Two adult worm maps showed no clear gain in fixed-sample input-source diversity for 37 selected brain cells

We tested whether input contact growth spreads input across more source neurons after sample size is fixed. We used eight public C. elegans developmental brain maps and a published 162-cell panel. Thirty-seven targets had at least ten contacts in every map. Mean contact count rose from 21.05 at birth to 100.30 and 108.78 in two adults. The expected source count in ten sampled contacts changed from 7.079 to 6.999 and 6.919. Paired changes had cell-class bootstrap ranges of -0.433 to 0.221 and -0.500 to 0.144. Five-contact and source-class sensitivity tests also left adult changes uncertain. This does not prove constant diversity. In an equal-gain model with independent source fluctuations shared across contacts, mean input variance fell by 22 to 23 percent; an independent-contact reference gave 77 to 78 percent. These are model results, not measured neural noise. Separate animals at each age, panel selection, missing external inputs and unmeasured contact gains limit the result. Code, edge counts, source hashes, checks and a figure support reproduction.

C. elegans · development · input diversity · rarefaction · connectomics · shared source activity