Jonathan Crowe

I’m a blogger and writer from Shawville, Quebec. I’m best known for DFL and The Map Room. Lately I’ve been reviewing science fiction at AE and editing a fanzine called Ecdysis. More about me.

My Correct Views on Everything
↳ Reptiles & Amphibians

Black Pine Snake Listed as Threatened

The Black Pine Snake (Pituophis melanoleucus lodingi) will be designated as a threatened species under the U.S. Endangered Species Act. The U.S. Fish and Wildlife Service proposed threatened status for this snake about this time last year; the listing will now take effect on November 5.

Can Snakes Hear? (Hint: Yes)

Snakes are inscrutable and mysterious. That’s probably why so many people ask so many basic questions about their biology. (One I’ve run into a few times: do snakes have bones? The answer is yes, lots of them, but the question belies a confusion about what a snake is: they think it’s some variant of worm.)

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Snake Fungal Disease

This week the Associated Press ran a story on snake fungal disease, its devastating impact on wild snake populations (especially rattlesnakes, which appear to be particularly susceptible), and the scramble by biologists to understand it. I’ve been hearing about snake fungal disease for a while, and it’s made the news before: see this 2012 Boston Globe story. But the AP story provides some chilling statistics: for example, among massasaugas in Illinois, an annual 15 percent infection rate and an 80 to 90 percent mortality rate. Rattlesnakes don’t reproduce fast enough to sustain such losses, so they’re in big trouble.

More on snake fungal disease from, the Wandering Herpetologist and Northeast PARC (PDF).

Previously: An Amphibian Typhoid Mary.

Tokyo’s Snake Café

There are cat cafés and even owl cafés, so it’s only right that there is now a snake café. Of course it’s in Japan: the Tokyo Snake Center, where for ¥1,000 you can have a snake sit with you as you enjoy your drink, or for another ¥540 you can handle one. This strikes me as serving an unmet need: lots of people want to encounter and hold snakes, but pet stores and zoos aren’t always the best place for it. As a snake keeper, I don’t see anything out of the ordinary here: the Japan Times video shows that the species are standard pet store varieties, the individual snakes seem calm and gentle and acclimated to human contact, and they seem to be looked after properly. This isn’t all that different from the public outreach programs that many reptile zoos and hobbyists do; it’s just in a different setting. Via MetaFilter.

About That Four-Legged Fossil Snake

Exciting news last week for those of us interested in the evolution of snakes: the announcement that a fossil snake with four legs has been discovered (abstract). The 20-cm long fossil of Tetrapodophis amplectus, which dates from the early Cretaceous, has lots of snake-like characteristics despite the legs.

But what’s controversial about the fossil is its murky origins. It came from a private collection with no locality data, but the researchers believe it came from a formation in northeastern Brazil. The problem is that it’s been illegal to export fossils from Brazil since 1942, which means that the Tetrapodophis fossil may have been illegally collected. Which is to say that this is potentially massive discovery may well be tainted.

I can’t help but wonder whether the issue isn’t just legality, but chain of evidence — if you can’t document where the fossil came from, how do you prove that it’s legitimate? That it isn’t another Archaeoraptor or Piltdown Man — two missing-link fossil discoveries that later proved false?

Previously: The Oldest Known Snake; The Biggest Venomous Snake Ever; A Cretaceous Snake with a Lizard’s Head.

Conservation Through Identification

When you have a snake website with a contact form, as I do, you inevitably get questions from readers asking you to identify a snake for them. I’m usually happy to oblige, because, inevitably, they’re worried about something harmless and I’d rather they not kill it. (I’d rather they not kill the dangerous snakes either, but you do what you can.)

Answering people’s questions as they come in is a passive approach. But biologist David Steen has gotten rather more proactive: he scours photos of snake encounters posted to Twitter, usually by people who think they’ve come across a copperhead or a cottonmouth, and — very gently — corrects them from his @AlongsideWild Twitter account.

In a similar vein, Pennsylvania reptile rescuer Jesse Rothacker has been offering a free snake identification service: send him a photo via text, e-mail or his Facebook page and he’ll identify it. (He created a meme image that went viral, and got buried with requests, so he’s since had to limit the offer to Pennsylvania snakes.)

The Great Snake Weigh-in of 2015

Male Okeetee corn snake: 778 grams.Female checkered garter snake: 368 grams.Lucy the bullsnake: 1.537 kg

This month Jennifer and I started doing something we’ve been meaning to do since the fall of 2013: weigh all the snakes in our menagerie. It’s something neither of us has ever done before; we’d had vague ideas of the approximate weights of our various critters, but that’s about it.

Our method was pretty straightforward: tare the scale, stick the snake on it, and take its picture. Those of you who follow me on social media will have seen the photos already; I’ve assembled them into a photo album here.

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Taxonomic Changes to Crayfish, Swamp and Earth Snakes

I’m always afraid to check the CNAH website: there’s always some new study that renames or reclassifies everything. It’s been a while since the natricine snakes have been done over, though. A 2013 phylogenetic study of two North American natricine genera — the glossy and crayfish snakes (Regina) and the earth snakes (Virginia) — concludes that they’re not monophyletic. They split off two crayfish snakes and group them with black swamp snakes in a new genus, Liodytes, and split the earth snakes into two monotypic genera.

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Irwin’s Controversial Legacy

Steve Irwin died in 2006. Smithsonian looks at his legacy, and how his family today straddles the uncomfortable divide between conservation and showmanship, much as he did during his life:

What’s perhaps surprising is that Irwin, though controversial for his flamboyant hands-on approach to wildlife, quietly teamed with serious scientists and conservationists to make a genuine contribution to the systematic natural history of this enigmatic critter. Their discoveries about the salties’ habits, homing abilities and private lives have prompted a rethink of how they live and how we can coexist with them. Adult crocs have no natural predators except people, possibly because we’re meaner.

At a time when nature preserves are becoming more intensively managed, and zoos and aquariums are becoming more involved in field conservation, the line between “the field” and “animal holding facility” has blurred. By straddling both worlds, Irwin was smack in the middle of the quandary over the trade-off between protecting animals in the wild and studying them in captivity. Today, that quandary is further complicated by his family’s link to SeaWorld, harshly criticized since the 2013 documentary Blackfish for its treatment of killer whales and the subject of a withering new book by one of its former trainers.

Charge Revealed in N.B. Python Case

We now know the charge being faced by the owner of an African Rock Python that killed two young boys: criminal negligence causing death. CBC News and the Canadian Press are reporting that today. Jean-Claude Savoie was arrested on February 5 but the charge was not specified at the time. Savoie is the former owner of an exotic pet store in Campbellton, New Brunswick; the four-metre-plus, 45-kilogram python escaped its cage and asphyxiated the boys as they slept during an overnight stay.

Previously: About the Python in New Brunswick; Campbellton Python Incident Update; At the Pointy End of a Moral Panic; More Updates on the Python Incident; Python Truthers Are a Problem; Arrest, Charges in N.B. Python Case.

Arrest, Charges in N.B. Python Case

Remember the incident in Campbellton, New Brunswick in August 2013, in which a 14-foot African Rock Python escaped from its cage at an unaccredited zoo/pet store and killed two small boys? There’s been a development: the owner of the facility, Jean-Claude Savoie, was arrested in Montreal yesterday. He was released the same day but will appear in court in Campbellton on April 27. Only then will we know what charges he’s facing: the authorities aren’t saying at this time. The investigation is still under way. But it’s a fairly good guess that Savoie is facing criminal charges of some sort, rather than charges under provincial wildlife law — the window for laying those charges has apparently already passed.

Previously: About the Python in New Brunswick; Campbellton Python Incident Update; At the Pointy End of a Moral Panic; More Updates on the Python Incident; Python Truthers Are a Problem.

The Oldest Known Snake

What is the definition of a snake? If you said “legless reptile” you’d be wrong: there are two families of legless lizard as well as amphisbaenians (which are just weird, especially these things). If I remember correctly, a snake is defined by its skull, which differs from other squamates: it’s thin, delicate, mobile and articulated. It was that definitive skull that led a team of researchers, headed by University of Alberta paleontologist Michael Caldwell, to identify four species dating from 140 to 167 million years ago as snakes rather than lizards, putting the emergence of snakes far earlier in the prehistoric past. (Snakes were previously thought to have evolved around 100 million years ago: the gap in the fossil record is not really surprising given how poorly delicate snake skeletons fossilize.) The findings suggest that the snake skull may have evolved before snakes lost their legs. Article abstract. News coverage: CBC News, Discovery News, Live Science, University of Alberta.

A New Species Hiding in New York City

Rana kauffeldi

Last month an article published in PLOS ONE confirmed the existence of a new species of leopard frog — the Atlantic Coast Leopard Frog (Rana kauffeldi) — along the Eastern Seaboard. (News coverage: CBC News, Wired.) Its range runs from central Connecticut to at least Northern New Jersey — including New York City — and possibly to North Carolina. How does a species found in such a densely populated area stay undiscovered for so long? Because discovering a new species is often an exercise in reclassifying known populations, rather than discovering new animals: cryptic species that were thought to be something else. In this case, the more broadly distributed northern and southern leopard frogs, from which R. kauffeldi was isolated by genetic data and its distinctive call. (Image credit: Male R. kauffeldi, from the article by Feinberg et al., Creative Commons licence.)

The Biggest Venomous Snake Ever

In 1857, Richard Owen described a gigantic viper, Laophis crotaloides, on the basis of 13 vertebrae found in early Pliocene rock formations in Greece. Owen’s fossil holotypes for Laophis have since been lost; it’s taken until now for Owen’s find to be confirmed in a paper presented at the annual meeting of the Society for Vertebrate Paleontology this month, with the discovery and description of a single vertebra. (I have learned that sometimes that’s all that’s needed). At an estimated length of up to three metres and an estimated mass of up to 26 kg, Laophis crotaloides was a whopper of a viper — hardly Titanoboa cerrejonensis, but quite a bit bigger than the largest venomous snake today, the king cobra (Ophiophagus hannah), whose largest reported specimen weighed in at 12 kg. Via

Threatened Status Proposed for Black Pine Snake

Lucifer eats a rat

The U.S. Fish and Wildlife Service is proposing to list the black pine snake (Pituophis melanoleucus lodingi) as a threatened species. Popular in the pet trade (I’ve had a pair since 2000), the black pine snake has a limited and dwindling range: it’s disappeared from Louisiana and is now found in a handful of counties in Alabama and Mississippi. The FWS cites habitat loss, fragmentation and degradation, killing by humans and pine snakes’ low reproductive rates (they have small clutches) as factors in the subspecies’s decline.

Notably, the pet trade is not cited as a factor; it’s “currently saturated with captive-bred black pinesnakes.” I can’t quite figure out what impact threatened status will have on that saturated pet trade. But however much we enjoy our captive black pine snakes (and they really can be quite lovely animals: I frequently compare ours to black Labradors), the needs of the wild population must come first.

The snake has been on the cusp of being proposed for protection for decades. The proposal opens a 60-day period for public comments; the final listing would probably come some time next year. News coverage.

The Evolution of Combat and Courtship Behaviour in Snakes

Male snakes of many species engage in ritualized combat during mating season, and snake courtship also has specific behaviours. A recent article explores the evolution of those behaviours. ScienceDaily: “The authors of this study analyzed 33 courtship and male-to-male combat behaviors in the scientific literature by plotting them to a phylogenetic tree to identify patterns. The authors identified the patterns in behaviors, which was not always possible, and then used the fossil record to match the behaviors to the snakes’ evolution.”

Encountering Racers

Blue Racer

Last month I had the opportunity to encounter some Blue Racers in captivity. They’re one of the many prides and joys of the Scales Nature Park, a small zoo just south of Orillia, Ontario, that focuses on Canadian reptile, amphibian and fish conservation. I’ve known the owner/operator for nearly 15 years.

Racers (Coluber constrictor) are interesting snakes: they’re fast, diurnal, visually oriented, and eat just about anything that moves. But they’re hardly ever kept in captivity, mostly because in addition to the above, they have a reputation for being extremely and repeatedly bitey. Which is kind of a disincentive (not that it’s ever stopped people keeping tree boas, but that’s a different story). I don’t necessarily have a problem with that: there are hundreds of kinds of snakes that would make better captives; keep one of those instead.

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More Adventures in Snakekeeping

  1. No worries about her feeding response now.After refusing to eat for two and a half months, Extrovert the wandering garter snake is eating again. With her usual ferocity — viz., a mouse dropped into her cage might hit the cage floor before she strikes. Might. I am happy to see that my worries were unfounded (snakes do go off their feed from time to time, after all: Nic the Everglades rat snake is doing so right now), and that this wizened old garter snake continues to carry on.
  2. Infertile bullsnake eggs, second clutchLucy the bullsnake laid another clutch of infertile eggs — a full dozen of them. In her water dish, so if they were fertile before, they certainly aren’t now. (And they almost certainly weren’t: misshapen and miscoloured right out of the vent.) While this isn’t the first time one of our snakes has double-clutched (Pretzel did it all the time), it’s the first time we’ve seen double-clutching when we’re pretty sure mating hasn’t occurred. (Her cagemate, as I have said on many occasions, is useless in that department.) Chalk this up to a good diet: since Nic has been off his feed himself, Lucy has been getting some of the leftovers. A well-fed female snake will often put the extra into egg production.
  3. ... and here's the other one.Because we have no willpower ...Baby garter snakes are our kryptonite, and also the cutest things in the universe, so when a friend said they had more red-sided garter snakes than they knew what to do with, well, we were weak, and picked up a couple. These were born last year — and you’ll be interested to know, the grandchildren of our original breeding pair, being the offspring of a male from the famous litter of 42. It’s good to have young garter snakes again — our youngest prior to this is nine years old.

Adventures in Snake Missexing

Rat snake eggs (infertile, dried out)

At one point, when both snakes were starting to outgrow their cages, we were considering putting Spencer, our Baird’s rat snake, and Snowflake, our leucistic Texas rat snake, into one large cage, on the principle that two snakes of the same sex and two relatively closely related species would do reasonably well together. (We have three other rat and corn snake cages set up like this, two with two males and one with two females.)

Well it’s a good thing we didn’t, because when we did the big cage cleaning this week we found five dried-out, infertile eggs in the Texas rat snake’s cage. So much for Snowflake being male. Had Spencer been sharing a cage with her, he would almost certainly have tried to mate with her, and the two species are close enough that the eggs might well have been fertile.

We got Spencer’s sex wrong initially as well. When he was much smaller he briefly shared a cage with Snowflake’s mother, thinking they were both female; I separated them as soon as I saw him begin courtship behaviour.

And when I think about it, we — and the people who sexed snakes for us — have gotten the sex of our snakes wrong a hilarious number of times. The anerythristic motley corn snake we named “Little Guy” who grew up to be neither. The pair of speckled kingsnakes who tried to eat one another when put together for breeding; the “male” later coming down with egg binding. The red milk snakes, sold as a pair, who turned out to be two females. The checkered garter snakes, sold as two females, who turned out to be a male and a female.

Really, we suck at this. It’s a good thing we’re not trying to breed any more: it would all end in tears.

Snake vs. Snake: Copperheads in Atlanta


I have already written about the inadvisability of releasing snakes as rodent control, but releasing snakes as snake control is a new one even to me. In Slate, Holly Allen writes about her Atlanta neighbours releasing black rat snakes and kingsnakes to deal with an apparent outbreak of copperheads — the rat snakes to crowd the copperheads out, the kingsnakes to, well, eat them. As Allen (correctly) points out, releasing snakes is a super bad idea, for the usual reasons: translocated snakes have a poor survival rate and have a negative impact on local snake populations (and not just the copperheads). Leaving the copperheads alone is, as usual, the best thing you can do. Via

Are Water Snakes Invading California?

Two species of water snake have apparently been introduced to California. A new study published in PLOS ONE assesses the risk to native habitats and wildlife by identifying local habitat that would be suitable for the invasive species.

Water snakes are mainly found in the eastern half of North America: they come no further west than the eastern parts of Colorado and New Mexico. On the west coast their ecological niche is filled by large, aquatic garter snake species like the Sierra, giant and two-striped garter snakes (water snakes themselves can functionally be seen as large, aquatic garter snakes: fewer stripes, more attitude).

So how did water snakes establish themselves in California? The researchers attribute it to the release of captured pets. I’ve kept both of the species in question — northern (Nerodia sipedon) and banded (N. fasciata) water snakes — but water snakes are not all that popular among snake keepers. I’m amazed that enough snakes were kept in California that a sufficient fraction were able to escape or be released, and a sufficient fraction of that fraction were able to survive long enough to reproduce. Not that I’m saying it’s impossible, or even unlikely — if nothing else, water snakes are seriously r-selected, and can really pump out the babies — I’m just boggled by it.

Montreal Reptile Expo

Montreal Reptile Expo

Dropped in on the Montreal Reptile Expo yesterday — it was held at the Holiday Inn in Pointe-Claire, just off Autoroute 40, so not at all hard to get to. Stocked up the rodent supply, had a look around. It’s a small show compared to CRBE, but to give you an idea of just how much the hobby-slash-industry has grown, the Toronto reptile shows were about this big fifteen years ago. Still lots and lots (and lots) of ball pythons around, though the word is that fad has peaked: these things tend to ebb and flow as breeders chase the latest hot thing. A lot of boa constrictors and geckos, too, plus plenty of arachnids.

Photos? Of course! Here.

Bullsnake Eggs and Other News

Bullsnake eggs

Oh hello, look what Lucy the bullsnake left us this afternoon: eight little bullsnake eggs. Of course, they’re probably infertile: Lucy has laid infertile eggs many times before. We don’t hibernate the snakes to increase their fertility, and Lucy’s male cagemate, Boo, has never shown any interest in mating. Or at least we’ve never caught them at it (and I think we would have).

We’re sticking the eggs in the incubator anyway, at least for a few days, just in case: as you can see from the above photo, one of those eggs is whiter, larger and plumper than the others, so I can’t guarantee its infertility with metaphysical certitude. It’ll become apparent within a couple of weeks whether it is or isn’t, though. (This too is not new.)

In other snake news, Extrovert the wandering garter snake is off her feed, which for her is worrying. It’s been five weeks since she last ate, which in itself isn’t a problem, but she’s always had a ferocious appetite. Not only that: she’s been turning down earthworms, which is bacon to garter snakes. She’s 15 years old, which is a preposterous age for a garter snake, so it may well be her turn. (She can’t be pregnant: her mate died in 2003.)

On the other hand, Pretzel the corn snake has, as of last week, been with us for 15 years. She’s almost certainly older than that, since she wasn’t a baby when I got her, and she shows no sign of slowing down. At least, when she shows herself at all: she’s always been the most reclusive of our corn snakes.

Narcisse Snake Dens

Narcisse Snake Dens

While I was in Winnipeg earlier this month, I had the opportunity to pay a visit to the Narcisse Snake Dens during the spring emergence of their Red-sided Garter Snake population. (As one does.) Photos from my pilgrimage are up on Flickr, and I just posted an article about the visit to

Therapy Snakes Redux

Another data point in support of the idea of therapy snakes: CBC News reports on a couple of rescued Burmese pythons that have been put to work by Nova’s Ark, a zoo just north of Whitby, Ontario that focuses on special-needs children.

(Anyone else notice the reporter making the distinction between Burmese and rock pythons? That’s very interesting.)

Previously: Therapy Snakes.

Tracks and Shadows

Book cover: Tracks and Shadows Field biologists’ memoirs can often be a hit-or-miss affair, but Harry W. Greene’s Tracks and Shadows: Field Biology as Art is definitely more hit than miss, precisely because it is much more than a memoir.

Greene, who writes far too well for a biologist, is the author of the highly lauded Snakes: The Evolution of Mystery in Nature (1997). That book combined science, photography and personal experience in a lyrical and literate fashion, and may well have been the only snake book to win a literary award.

In Tracks and Shadows, the mix is more personal. In tracing the origins of his own career, parallelling it with that of Henry S. Fitch (1909-2009), a major figure in herpetology, Greene ably sketches out the why of fieldwork. Too many stories deal with the travel and the chase but elide the purpose of going out into the field to collect snakes; Greene shows us the science.

It’s a personal viewpoint, but this is not an autobiography; little of Greene’s personal life is mentioned past graduate school. There is plenty to indicate why a former mortician’s assistant and army medic became a herpetologist, less that reveals how he writes as well as he does. The scholar fades into the background of his own work: present as a field biologist in the context of a discourse on field biology.

As for that work, Greene is a snake ethologist: his research focuses on snake behaviour — why snakes behave the way they do, from hunting to defence to reproduction. The best parts of the books are the discoveries: his dissertation showing that primitive snakes all constrict in the same fashion, implying that constriction as a tactic is ancient; the discovery that night snakes predate on diurnal prey during the day; the evidence of parental and social behaviour in black-tailed rattlesnakes. The idea that there is more going on in those little serpentine heads than we expected is frankly quite exciting. Greene’s elegant writing cannot help but make that excitement infectious.

Tracks and Shadows: Field Biology as Art
by Harry W. Greene
University of California Press, October 2013
Buy at Amazon (Kindle) | publisher’s page | Goodreads | LibraryThing

A Snake Science Roundup

  1. Yellow-bellied sea snakes are pelagic: they spend their entire lives at sea — where, it turns out, they get awfully dehydrated. Instead of drinking seawater and excreting the salt, they drink rainwater that accumulates on the surface of the ocean, from so-called “freshwater lenses.” This means they mainly drink during the wet season and get awfully thirsty during drought; prolonged drought (yes, at sea: no rain) could be the reason behind the decline in some sea snake populations. Abstract.
  2. There is evidence that Burmese pythons have a homing ability: invasive pythons in Florida released 21 to 36 kilometres from their point of capture made their way back to their home ranges; some got to within 5 km of the capture site. Abstract.
  3. And here’s everything you wanted to know about the fact that snakes have two penises. (Lizards do too, but so what?)

The Snake Charmer

Book cover: The Snake Charmer Herpetologist Joe Slowinski died on September 12, 2001, in the forests of northern Burma, approximately thirty hours after he had been bitten by a many-banded krait. He was only 38. The Snake Charmer by Jamie James is both a biography of Slowinski and an account of the expedition that cost him his life.

The biography, drawing on family interviews and personal papers, takes up the first two thirds of the book. It reveals a type of character rather familiar to those of us who muck about with snakes: fearless, reckless (he was bitten numerous times) and just a little feral, absolutely fixated on the subject matter, and dripping, perhaps, with a wee bit too much testosterone. A difficult personality who nonetheless engendered fierce loyalty. But Slowinski was more than just Steve Irwin with a Ph.D.: he was stone-cold brilliant, a major contributor to the field of phylogenetics, and in particular to the systematics of elapid snakes — a point that James makes clear, if not at length. (Can’t say I blame him.) The final third reads like a feature article in Outside (and one was written about the incident, by another author), cataloguing the mishaps and bureaucratic nightmares involved in going deep into a restricted area of a country run by a deeply corrupt and paranoid regime, and the heroic attempts to keep him alive once the krait envenomated him while his support networks stateside were dealing with 9/11.

Where The Snake Charmer shines is in its portrayal of Slowinski himself; for all his reckless behaviour, he was not necessarily much for introspection. James has had to do his homework. I would very much have liked to see a bibliography, though, as in several James mentions publications that I wanted to look up for myself. In terms of the herpetology, for someone who is not necessarily well-versed in it James does a creditable job, though it’s clear he’s drawing on secondary sources for his material on snakes, and he makes a couple of minor errors that a herp-aware copyeditor (hi there) would have caught. But I’ve seen much worse. All in all an interesting read.

The Snake Charmer: A Life and Death in Pursuit of Knowledge
by Jamie James
Hyperion, June 2008
Buy at Amazon (Kindle) | author’s page | publisher’s page | Goodreads | LibraryThing

Snake Handling and Freedom of Religion

More on snake handling and religious liberty in the wake of Pastor Coots’s death by snakebite. Snake handling (in the religious sense) is usually banned where it’s practised: is that ban an unconstitutional restriction on religious freedom? Should people be able to put themselves at risk for reasons of faith? Peter Lawler, writing at First Things, and Michael Sean Winters, writing for the National Catholic Reporter, explore whether freedom of religion encompasses snake handling. Via Andrew Sullivan.

Reality Show Snake Handler Dies

Another high-profile snake handling preacher has died from snakebite. But this time there’s a twist: he had a reality show. Kentucky pastor Jamie Coots was one of the co-stars of Snake Salvation, a series on the National Geographic Channel. He was bitten on the hand by a rattlesnake last Saturday, and died after refusing medical treatment, as one does when one is a member of a snake-handling church. News coverage: AP, BBC News, CNN, WBIR TV.

Previously: “Praise the Lord and Pass the Rattlesnakes.”

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