Chemical Signaling as a Proxy for Population Density

How a small molecule continuously released by every cell in a population lets each individual cell gauge, purely from local concentration, roughly how many neighbors surround it.

References

• Williams, P., Winzer, K., Chan, W.C., Camara, M. "Look Who's Talking." Philosophical Transactions of the Royal Society B 362, no. 1483 (2007): 1135–1145.