mammalian pyramidal cell axon 0.15: squid axon 0.3 μm
||Faisal AA, White JA, Laughlin SB. Ion-channel noise places limits on the miniaturization of the brain's wiring. Curr Biol. 2005 Jun 21 15(12):1143-9. p.1146 left column 4th paragraphPubMed ID15964281
||"[Researchers'] stochastic stimulations establish that the mammalian pyramidal cell axon and the
squid axon have critical diameters of 0.15µm and 0.2µm (Figure 1A, vertical gray lines), and this similarity suggests that an axon’s critical diameter is relatively insensitive to changes in its biophysical parameters."