[18] The slime mould Physarum polycephalum is able to solve the Traveling Salesman Problem, a combinatorial test with exponentially increasing complexity, in linear time.
Bioaugmentation has been suggested as a method to increase the 'intelligence' of microbial communities, that is, adding the genomes of autotrophic, carbon-fixing or nitrogen-fixing bacteria to their metagenome.
[23] V. cholerae has the ability to communicate strongly at the cellular level for the purpose of bacterial transformation, and this form of microbial intelligence involves cooperative quorum-sensing.
[24][25] Two different stimuli that are encountered in the small intestine, the absence of oxygen and the presence of host-produced bile salts, stimulate V. cholerae quorum sensing and thus its pathogenicity.
[26] Cooperative quorum sensing, involving microbial intelligence, facilitates natural genetic transformation, a process in which extracellular DNA is taken up by (competent) V. cholerae cells.
S. pneumoniae uses a cooperative complex quorum sensing system, a form of microbial intelligence, for regulating the release of bacteriocins as well as for differentiating into the competent state necessary for natural genetic transformation.
[29] Natural transformation in S. pneumoniae is an adaptive form of microbial intelligence for promoting genetic recombination that appears to be similar to sex in higher organisms.