Here's an except I just found on some hair research:

The researchers analyzed over many months the changes in the hair growth patterns on shaved mice and rabbits, which indicate cyclic progression between active and quiescent states by stem cells in hair follicles.

"The results are totally surprising. There is complex coordination not apparent to the naked eye," said Cheng-Ming Chuong, professor of pathology at the Keck School and the principal investigator of the study funded by the National Institutes of Health.

The "complex coordination" Chuong refers to is the ability of the large hair stem cell population to communicate with each other to reach robust hair growth, manifesting in a constantly shifting hair wave pattern that often looked like a piece of abstract artwork "painted" on the rabbit's skin.

The scientists found that hair stem cells coordinate their regeneration with each other with the aid of a pair of molecular activator WNT and inhibitor BMP. When WNT and BMP signals are used repetitively among a population of thousands of hair follicles across the entire skin surface, complex regenerative hair growth behavior emerges via the process of self-organization.

The research holds potential for finding a cure for alopecia, or hair loss, by improving the environment for communication. Alopecia occurs in humans partially because stem cells in human hair follicles, unlike those in mice and rabbits, have lost the ability to communicate with each other.

"When each human hair follicle wants to regenerate, it can only count on itself; it's not getting help from other follicles," Chuong said. "But when a rabbit hair follicle regenerates, it can count on two inputs: its own activation, and the activation signal from its neighbors. Rabbits have a very active hair growth, and that is essential for their survival in the wild."