Figure 3.

Illustration of the tendency of phages to display biases towards acquisition of locally available bacteria. Here shown to the right is phage acquisition of a bacterium (blue) that is found as part of the same arrangement as a lysing bacterium (red with dashed border). The green arrows represent outwardly diffusing phage progeny released upon bacterial lysis while the shorter, gray arrows illustrate the tendency of those phages that are released immediately adjacent to an uninfected bacterium to encounter that bacterium. Contrasting this second bacterium looming large in the vicinity of an adjacent phage burst, even at a high plankton bacterial density of 10⁸ per mL, each free bacterium (left) occupies a total environmental volume of 10⁴ µm³ (1 cm = 10⁴ µm, meaning that 1 mL = 1 cm³ = 10¹² µm³, where 10¹² µm³/10⁸ bacteria = 10⁴ µm³/bacterium). This density in turn implies an average distance between bacteria of about 10^4/3 (i.e., the cube root of 10⁴ µm³), or more than 10 µm, which one may compare with a typical bacterium diameter of about 1 µm. Thus, bacteria in arrangements can be not-unreasonably described as having local densities that should encourage phage adsorption with higher likelihood than that seen among planktonic, individual bacteria.