High octane

Pharyngula, a fount of delight and instruction on the brains of octopuses and much else, has long featured a Friday cephalpod (like this).

Once you start to pay attention there is no end to wonders. Here are some more September cephs, gratuitous pictures of Ocythoe tuberculata also known as the football octopus (above and below this text)...


...and Argonauta argo, or paper nautilus

Octopuses have three hearts and copper instead of iron to carry oxygen in their blood.