And it turns out the answer to that is because their brains are packaged inside their skulls in a way different from the way our brains, we being human beings, true, have our brains packaged.
この答えは― キツツキの脳は 頭蓋骨の中に入っているわけですが そのおさまり方が 私たちの脳―人間の脳とは 違うというのです