- **Sparse inter-regional connectivity debate**: Participants questioned how only a few thousand long-range axons can carry enough information between cortical areas; muurkha estimated 3–7 bits per spike if spike timing relative to a “clock” is used, and noted that human sound localization already exploits sub-millisecond phase differences.

- **Cortical firing-rate estimate**: lsneff cited AI Impacts data that the entire human cortex fires ≈ 2.7 × 10⁹ spikes s⁻¹, reinforcing the view that biological computation is far more “compute-sparse” than today’s ANNs.

- **Absolute neuron count as the key cognitive variable**: kanzure linked multiple papers (Herculano-Houzel et al.) showing that human cognitive advantages correlate with the absolute number of cortical neurons (≈ 16 billion) rather than relative brain size or encephalization, and that the prefrontal cortex holds only ~8 % of cortical neurons in all primates.

- **Neuron-counting methodology**: discussion highlighted the “isotropic fractionator” (turning brains into soup to count nuclei) and its use in elephant, primate, and dinosaur brains; kanzure wondered whether any protocol preserves dendritic trees for connectomic analysis.

- **Wetware & hybrid bio-digital systems**: links to Cortical Labs’ “DishBrain” (in-vitro human neurons learning to play Pong, Neuron 2022) and Koniku’s pivot to odor-sensing biological chips were shared as examples of engineered neuronal systems.

- **Holographic brain theories**: nsh argued that David Bohm and Karl Pribram’s holographic models (lower-dimensional encodings that reconstruct higher-dimensional information) are essential for understanding how space, time, and information interact in cognition.

- **Open-source cryptographic hardware**: kanzure announced the “Silicon Salon 3” workshop with bunnie Huang and offered tickets for those interested in open silicon.

- **Transgenic ants achieved**: first transgenic ants expressing GCaMP in the antennae were reported (bioRxiv 2022.12.04.518909), enabling optical imaging of alarm-pheromone responses in ant glomeruli.

- **Embryology & chimerism**: kanzure sought a modern review of homeobox/hox genes in embryology and shared a paper on “multi-scale chimerism” (DNA transfer, grafting, parabiosis) as a window into anatomical control algorithms.

- **Stellar biology tangent**: superkuh and kanzure discussed Robert Forward’s *Dragon’s Egg* and other science-fiction treatments of plasma-based life inside stars, prompted by a Hacker News thread on self-replicating organisms in stellar interiors.