Hi everyone, I'm Dawn and I'm with the Academy's Nature Museum.
We're out here at the Collections Facility today.
I am going to feature some specimens in our herpetology collection.
So what is herpetology?
In our scientific collection for herpetology,
we feature reptiles and amphibians, and our collection has over 22,000 specimens
in the collection that is used for scientific research, as well as education.
So, today, I'm going to show you some really cool skeletal features on turtles and snakes.
Let's take a look.
Here, we have a pond slider specimen that actually was found around North Pond, around the Nature Museum.
So a turtle shell is actually comprised of the carapace, which is the top part,
and the plastron, which is under its tummy.
So I wanted to share with you kind of this big idea
that a lot of people don't realize about turtles,
but their shell is actually part of their skeleton.
The top part of the shell, the carapace,
these are actually comprised of modified rib bones.
The underside is called the plastron and that protects its underbelly.
You can see some different kinds of coloration.
Now, here we have the bony part.
The bony part of the shell is actually protected by what are called scutes.
Now this is a layer of keratin that protects the turtle's shell.
Land turtles, like the pond slider, all have these protective scutes covering the carapace.
And this one you can see is missing several across the top of its carapace.
Let's take a look at another specimen, so we can see what the inside of the shell looks like
So now we're looking at a second pond slider.
Now this one was also collected around North Pond at the Nature Museum,
but this one does not have the plastron, so you can see on the inside.
This is its spinal column, and if you think about how your skeletal structure is actually set up
your spinal column runs all the way down your back and that gives your body its framework.
It's kind of like the architectural skeleton of your body.
Now, a turtle is actually fused to its shell,
because the turtle shell is actually part of its skeletal system.
So if you take a close look, you can see these little suture points where bone comes together.
A suture point is these little tiny divots that are actually where one bone gets fused into another one.
We have them on our skulls, for instance.
Children, babies are born with their skull plates kind of malleable
and then as they grow, they fuse together and they form sutures on our skulls.
So that's exactly the kind of thing that you're looking at here on a turtle's carapace.
So one of the really fun children's stories out there,
like where turtle can leave its shell,
that's not true at all.
Turtles are physically attached to their shell.
So now we're going to take a look at a couple different snake skeletons.
First, let's take a look at this little tiny great plains rat snake.
Now, snakes all have the same kind of body shape,
but what is the big thing you notice about a snake's body?
Well it's missing arms and legs, right?
And that's reflected in its skeletal system.
So, now, we have a skeletal specimen of a bull snake.
Now this one is in pieces.
You can see it's quite a bit larger than our rat snake that we had,
but take a look at that body.
It is composed entirely of spinal vertebrae and ribs.
Here is a closer look at a segment of that.
So just like on our bodies our spinal column goes down our backs.
theirs goes down almost the full length of their body,
and this allows the snake to do that
beautiful undulating movement.
And then the ribs protect all the organs on the inside, just like ours do.
Now let's take a look at another skeletal specimen.
This is a smooth greensnake.
This is a species found in Illinois,
and this specimen was actually collected in the 1940s around the Chicago area.
You can see, here's his little head, his skull,
and then follow along the curvature.
The whole rest of his body is comprised of vertebra and rib bones.
So we looked at both turtle and snake skeletons,
just for some better understanding of their physiology
and what makes their skeletal systems really unique.
Scientific collections, like the one held by the Chicago Academy of Sciences and its Nature Museum,
inform biodiversity studies of all kinds.
They help us learn about the ecosystems that are right outside our back door, so to speak,
and help us gain a better understanding of the plants and animals
that are within nature all around us.
Thank you so much for joining us out at the Collections Facility.
We hope to see you again.