Filamentous Bacteria

Original ideas that categorized filamentous bacteria as the stressed and dying members of a population are apparently wrong. This is not a terribly unusual finding since scientists are always correcting ideas; assigning roles to presumably defunct systems and finding mechanisms for what were thought to be random processes.

Filamentation in bacteria occur when the cell continues to grow after its chromosomes have been copied, but the cell doesn’t divide. Filamentous cells are characterized by their elongated shape, which can be 10-50 times longer than normal. Certain bacteria have genes that encode proteins which can make alterations to cell length for the purpose of becoming filamentous, but random mutations can cause deletions in components controlling cell division with a similar affect.

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Human Evolution & History: A Complete Theory [?]

My last few entries have relied on a specific idea that, given a group of non-kin cooperating individuals, the ability to cheaply coerce cheaters is unique to humans. This idea may be the strongest evidence we have for the evolution of human social and sexual behavior., according to this paper, by Dr. Paul M. Bingham.

When multiple remote killing animals kill or threaten simultaneously, they achieve an unexpectedly large decrease in the cost or risk of enforcing individual self-interest. This requirement for simultaneity means that this strategy is viable only when the common, congruent, and thus, cooperative self interests of large numbers of individuals are engaged.

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