Yesterday, I showed off a few embryos I’d collected from my fish tanks that morning — they were at roughly the 16 cell stage. Then today, I put up a video of the same beast at 24 hours old. It was a bit busy, because this is the age when they are going through all kinds of spontaneous muscle contractions, so I also anesthetized one of its siblings and tossed that on the scope. Stoned fish are so much more cooperative.