Zig First, Then Zag.

This female Anolis carolinensis has a tail that is kinked in a zig-zag fashion, starting from what seems to be the proximal autotomization point and continuing distally along the tail. The kinks are permanent. Running the tail between one’s fingers fails to smooth out the zig-zags. Have any anoleologists out there seen this growth pattern before? Any idea what might cause it? Additional photos and an x-ray are after the jump.

Here is an x-ray image of the tail.

About Yoel Stuart

Yoel studies evolutionary ecology of Anolis lizards. He is a graduate student at Harvard University, in the Department of Organismic and Evolutionary Biology.
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9 Responses to Zig First, Then Zag.

  1. justinhenningsen says:

    I see that with some regularity, maybe in 5% of animals here in SC. I was told that it can result from a calcium deficiency, but I don’t have any evidence to back that up.

  2. Lisa McCune says:

    I’ve seen tails like that in captive (wildcaught) Japalura splendida, if that helps any…..

  3. thsanger says:

    While I find it peculiar to find this is nature, I have been told the same thing as Justin – calcium deficiency. I have observed this develop in multiple A. carolinensis after about one breeding season in captivity. Some photos I have found on the web of lizards with “metabolic bone disease” look strikingly similar to this, but I have never gone so far as to try having lizards in our colony diagnosed.

  4. geneva says:

    Interesting stuff, Yoel. I don’t recall seeing anything similar in our wild caught or lab reared A. distichus, but if what Justin heard is right we might not see it as we supplement calcium. Was that tail exactly like that when you found her, or has it gotten more or less pronounced in captivity?

  5. jerryhusak says:

    I have seen this several times in wild collared lizards (Crotaphytus collaris), and a few times in green anoles I’ve worked with in Louisiana .

  6. Yoel Stuart says:

    @Anthony: She was like that when we found her in the wild. There are a few more in our colony as well.

    @Justin/Thom/Anthony: The calcium deficiency seems a reasonable hypothesis except that a lot of the older lizards I’ve caught on my islands have visible calcium deposits behind their head. Unless that’s not calcium…

    @ All: Thanks for the comments! Perhaps the developmental folks can pursue this further!

  7. gabrielgartner@fas.harvard.edu says:

    This is extraordinarily common in captive lizards, particularly if you dig through the piles of lizards at one of the big importers like Strictly where wild caught lizards are often kept for some time without proper supplementation. I think in general it’s due to insufficient calcium, but also to too much phosphorous in the diet as well.

  8. Yoel Stuart says:

    An hatchling emerged from the egg today, laid from a female who was in captivity for about a week. It also had a kinked tail, suggesting a genetic component although maternal effects can’t be ruled out.

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