200 to 1 in mouse: 3,000 to 1 in human Unitless
||Williams RW, Herrup K. The control of neuron number. Annu Rev Neurosci. 1988 11: 423-53. p.429 2nd paragraphPubMed ID3284447
||Wetts R, Herrup K. Direct correlation between Purkinje and granule cell number in the cerebella of lurcher chimeras and wild-type mice. Brain Res. 1983 Oct312(1):41-7. AND Lange W. Cell number and cell density in the cerebellar cortex of man and some other mammals. Cell Tissue Res. 1975 157(1):115-24.PubMed ID6652508, 804353
||Abstract of 1st primary source gives ratio of 175 to 1 in mice.