English: Illustration of bacterial condensation and range expansion. Top: When cells are inoculated within a nutrient-rich environment they consume nutrients and multiply, leading to outward-pointing gradients. By following these self-generated gradients, cells rapidly expand into fresh territories. Bottom: Bacteria may also change the chemical environment around them in a way that attracts others by either secreting attractant (positive) molecules or removing repellent (negative) molecules. Combined with their ability to follow these self-generated gradients, positive feedback forms, leading to the formation of macroscopic condensates.