Crested Gecko Myths

I've listed below some widespread myths and misnomers that I have seen swirling around on the internet and when I talk to my friends and customers. I think what's most alarming to me is that this stuff is being treated as common knowledge, and people - even myself at times - are actually picked on for not knowing better.

I don't have the time or desire to correct misinformation every time I see it, as people who pass along misinformation are usually there to build a customer base and they really don't like being told they're wrong, particularly in a public setting, so they'll never concede the fact they haven't actually experienced what they're describing can happen.  That being the case, I figured this page would be a good idea for helping new and not-so-new crested gecko keepers sort out the fact from fiction.

The point is to dispel any potentially harmful misinformation, so that our geckos don't needlessly suffer, and also so that keepers and breeders can feel confident doing what works for them, without being publicly shamed for it. 

My goal here isn't to embarrass or condemn anyone.  I don't keep track of who says what, so I'm certainly not going to name any names here - although I do serve my 30-year-old self a slice of humble pie on the topic of feeding mealworms.  That's how I learned that it's really best not to pass along info unless you know for a fact that it's accurate, and you have the actual experience to make a definitive statement.

The next time you see someone spreading one of the below myths, you can just ignore them. And if they call you out for not following protocol in some way, you can direct them here to read my take, and save yourself the pain of being attacked for doing things differently than they do.

Myth #1 - "Cohabbing" is dangerous and a bad idea. And you're a bad keeper for doing it!

This is total nonsense and very widespread - this topic gets its own page HERE.

Myth #2 - Crested Geckos won't, or shouldn't, eat mealworms.

This is a myth that started in the leopard gecko world, but applies to crested geckos just the same. This one is actually really interesting, and I was really excited when I figured out what the problem/cause was, and that mealworms are a viable and convenient source of insects.

I actually played a role in this when I stated that mealworms left in the cage often went unnoticed by the geckos. It wasn't until years later that I decided to try putting mealworms in a dish, which I must say works well, but only once the geckos have figured out that mealworms are food.

So, the myth goes like this...

"Crested geckos shouldn't be fed mealworms because they have trouble digesting the exoskeleton (or "shell"), and they're not a very good food source anyway."

OK - First of all, mealworms are a fine food source, so get that out of your head. They are high in protein and relatively low in fat, even compared to crickets.

Secondly, leopard and crested geckos have a digestive enzyme in their stomachs called chitinase which is there specifically to digest chitin - the very material that the exoskeleton or shell is made from.

So where or why did this myth start?
Most people offer mealworms in a dish to keep them from burrowing under the substrate or paper. For a gecko that's used to hunting for insects, a dish full of mealworms is literally the proverbial "fish in a barrel" scenario. This can be problematic for a gecko that's used to having to hunt and work for it's insects. To a gecko that has never seen such a wonderful sight (a dish full of insect larvae that can't run away), they will try to eat as many as they can, effectively gorging themselves to the point of regurgitating. What they regurgitate typically resembles a little football shaped clump of undigested mealworms. It's easy to see how someone who didn't know any better could think this is because geckos can't digest mealworms, especially when that's what everyone on the internet has been telling them.

I've seen this phenomenon over and over again when breeding leopard geckos and also with crested geckos. Fortunately, once your geckos start to see a dish full of mealworms as a normal thing and not a one-time opportunity to pig out, they will quickly learn not to do gorge themselves. The best thing you can do is to limit the number of mealworms you offer your gecko(s) at first. Once the gecko has gotten accustomed to seeing mealworms in a dish, it won't be as likely to go bonkers attempting to eat every last one of them.

Myth #3 - Males and females must be separated in the off-season.

This is a myth that started a long time ago. I'm not sure why the breeder who started it did so, but I believed it, and I separated my geckos every year for several years. I also passed this misinformation on for years, regretfully. As my collection grew, this process became more and more of a pain in the neck, and I decided that it made no sense to me. Who separates them in the wild?

So that was it - I decided to leave my breeders together all winter and see how it went. The geckos did fine. Contrary to the myth, males do not continually harass the females in the off-season. This is because males are attracted by the pheromones they detect on a female who is actively producing follicles and eggs. If the female isn't ready to be bred, she won't be producing the pheromones that makes the male want to breed with her.

Some breeders have told me they prefer to separate males every year, and that's fine - there's no harm that can come of that.

The next time someone tells you separation is necessary, ask them who separates the males from the females in the wild. :-)

Myth #4 - Crested Gecko morphs are random and are too complicated to predict what a pairing will produce.

This is completely untrue. Unless someone is talking about how an independent gene or trait is inherited, I wouldn't pay any attention to what they're saying because it's likely nonsense.  Most colors and traits in crested geckos are inherited in an allelic (genetic) fashion...either incomplete dominant or recessive, just like most ball python and leopard gecko morphs. The intensity of certain pigments (like Tangerine) and extreme forms of certain markings (like pinstripe) can be selectively bred for, but that also holds true with ball pythons and anything else.

Without getting too lengthy, the reason we get several different phenotypes or "morphs" from a single pairing is because there are multiple genes being inherited from each parent, all with separate 50/50 odds of being inherited. Even if there were only are 2 genes that make up an appearance (unlikely), you would still get up to 4 different phenotypes. If there are 3 genes then you get 8 possible phenotypes, with 4 genes you get 16 possible phenotypes, 5 genes you get 32 possible phenotypes. As you can see, odds can get long, and certain phenotypes or appearances will appear to the average breeder to be a random one-off appearance, when in reality they just hit on a 1-in-32 gecko from a pair that might only produce 12-16 eggs a year.

That's why we're breeding for "supers" in any trait where a super is possible. With the super form (or homozygous form) of a morph, you know that one copy of the gene/trait will be passed along to all of their offspring, and those pesky odds are removed from the equation for that particular gene/trait. If you have two supers in a pair, then you know the offspring will get one copy from both mom and dad, and therefore all offspring will be supers.

If you understand ball python morphs or leopard gecko morphs, this stuff is all pretty elementary - unfortunately a lot of crested gecko breeders have no experience with other species or morphs, and they tend to not only believe the misinformation they've been given, but pass it on to others as well.

The fact of the matter is that if you breed a pair of geckos repeatedly for enough years, you will absolutely see the same phenotypes (or combination of traits/colors) appear time and time again. Some will be relatively common from that pairing, and others will seem more sporadic - that's all because of genetic odds and how many genes are involved in that appearance. If there's a really cool appearance that you believe to be one of a kind, the chances are there are just a lot of genes involved and the odds are low. It may be a couple years until you produce another gecko of the same phenotype...but eventually you will.

When someone tells you crested gecko morphs are polygenic (or "polymorphic" if they really don't know what they're talking about!) and therefore cannot be figured out, you can safely assume they just don't understand genetics and they're using the term "polygenic" to infer that they're too complicated to understand.

This is a myth that has caused serious confusion in the crested gecko world, and I know for a fact it has caused other reptile people, like ball python and leopard gecko breeders, to steer clear of crested geckos. The next time someone tells you crested gecko morphs are different because they're polygenic, remind them that ball python and leopard gecko designer combos are all polygenic and a lot of us understand how they work just fine. ;-)

Myth #5 - The tails of crested geckos don't regenerate or "grow back".

This one isn't harmful to the hobby, and is just something I've put here for fun. Technically speaking, it isn't true that crested gecko tails don't regenerate, and I'll explain why.

When the tail is autotomized, or dropped, technically speaking, new tail tissue and bone does grow back. What grows back, though, is a very short nub-like tail, similar to that of certain species of knobtail geckos. Sometimes the knob-tail will grow back about 1/4" long and occasionally it will grow to about 1/2" long. Philippe de Vosjoli reported that the knob-tail is longer the younger a gecko is when the tail is dropped, but I've never tracked and measured them myself.

But WHY don't they just grow back like normal?
From my experience observing tens of thousands of geckos at various stages in their growth and development cycle, and seeing the movements they make when trying to evade capture (by me), it makes perfect sense that a tail would be a disadvantage for older geckos. The larger a gecko gets, the heavier the tail gets. Not only does the tail weight down the rear end of the gecko, giving it reduced range when jumping, the tail also seems to slow them down on the ground. Fresh hatchlings, however, move very differently. The tail and abdomen move together in a serpentine fashion, with the tail seeming to help propel the gecko forward. When navigating brush or vegetation, hatchlings will often use the "toe pad" on the end of their tail to hold onto things and steady themselves. As they get older, they tend to not do this as often.

As it is the case with frogs, where the tail of tadpoles will eventually shorten and disappear, I believe this tail phenomenon in crested geckos is an evolutionary adaptation, and I think it's actually pretty cool. :-)

Myth #6 - A lavender has to fire up lavender to be considered a lavender.

Above is Stripes, the founding sire of my entire Lavender project. This 2004 male was incredibly high-end for his time in terms of color, pattern, and structure. He has sired well over 1,000 offspring to date, so just imagine how many grandchildren that makes for. Stripes is a common ancestor to nearly all of my lavender crested geckos, and likely a common ancestor to the vast majority of lavenders on the market today. You might be surprised to learn what other Pinstripe & Quad Stripe projects Stripes has played a major role in, as well.

This is a gem of a myth that just came up in the past year or so, and is one of the most ridiculous things I've seen posted on Facebook concerning crested geckos in a long time. I was actually called out and attacked in a Facebook group for not knowing what a lavender is - by a handful of people who were most likely in pre-k or kindergarten back in 2004, which is when I personally coined the term lavender in the crested gecko world (and of course had to defend it). :-)

1. Their reasoning, flawed as it may be, is that we normally call geckos by the color they fire up.
That's a good observation and all, but that's not a steadfast rule and it never has been. We only mention "fired-up" colors on most because a lot of geckos are a bland color that we don't want to look at (or talk about) when they're at rest. For example, "red" sounds better than "pinkish greyish tan", and "orange" sounds better than "sawdust".

2. I've seen lavender geckos that don't fire up, and I've seen some that take on a purplish black hue, but I've never seen one that fires up to a color I would consider lavender - and I've seen plenty of geckos that people claimed to do so. What's going on here is some uninformed people are trying to apply a name to geckos that supposedly fire up to one specific shade of lavender - a subjective shade that they can't actually define. This makes no sense from a genetics/breeding standpoint, and only serves to confuse people even more about crested gecko morphs.

When a lavender & cream pinstripe gecko fires up black, I will call it a "lavender/black & cream pinstripe" to avoid confusion, but having said that, many lavenders won't actually start firing up until they're nearing sexual maturity. Even worse, some lavenders will only fire up on rare occasion, like when they're incredibly stressed (during shipping, etc.), so it can sometimes be tough to tell which shade of lavender you actually have.

Of course, the people propagating this myth probably haven't yet thought of any of that because they don't actually breed or sell lavenders - at least not in significant enough numbers to have gained an understanding of how it actually works.

3. The term lavender was coined by me (AC) in 2004 to describe the relaxed color of a lineage of geckos that are lavender-grey at rest, and fire up to dark grey or black. Of course, as is the case with everything new, I had to defend the lavender name to people online who had never seen one of my lavenders in person and were claiming that the camera flash is what caused the color. Fast forward a decade or so and I'm now being told only certain lavenders deserve to be called lavender. I guess it really never ends. :-)

The lavender project started with my Stripes line and later evolved into a huge, multi-lineage project that consists of over 150 breeders today. It wasn't until many years into the project that we started seeing specimens from this lineage that don't seem to fire up at all - ones that stay lavender (not to be confused with those that supposedly "fire up lavender").

4. As with reds or any other base color, lavender geckos come in varying shades. Some fire up darker than others, some show color when not fired up, and some just don't seem to fire up - and that's how every color works. That said, being darker or lighter doesn't make a color a different color, genetically speaking - and genetics are what dictate our breeding efforts. No amount of discussion on Facebook is going to change how this works. Morphs and colors work how they work, not how a group of novice gecko keepers on Facebook decides they should.

6. If someone insists that your lavender is not lavender because of how dark it fires up, it is safe to assume they don't have much, if any, actual experience developing a lineage of lavender geckos. In fact, I would probably go so far as to say they probably don't have a strong understanding of reptile morphs in general. In this case, it's my opinion that those people have no business telling you, or me, what a lavender is or isn't, and I would take anything they say with a grain of salt.

Generally speaking, people who argue online about crested gecko morph terminology are people who put far too much stock in what geckos are called, and not enough stock in what they look like or how a trait or color is reproduced. Any truly hard core gecko breeder knows better than to put too much stock in names, they understand how colors work, and they can usually tell what color they're looking at without having to be told.

In my personal experience, people who argue about morph names on the internet often fall into one of two categories - internet experts who have spent far more time posting online about geckos than actually working with or learning about them, and the unfortunate new keepers who have made the mistake of listening to the aforementioned internet experts.

I'm sure there are plenty more crested gecko myths out there, but this is all I've had a chance to rant about so far. If you have any suggestions, send me an email using the link at the bottom of the page, and I'll definitely take it into consideration.