Flight imposes strict weight limits, so birds pack enormous numbers of very small neurons into very small brains. Their axons, the long cable-like fibers that transmit electrical and chemical signals between cells, are shorter.

“Long lines take time. Short lines speed everything up,” Nieder said.

I’ve read about this elsewhere, too. It’s really fascinating how corvid brains are packed and constructed, part of why they outperform the usual heuristic of brain mass to bodyweight ratio for estimating intelligence.