Sheep flow like liquid blobs as they are herded by shepherd dogs. So much like a liquid, in fact, that a group of physicists modeled them using the principles of fluid dynamics! arxiv.org/abs/2002.09467
Step by step, two researchers transform flocks of sheep into abstract fluid flows. arxiv.org/abs/2002.09467 
* Correction: The researchers are an animal biologist & a biophysicist.
