Posts Tagged ‘ancient’

Nubia, irrigation and parasitic worms, a tale told by a Mummy

// June 8th, 2011 // Comments Off on Nubia, irrigation and parasitic worms, a tale told by a Mummy // Recent Research

A few months ago I wrote about Ancient Nubians and their antibiotic beer, delivering a dose of tetracycline in every brew.

Now bioarcheologist George Armelagos has co-authored a study showing that early irrigation channels changed how humans were affected by parasites.

I’ll describe the research at the end, but first – a story! Make yourself a cup of tea and come back to read it.

Nubia, 500AD

Cotton. Image by Martin LaBar

Since he’d taken his first wobbly steps on Nubian soil, Alara had been pulling his then insubstantial weight on the family farm. He’d pull up weeds with grubby fingers under the watchful eye of his older cousins by day. Lunch was often a paltry loaf of flat bread to share between the lot of them, supplemented with whatever local edible plant was in season, eaten hastily and followed by a brief break in which he built dirt pyramids with other children.

Now 30, Alara remembered his childhood as carefree and unplanned. His memories swam together like waves billowed out from boats on the Nile. Only small moments stood out with any clarity. A snarling dog snapping at his leg. The taste of bread warmed by the sun, seasoned with hunger. Buzzing with disbelief at the stories told by his cousins of things adult and forbidden.

A life in the sun had baked him hard and capable, and he still worked on the same farm he had as a toddler. His extended family shared the plot of land, shared the work, shared the harvest, shared the income. Shared the good years and the bad. He was a cotton farmer through and through, born and raised to the plough.

A friendly slap on the should shook Alara out of his reverie. “Wake up, brother, you are asleep on your feet! It’s time for lunch and then I need to walk to the river and check the channels. The water is not flowing as it should. Will you go with me?”

“Lunch already, Arty? I didn’t notice the sun was so high. Of course I’ll come with you.”

The midday meal of onion and lentils served with flat bread for eating with was waiting hot on the table. They ate quickly and had a weak cup of tea before walking to the Nile.

They could hear the river well before they could see it. The sound of saqiya irrigation was like music that infiltrated the whole valley, though they were so used to it they barely heard it. As they approached their saqiya, they called out a greeting to Nala who was driving the cow.

“Nala! We have brought food for you.”

“Thank you uncle,” she called back. “I’ll come down to eat.”

Al-Jazari's Water-raising-device ca 1205AD

The saqiya was the heart of the farm, pumping the water of life from the river to the fields where it was needed. Made of wood, it consisted of cogs and a large open-spoked wheel. The cow, encouraged by young Nala, moved a wooden arm around, turning the wheels and cogs to move a pulley.

That pulley was studded with jars which dipped down into the water and lifted up to the farm’s main channel. Each jar then deposited its precious load which ran to the farm and branched out into smaller channels, delivering water for the cotton.

Alara inspected the cow and saqiya while Nala ate lunch. Despite a slightly thirsty cow, everything seemed to be working fine. The problem must lie in one of the channels.

Walking along the main channel, he stopped now and then to check the water level. Sometimes silt and aquatic plants collected at the bottom, blocking the flow of water. When he and Arty came to the first branch in the channel, they separated to cover more ground. Following his channel through several other branches, Alara found one that was a problem.

The side of the channel must have collapsed recently. Mud clogged the small stream, causing water to dam up behind it and overflow. Alara reached in and started to pull up clumps of the stuff. The water became turbulent and muddy, and he noticed more than a few of the fresh-water snails that liked to live in the slowly flowing channels. As he cleared it, the water began to run clean again and move into the farm. He spent the rest of the afternoon checking other channels, clearing several that were silting badly.

Though he didn’t know it, those snails were responsible for the troubling, itchy spots many adults had on their arms and feet. Well, it wasn’t the snails exactly, it was the tiny worms inside them.

Several species of trematode of the genus Schistosoma could infect humans. These tiny parasitic worms hatched in water and quickly found snails to infect, burrowing into their large feet. They moved through the life stages of miracidia and sporocyst inside that host, emerging as free swimming cercariae which needed a mammal host to continue to the next stages.

In contact with humans, or for some species other animals, they penetrated the skin and lost their tails, moving through the circulation as schistosomulae. In the liver they would mature into adults, pair, and migrate so the eggs they produced would be shed in stool. Those eggs would make their way to water to repeat the cycle.

Two weeks later, Alara woke in the night with a pain in his stomach which sent him running to the toilet area. By morning he was exhausted and feverish. Though the disease didn’t kill him, researchers would later find evidence of the parasitic worms in his mumified remains.

The research

Schistosomiasis, the chronic disease caused by these worms, is thought “the most important water-based disease from a global public-health perspective” in modern populations. It infects an estimated 200 million people per year. It has a low mortality rate, but causes development problems in children and damages internal organs.

Modern irrigation systems, particularly slow moving ones, boost the disease by providing habitats to the snails. But what about ancient populations?

To find out, Armelagos, Hibbs, Secor and Van Gerven studied dessicated remains (aka mummies) from two Nubian populations. Wadi Halfa (N = 46) lived in 500AD when the Nile was lower, and used saqiya irrigation on their crops. Kulubnarti (N = 191) lived 300 years later, during a time when Nile flooding was good and irrigation was less critical. They hypothesised the Wadi Halfa population would have more Schistosoma mansoni, and it would be more prevalent in children and men due to differential water contact.

One out of three ain’t bad. Indeed, Wadi Halfa people had more of the parastic worms: 26% to Kulubnarti’s 9%. However peak prevalence of infection did not occur at a younger age in the Wadi Halfa, and there was no sex difference.

ResearchBlogging.orgHibbs AC, Secor WE, Van Gerven D, & Armelagos G (2011). Irrigation and infection: The immunoepidemiology of schistosomiasis in ancient Nubia. American journal of physical anthropology, 145 (2), 290-8 PMID: 21469072

Note: I tried to be accurate about life in Nubia, 500AD, but please correct me in the comments

(Also, I want to be a bioarcheologist! Should I apply for one of these Graduate Programs at Emory University?

Connecting via common ancestors and Genographics – Interview with Wolfgang Haak

// December 8th, 2010 // Comments Off on Connecting via common ancestors and Genographics – Interview with Wolfgang Haak // Recent Research, Science Communication

At the Genographic Event at the RiAus I also interviewed Dr Wolfgang Haak, who spoke about Y-chromosome markers to determine paternal ancestry. He’s been involved in the Genographic Project for three and a half years.

What are the benefits of understanding ancestry?

It’s pretty much a personal thing, at the end of the day, because I suppose everyone’s interested in his or her own genetic history. This is my personal driving force, finding out more about myself. Where’s my place in this planet, in this world, where do I tie into the global picture? That’s a big motivation for me, and as I find out more as I work with people that it’s the same motor or driving force with them as well.

We share a common ancestry after all, there’s a common interest in our genetic history as well.

What first attracted you to the Genographic Project?

I have always been interested in genetics, but I actually come from an anthropologic background and genetics is certainly a part of that. I also come from an Ancient DNA lab. This was a step further into more modern population genetics. This is about getting both things together. Having a modern day perspective, plus adding a timely depth to that picture that we get from modern day diversity.

Tell us about your own ancestry, have you genotyped yourself?

Yes, I’ve done both. Mitochondrial, I’m haplogroup H, and I can further pin that down to group H1, so that is a Palaeolithic, Mesolithic one that might have come into Europe prior to the last glacial maximum, around modern day Spain or Italy or even a South Eastern refuge. It’s not entirely clear but we’ll find out over the next couple of years.

On the paternal side its even more enigmatic. I’m part of a North African lineage that probably originated around the Horn of Africa, so there’s that connection on the Eastern side of Africa where it connects to Saudi Arabia, and that has a high frequency there into the Nile Valley, and from it spreads into South Eastern Europe. Not entirely sure when it spread across the Mediterranean region, but probably historic times rather than prehistoric times.

Genographics, Neanderthals and Cannibalism, an Interview with Carles Lalueza-Fox

// December 8th, 2010 // 1 Comment » // Recent Research, Science Communication, Sex and Reproduction

After the event last night about the worldwide Genographic Project, I caught up with Prof Dr Carles Lalueza‑Fox, the first speaker on the night, for a quick interview. He’s an expert on Neanderthals, or Neandertals I think we call them now. Named after the Neander Valley where the first specimen was discovered.

What first sparked your interest in studying Neandertals?

When the first Neandertal sequence was retrieved in 1997 I had been working on ancient DNA for a while, but then Neandertals seemed to be something in a different league.

In the first ten years it was only possible to get mitochondrial DNA from Neandertals.

For me, I really liked Neandertals and human evolution as a child. Ancient DNA was something particularly difficult at the time, and the thing that brought me to the subject.

How human do you think Neandertals were?

How human?

Yes, tricky question.

Haha, yes. It’s a very long question, a very difficult question. One must always take into mind our tendencies are always fluctuating. We saw them as a very primitive human lineage in the early 20th Century, but I’d say that now we’re turning to the point where we see them as very similar to us.

Maybe the best thing to think about Neandertals is they are more different from us than any modern human to any other modern human. That’s the way we should think about them.

If we want to think of them as a different species that’s fine for me, but there is a range of difference between us and the Neandertals.

The cuts found along Neandertal bones you suggest are evidence for cannibalism. Could they just be an example of de-fleshing prior to burial?

Well, yeah, it might be right in some circumstances. But this is not only cutting, you know de-fleshing the bones. It’s also fragmenting the bones with small stone tools, very small fragments, and even the skull, and the faces. For me it’s very difficult to think that this kind of post mortem activity is something more because this is a complete destruction of the bones.

It’s very similar to what we see in other sites with fauna, the bones are broken to extract the marrow in the same way.

And it’s a pretty common thing, well, not common these days, but certainly we humans have our own history of cannibalism.

Yes, well there are several sites with the signs in Neandertals. But you almost think that life was very tough and they were structured in very small groups, so the fact that you find another one… I mean you’d say “hey, we are Neandertals all of us,” but I’d say that’s a modern conception.

Whereas for them it might be “hey, you’re not one of my family I may as well eat you.”

Yeah, the idea of humankind, in fact, is very recent. After the second World War, and the UNESCO thing. So even the idea of humankind is more recent than we might think now.

And what do you think of the possibility of Neandertals and humans mating?

I think it’s plausible with the data we have. It was probably something that was a minority, restricted in time and space, it was nothing important in my view. The thing is we can detect it now in non-African modern humans is because this was an expanding population, so even a small event of just a few, say it was, this was amplified later on.

Antibiotic beer, as drunk by the ancient Nubians

// September 8th, 2010 // 4 Comments » // Drugs, Recent Research

Image by Peter Trimming

Today’s schooner of science is literally science in a schooner. Plus it comes with a new career path – bioarcheologist, expert in ancient diets.

George Armelagos is the bioarcheologist in question, and he’d been studying the ancient Nubians who lived just south of ancient Egypt in present-day Sudan.

George was looking at some bones and found evidence that they had been exposed to tetracycline, an antibiotic. Tetracycline is absorbed into bone, and fluoresces green. It’s sometimes used to measure bone growth – take tetracycline at day 0, again at day 12, and at day 21 take a biopsy. The distance between the two green lines will show how far the bone grew in 12 days.

Anyhoo, tetracycline in bones from 350-550 AD is weird, seeing as we first invented antibiotics with the discovery of penicillin in 1928. Now we find out the ancient Nubians beat us to it, and as with all great ideas they came up with it over a beer.

The grain they used to ferment the beer contained streptomyces bacteria, which produces tetracycline as a kind of germ warfare. Like penicillin comes from a fungus, tetracycline is made by a bacteria. It’s a bad-ass antibacterial that can treat disease like chlamydia, gonorrhea, and pneumonia which are caused by bacteria. It can even kill Yersinia pestis cause of the black plague.

Were the ancient Nubians drinking it by accidental contamination, intentional medication, or did streptomyces bacteria just grew on the corpses?

To find out they needed (da dada dum!) a CHEMIST! This particular hero was Mark Nelson, who dissolved the bones in some hardcore hydrogen fluoride – “the most dangerous acid on the planet,” according to Mark. Woah. After showing the bones who was boss, Mark mass spec’d the shizz out of them and discovered a metric buttload of tetracycline, confirming that it was ingested and in high quantities.

The scientist duo concluded that this was a brew with a purpose – an antibiotic alcoholic. Even the bones from a four year old child contained a lot of tetracycline, perhaps he was given the antibacterial to cure a disease.

My question is, why are WE not taking our antibiotics in beer? That would be SO much better!

ResearchBlogging.orgNelson ML, Dinardo A, Hochberg J, & Armelagos GJ (2010). Brief communication: Mass spectroscopic characterization of tetracycline in the skeletal remains of an ancient population from Sudanese Nubia 350-550 CE. American journal of physical anthropology, 143 (1), 151-4 PMID: 20564518

Leviathan, the ancient marine predator discovered

// July 6th, 2010 // 1 Comment » // Recent Research, The Realm of Bizzare

Deep in a desert in Peru palaeontologists were searching for a skull. Some years ago, teeth thought to belong to a new species of marine animal had been found, but they needed a head to identify it. Hunting in the richest area for ancient sea remains, luck eluded them until the very last day of their travel. Then they found…

Leviathan melvillei. Named after that most fearsome animal the white whale, likened to Leviathan in Herman Melville’s most excellent book Moby Dick. In the old Testament Leviathan was a sea demon, a guardian of the gates of hell. Other cultures thought a dragon or a crocodile, but in modern Hebrew the word means simply whale.

And what a whale is Leviathan.

With 30 cm long teeth it was a dangerous predator. It may have hunted medium-sized baleen whales, who have no teeth and live on plankton. It’s huge teeth would have inflicted deep bites, tearing the baleen whales into pieces. Leviathan lived some 12 million years ago, and looks similar to a modern day sperm whale.

One major difference between the fossil and modern sperm whales is Leviathan had teeth on both jaws. Modern sperm whales only have teeth on the lower jaw, and eat by sucking squid into their mouth. Killer whales are like the funsize version of Leviathan, with teeth on both jaws and violence towards seals. Watch the YouTube documentary to find out more.

They haven’t found the rest of the fossil, so they don’t know how large the whale was, but it was probably around the same size as the sperm whales of today. That’s really big! The largest animal that has ever lived is the blue whale that is still in the ocean now. There are theories that the blue whale is as big as things will ever get.

And so let us take a moment to think of mighty, mad Ahab. That crazy captain who lost his leg to a sperm whale. Wherever you are, Ahab, I be glad you never lived to see this day. The mighty Moby Dick who stole your sanity had but half the dental framework of legendary Leviathan.

Paper published in Nature. Hat tip to Not Exactly Rocket Science.

Update: The name Leviathan was already taken (whoops!) so it has now been renamed Livyatan melvillei, Livyatan being a Hebrew name for large marine monsters.






Buy me a Beer!
    If you don't want me to mention your donation just check the box above.
  • $ 0.00
Twittarrr
Follow @CaptainSkellett (560 followers)