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A Shaky Case for Wobbly Snakes

The “spider” morph is a popular variant of the ball python (Python regius) (Photo Credit:

The spider ball python is an exquisitely beautiful snake. Its cream-colored body is splattered with dark veins in the style of a Jackson Pollock painting. A fractal crown adorns its head, shaded with a subtle gradient of browns and blacks. The end of its tail curls into a distinct “C” shape as if to show its owner’s demure character. 

After its introduction by breeder Kevin McKurley in 1999, the spider ball exploded in popularity and remains one of the most in-demand pythons. Virtually every snake breeder sells at least one spider variant with many offering their own hybrids. Many in the reptile community celebrate the spider ball, not just for its contribution to the hobby, but also their livelihoods. 

So why do so many people want to ban it?.

In 2018, the International Herpetological Society (IHS) prohibited the sale of spider ball pythons in their shows. The news sent shockwaves throughout the reptile-keeping world. Heated arguments both for and against the decision flooded online forums, reptile magazines, and YouTube videos. As the controversy inflated in size, it spilled out of the insular world of snake husbandry and into the general public. Petitions to outlaw the breeding of spider balls appeared left and right, as did response articles to those petitions. Many snake veterans saw this as an assault on their hobby from outsiders, and many outsiders were appalled by the culture defending spider ball breeding.

The controversy stems from a single issue. A single gene, in fact. It turns out that the genetic mutation responsible for the trademark spider patterning has unintended neurological consequences. Spider ball pythons are born with a central nervous system disorder that causes their head to tremble, known in the reptile-keeping world as the “spider wobble.” The severity of the spider wobble varies greatly between each snake. Some spider balls struggle to feed themselves because of their lack of motor control, while others wobble so imperceptibly that their owners aren’t even aware of the condition. What is for certain is that the spider pattern and wobble are inexorably linked. There is no way to “cure” the spider wobble without removing what made the variant so beloved in the first place.

The spider is only one of hundreds of ball python “morphs”—artificially bred variants of a single python species, Python regius, with notable color or pattern qualities. Unlike dogs or cats, pythons aren’t particularly interactive pets. Their primary draw is their aesthetic appeal, the endless combinations of stripes, spots, chocolate browns and banana yellows that make up each snake’s appearance. The most desirable and rare “designer python” morphs can fetch anywhere from a few hundred to tens of thousands of dollars. 

In fact, a sizable number of spider ball fans consider the “cute” spider wobble to be one of their best features.

The argument against the continued breeding of spider ball pythons is obvious. This is clearly a case of putting an animal’s looks before their quality of life. Animal welfare advocates have criticized the reptile breeding community for ignoring the spider ball’s suffering to continue selling these morphs at a high profit. Indeed, the IHS ban has done little to stop the demand for spiders from online vendors and non-IHS reptile shows. The breeding of these neurologically-impaired snakes is still perfectly legal in the United States. 

Even more alarming is the fact that many of these sellers don’t disclose the spider wobble condition to customers. Ball pythons are extremely popular snakes, routinely advertised as a perfect beginner’s pet. Given how ubiquitous the morph has become, it’s very possible that an unsuspecting customer might purchase a spider ball without understanding the extra care it requires.

For a seemingly open-and-shut case, snake breeders are very ambivalent. A survey of both breeders and scientists specializing in animal welfare found startlingly differing opinions on the impact of the spider wobble. Whereas breeders generally reported that spider ball pythons enjoyed a comparable quality of life to normal ball pythons, 89% of welfare scientist respondents believed that the spider wobble would pose “moderate to severe” effects on the animal’s wellbeing. Perhaps most tellingly, one of the breeders reported that even their most severely affected spider ball pythons are able to breed and “lay good eggs.”

Proponents of the spider ball python have put forth several arguments to defend these breeding practices. Of course, spider balls have great ornamental value. They’re also a major part of many people’s businesses. But one point these spider ball defenders bring up is worth discussing, not just because there’s no clear response to it, but because it has implications for much more than the snake keeping microcosm: what is a healthy animal?

All python morphs are “genetic deformities.” Every human-picked color and pattern has consequences for the animal’s health, no matter how small. Spider balls seem to represent a plain case of sacrificing an animal’s quality of life for selfish reasons. But what about albino pythons? Albinism is bred for aesthetic value, but it might also cause the animal’s eyes to be slightly more sensitive to bright lights. The actual effect of this sensitivity might be tiny, but this is still an example of putting an animal’s beauty before its wellbeing. 

Genetics is infinitely subtle. A single mutation on a gene that codes for an animal’s appearance can have a cascade effect on hundreds of other traits, interacting with other genes involved in everything from brain development to reproductive health. When humans create a new breed with a certain trait, its descendants inherit all of these adjustments. Not only does this make evaluating each morph far more difficult, it also raises the question of what should be used to measure them. There’s no consensus on what “morph zero”—the standard set of phenotypes for ball pythons—is supposed to look like.

This dilemma is best illustrated by a more popular choice of pet. The American Kennel Club recognizes 190 dog breeds alone. These breeds are divided into seven categories depending on their original job, including sporting dogs and scent hounds. Some dogs are considered more “unhealthy” than others for a variety of factors. The most notorious case is the English Bulldog, the poster child of genetic deformity. It’s prone to overheating, struggles to breed through its snout flaps, and fails to breed on its own. Combined with an ever-shrinking gene pool, the bulldog has long attracted both love and scorn. Like the spider ball python, animal rights advocates have petitioned for the restriction of bulldog breeding, sometimes successfully.

But also consider breeds that are generally considered healthy, like Pembroke Welsh Corgi. Corgis live nearly twice as long as bulldogs, but they also suffer from a variety of hip and spine issues due to their long bodies and short legs. If you believe that bulldog breeding is unacceptable, do corgis also cross the line?

The issue here is that we cannot compare bulldogs and corgis to a “default” dog, a hypothetical standard-bearer to which we measure the net effects of all the genetic alterations that go into the makeup of a breed. There is no universal threshold for when breed characteristics sufficiently interfere with the animal’s health to make their continued existence unethical. 

These examples are made all the more complicated by the lack of absolutes when it comes to life or death. Neither bulldogs nor spider balls have a lethal gene—some mutation that will eventually end their life. They may certainly succumb to diseases common to their breed, and in many cases their phenotypic changes render them helpless outside the care of humans. This raises yet another question of whether it is ethical to create animals that depend on humans for survival.

One often-suggested moral measure is to consider the breeder’s trait-selecting philosophy. Maybe it’s not about how much a genetic change interferes with an animal’s life, but rather how the change was picked. If the change is meant to improve the animal’s health and happiness, it’s acceptable. If it’s only meant to make the animal more appealing for humans, we may object to it. Indeed, this is a guiding principle for many recent developments in canine breeding, such as the efforts to revive pre-inbreeding variants of bulldog with less face flaps and leaner frames.  Under this lens, both severe and mild cases of genetic impairment, spider ball and albino pythons alike, represent an abuse of breeding power.

This proposal opens its own can of worms. For one, there’s the question of what falls under the “appealing for humans” genetic alterations. Certainly this includes cases where animals are bred for their appearance, but what about livestock? The domestic chicken is an avian monstrosity. Compared to its junglefowl ancestor, it lays an absurd number of eggs year-round and grows inflated breasts for meat. Wild sheep are able to shed their wool every year, but domestic sheep continue to cling onto their coats until a human shears it off. Not doing so poses a serious threat to the sheep’s health. These seem to represent instances where animals serve a far more important purpose to humans than ornamental value, but they are still genetically modified at their expense. 

Returning back to snakes, it seems as though what truly disturbs us about spider ball pythons is how easily their breeders seem to disregard the responsibility of animal life. The “designer python” label isn’t just about how dazzling these morphs look. It’s describing a pervasive attitude towards the creation and sale of snakes as fashion items. It’s true that snakes are nowhere near as friendly as dogs—for many owners, the most interaction they’ll have with their python is a monthly mouse feeding. It’s also true that ball pythons come in many beautiful breeds. They live for quite a long time, are easy to care for and easy to trade. This naturally encourages snake enthusiasts to collect ball pythons like paintings, prized for their looks, not companionship.

So when breeders continue to produce spider ball pythons despite the risks to their neurological stability, it reminds us that snakes are, first and foremost, a business. As long as spider balls are a hot item, the market has no reason to refuse demand. When breeders argue that all morphs are, in fact, man-made abnormalities just like the spider ball python, they’re absolutely right. The spider ball is just one of countless genetic permutations, each with its own set of benefits and risks. It’s a single cage in a rack of animals sculpted generation after generation to maximize consumer appeal.

And maybe we shouldn’t be okay with that. Although the IHS ban made a great symbolic statement, it hardly changed the status quo in the reptile-keeping world. Spider ball pythons are, if anything, more common and cheaper than ever before. Without legislative restrictions, it’s unlikely that consumer demand will go anywhere anytime soon. 

But which would we ban first, bulldogs or spider balls?



  1. Admin. “Pembroke Welsh Corgi Dog Breed Information.” American Kennel Club, 6 Nov. 2017,
  2. Clauer, Phillip. “History of the Chicken.” Penn State Extension, 9 Mar. 2021,,jungle%20fowl%20from%20Southeast%20Asia.&text=The%20sport%20of%20cockfighting%20had,of%20fowl%20throughout%20the%20world.
  3. “Dog Breeds – Types Of Dogs.” American Kennel Club,
  4. Handwerk, Brian. “Bulldogs Are Dangerously Unhealthy, But There May Not Be Enough Diversity in Their Genes to Save Them.”, Smithsonian Institution, 29 July 2016,
  5. “If the Spider Ball Python Is Being Shunned the World over Why Is the Bumblebee Ball Python so Popular?” XYZReptiles,
  6. Jackson, Neville, et al. “Evolution of the Sheep Coat: the Impact of Domestication on Its Structure and Development.” Genetics Research, vol. 102, 2020, doi:10.1017/s0016672320000063.
  7. Lauraihsadmin. “IMPORTANT NOTICE – BANNED MORPHS.” International Herpetelogical Society, 20 June 2020,
  8. Rose, Mark P., and David L. Williams. “Neurological Dysfunction in a Ball Python (Python Regius) Colour Morph and Implications for Welfare.” Journal of Exotic Pet Medicine, vol. 23, no. 3, 2014, pp. 234–239., doi:10.1053/j.jepm.2014.06.002.


  1. Chan Chan

    Here are the false/inaccurate statements in this articles:
    1) spider mutation gene in the article mentioned is not an expensive gene people seek in the Royal python hobby. There are many are mutations that have no head wobble or any health imperfection and are many time more expensive in price.
    2) the statement about spider gene breeders are sketchy and not disclosing the head wobble issue to the buyers. All breeders, which i have met and dealt with, discloses spider wobble or any health issue before selling them. The breeders always make sure the buyer can take care of the pet python for sale. I have 3 pet royal pythons with spider gene and 2 of them have no wobble and 1 has slight wobble. All 3 sellers showed me videos of the snake eating and answered all my questions before the sale. All 3 of my royal pythons with spider gene are eating and living well. They are thriving and growing healthy.

    who are we to decide what others can breed or cannot breed? Some of my friends’ kids have to wear prescription eye glasses at young age as their parents also wear thick eye glasses. Are they not supposed to have kids because the parents don’t have 20/20 vision? How about little people? Can little people have children and family? Are these not also gene mutations?

    Please get the research and fact right before publishing the article. I am sure there might be breeders who do not care about animals and only care about $$$. Almost all breeders i have met in the hobby are people who loves the animals.

    • Peter Nam Peter Nam

      1. Yes, spider mutations are not a terribly expensive or rare morph. As I noted in my article, there are many “designer morphs” that can run you several thousands of dollars, many times the price of the spider ball. The popularity of spider balls encouraged breeders to produce more of these snakes, which increased the supply and drove the price down. It is this ubiquity that is concerning, not the price; we should consider how easy it could be for an inexperienced snake owner to buy a spider ball with no knowledge of that morph’s neurological history.

      2. All spider morphs do have the “wobble” condition. It’s tied to the gene mutation that gives spider balls their body pattern. I pointed out in my article, however: “some spider balls struggle to feed themselves because of their lack of motor control, while others wobble so imperceptibly that their owners aren’t even aware of the condition.” There are many spider morphs that seem to enjoy (at least to our eyes) no worse a quality of life than wild-type ball pythons. These phenotypic subtleties from snake to snake are part of what makes this debate so complicated and fascinating. It is also true that there are plenty of reputable sellers that will disclose any health issues with their snakes. But if the commenter was told by their seller that some spider balls have no wobble, they have, in fact, received misleading information.

      3. Occasionally in this debate, you’ll hear someone bring up a slippery-slope argument: if we stop breeding spider morphs because they have a genetic defect, what’s to stop us from banning people with hereditary diseases from having children? I hope it is clear why this is a poor analogy. We don’t breed snakes because our snakes want to raise a family. We breed snakes because we want more snakes. Nobody on either side of this controversy is fighting for a snake’s right to have children.

      • David David

        Did it not occur to you that us humans are also not bred for the sake of family, but we are actually livestock that the mosquitoes are breeding as a food source just because they want a variety of flavors to choose from.

      • Nic Nic

        I would like to know where you learned that ALL spiders have wobble.
        Also, there are several other genes that can cause it. For some reason people only know of spider.

  2. Kyle Frost Kyle Frost

    What a disappointing article. I would have suspected that the author was being intentionally disingenuous, had they not also demonstrated their poor understanding of simple monogenic trait heritability (the Spider gene in Ball Pythons is an incomplete dominant trait, not a hybrid or a ‘breed’).

    I breed Ball Pythons, but haven’t kept Spider Ball Pythons and don’t personally feel that it’s ethical to produce Spider ball pythons, or any genetic trait with any known deleterious health association. I have been breeding ball pythons for 16 years and in that time have intently watched how the ‘industry’ handles these situations like the spider gene. While there are certainly a handful of breeders who are hopelessly in love with the spider gene, MOST breeders who used to breed them have phased them out of their projects. The ratio of Ball Pythons produced today that have the spider gene are less than since it’s inception, and declining.

    Ball Python breeders, enthusiasts, and pet owners generally don’t want animals that are suffering unnecessarily(although you seem to suggest that anyone who dedicates their life to these animals must be greedy and unscrupulous animal haters). However, as a result of the principals of most owners, today, a ball python with the spider gene is worth LESS than one without.

    There are a few other unrelated examples of genes with health
    consequences which have been all but been bred out of the hobby entirely. Spider is unique for it’s timing. It was one of the first genetic traits that appeared in ball pythons- a bold pattern mutation unlike anything else, and could be inherited in the first generation of progeny. It was also the first gene with a neurological problem associated with it.

    The industry has learned a lot from the spider gene, and although it’s hard to put the toothpaste entirely back in the tube, the takeaway is that most people don’t want unhealthy animals, and those people decide the market.

    I have to wonder if your venom towards Ball Python owners is rooted in some anthropomorphic idea of how people should interact with their snakes when you say that they’re “prized for their looks, not companionship.” Do you think that people shouldn’t breed ball pythons? Should pet ball pythons, instead be taken from the wild? Or should ball pythons not be allowed as pets at all by that logic? I could at least take that dialogue as more sincere than this misguided and misinformed spider gene article.

  3. Lucas Gray Lucas Gray

    I agree that spiders shouldn’t be produced, since their looks do seem to come before their health in some cases, and it’s impossible to tell when a badly affected snake will be produced (snakes with zero wobble can and have produced offspring with severe wobbles). I do not own any spider ball pythons and I do not ever plan to. However, there is a huge piece of the puzzle missing here: spider isn’t the only gene that has these issues. Everywhere you look, there people raging about how inhumane the breeding of spider ball pythons is, how it should be banned, how those breeders are sick and twisted for putting money before their animals, etc etc. But where are the people advocating against the breeding of other wobblers? The HGWs, the Woma morph, Champagne (the Super form of which is also lethal when produced), super spotnose/Powerball, super sable, and any wobbler x wobbler pairing (which typically results in lethal combinations or babies affected by severe wobbles).

    Furthermore, where are the articles and petitions to stop the breeding of super cinnamon and super black pastels? Those are both very popular morphs which are very prone to kinking of the spine as well as duckbilling but nobody ever tries to advocate for them, do they? What about the caramels who are also prone to severe kinking?

    I’m sure there may be some articles out there discussing the aforementioned morphs, but i’ve certainly never seen anything even close to the uproar about spider.

    It seems to me that everyone simply wants to demonize the spider gene. They want to write about something they know is controversial and will get views and traction in the media since it’s already heavily talked about. And since they advocated against the breeding of that morph, any time they’re successful in getting it banned somewhere, they can cross their arms and say “Hah serves them right, i helped solved the issue!” and feel good about themselves like some influencer who just filmed a homeless man.

    People so desperately want to take a moral high ground without knowing what they’re talking about, and it really shows how shallow a lot of people are.

    And because of that we very likely will have people who know nothing about ball pythons go to an expo, look at one that has HGW or Champagne or some other problematic gene in it, say “oh wow it’s so pretty, thank god it doesnt have spider in it!”, buy it, then have a wobbler without knowing it. Oftentimes, yes responsible breeders do disclose whether the snake is a wobbler or not, but I have heard of instances (I may be wrong, since I dont have personal experience with wobblers, this is just what I’ve heard) that a bp can have no wobble at birth, but develop one as it ages, so that opens up a whole new can of worms.

    Not to mention the fact that deformities, kinking, and wobbles can, have, and do occur in every morph (yes EVERY morph) albeit at a much lower rate than genes like spider and co. This fact counters the point made in the article of “if we remove spider from the equation then no more wobble :)”.

    I’m not saying this to justify spider. As I said, I do not support wobble morphs and the like. I’m saying this because I’m still new in this hobby (got my first bp three years ago), but the amount of misinformation out there in the media is absolutely abhorrent. If you’re going to write an article about spider, include the other problematic morphs. Or better yet, do more articles dedicated to each problematic morph. Inform the people. Dont just jump on the bandwagon for views

    • David David

      You just gave me a FABULOUS idea!!! I can finally get my tiktok to go viral if i did a video on why breeders need to breed lots of spiders… And hashtag #ballpythons

    • Nic Nic

      Well said. I think it’s unethical to attempt to irradicate a line of animals who imo are not “suffering”. When breeding animals, MANY things can pop up. This is natural. I own champagnes and have zero wobble. Who is to tell me they are faulty?

  4. David David

    Aside from the grammatical errors, I think your article is a fabulous piece of writing. I like how you express both sides of the argument without making it clear which opinion you agree with. I like how your bringing in of livestock as an analogy causes thought provocation, without making it clear whether or not to, “ban all livestock,” or “justify more acceptance.” It is also a well written perspective for inquisitive outsiders that don’t want to get confused by an abundance of technical terms. It is certainly a magazine worthy article (after minor editing). Good job;)

    • Nic Nic

      I liked this aspect as well

  5. Nic Nic

    Excuse me… but who are YOU to tell the world how the snake community feels about their snakes? You literally compared it to “collecting paintings”. How dare you make assumptions that breeders and keepers do not love and cherish their animals as ANY other animal owner does! You are painting a terrible picture about something you know nothing of, nor have ever experienced.
    These animals bring loads of joy to their keepers/breeders and you write as if it is simply a product.
    You are wrong about the spider, as it has deminished in the breeding world and are right to compare it to dogs.
    But to imply snake keepers do not respect or enjoy the “companionship” of their snakes is a figment of your imagination. Nothing makes them happier. Those who see them as cash-creating “objects” do not last.

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