Showing posts with label elephants. Show all posts
Showing posts with label elephants. Show all posts

Friday, May 14, 2021

Biking Chiang Mai To Bangkok This Summer In Anchorage

 Back around Fall 1981, the University of Alaska Anchorage swimming pool had a challenge - swim the Bering Sea over the semester.  In the pool.  50 miles.  I've never been as fit as I was that semester.  Each swim was not just a swim, but a leg across the Bering Sea.  That was a lot of incentive to get in the pool three or four times a week.  

So last summer I decided I should have a mental trip in mind for my biking.  I chose Santiago Chile to Concepción - a distance of about 650 kilometers, depending on which route you take.  So, as I rode last summer, I was in Anchorage, but also in Chile.  I looked at maps and pictures of the places I was passing.  Just like swimming the Bering Sea, riding from Santiago to Concepción was the inspiration I needed to get on the bike, even on days I was feeling lazy.  And once out, I never regretted it.  

So I've started already this summer and thought about going from Chiang Mai to Bangkok.  I wasn't exactly sure how far that was, but it seemed in the ballpark.  I looked on line to see if it was doable.  Not only is it doable, but there are a number of companies that will take you on the actual trip and so I picked Exo Travel because their trip was 745 km and the itinerary included a stop in Kamphaengphet - a town I lived in for two years teaching English.  I've also spent six months in Chiang Mai over two years and about a year in the Bangkok area.  


I've added up the miles from Exo Travel's itinerary and marked the distance from Chiang Mai for each daily destination.  The 165 km from Kamphaengphet to Nakhon Sawan would be way too much for me to do in one day.  I think about that trip on the main road back in the late 1960s.  It was a red dirt road.  Very dusty. Lots of rice paddies and some interesting hills jutting up oddly out of the earth.  Of course, it's paved now - they were working on that back when I was first there.  

So, as of today, I've ridden about 102km.  (That doesn't count three or four early, shorter rides on the old mountain bike before the ice was totally gone.)  

So let's look at today.  Before riding I swept the cottonwood catkins off the deck.  I have to do that twice a day right now.  









The catkins are VERY sticky.  If I don't sweep they stick to the deck, except for the ones that stick to my shoes.  Very messy period every year.  But they do smell very sweet.  

The tulips opened today.  At least two of them did.






There was a moose browsing by the trail as I went past the UAA student housing.  I'm always amazed at how such huge creatures can be so well hidden out in plain sight.  



Then up the trail toward Stuckagain Heights and Campbell Airstrip.  



Here's the north fork of Campbell Creek as it crosses under the Stuckagain Heights road.  

So given my bike rides so far since April including today, I've covered 102 kms, so I'm about 20 kms out of Lampang.  This is an old northern town that still has horse drawn carriages you can use to get around town.  There are no moose, but the elephant sanctuary is nearby.  

Here's are some links to posts I did at the elephant sanctuary in Lampang.

Elephants Part 1

Thai Elephant Conservation Center Hospital in Lampang and the Nursery (Part 2)



Sunday, January 27, 2019

Joel Sartore's Photo Ark



 Here's a post I forgot to put up.  We stopped at the Annenberg Space For Photography when we were in Los Angeles.

These posters were on the street light poles on my bike ride to the beach, but I'd never been to the Annenberg.

This museum is in Century City and is free, but parking is $4.50.  But if you get there after 4:30pm, it's only $1.50.  Since it's a small space and it closes at 6:00pm, there's enough time.

Joel Sartore is the photographer.




















The photos are magnificent.  I only had my little camera to take pictures of pictures.  This one is a close up of his photo.













































Despite humans' greater abilities to think and communicate, those abilities too often are used to destroy the natural habitats of these animals.  Whether by turning natural spaces - forests, plains, jungles, shorelines, wetlands - into farmland, oil fields,  mines, housing, battlefields, or simply cutting the trees or taking all the fish, we have radically endangered a multitude of species.

And that's not to mention how climate change further threatens the animal world.

This exhibit is a reminder of the mass plundering humans have done and the diversity of amazing animals we're likely going to wipe off the face of the earth.   Sorry this is blurry, but it's all I have of this message.





Monday, January 14, 2019

Genesis 2.0 - Mammoth Hunters Of Siberia



We just got back from a strange documentary film about Siberian native men who go searching for ancient  mammoth tusks in islands in the arctic and sell them to Chinese.  They find a whole mammoth - it bleeds when they accidentally hit the flesh with an ax -  and eventually parts of it go to the South Korean genetics lab of Woo Suk Hwang that clones dogs for $100,000 a pup for those who can't bear their dogs' death.  Woo Suk Hwang hopes to find a living cell in the ancient mammoth flesh so he can clone it.

At the end we watch  interspersed shots of the native men trudging across the tundra on ancient - and very smoky - off road vehicles  and shots of visits to super new genetics labs in Korea and China.

My gut reaction to what was going on - raking the mostly untouched tundra for ancient bones, then the Korean cloning factory - seemed at odds with the film's apparent support for the activities it was portraying, but eventually the film seemed to twist in my moral direction.  There was an early hint as traditional poems were read that warned the local people not to dig in the earth and not to be seduced by the spirits that tempt them there. There was mention of native taboos for touching the bones and flesh of the buried mammoths.  Later, after seeing the Korean cloning king showing off his prowess, even watching a Caesarean birth of cloned puppies, the film briefly mentions that Woo Suk Hwang had been shown to have committed fraud in past scientific journal articles,  Then, during the visit to BGI, a giant Chinese genome sequencing lab, a Swedish scientist in the party raises ethical questions after the guide talks about using sequencing to prevent Downs Syndrome babies (our cash cow she says).  Toward the end we once again hear the traditional warnings against digging into the earth and tempting sprites and spirits who live there.  Finally the men get their tusks back to the Siberian mainland where a Chinese buyer inspects them - not very good quality - and we're told that 20-30,000 tons of mammoth tusks are undug every year!  The film ends when the camera man is told to stop filming while the native men are selling their tusks.   It was called Genesis-2.0.  

Global warming is unearthing artifacts frozen in the perma-frost for tens of thousands of years.  This film offers us a glimpse of what that actually means. The people involved, and the stark contrast between the rough wilderness conditions where the bones are found, and the super-modern genome factories.  Lots to digest.  (Yes, one of the native men who found the ancient flesh mentioned that eating raw meat was part of his culture, as he tasted the flesh.)

Saturday, December 24, 2016

Spending Afternoon In The Late Pleistocene Epoch




The UC Museum of Paleontology gives the dates of the Pleistocene as 2.6 million to 11,700 years ago and says the La Brea Tar Pits is "one of most famous Pleistocene fossil localities anywhere."

The tar pits is one of my good childhood memories.  Before the LA County Museum of Art was there.  Before the Page Museum was there, it was just a big park with giant, climbable  statues of the long extinct big mammals that lived then - mammoths, mastodons, saber tooth tigers, and giant sloths.  And there were live rabbits hopping about the park.  And, of course, the scattered pools of tar that entrapped so many of the animals.

So it seemed a good place to go with our granddaughter and we spent the whole afternoon there.

We took the tour, and the guide - he was really good - took on some of the myths and misnomers surrounding the tar pits.  First, they were really asphalt* pits.  Tar, he said, is man made.  Second, the animals who got stuck in the pools, didn't get sucked down like in quicksand, but tended to stay on the surface and die of hunger or thirst or from predators.  And this iconic set of mastodons is a little more Hollywood than real.

The animals at the tar pits are from the late Pleistocene era - 10,000 - 50,000 years ago.  So, no dinosaurs.  Just animals that lived when humans were around.  And whether these large mammals went extinct because the Ice Age ended or people got better at killing them or diseases is still in debate.

The museum offered lots of examples of fossils from the era and simulated versions the many of the animals and birds.  There are also people actively sorting through bones still today.

This woman (and two others) were sorting through material with paint brushes and magnifying glasses and microscopes to separate non-fossils from fossils.  The collect fossil insect parts and even plant seeds.


The building itself is mostly underground, with grass slopes built up around it.  My granddaughter had fun 'jumping off' the roof, the running down the sides and back up again.   (The 'roof' is actually that whitish wall, not the top grey facade which has a frieze depicting animals of the period.)  As you can see if you look carefully, it had rained heavily the night before, and as you can't see, it would rain again that night.


Click on any of the images to enlarge and sharpen them

Altogether a good afternoon for the oldsters and the youngster.  



*for a distinction between tar and asphalt, check here.
For a long and interesting pdf on asphalt, check here.

Tuesday, October 20, 2015

Elephants Cooperate, So Do People, Which Is Why I Couldn't Tell You About This Experiment Six Years Ago

From the new* Scientific American (I can only read the intro without paying):
"At the Thai Elephant Conservation Center, tucked away in the trees near Chiang Mai, a pair of Asian elephants gazes at two bowls of corn on the other side of a net. The corn is attached to a sliding platform, through which researchers have threaded a rope. The rope's ends lie on the elephants' side of the net. If only one elephant pulls an end, the rope slides out of the contraption. To bring the food within trunk's reach, the elephants have to do something only humans and other primates were thought to do: they must cooperate. Working in synchrony, each elephant grabs its end of the rope in its trunk and pulls, drawing the platform and the treats within reach."

photo from my April 2009 post
We met Josh Plotnick, the experimenter, in Chiangmai, in 2008.  We went to visit the elephant conservation center in 2009 where we saw his elephants and the experiment he was doing.  But I could only hint back then.  Here's from my first post on the elephant sanctuary in Lampang then:
"JP is a doctoral student doing his dissertation research here at the center. We met him last year and finally got a chance to go out and visit him in the center. His research is very interesting but I was sworn to silence until his work is published."
Here's a link to the second post on the sanctuary which focused on the hospital and nursery.


*It's hard figuring out online what the date of this Scientific American is.  It says, "

Saturday, June 13, 2015

How Plastics Saved The Elephant

I ran across a Scientific American article on the history of plastic.  It reminded me how much history has to teach us and how much of it we don't know. 
Thai work elephants 1967-8
"elephants, the paper warned in 1867, were in grave danger of being "numbered with extinct species" because of humans' insatiable demand for the ivory in their tusks. Ivory, at the time, was used for all manner of things, from buttonhooks to boxes, piano keys to combs. But one of the biggest uses was for billiard balls. Billiards had come to captivate upper-crust society in the United States as well as in Europe. Every estate, every mansion had a billiards table, and by the mid-1800s, there was growing concern that there would soon be no more elephants left to keep the game tables stocked with balls. The situation was most dire in Ceylon, source of the ivory that made the best billiard balls. There, in the northern part of the island, the Times reported, "upon the reward of a few shillings per head being offered by the authorities, 3,500 pachyderms were dispatched in less than three years by the natives." All told, at least one million pounds of ivory were consumed each year, sparking fears of an ivory shortage. "Long before the elephants are no more and the mammoths used up," the Times hoped, 'an adequate substitute may [be] found.'"
 Plastics.  It's mind boggling to know that humans nearly wiped out elephants 150 years ago, just so they could play billiards!

The savior of the elephants?
Plastics freed us from the confines of the natural world, from the material constraints and limited supplies that had long bounded human activity. That new elasticity unfixed social boundaries as well. The arrival of these malleable and versatile materials gave producers the ability to create a treasure trove of new products while expanding opportunities for people of modest means to become consumers. Plastics held out the promise of a new material and cultural democracy. The comb, that most ancient of personal accessories, enabled anyone to keep that promise close.
There was even a contest to find a substitute for ivory so they could keep making billiard balls when the supply of ivory was gone.

The need for natural material to make combs almost wiped out the hawkbill turtle.  In fact plastics - first made from plant material and then from oil - saved a lot of creaturers.
Celluloid could be rendered with the rich creamy hues and striations of the finest tusks from Ceylon, a faux material marketed as French Ivory. It could be mottled in browns and ambers to emulate tortoiseshell; traced with veining to look like marble; infused with the bright colors of coral, lapis lazuli, or carnelian to resemble those and other semiprecious stones; or blackened to look like ebony or jet. Celluloid made it possible to produce counterfeits so exact that they deceived "even the eye of the expert," as Hyatt's company boasted in one pamphlet. "As petroleum came to the relief of the whale," the pamphlet stated, so "has celluloid given the elephant, the tortoise, and the coral insect a respite in their native haunts; and it will no longer be necessary to ransack the earth in pursuit of substances which are constantly growing scarcer."
 As the human population increases, we make heavier use of critical materials, up to the point that we may use them all up - and in the case of animal based materials, cause extinction.  If we are lucky, we find a substitute to give relief to those natural sources. 

But then we get dependent on the new material to the point of endangering the natural world again.   And the local humans who live in that now destroyed natural environment.

Our petroleum use, which saved the whale a hundred years ago, is now causing climate change.  Today petroleum based sports enthusiasts, like the billiard players, continue their dangerous games.  But the rest of us are guilty too.  We can't get free of our addiction to fossil fuel powered cars and airplanes and electricity.   Some, though, are rushing to create alternative sources of energy and finding ways to wean humans from oil. Meanwhile those companies that have gotten rich off of fossil fuels, are fighting any curtailment of the source of their wealth and we continue to buy their products to fuel our lifestyles which we can't imagine without fossil fuels.

And our search for other natural resources as well as our growing human population's encroachment into forests continues to make the survival of non-human species like the elephant and the tiger and millions of smaller, non-iconic species iffy. 

The whole article is fascinating and has lots more details.

Monday, September 03, 2012

Elephant Beggars Follow Up

Elephant and mahout coming to beg at Chiang Mai restaurant 2008
Four years ago, I posted about elephant beggars in Chiang Mai, Thailand.  Today I got this email:
"I typed a response to your post about elephants begging in Chiang Mai, but when I clicked the preview button the post disappeared. That is why I am emailing you now."
[I get complaints now and then about how hard it is to leave comments.  I'm sorry for the inconvenience, but enough spam messages get through with the Blogspot obstacles, that I'm not ready to turn them off.  I trust my readers to be persistent enough to stick with it until their comment gets through, or, as Tim did, just send me an email.]
"In late 2010, a mahout, using as a weapon his metal-tipped wooden mahout stick, severely beat a couple of Australian tourists, who'd attempted to lecture the mahouts on the ethical treatment of animals. The mahout, and several others who'd been with him at the time of the beating, were arrested. The mahout was charged with some minor offense. All were released the following morning and were back with their elephants on the street within twenty-four hours of the attack. The Australians required hospitalization. The fallout of this awful event was such that the local Thai authorities decided it was time to rid Chiang Mai of the mahouts and their elephants. To that end, the police and the mahouts had a little meeting, which resulted in the mahouts and their elephants being shipped back from whence they came, a province along the Cambodia border. The mahouts, having successfully argued that they must beg in order to feed their elephants, are now subsidized. Or so the story goes. I was living in Chiang Mai at the time, and still am, but was away from Thailand when all this transpired. I've read the seder guest's comment about the elephants being owned by wealthy Thais. That makes this story even more interesting. Living in Alaska is a life-long fantasy of mine. Someday I'll get there. Best wishes, Tim"

I emailed back to Tim to get permission to post his email and found out he's a musician living in Chiang Mai but working in other Asian countries.  He also sent a Bangkok Post article on the attack.

I did some check up on this, including contacting Josh Plotnik who'd we met in Chiang Mai when he was doing his doctoral dissertation studying elephant behavior at the Thai Elephant Conservation Center in Lampang.  Josh is now doing post-doctoral studies at Cambridge University, though he's spending most of his time in Northern Thailand where he's set up an organization called Think Elephant International.  The website explains the reasons behind of Think Elephant:

Why We Think Elephants
The loss of natural habitat, poaching for ivory, and human-elephant conflict are serious threats to the sustainability of elephants in the wild. Put simply, we will be without elephants, and many other species in the wild, in less than 50 years. Although conservation and wildlife management are not new ideas, clearly new approaches are needed. Think Elephants International is a non-profit focused on practicing science in the field, and teaching it in classrooms. Through research on elephant (and other animal) intelligence, we hope to better inform conservation practice in the wild by helping to formulate action plans that along with focusing on the needs of local human populations, take advantage of what we know about the animal's needs as well. Our research focuses on how elephants "see" their natural world – through smell and sound – and how they navigate this world – through problem solving and cooperation. Equipped with a better understanding of how these animals live, we hope to better help protect them in the wild.
Think Elephants is something else as well – an organization focused on conservation through education. But we don't just teach kids about the conservation battle, we bring the battle to them by bringing the elephants into their classrooms.
Josh confirmed Tim's report:
"The begging elephants situation is extremely complex -- yes, most of the eles were removed from the streets of Bangkok, and went home to Surin. In Surin, the government does subsidize the elephants and thus the mahouts get to stay home for 7,500THB [$240] a month (approximately). Unfortunately, I hear the eles are slowly making their way back to the streets in outlying provinces."

He also sent me to John Roberts' blog for the Golden Asian Triangle Elephant Foundation
(GTEAF*).  Their website describes (in part) their work:
"Yet, despite the strong bond between Thai people and their nation’s most genteel species, there are still a worrying number of elephants forced to walk the city streets to make their mahout a miserly living by begging from tourists.
In an ideal world all elephants would live in the wild and there would be no need to discuss elephants' work.  But until that point is reached, the GTAEF also aims to create and promote ethical work for the elephants and mahouts that are capable, whilst providing care for those that are unable."
Roberts, who is the Director of Elephants at Anantara Golden Triangle’s on-site Elephant Camp, wrote in a blog post just over a year ago (again, in part):
. . .You see, I believe (& I do have some idea which elephants are out there and what their history is) that there exists a perfectly reasonable (and improving) alternative back in the home town of these mahouts, an alternative provided by the Government (& improved for as many as possible by The Surin Project).
Not only is a viable alternative provided it has been very strongly explained to the mahouts that the penalties for being on the streets will be enforced.  “Go back home”, the authorities say, “we may not be able to make you rich there but we’ll keep you & your elephant there in the bosom of your family and, what’s more, if you come back out it’s ‘no more mister nice guy’, powerful people have noticed you, we’ll have to make your life a misery”
To me, that the message has hit home and so many elephants are still in Ban Ta Klang (in previous times when this approach was tried the elephants would stay until their existence became untenable: the food ran out or the money ran dry) means that this time, this IS a viable alternative.
So, I believe that the mahouts out there on the streets now, at least the ones I know about, have few excuses left (...a tendency toward an itinerant lifestyle?  ...a nagging wife?) - it is my belief that they are there for financial gain.  Believe it or not, the natural graze out on the streets may, at times, be better than can be found back at home but I believe the decision to go back out (most came home then went out again) was a purely financial one and has very little justification in ‘traditional lifestyle’ or ‘elephant welfare’ terms and none at all in the ‘no alternative’ terms. . .
You can follow Roberts' blog, Elephant Tails , here.  The most recent post is about selling coffee beans that have been processed by having elephants eat them before they are roasted.  Come on now, it's not that strange.  After all earlier this year I did a post about acacia trees whose seeds had to go through a giraffe's digestive system before they could germinate. 

Clearly there is a lively 'elephant world' out there that I've only glimpsed into. 

This post is long and convoluted enough.  I'll try to do another one on elephants soon though.

*GTAEF, from what I can tell, is a project of Anantara, a luxury hotel chain, that caters to the wealthy (I checked on a room in their hotel by the elephant camp and it started at over $1000 per night.  We stayed a night once in nearby Chiang Rai, in what we thought was a pretty fancy hotel for $35 per night.  That was an internet discount, but they weren't losing money on that price.)  This could be a great example of what's known as social entrepreneurship - using the market to support important non-profit causes.  Or it could be using green issues as a marketing ploy.  I just don't know enough about the organization to evaluate. 

Tuesday, October 04, 2011

Autopsy on 42,000 Year Old Corpse - Mammoths and Mastodons

We stopped by the Anchorage museum's visiting Mammoths and Mastodons Exhibit Sunday.  It will be here until Sunday October 9 for those of you who have been putting it off.


There are lots of pictures and replica's of mammoths and mastodons - some you could hold and others life size.  .   There are lots of "Please Touch" signs. There are also lots of videos and interactive exhibits  A good one was the cave where you can use a remote control to shine light and identify some of the drawings on the walls.
But the exhibit that grabbed me most was Lyuba.  This is a life size replica of a complete one month old mammoth found in Russia.







Click to enlarge and make clearer


Great video describing Lyuba, how she died, how she was found, and how they learned from her.

[UPDATE May 22, 2012: Here are two videos from National Geographic. I think there were parts of these two, plus another in the video we saw. The first is about the discovery of Lyuba:

Here's a link to a video of the discovery of Lyuba. (I couldn't get the embed code to work.) The second is of the autopsy:








Any idea where or when the most recent mammoth tusks were found?






3,700 years ago isn't that long a time.  There were some relatively sophisticated human societies living then in China and the Middle East.


And then we went outside, got rid of most of our clothes and went Mastodon hunting behind the museum.

Thursday, July 30, 2009

is maggie the elephant's anchorage zoo stall still empty?

Someone got to a guest post here on Maggie's first anniversary at her new California home by googling the question above.

So I called the zoo to find out. I was told that it is empty right now, but over the winter they had two brown bear cubs that had been brought in (separately) and were not in condition to hibernate and they were kept for the winter in the elephant house.

And this is why I'm not a particularly good journalist: I forgot to ask where the bears are now. But you can see pictures of the cubs at the website of the zoo photographer, John Gomes.

Thursday, April 02, 2009

Thai Elephant Conservation Center Hospital in Lampang and the Nursery (Part 2)

For anyone who wanted to see more of JP's research on elephant self recognition in mirrors, here's a link to the published article with videos . And here's another link to his interview on National Public Radio.



Can you see the Thai word for elephant hospital in both signs? I ask that only because most people just see seemingly impossible script, but if you look closely, you can see the letters. The last three letters of the top line of both pictures is 'elephant' - ช้าง. "Chang" The little up above means it's high tone. Note also that letters look a little different in different fonts. The letters in front of ช้าง spell hospital.

Below is a list of the names of the elephants in the hospital when we were there on Wednesday. I would have photoshopped the three pictures together, but the final picture would have been way too small to read anything.

As it is you may want to double click to enlarge the pictures.


Owner indicates how the elephant got here. Anyone can send their sick elephant here for treatment. Confiscated seems to include Burmese elephants that somehow got into Thailand.


You probably have to enlarge this one, but it's the list of reasons
why each elephant is in the hospital.

This one was the most obviously injured. Probably this was a logging accident.


So this isn't the last picture you see here, here are some pictures from the elephant nursery.

This baby was four months old if I recall correctly.


And this one was eight months old.


Wednesday, April 01, 2009

Elephants - Part 1

[Thursday, April 2, 2009 12:30am Thai Time]
The bus to Lampang (about 90 km south of Chiang Mai) dropped us off in front of the Thai Elephant Conservation Center and we called JP who told us to get our tickets and ride the shuttle up to the showgrounds. Here's another site that has videos of Center.



On the way up we saw this board next to information on getting a day of Mahout training.

The show focused more on skills the elephants had that made them so important for getting timber from the forest to the roads. But most such work is no longer available in Thailand because the government has programs to protect teak forests.


The show also included a non-traditional Thai elephant activity - painting.




Here are the three paintings we saw the elephants paint.


Apparently, elephants have very good control with their trunks and can do this sort of painting, but these representational paintings are done with close supervision from the mahouts. But when painting on their own, the elephants do much more abstract work than this. But the Center sells the paintings so this is a form of fundraiser.


After the show, people got to feed the elephants. A bunch of little bananas was 20 Baht ($.60). Most of the other visitors were Thai, though there were a a few other foreigners.



JP is a doctoral student doing his dissertation research here at the center. We met him last year and finally got a chance to go out and visit him in the center. His research is very interesting but I was sworn to silence until his work is published. But an earlier paper he published as a masters student on how elephants recognize themselves in mirrors. Here's the abstract:

Considered an indicator of self-awareness, mirror self-recognition (MSR) has long seemed limited to humans and apes. In both phylogeny and human ontogeny, MSR is thought to correlate with higher forms of empathy and altruistic behavior. Apart from humans and apes, dolphins and elephants are also known for such capacities. After the recent discovery of MSR in dolphins (Tursiops truncatus), elephants thus were the next logical candidate species. We exposed three Asian elephants (Elephas maximus) to a large mirror to investigate their responses. Animals that possess MSR typically progress through four stages of behavior when facing a mirror: (i) social responses, (ii) physical inspection (e.g., looking behind the mirror), (iii) repetitive mirror-testing behavior, and (iv) realization of seeing themselves. Visible marks and invisible sham-marks were applied to the elephants' heads to test whether they would pass the litmus “mark test” for MSR in which an individual spontaneously uses a mirror to touch an otherwise imperceptible mark on its own body. Here, we report a successful MSR elephant study and report striking parallels in the progression of responses to mirrors among apes, dolphins, and elephants. These parallels suggest convergent cognitive evolution most likely related to complex sociality and cooperation.
You can read the whole article at the Proceedings of the National Academy of Sciences.