Friday, August 4, 2017

The Anthropology of Alzheimers

Anthropologists are not often in the news, and they are even more rarely in the spotlight for discovering what might be a connection between a human ill and how other people live. But anthropologist Ben Trumble was recently profiled (or his work was) in The New York Times for suggesting that Alzheimer's is so common in Western culture because we are devoid of regular parasitic infection.



Trumble's work comes from a long-term and collaborative study of the Tsimane of Bolivia. The Tsimane live in savannas and forests and they make a living by growing things to eat, foraging and hunting. Although many South American cultures have been affected by missionary or governmental zeal to acculturate them into Western ways, the Tsimane have resisted and maintain their identity and way of life.


Along line of Western researchers have spent time with the Tsimane since 2001 and their main focus has been their health and welfare over the human life cycle. Trumble focuses and contrary to what Westerners might expect, once successfully past childhood, many Tsimane live into their 90s and they are physically very healthy. Tumble became especially interested in the possible role of Alzheimer's and dementia in their lives.

Tumble put together what is currently known about the genetics and biology of Alzheimers with the particular life circumstances of the Tsimane and came up with the possibility that being subject to repeated parasitic infections repeatedly might have a key to understanding why some people exhibit Alzheimers and others do not.

Working with the Tsimane, Trumble compared the incidence of the ApoE4 gene, which in a double blast increases the risk of Alzheimers tenfold in the West, to results of cognitive tests with his volunteers. He found that Tsimane elderly who had a copy of the gene in fact did better on those tests than those with no ApoE4.

But that's not the really surprising part. Trumble also compared these results, genetic and cognitive, with parasite load. It seems that those with the gene in single or double form and parasites retained their mental acuity while those without parasites and even one copy of ApoE4 often did not.  They looked like Westerners in terms of cognitive ability.

In other words, what we now see as a "bad" gene might have been protective and "good" when our ancestors lived a less parasitic life. Those genes might have evolved to protect our aging brains from parasites and now they are, instead, damaging brain cells because their evolutionary environment has changed.

Friday, July 21, 2017

Take a Little Walk With Me





One of the most amazing things humans have ever done is walk around the world.



I don't mean one of those adventures where someone walks from Maine to Florida to lose weight, or California to New York just to prove they can. No, I mean that humans, as a species, have walked and walked and walked across the globe.

This desire to keep going must have very ancient roots for us. Early humans evolved in Africa, but about 1.5 millions years ago a species we now call Homo erectus walked out of Africa and headed east. They ended up in China and Indonesia and probably lots of other places we haven't discovered yet.

Image result for Homo erectus walkingThat first wave of world walkers was then followed, again and again, by various early humans and eventually by what we think of as fully modern humans or Homo sapiens sapiens.

And those people traveled even further, all the way to Australia, populating the Pacific Islands as they went. They were helped by land masses that have since been covered over by the Pacific and other bodies of water. But still, that's a long way to go to settle down.

Anthropologists have not been very sure about the exact dates of that exodus, but this week, Australian archaeologists confirmed that modern humans reach Australia by 65, 000 year ago.

Preserved campfires, mortars and pestles, stone tools and painting materials confirm that modern humans, who evolved about 200,000-300,000 years ago in Africa, reached Australia pretty quickly and they kept to themselves and became the aboriginal people of today.

In fact, some of the researchers on the archaeology team were aborigines, a telling connection to the artifacts they were discovering.

This new archaeological work confirms recent DNA research published earlier this year that showed a date of 50,000 year ago for the ancestral aboriginal population.

But why did anyone leave Africa? And when they left, why in the world did they go so far?



We are not talking about a road trip that covered miles in hours, but an expedition that spanned continents in tens of thousands of years. One can only guess that they were following food (as in animals that walk around) or looking for food (as in vegetable matter during a drought), or maybe running away from something. But what? Over and over? We wait to hear more.

And by the way, Australia a young nation? Yea, no. Not at all.



Wednesday, July 5, 2017

The Plague Is Back




As the New Mexico Department of Heath recently reported, the plague is still with us. Three people in New Mexico have become ill with symptoms of plague this year, which means flu-like symptoms and some add ons, and they were treated and released from the hospital. But one person in New Mexico has died from the plague in recent years.

There are, it seems, three kinds of plague—pneumonic includes dangerous pneumonia, septicemic p makes the skin and other body parts turn black, and bubonic which causes swelling of the lymph nodes into baseballs. In other words, plague is not just a generic terms for any disease that spreads rapidly and potentially kills millions.  Plagues is, instead, a particular bacteria called Yersinia pestis. 

What makes plague different from other contagious disease is the rapidity of its spread and the high risk of fatality if not treated.

We can blame rodents, and the fleas that bite them, for spreading plague to people, but who we really should blame is ourselves. Plague, and any infections disease, is a disease of civilization. That is, these scourges can spread because humans like to live in big groups and those groups are just the host that Yersinia pestis  thrives on.

Over the centuries, plague has devastated various populations and changed the history of the Middle ages and the Renaissance of Europe. But plague also initiated the cornerstone of public heath, and that happened in Venice, Italy.

In 1348, Venice was the first city that attempted to stop the spread of disease by making ships anchor off shore for 40 days (quaranta is Italian for 40, thus quarantine), and this was before anyone had a good idea how diseases spread. That quarantine was a sign of the strength of The Venetian Republic's desire to protect it citizens and its commerce which depended on ships coming and going.

Image result for Venetian republic

That same year Venice implemented a rule that anyone who died of plague had to be buried on remote islands far away from the city, suggesting they knew, or hypothesized, that one could get this disease even from a corpse.


 In 1423 Venice then built a permanent plague hospital on a lagoon island just offshore — Santa Maria di Nazareth — where victims and their families were deported at the first sign of plague. Eventually that place was called Lazaretto (after Lazarus, a hope that someone could rise from the dead, even from plague). Other cities then followed Venice's example.

Image result for plague hospital venice

And today we quarantine everything from people to plants as a standard public heath measure, the best, and easiest, just-in-case measure to protect large populations from each other.

Image result for plague venice


Monday, June 12, 2017

Baby Food

Image result for three month old eating a bone


 My daughter’s first solid food, at three months of age, was ossobuco, the Italian dish of meat, wine and vegetables. If we had been Italian, or even visiting Italy, this would have made sense. 

In fact, if she had been gumming her mashed up ossobuco in a restaurant in Italy the other diners would have ignored her, or clapped. 

Since then, she has gone through phases of liking or not liking particular foods, but this past weekend she texted me a photograph of herself eating jellyfish, and I thanked the ossobuco and the wide array of dishes that she’s been offered over nineteen years for her adventurous gastronomic spirit. 

But apparently, loading her baby spoon with food from other cultures is not all that was going on at our table. In a series of experiments with over 200 one-year-olds, Development Psychologists Zoe Liberman and Kathern Kinzler of Cornell University watched babies as the babies watched films of adults eating. This research protocol is a walk in the park because babies are fascinated with other people and when they gaze at someone for a long time, it’s meaningful. In general, the babies paid little attention if one person liked a food and the next person did as well but they stared longer, presumably confused, when the subsequent diner was disgusted by the test food. 


More important, the babies also made layered social distinctions. If the two diners acted like friends and spoke the same language the babies expected them to like the same things. If they acted like enemies or spoke different languages, the babies expected different reactions to food.



We know that what we eat is highly cultural. Just discuss cupcakes and orange soda with the Maasai and watch them make the yuk face while we, in Western culture, would be hard pressed to drink a cocktail of milk and blood. Every culture’s diet is based on a particular kind of subsistence pattern linked to such mundane things as climate, topography, and available raw materials. The recent study shows that babies are not just being indoctrinated into their own cultures by the foods they are offered. They are also innately clocking people who look or talk the same or different, noting enemies and friends, figuring out who to trust and who not to trust. In other words, eating with others is one way babies go about filling in their social map. And eating alone is lonely.





As such, food is not just a cultural moment or a window to the past, it is not just identity or nutrition. Food and what we like or dislike is also one of the threads of connection that signal someone is one of us or not, a point of social communication that even infants recognize.

If I had known all this nineteen years ago, I might have paid more attention to the the context of my daughter’s first real meal. I would have seen her taking note of the reactions by the people at the table, good friends and devoted foodies who loved ossobuo. Her growing baby brain, already geared to such calculations, would have surely digested the fact that these people were part our tribe and that she was culturally home.

Thursday, May 25, 2017

The Monkey in the Coal Mine

A recent outbreak of yellow fever in Brazil has resulted in at least 240 human deaths and over 4,400 monkey deaths. The outbreak has also had a secondary fatal effect on the monkeys—people are capturing and killing monkeys or clubbing and stoning them to death thinking the moneys must somehow be at fault. 
Image result for howler monkeys
In fact, the monkeys have nothing to do with it, and authorities are now begging citizens to stop killing them. 

Yellow fever is transmitted by mosquitoes, not mammals, and certainly not monkeys. As the death toll shows, these animals, fellow primates, are just as vulnerable to yellow fever as humans, maybe more so. 

And of course, the fault is really ours. Slash and burn agriculture, deforestation, and climate change have made swamp out of large swaths of tropical forest. Swamps where where mosquitoes thrive. The human touch, fueled globally by greed, is turning a once pristine ecosystem into a charnel house. 

Image result for brazilian monkeys
In that scenario, monkeys are actually useful and shouldn't be bludgeoned to death because they can be harbingers of infectious disease. (This sort of explanation, pointing out how some animal should be saved because it's useful to humans, pisses me off. But then I don't think humans are in charge of everything and every creature.) 

That is, Brazilian authorities point out, the monkeys are the tropical equivalent of  "canaries in the coal mine." Miners used to bring caged canaries into the mines and when a canary died, they knew it was time to get out of that hole as soon as possible. 

Danilao Simonini Teixeira, the president of the Brazilian Society of Primatology says  that people living in areas gripped with yellow fever don't seem to understand that monkeys are crucial to signaling the onset and march of diseases. Monkeys and humans are closely related primates and so when monkeys start dying it means something bad for humans. 

Also, monkey deaths from yellow fever are putting some species, such as the golden lion tamarin at risk of extinction.   

Image result for brazilian monkeys
Brazil has has the greatest diversity of primate species on earth and what a shame to loose any of it at the direct hand of humans, as if the human caused habitat destruction  weren't enough. 

When we are scared, we pick on the vulnerable, even when it wasn't their fault, even when they had absolutely nothing to do with it, even if they are suffering as well. 
Image result for brazilian monkeys

And even when those vulnerable are so incredibly beautiful.










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The Anthropology of Alzheimers

Anthropologists are not often in the news, and they are even more rarely in the spotlight for discovering what might be a connection between...