .

Dr. Pobiner, an authority on cut marks, had spied the half-tibia fossil six summers ago while examining hominid bones housed in a Nairobi museum vault. She was inspecting the fossil for bite marks when she noticed 11 thin slashes, all angled in the same direction and clustered around a spot where a calf muscle would have attached to the bone — the meatiest chunk of the lower leg, Dr. Pobiner said in an interview.

She sent molds of the scars to Michael Pante, a paleoanthropologist at Colorado State University and an author on the study, who made 3-D scans and compared the shape of the incisions with a database of 898 tooth, trample and butchery marks. The analysis indicated that nine of the markings were consistent with the kind of damage made by stone tools. Dr. Pobiner said that the placement and orientation of the cuts implied that flesh had been stripped from the bone. From those observations she extrapolated her cannibalism thesis.

“From what we can tell, this hominin leg bone is being treated like other animals, which we presume are being eaten based on lots of butchery marks on them,” Dr. Pobiner said. “It makes the most sense to presume that this butchery was also done for the purpose of eating.”

. . .

. . ., clear proof of systematic cannibalism among hominids has emerged in the fossil record. The earliest confirmation was uncovered in 1994 in the Gran Dolina cave site of Spain’s Atapuerca Mountains. The remains of 11 individuals who lived some 800,000 years ago displayed distinctive signs of having been eaten, with bones displaying cuts, fractures where they had been cracked open to expose the marrow and human tooth marks.

Among our other evolutionary cousins now confirmed to have practiced cannibalism are Neanderthals, with whom humans overlapped, and mated, for thousands of years. A study published in 2016 reported that Neanderthal bones found in a cave in Goyet, Belgium, and dated to roughly 40,000 B.C. show signs of being butchered, split and used to sharpen the edges of stone tools. Patterns of bone-breakage in Homo antecessor, considered the last common ancestor of Neanderthals and Homo sapiens, suggest that cannibalism goes back a half-million years or more.

For the full story see:

Franz Lidz. “For Paleoanthropology, Cannibalism Can Be Clickbait.” The New York Times (Tuesday, June 11, 2024): D3.

(Note: ellipses added.)

(Note: the online version of the story was updated July 3, 2023, and has the title “Cannibalism, or ‘Clickbait’ for Paleoanthropology?”)

The study in Scientific Reports mentioned above is:

Pobiner, Briana, Michael Pante, and Trevor Keevil. “Early Pleistocene Cut Marked Hominin Fossil from Koobi Fora, Kenya.” Scientific Reports 13, no. 1 (2023): 9896.

Humans’ Adaptive, Flexible Intelligence Evolved Where Climate “Change Was Dramatic, Frequent, Unpredictable and Stressful”

(p. C9) In “Origins: How Earth’s History Shaped Human History,” astrobiologist and professor of science communication Lewis Dartnell argues that “there is a clear causal chain taking us from the politics and socio-economic conditions of today, to their roots in historical agricultural systems, and then further back to the geological tapestry of the ground beneath our feet.”

. . .

The final sentence he offers as summation—“The Earth made us”—can be read two ways, capturing the parallel themes of “Origins.”

With emphasis on “us,” it refers to the origin of the genus Homo, a clade of naked apes giving rise to our species, H. sapiens, the greatest biological superpower of all time, one so potent that all others in our genus are extinct. Why did this emergence take place in the cradle of the East African Rift and nowhere else? And why did the arrival of our genus broadly coincide with the onset of high-frequency climatic swings about two million years ago? Mr. Dartnell concludes that this recently uplifted and intricately rifted landscape created a mosaic of habitats dominated by lakes that further amplified the climatic oscillations between dry-wet and hot-cool conditions. Change was dramatic, frequent, unpredictable and stressful. Thus “intelligence” became “the evolutionary solution to the problem of an environment that shifts faster than natural selection can adapt the body . . . driving . . . ever more flexible and intelligent behavior.”

For the full review, see:

Robert M. Thorson. “The Earth and Us.” The Wall Street Journal (Saturday, April 23, 2022 [sic]): C9.

(Note: ellipsis between paragraph, added; ellipses within paragraph, in original.)

(Note: the online version of the review has the date May 9, 2019 [sic], and has the title “‘Origins’ Review: The Earth and Us.”)

The book under review is:

Dartnell, Lewis. Origins: How Earth’s History Shaped Human History. New York: Basic Books, 2019.

Small-Brained Early Humans Buried Their Dead and Used Symbols

(p. A16) Discoveries from a subterranean cave system in South Africa are prompting paleoanthropologists to rethink what makes us human. New findings reveal a small-brained human relative known as Homo naledi buried its dead and carved symbols on walls inside the system. Both these behaviors were previously associated with our species or the big-brained Neanderthals with which we interbred.

“We’re looking at cultural behavior that is very human in a species that has a brain a third the size of ours,” said John Hawks, a University of Wisconsin-Madison paleoanthropologist and co-author of the research released Monday [June 5, 2023], which will soon be published in the journal eLife as reviewed preprints. “It is going against the idea that brain size is what made us human.”

. . .

“We’ve never had a creature that manifested the complexity of us that wasn’t us,” said Lee Berger, a paleoanthropologist and an explorer in residence at National Geographic who co-authored the new research. Homo naledi, he added, is “threatening to the very clearly defined narrative of the rise of human exceptionalism.”

For the full story, see:

Aylin Woodward. “Ape-Size-Brained Relative Upends Theories.” The Wall Street Journal (Tuesday, June 6, 2023): A16.

(Note: ellipsis, and bracketed date, added.)

(Note: the online version of the story was updated June 5, 2023, and has the title “New Homo Naledi Cave Discoveries Upend What We Know About Being Human.”)

The reference to the journal preprint mentioned above is:

Agustin, Fuentes, Kissel Marc, Spikins Penny, Molopyane Keneiloe, Hawks John, and R. Berger Lee. “Burials and Engravings in a Small-Brained Hominin, Homo Naledi, from the Late Pleistocene: Contexts and Evolutionary Implications.” bioRxiv (2023): 2023.06.01.543135.

Homo Sapiens’s Greater Genetic Diversity May Have Allowed Them to Adapt to Climate Change Faster than Neanderthals

(p. D5) Scientists have revealed a surprisingly complex origin of our species, rejecting the long-held argument that modern humans arose from one place in Africa during one period in time.

By analyzing the genomes of 290 living people, researchers concluded that modern humans descended from at least two populations that coexisted in Africa for a million years before merging in several independent events across the continent. The findings were published on Wednesday [May 24, 2023} in Nature.

“There is no single birthplace,” said Eleanor Scerri, an evolutionary archaeologist at the Max Planck Institute for Geoarchaeology in Jena, Germany, who was not involved in the new study. “It really puts a nail in the coffin of that idea.”

. . .

The researchers concluded that as far back as a million years ago, the ancestors of our species existed in two distinct populations. Dr. Henn and her colleagues call them Stem1 and Stem2.

About 600,000 years ago, a small group of humans budded off from Stem1 and went on to become the Neanderthals. But Stem1 endured in Africa for hundreds of thousands of years after that, as did Stem2.

If Stem1 and Stem2 had been entirely separate from each other, they would have accumulated a large number of distinct mutations in their DNA. Instead, Dr. Henn and her colleagues found that they had remained only moderately different — about as distinct as living Europeans and West Africans are today. The scientists concluded that people had moved between Stem1 and Stem2, pairing off to have children and mixing their DNA.

. . .

It’s possible that climate upheavals forced Stem1 and Stem2 people into the same regions, leading them to merge into single groups. Some bands of hunter-gatherers may have had to retreat from the coast as sea levels rose, for example. Some regions of Africa became arid, potentially sending people in search of new homes.

Even after these mergers 120,000 years ago, people with solely Stem1 or solely Stem2 ancestry appear to have survived. The DNA of the Mende people showed that their ancestors had interbred with Stem2 people just 25,000 years ago. “It does suggest to me that Stem2 was somewhere around West Africa,” Dr. Henn said.

. . .

Dr. Scerri speculated that living in a network of mingling populations across Africa might have allowed modern humans to survive while Neanderthals became extinct. In that arrangement, our ancestors could hold onto more genetic diversity, which in turn might have helped them endure shifts in the climate, or even evolve new adaptations.

“This diversity at the root of our species may have been ultimately the key to our success,” Dr. Scerri said.

For the full story, see:

Carl Zimmer. “A Study’s New Twist on How the First Humans Evolved.” The New York Times (Tuesday, May 30, 2023): D5.

(Note: ellipses, and bracketed date, added.)

(Note: the online version of the story was updated May 24, 2023, and has the title “Study Offers New Twist in How the First Humans Evolved.”)

The article in Nature mentioned above is:

Ragsdale, Aaron P., Timothy D. Weaver, Elizabeth G. Atkinson, Eileen G. Hoal, Marlo Möller, Brenna M. Henn, and Simon Gravel. “A Weakly Structured Stem for Human Origins in Africa.” Nature 617, no. 7962 (May 25, 2023): 755-63.

Nimbly Resilient African Coffee Farmers Switch to Coffee Bean that Withstands Global Warming

(p. A1) First the bad news. The two types of coffee that most of us drink — Arabica and robusta — are at grave risk in the era of climate change.

Now the good news. Farmers in one of Africa’s biggest coffee exporting countries are growing a whole other variety that better withstands the heat, drought and disease supersized by global warming.

. . .

Catherine Kiwuka, a coffee specialist at the National Agricultural Research Organization, called Liberica excelsa “a neglected coffee species.” She is part of an experiment to introduce it to the world.

. . .

(p, A6) In 2016, she invited Aaron Davis, a coffee scientist from the Royal Botanical Gardens in Kew, England, to Zirobwe. He was skeptical at first. He had tasted Liberica elsewhere and found it to be like “vegetable soup,” he said.

But then, the next day, he ground the beans from Zirobwe in his hotel room. Yes, a coffee researcher always packs a portable grinder when traveling.

“Actually, this is not bad,” he recalled thinking. It had potential.

. . .

Dr. Kiwuka and Dr. Davis teamed up. They would encourage farmers to improve the harvesting and drying of their Liberica crop. Instead of tossing them in with the robusta beans, they would sell the Libericas separately. If they met certain standards, they would get a higher price.

“In a warming world, and in an era beset with supply chain disruption, Liberica coffee could re-emerge as a major crop plant,” they wrote in Nature, the scientific journal, this past December.

For the full story, see:

Somini Sengupta. “Hardier Brew: African Farmers Bet on Climate-Resistant Coffee.” The New York Times (Saturday, April 29, 2023): A1 & A6.

(Note: ellipses added.)

(Note: the online version of the story has the date April 28, 2023, and has the title “What Climate Change Could Mean for the Coffee You Drink.”)

The article in Nature Plants mentioned above is:

Davis, Aaron P., Catherine Kiwuka, Aisyah Faruk, Mweru J. Walubiri, and James Kalema. “The Re-Emergence of Liberica Coffee as a Major Crop Plant.” Nature Plants 8, no. 12 (Dec. 2022): 1322-28.

Small “Creative” Subsistence Farmers Experiment and Innovate to Adapt to Global Warming

(p. A1) When it comes to growing food, some of the smallest farmers in the world are becoming some of the most creative farmers in the world. Like Judith Harry and her neighbors, they are sowing pigeon peas to shade their soils from a hotter, more scorching sun. They are planting vetiver grass to keep floodwaters at bay.

They are resurrecting old crops, like finger millet and forgotten yams, and planting trees that naturally fertilize the soil. A few are turning away from one legacy of European colonialism, the practice of planting rows and rows of maize, or corn, and saturating the fields with chemical fertilizers.

“One crop might fail. Another crop might do well,” said Ms. Harry, who has abandoned her parents’ tradition of growing just maize and tobacco and added peanuts, sunflowers, and soy to her fields. “That might save your season.”

It’s not just Ms. Harry and her neighbors in Malawi, a largely agrarian nation of 19 million on the front lines of climate hazards. Their scrappy, throw-everything-at-the-wall array of innovations is multiplied by small subsistence farmers elsewhere in the world.

. . .

(p. A10) . . . Mr. Mponda, 26, grows maize. But he no longer counts on maize alone. The soil is degraded from decades of monoculture. The rains don’t come on time. This year, fertilizer didn’t either.

“We are forced to change,” Mr. Mponda said. “Just sticking to one crop isn’t beneficial.”

The total acreage devoted to maize in Mchinji District, in central Malawi, has declined by an estimated 12 percent this year, compared with last year, according to the local agricultural office, mainly because of a shortage of chemical fertilizers.

Mr. Mponda is part of a local group called the Farmer Field Business School that runs experiments on a tiny plot of land. On one ridge, they’ve sown two soy seedlings side by side. On the next, one. Some ridges they’ve treated with manure; others not. Two varieties of peanuts are being tested.

The goal: to see for themselves what works, what doesn’t.

For the full story, see:

Somini Sengupta. “Climate Shocks Force Small Farmers to Reinvent.” The New York Times (Friday, April 28, 2023): A1 & A10.

(Note: ellipses added.)

(Note: the online version of the story has the date April 27, 2023, and has the title “Meet the Climate Hackers of Malawi.”)


Poor People Benefit More From “Entrepreneurial Capitalism” Than From Philanthropy

(p. A15) Paul David Hewson said it best during a 2012 speech at Georgetown University. Wait, who? “Aid is just a stopgap,” said Mr. Hewson, whose stage name is Bono. “Commerce [and] entrepreneurial capitalism take more people out of poverty than aid. We need Africa to become an economic powerhouse.” We still haven’t found what he’s looking for. An economic powerhouse would be able to afford mosquito nets and malaria drugs without handouts. That should be the endgame.

. . .

At its best, lots of philanthropy is very useful, but may not be sustainable over time—a sugar high that rarely enables that “teach a man how to fish” thing. Effective altruism may be an oxymoron. And it’s hard to miss that much of philanthropy is to fix government failures in education, welfare or medicine. I think that was Bono’s point.

But at its shadiest, philanthropy drives the misallocation of capital, overvaluing professors, the U.N. and climate poets and undervaluing those who can productively increase societal wealth to fund solutions to the future’s harder problems.

If only there were a way to use capital to provide opportunity, train workers, pay middle-class wages, help people build wealth . . . wait, it just came to me. How about starting new companies and investing in entrepreneurs and world-changing technology?

For the full commentary, see:

Andy Kessler. “INSIDE VIEW; A Wrench Thrown Into Capitalism.” The Wall Street Journal (Monday, April 17, 2023): A15.

(Note: ellipsis between paragraphs, added; ellipsis internal to last quoted paragraph, in original; bracketed word in original.)

(Note: the online version of the commentary has the date April 16, 2023, and has the same title as the print version.)

In Poor Country Where “Few People Have Air Conditioning” Heat Reduces Ability of Children to Learn and Parents to Produce

A growing movement among intellectuals opposes economic growth. I doubt that the movement will catch on in Freetown, Sierra Leone, where economic growth would allow more citizens to afford air conditioning.

(p. A4) . . . Eugenia Kargbo . . . [is] Freetown’s first chief heat officer, a post created in 2021, . . .

. . .

“Heat is invisible but it’s killing people silently,” Ms. Kargbo said in an interview on one of the top floors of Freetown’s city hall, a massive air-conditioned building that towers over the dozens of informal settlements dotting the capital of the small West African nation.

“Children are not sleeping at night because of extreme temperature,” she said. “It affects their ability to learn and their parents’ productivity.”

. . .

The country is one of the world’s poorest; few people have air conditioning; . . .

For the full story, see:

Elian Peltier. “In West African Hub, She Works to Counter Rising Temperatures.” The New York Times (Tuesday, January 7, 2023): A4.

(Note: ellipses added.)

(Note: the online version of the story has the date January 6, 2023, and has the title “She Is Africa’s First Heat Officer. Can She Make Her City Livable?”)

Lethality of Ebola in West Africa Mainly Due to “the Contingent History of a Population Made Vulnerable”

(p. 22) As Farmer writes in his new book, “Fevers, Feuds, and Diamonds: Ebola and the Ravages of History,” by the time he arrived in the capital city of Freetown in late September, “western Sierra Leone was ground zero of the epidemic, and Upper West Africa was just about the worst place in the world to be critically ill or injured.”

. . .

Farmer notes that even severe cases of Ebola rarely produce the horror-film symptoms featured so prominently in Preston’s “Hot Zone”: patients bleeding from their eyeballs, their organs liquefied in a matter of hours. Most cases instead involve fluid and electrolyte loss caused by vomiting and diarrhea, which can often be treated with basic supportive and critical care, like intravenous fluid replenishment or dialysis. Ebola was so lethal in upper West Africa not because the virus itself conveyed an inevitable death sentence, but because countries like Liberia and Sierra Leone lacked these health care essentials. “For all their rainfall,” Farmer writes, “their citizens are stranded in the medical desert.”

. . .

“This was not,” Farmer writes, “a history of inevitable mortality that resulted from ancient evolutionary forces.  . . .   It was the contingent history of a population made vulnerable.”

For the full review, see:

Steven Johnson “A Preventable Epidemic.” The New York Times Book Review (Sunday, December 13, 2020): 22.

(Note: ellipses between paragraphs, added; ellipsis internal to last paragraph, in original.)

(Note: the online version of the review has the date Nov. 17, 2020, and has the title “The Deadliness of the 2014 Ebola Outbreak Was Not Inevitable.”)

The book under review is:

Farmer, Paul. Fevers, Feuds, and Diamonds: Ebola and the Ravages of History. New York: Farrar, Straus and Giroux, 2020.

Geophysical Science Is Not Settled

(p. D2) Last year, one of the most dangerous volcanoes in Africa erupted without warning.

. . .

Now, in a new study published this Wednesday [Aug. 31, 2022] in Nature, Delphine Smittarello, a geophysicist at the European Center for Geodynamics and Seismology in Walferdange, Luxembourg, and her colleagues articulated how the eruption managed to ambush everyone.

. . .

This sort of unannounced eruption offers scientists a harsh lesson: For every paradigm-shifting secret they extract from their mountainous subjects, “there are always things that we don’t understand,” said Emily Montgomery-Brown, a geophysicist at the U.S. Geological Survey’s Cascades Volcano Observatory who was not involved in the study. “It’s a good reminder not to get cocky.”

. . .

. . . it’s possible that we will never become perfect prophets of our volcanic futures. “There may be things we will never be able to forecast,” Dr. Montgomery-Brown said.

For the full story, see:

Robin George Andrews. “An Eruption That Forecasters Couldn’t Foresee.” The New York Times (Tuesday, September 6, 2022): D2.

(Note: ellipses, and bracketed date, added.)

(Note: the online version has the date Sept. 2, 2022, and has the title “A Volcano Erupted Without Warning. Now, Scientists Know Why.”)

The article in Nature mentioned above is:

Smittarello, D., B. Smets, J. Barrière, C. Michellier, A. Oth, T. Shreve, R. Grandin, N. Theys, H. Brenot, V. Cayol, P. Allard, C. Caudron, O. Chevrel, F. Darchambeau, P. de Buyl, L. Delhaye, D. Derauw, G. Ganci, H. Geirsson, E. Kamate Kaleghetso, J. Kambale Makundi, I. Kambale Nguomoja, C. Kasereka Mahinda, M. Kervyn, C. Kimanuka Ruriho, H. Le Mével, S. Molendijk, O. Namur, S. Poppe, M. Schmid, J. Subira, C. Wauthier, M. Yalire, N. d’Oreye, F. Kervyn, and A. Syavulisembo Muhindo. “Precursor-Free Eruption Triggered by Edifice Rupture at Nyiragongo Volcano.” Nature 609, no. 7925 (Sept. 1, 2022): 83-88.

(Note: the Sept. 1 issue of Nature was “published” on Aug. 31.)