There’s a new arrival at the zoo. I wanted to blog about it sooner, but I couldn’t. I’ll explain in just a bit. You remember Short Stack, the pancake tortoise that hatched in February?
The zoo has two pairs of pancake tortoises. Both laid eggs this winter that were intact and able to be incubated. This species is apparently a little tricky to incubate, and there can be as much as 40 days’ variation in hatch-times, unlike mammal gestation which can often be narrowed down to a two day window. A couple of weeks ago, Short Stack was joined by our second pancake hatching.
Each morning, keepers check the eggs in the incubator for signs if hatching, also known as pipping. The assistant curator knows how much I love this species, so he sent me an email to let me know the little critter was making its way into the world. I missed his email. Because I was already at the zoo. I got pictures. Crazy pictures.
Remember this turtle from last year?
And how after a few days it looked like this?
I thought all flat shelled tortoises and turtles developed in the egg the same way, with the sides folded down. Not Pancake tortoises! They actually develop rolled front to back. Look at how the baby flattens out over a few days’ time.
The reason it has taken so long to blog about this guy is because I don’t write about them until they have been accessioned (added) into the collection. And they can’t be accessioned without complete measurements of their shell. It’s hard to measure something that has been folded up like origami. It normally takes a couple of days for a tortoise to unfold completely. It took this guy about a week before it was flat enough to measure!
And here he is about two weeks after hatching, looking all ironed out. Finally.
I call him Squashy.
*** Nancy over at Not Quite Old asked why tortoises have a belly button at all. It was such a good question that I thought I’d answer it for those who are new to reptiles. Animals that develop in an egg are fed during their incubation by their yolk. They are attached to that yolk by an umbilical cord. After they emerge from the egg, the umbilicus closes. Sometimes that process takes a few days, sometimes traces can be seen a year later, but at that point it is nothing more than a mark on the shell.