Experiments carried out with motile bacteria in liquid culture show that bacteria interact through the growth medium by increasing the mean distance between two neighbouring bacteria. This interaction which has the same macroscopic effect as a repulsive force is a consequence of bacterial chemotaxis. Perhaps, it can explain the reason why prokaryotic cells have never engendered multicellular organisms, which, on the other hand, appeared on the Earth immediately after the eukaryotic cell.
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Con il contributo del Ministero per i Beni e le Attività Culturali