Shell geometry

[TheLastGreen]

I have posted the shell before on a seperate thread, but I thought it would be intresting to make a thread of its own.
My tort Zvezda has an intresting shell patern
(Here she was soaking, she likes to relax and stretch her leg out)
She has a shell pattern of 5 4 5, instead of the usual 4 5 4 pattern.
She was hatched 5 years ago in Cullinan, a town in a semi bushveld area where things get extremely hot.
@zovick has suggested that the higher incubation temperatures could be the culprit.
Today I saw the pattern again, and thought it would be intresting to share!

 

[biochemnerd808]

I've always liked summetric extra scutes! Very pretty.

In my experience, both higher-than-usual and lower-than-usual temps can result in split scutes.
Now, my breeding experience is not with leopards, but I would imagine there would be some basic similarities. I normally incubate at 89°F but occasionally before adding a digital thermostat to the incubator, the temps have fluctuated up to 90 or even 91°F. In those cases, I almost always had a 1/10 splitty scute baby. I have also incubated some Russian tortoise eggs at lower temps of 82-84 °F for clients by special request because they wanted males. Both times, the babies hatched with extra scutes.

 

[TheLastGreen]

Very intresting! Do you perhaps have any images of those torts?
It's intriguing to think how the shell forms, does it fuse during incubation?
Someone like @Markw84 may know the process, he's posted an intresting thread where they study the production of a certain hormone which determines sex and the influence temperature has on it. Intresting to think that temps play such an important role during incubation for torts!

 

[biochemnerd808]

Very intresting! Do you perhaps have any images of those torts?
It's intriguing to think how the shell forms, does it fuse during incubation?
Someone like @Markw84 may know the process, he's posted an intresting thread where they study the production of a certain hormone which determines sex and the influence temperature has on it. Intresting to think that temps play such an important role during incubation for torts!

I have photos of every baby I've hatched, but the older ones are buried somewhere in an external hard drive.

The scutes (sections of the visible shell) develop during incubation, yes. They are made of keratin, and the lines/seams don't overlap with the seams in the bony plates underneath.

They must develop pretty early on... Because the few times where an egg died and the hatchling was large enough to discern shape, the tiny scutes on the shell were already visible in the fetus in the egg. One time, an egg died (turned black) and I opened it, and the fetus inside was the size of my finger nail. The scutes were already clearly visible, though kind of random on that one and one leg was shaped weirdly, I assume it didn't survive because of genetic or internal developmental anomaly.