Revolving egg

[TJ]

I received a Hynobius nebulosus CB egg sac today and left it on the table in front of me at work. The eggs are in an early stage of development and the embryos are still round except for one has become shaped like a triangle. It struck me that this particular one was revolving around and around -- in place. At first I thought it must be the result of a breeze or some sort of vibration, but no, it's moving on its own, even when sheltered. And it revolving within the egg sac to boot. Each 360-degree revolution takes approximately 45 seconds. I'll put up some pics later to illustrate this phenomenom.

This may be common knowledge to some people but I find this pretty incredible myself

I mean like, how does it move constantly round and round? And why?

 

[TJ]

In case anybody thinks I'm losing my mind or doped up on TTX, here are some pictures I took while at the office to show what I mean:

The embryo in question is the triangular one at the top.

There were taken at roughly 10-second intervals:

I'm left to wonder what's the method of and explanation for locomotion...

 

[tara]

This happens in sea urchin embryos, but usually only during the late blastula stage. There are tiny cilia on the cells that move, causing the blastula to rotate in the jelly coat. The purpose of this is to keep the egg from sticking to the jelly coat and it also helps them to break free from the jelly coat when it is time to hatch. Also in Chickens there are fine cilia (i can't remember if they are on the chicken or lining the amniotic sac) which keep amniotic fluid flowing over the body of the embryo and help to keep the developing limbs from sticking to each other. I don't know of any examples in amphibian eggs of such cilia, but i suspect if they do exist it would likely be for the same purposes.
tara

(Message edited by edwardst on March 17, 2004)

 

[TJ]

Very interesting information Tara, thanks for that. This revolving went on for several hours and probably would have continued if I hadn't had to leave the office with the sac. Wish I could go back in time and become a biology major. I seem to have missed my calling

(Message edited by TJ on March 17, 2004)

 

[kaysie]

No time like the present, Tim!

 

[angelina]

I recently had a P. waltl egg do the same thing. It rotated for a couple of days and then went opaque. Unfortunately I had to remove it. I'm glad someone else has noticed this besides me! I thought maybe I'd gone nuts!