Little Tom Thumb among cells : seeking the cues of life

For a living being or a cell in a developing body, recognizing its peers and locating food sources or other targets and moving towards them is of paramount importance. In most cases this is achieved by detecting the presence of chemical substances in the environment and moving towards the areas of their higher concentration, a process known as chemotaxis. Despite its fundamental role for life, this phenomenon is not yet fully understood in all its details and mathematical models are proving very useful in guiding biological research. We address here two examples of chemotaxis occurring in the developing embryo: early formation of the vascular plexus and axon navigation in the wiring of the nervous system.