Sweetest Eel Eats Yumyums
This post is gonna be quick. Apologies. Must get to sleep. Tsetse, tsetse.
It’s not nice, really, to keep calling my fatigue tsetse. Tsetse fly transmitted sleeping sickness is a pretty horrible deal, and involves much more than fatigue.
Still, it’s sorta catchy. I enjoy the repitition. Tsetse. Yumyums. Jawjaw.
Jawjaw? That’s what I’m gonna quickly tell you about or, more specifically, direct you to.
New discovery - moray eels have a second, secret ’till now set of jaws that extends forward when they open their mouth wide. These secret jaws grab into and onto the food, and pull it back into their gullets. Mmm.
Our jaws come from a series of pharyngeal slits that all vertebrates have. Ours - those are the “gill slits” that we’ve got when we’re embryos. One set of ours turn into jaws. Then, the rest turn into things like ears and…inner head parts.
In other vertebrates, like fish, the pharyngeal thingies turn into jaws and gills.
I’m sure it’s much more complex than my explanation here. And o how I would love to tell you about the characteristics that all vertebrates have in common. I’ll tell you this now - one of the characteristics or features that ALL vertebrates have is this: they all have pharyngeal slits.
How does this have to do with tsetse and yumyum and eels? Eels use one pair o’ slits for jaws, and then they use yet another set of pharyngeal slits to make that second, inner, secret set of jaws, the jaws that come forward to clamp down on their prey. Jawjaws snatch yumyums. Hooray for moray!
PZ Myers has an excellent description of the process on his blog, Pharyngula. Here’s the link. He’s also got pictures and video, showing that second jaw coming forward.
Now, here’s some illustrations of a human embryo, showing the pharyngeal structures and what they are busy doing. Arch=slit=pharyngeal structure that we’ve been talking about. Mandible and maxilla = bottom and top jaws.
18-21 days old
27-30 days old
Wilhelm His (1831-1904)
1888 - Anatomie menschlicher Embryonen
moray eel, eel, jaws, Pharyngula, development, embryo, fetus, pharyngeal slits, gill slits, vertebrate, gills, yumyum, tsetse, PZ Myers
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