By Tursiops_truncatus_brain_size.JPG: Boksiderivative work: Looie496 (Tursiops_truncatus_brain_size.JPG) [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons
Tursiops truncatus (bottlenose dolphin) brain compared with brains of wild pig (Sus scrofa) and a plastic model of a human brain (Homo sapiens).