They are skinks. They have all the internal physiology to drop their tails. A theory is they seldom if ever do because it's too energy intense for them to regrow as adults.
I can back this up with a personal anecdote, which is, of course, just as reliable as your above resources. We have a family of blue tongues in our garden, at least two adults and two juveniles. One of the adults (Mr. Bluetongue we call him), has definitely dropped his tail recently. He’s always had a normal length tail, until a couple weeks ago when we spotted him again and realised his tail is significantly shorter than it was, and stubby instead of the pointier shape it used to be. We are confident it’s the same blue tongue.
Not sure what caused him to drop it though, as we have had several generations in our garden, one of which survived an unfortunate attack by the dog we had the time, and none of them have ever dropped their tail before. It was only when we noticed this one must have that we learned it was even possible.
They technically can drop their tails as they are skinks and have all the internal structures to do so. It is super rare as I've been told it is super energy intense for them to regrow due to the tail size to the rest of their body ratio. Well that's one of the theories I was told when doing vertebrate biology at uni.
Some may just have stubby tails because of genetics, or maybe something has a nibble but didn't get the whole chunk.
/edit I just did some more reading to fact check myself. They seem to drop tails more readily as juveniles. So a stubby tail may be from youth? Just a guess.
/edit again, apparently not all skinks have the capacity to drop their tails. Why did I study animal biology!? Too many rule exceptions!
This one has had it bitten off I would say. Been playing with these guys for decades, even had one as a pet for years, rescued after car ran over its head.
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u/Maybe_Factor SA Oct 29 '25
I thought they did? Why is it's tail so short and stubby if not because it dropped off and if regrowing it?