Is it the "against the stream-cell" that is moving, or the other ones?

fusilli bacteria?

Please don't throw more garbage into the ocean!

The tip of the cantilever consists of a fluorescent bead that contacts the epiblast. Because we know the force necessary to bend the cantilever, we can perform mechanical assays by driving the bead across the embryo and measure in real time the force applied to the tissue.

"Exactly! Epithelia aren't just one thing. They can behave as fluids or solids and exhibit either nematic or polar order. Thank you @epimechfc.bsky.social for highlighting this!"

This paper was inspired by Amélie Chardac's studies on flocking colloidal particles:
journals.aps.org/prx/abstract...
It's pure Physics!