As predicted by me in my post earlier today, a pair (ha!) of magnitude 5+ earthquakes hit off the Sandwich Islands (ha?) today. One happened at 08:46:32 UTC (before I posted, but I didn’t know at the time) and another, slightly stronger, at 17:04:50 UT.

There was a bigger one — magnitude 6.5 — off the coast of Taiwan, but that was much earlier today, actually yesterday evening US time, so I don’t count that one. But who knows? The day’s not over yet.

Everything is connected. And when I say everything, I include you, dear reader, and the tapeworms of Madagascar. They carry a hidden history of our entire species.

I’m sure we’d all prefer that there was no such connection. Tapeworm are not just gross, but they are pretty much the polar opposite of the human existence. They have no brain. They have no eyes. They lack mouths and guts, having turned their body inside out, absorbing food through its surface. Most of their hideously long body is made up of segments, each of which contains its own supply of both eggs and sperm. To reproduce, the tapeworm fertilizes its eggs, either with its own sperm or another tapeworm’s, and then sheds its segments. Once out of the body, those segments can crawl around on the ground on their own.

But, like it or not, tapeworms–or at least the pork tapeworm Taenia solium–has an intimate relationship with us. After all, it can only live in our guts as an adult, where it will dwell for years and grow over 20 feet long. Without us, these tapeworms would simply not exist. From the safety of our guts, they can shed six egg-loaded segments a day, each of which contains 50,000 eggs. If a pig swallows one of these eggs, it hatches in the animal’s instestines, drills its way into the abdominal cavity, and finds a muscle to infect. There it dwells in a barely visible cyst, for years if need be. In order to complete its life cycle, it must get into another human, which it does if a human eats a piece of infected, undercooked pork.

Carrying an adult tapeworm around in your gut may be disturbing, but it’s not the worst thing a tapeworm can do to you. Sometimes people get infected with the eggs of pork tapeworms, rather than the cysts. Instead of developing into an adult, the tapeworm treats you like a pig. It invades your muscles, where it makes a cyst. Sometimes the tapeworms can get into people’s brains. These cysts can trigger dangerous reactions from our immune systems, and can sometimes be fatal. This disease, known as cysticercosis, is relatively rare in the United States. Only 221 people died of it between 1990 and 2002. But in other parts of the world, it’s a lot worse, with ten percent or so of the population of many countries showing signs of having had the disease.

Madagascar is one of those countries. In the highlands, over 20% of people have antibodies to cysticercosis. To get a better handle on the epidemiology of the disease, medical researchers at the Pasteur Institute of Madagascar have traveled around the country, gathering tapeworm from different regions. They isolated DNA from 13 of the samples and then compared their genetic sequences to see how they were related to one another, and to tapeworms from other parts of the world.

The family tree of tapeworms they got was strangely ancient and alien. In many cases, the closest relatives of tapeworms on Madagascar are not other tapeworms on Madagascar. The tapeworms that live in the southwest part of the island are closely related to tapeworms hundreds of miles away, in Africa. The tapeworms in other parts of the island are more closely related to tapeworms thousands of miles away, in south Asia.

The scientists then tallied up the mutations in each lineage of tapeworm to figure out how long ago they had split off from a common ancestor. All the T. solium tapeworms the scientists studied descend from a common ancestor that lived about 680,000 years ago. The southwest Madagascar tapeworms and the tapeworms of Africa share a common ancestor that lived 235,000 years ago. All of the Madagascar and Asian tapeworms share a common ancestor that lived about 260,000 years ago. The Madagascar tapeworms and their very closest Asian relatives share an ancestor that lived 85,000 years ago.

So how on Earth did one remote island end up with two such deeply split lineages of tapeworms in their pigs? The answer is like a guided tour thorugh the evolution of our species, rolling right on through the history of civilization.

Along with pork tapeworms, there are two other species of Taenia that live in humans. One, T. asiatica, also cycles between people and pigs, but only in Asia as the name suggests. The other, T. saginata, moves between people and cows. Both of these human tapeworms use domesticated hoofed mammals (known as ungulates) as their intermediate hosts. Pigs and cows were only domesticated within the past 11,000 years or so. The best way to find clues to how these tapeworms colonized us is to compare them to the 39 species of Taenia tapeworms that infect wild animals. Eric Hoberg, a parasitologist at the U.S. Department of Agriculture, and his colleagues have found that most Taenia tapeworms form cysts in wild ungulates, such as antelopes, and then become adults in the carnivores that eat their intermediate hosts. The closest relatives of all three human tapeworms live in Africa. Hyenas are the hosts of the closest relatives of pork tapeworms, while lions are the hosts of the closest relative to the other two species, T. saginata and T. asiatica. Hoberg and his colleagues compared the mutations in the DNA of T. saginata and T. asiatica and found that their common ancestor lived somewhere between 780,000 and 1.71 million years ago.

The new results from Madagascar fit in nicely with Hoberg’s results. Hundreds of thousands of years ago, our ancestors lived in Africa, where they scavenged meat from ungulates. In so doing, it appears, they stepped into the life cycle of Taenia tapeworms. Tapeworms that might have ended up in the gut of a hyena or a lion ended up in the gut of our ancestors instead. Over thousands of years, some populations of these tapeworms adapted to our scavenger ancestors. These were the common ancestors of today’s human tapeworms, whose great antiquity is now recorded in the DNA of living tapeworms.

As hominins expanded their ranges both within Africa and beyond it, they carried their tapeworms along for the ride. As hominins scavenged new game, the tapeworms adapted to new intermediate hosts. Hominins gradually developed the skills and weapons to hunt game, offering still more opportunities for their tapeworms. Neanderthals and other hominins hunted wild boar as well, and it’s likely that we infected them with the ancestors of today’s pork tapeworms.

Starting about 11,000 years ago, humans domesticated pigs many times over, both in East Asia and in the Near East. Now the trip from host to host became riduclously easy for the tapeworms. Instead of waiting for its wild boar host getting speared by a hunter, it could make the journey on the dinner plate. Judging from the deep split in the evolution of pork tapeworms, the parasites must have made two separate shifts from wild boar to domesticated pigs, in both East Asia and the Near East.

The genealogy of the tapeworms also matches up nicely with the human history of Madagascar. People only arrived on the island 2000 years ago. They came from two directions. Bantu farmers sailed from the west from Africa across the Mozambique channel. Asians came from the east, traveling thousands of miles across the Indian Ocean from Indonesia. Malagasy culture emerged from the mingling of these two origins. That culture also includes the livestock that the Bantu and Indonesians brought to the island. And those animals brought parasites with them that had been separated for almost 700,000 years, reaching back to a time when our ancestors had yet to invent fire or spoken language.

[Image: Chiang Mai University]

I’m getting lots of email about this bit of pareidolia, purporting to show a shadowy Jesus in some farmland in Püspökladány near Budapest:

But as usual, I see something entirely different. It’s clearly Roger Hodgson, the singer from one of my favorite bands, Supertramp!

I know I’m right; note the hat in both shots. It’s only logical.

Tip o’ the American Breakfast to Michael Meadon, who was the first of many to notify me.

The images of the Pillars of Creation, taken by the Hubble ST April 2, 1995, are considered one of the top 10 most beautiful images Hubble has given us.  It’s easy to see why.

NASA/ESA - Hubble ST

One of the most famous images of modern times.

But – wait.  Some scientists think we’re looking at a ghost.  They think the Pillars were destroyed 6,000 years ago by a nearby supernova.  Since the Pillars are about 7,000 light years away from us, we won’t know for sure for another 1,000 years.

So… how do they know?  Looking at the Pillars through Spitzer’s infrared eyes, six out of seven color images are almost identical.  The seventh image, at 24 microns, is red when it should be blue-green.  Scientists think that the leading edge of a shock wave is what caused the dust and gas in the Pillars to glow red-hot.  A massive shock wave.  The type of shock wave you get when a star goes supernova.

The supernova responsible was probably seen from the Earth one or two thousand years ago.  If so, we’ll see the Pillars torn apart by the slower moving shock wave in another 1,000 years.

Science has always known the Pillars were in danger of being destroyed by a close supernova.  In fact, they had several “candidates” lined up like suspects in a police investigation.  It looks like the “crime” may have already occurred.  Well before the pyramids were built.

Found on PhotoBucket - Very nice enlargement

But, remember;  while we’re watching this “happen” now, it really happened over 6,000 years ago.  And we still have another 1,000 years to go before we see the shock wave fully slam into the Pillars.

When the Pillars do fall, our descendants will get to see all the brand-new baby stars that have been forming inside the Nebula.  Also, you know what happens when a big cloud of dust and gas gets slammed around by a supernova shock wave, right?  Yep… more brand-new baby stars.  And solar systems.  And planets.

Image by Ophelia Joy

It’s the “great circle of life”; writ large.

Still…

Pokeberries, whose red dye was famously used by Civil War soldiers to write letters home, may enable the distribution of worldwide solar power. Researchers at Wake Forest University's Center for Nanotechnology and Molecular Materials are using the red dye from this weedy plant's berries to coat their high-efficient, fiber-based solar cells, licensed by FiberCell, Inc. These fiber cells are composed of millions of tiny fibers that maximize the cell's surface area and trap light at almost any angle--so the slanting sun rays of morning and evening aren't wasted. The dye's absorbent qualities enhance the fibers' ability to trap sunlight, allowing the fiber cells to produce nearly twice the power that flat-cell technology produces. Because pokeberries can grow in almost any climate, they can be raised by residents in developing countries "who can make the dye absorber for the extremely efficient fiber cells and provide energy where power lines don’t run," said David Carroll, the center’s director. According to Newswise:
Pokeberries proliferate even during drought and in rocky, infertile soil. That means residents of rural Africa, for instance, could raise the plants for pennies. The primary manufacturer of the fiber cells could stamp millions of plastic fibers onto a flexible, lightweight plastic sheet, then roll up ...

We’re very happy to have a guest post from Malcolm MacIver. See if you can keep this straight: Malcolm is a professor in the departments of Mechanical Engineering and Biomedical Engineering at Northwestern, with undergraduate degrees in philosophy and computer science, and a Ph.D. in neuroscience. He’s also one of the only people I know who has a doctorate but no high school diploma.

With this varied background, Malcolm studies connections between biomechanics and neuroscience — how do brains and bodies interact? This unique expertise helped land him a gig as the science advisor on Caprica, the SyFy Channel’s prequel show to Battlestar Galactica. He also blogs at Northwestern’s Science and Society blog. It’s a pleasure to welcome him to Cosmic Variance, where he’ll tell us about robots, artificial intelligence, and war.

———————————————————

It’s a pleasure to guest blog for CV and Sean Carroll, a friend of some years now. In my last posting back at Northwestern University’s Science and Society Blog, I introduced some issues at the intersection of robotics, artificial intelligence (AI), and morality. While I’ve long been interested in this nexus, the most immediate impetus for the posting was meeting Peter Singer, author of the excellent book ‘Wired for War’ about the rise of unmanned warfare, while simultaneously working for the TV show Caprica and a U.S. military research agency that funds some of the work in my laboratory on bio-inspired robotics. Caprica, for those who don’t know it, is a show about a time when humans invent sentient robotic warriors. Caprica is a prequel to Battlestar Galactica, and as we know from that show, these warriors rise up against humans and nearly drive them to extinction.

Here, I’d like to push the idea that as interesting as the technical challenges in making sentient robots like those on Caprica are, an equally interesting area is the moral challenges of making such machines. But “interesting” is too dispassionate—I believe that we need to begin the conversation on these moral challenges. Roboticist Ron Arkin has been making this point for some time, and has written a book on how we may integrate ethical decision making into autonomous robots.

Given that we are hardly at the threshold of building sentient robots, it may seem overly dramatic to characterize this as an urgent concern, but new developments in the way we wage war should make you think otherwise. I heard a telling sign of how things are changing when I recently tuned in to the live feed of the most popular radio station in Washington DC, WTOP. The station had commercial after commercial from iRobot (of Roomba fame), a leading builder of unmanned military robots, clearly targeting military listeners. These commercials reflect how the use of unmanned robots in the military has gone from close to zero in 2001 to over ten thousand now, with the pace of acquisition still accelerating. For more details on this, see Peter Singer’s ‘Wired for War’, or the March 23 2010 congressional hearing on The Rise of the Drones here.

While we are all aware of these trends to some extent, it’s hardly become a significant issue of concern. We are comforted by the knowledge that the final kill decision is still made by a human. But is this comfort warranted? The importance of such a decision changes as the way in which war is conducted, and the highly processed information supporting the decision, becomes mediated by unmanned military robots. Some of these trends have been helpful to our security. For example, the drones have been effective against the Taliban and Al-Qaeda because they can do long-duration monitoring and attacks of sparsely distributed non-state actors. However, in a military context, unmanned robots are clearly the gateway technology to autonomous robots, where machines can eventually be in the position to make decisions that have moral weight.

“But wait!” many will say, “Isn’t this the business-as-usual-robotics-and-AI-are-just-around-the-corner argument we’ve heard for decades?” Robotics and AI have long been criticized as promising more than they could deliver. Are there signs that this could be changing? While an enormous amount could be said about the reasons for the past difficulties of AI, it is clear that some of its past difficulties stem from having too narrow a conception of what constitutes intelligence, a topic I’ve touched on for the recent Cambridge Handbook of Situated Cognition. This narrow conception revolved around what might loosely be described as cognitive processing or reasoning. Newer types of AI and robotics, such as embodied AI and probabilistic robotics, tries to integrate some of the aspects of what being more than a symbol processor involves: for example, sensing the outside world and dealing with the uncertainty in those signals in order to be highly responsive, and emotional processing. Advanced multi-sensory signal processing techniques such as Bayesian filtering were in fact integral to the success of Stanley, the autonomous robot that won DARPA’s Grand Challenge to drive without human intervention across a challenging desert course.

As these prior technical problems are overcome, autonomous decision making will become more common. Eventually, this will raise moral challenges. One area of challenge will be how we should behave towards artifacts, be they virtual or robotic, which are endowed with such a level of AI that how we treat them becomes an issue. On the other side, how they treat us becomes a problem, most especially in military or police contexts. What happens when an autonomous or semi-autonomous war robot makes an error and kills an innocent? Do we place responsibility on the designers of the decision making systems, the military strategists who placed machines with known limitations into contexts they were not designed for, or some other entity?

Both of these challenges are about morality and ethics. But it is not clear whether our current moral framework, which is a hodgepodge of religious values, moral philosophies, and secular humanist values, is up to responding to these challenges. It is for this reason that the future of AI and robotics will be as much a moral challenge as a technical challenge. But while we have many smart people working on the technical challenges, very few are working on the moral challenges.

How do we meet the moral challenge? One possibility is to look toward science for guidance. In my next posting I’ll discuss some of the efforts in this direction, pushed most recently by a new activist form of atheism which holds that it is incorrect to think that we need religion to ground morality, and even dangerous. We can instead, they claim, look to the new sciences of happiness, empathy, and cooperation for guiding our value system.

When we last reported on the Deepwater Horizon, the oil rig had sunk in the Gulf of Mexico, but at least the Coast Guard saw no new oil leakage happening. Over the weekend, though, things went from bad to worse as response teams began to see crude oil leaking into the Gulf. Now, the Coast Guard says, 42,000 gallons per day are leaking into the sea, and it may be 45 to 90 days before the leak can be stopped.

Deepwater Horizon, under lease by BP, had been drilling into an oil reserve 5,000 feet below the surface of the water. When the burning rig sank, its 5,000-foot pipeline crumbled like a giant broken straw. The biggest leak has been found at the first crook. The well valve is holding for now but there’s at least one more leak [ABC News]. The Coast Guard couldn’t see the oil so deep under sea right away, which is why the initial assessment wasn’t this bad.

Cleanup teams have now deployed undersea robots to try to stem the oil spill. The best hope is that the remote-operated submarines—at least four are deployed at the scene–would be able to activate a huge device on the sea floor called a “blow-out protector,” a series of valves meant to control pressure in the well. “This is a highly complex operation,” said Doug Suttles, chief operating officer for BP’s exploration and production division. “And it may not be successful” [National Geographic]. If that doesn’t work, the next option would be to drill a relief well to ease the pressure. BP has brought in ships for such an operation, but it would require months to complete.

As we noted on Friday, the spill occurred dangerously close to the United States’ Gulf Coast—within 50 miles. The Coast Guard said the oil spill was expected to stay 30 miles off the coast for the next several days [CBS News]. But as of yesterday, the surface spill had already spread to cover 600 square miles. Whether it gets closer to U.S. shores depends on how the weather changes. Louisiana is already taking precautions, deploying containment booms around particularly sensitive areas along its coast. The oil spill is reportedly edging closer to the Chandeleur Islands, which are part of a wildlife refuge for pelicans and other seabirds; the fish and shrimp that live in Louisiana’s rich coastal ecosystems could also be threatened.

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Image: United States Coast Guard