Collection of interesting natural things

I took the picture above to see if I could get a good shot of the ocelli - three secondary eyes between the big ones. They are just about visible. Why spanning tree? It's a routing term, from each user's perspective the network looks like a spanning tree - with no loops and only one route to any place. Every user's spanning tree is unique.

Pineal in tuna

SciencePosted by Jay Thu, March 22, 2012 13:59:30
I have been meaning to consider the pineal apparatus in tuna in more detail. In tuna the structures around this instrument are well developed.

Here is an MRI scan that the people at Hobart Hospital were kind enough to do for me. I'll just post these here for interest while I go off and do something else. The pineal window is the oval white structure in the middle - just in front of the brain. A picture from the side may be better to see the detail. The side picture shows much more interesting stuff...

You can see the heart in the 'throat' and the oil filled holes along the backbone - these should be familiar from cans of salmon - where they are often preserved as little round disks. Anyhow, the brain and the pineal window are all quite clear from this picture an it can be seen that light from above can illuminate the semi-spherical nodule at the front of the brain. I suspect this is related to navigation. We wrote a paper about it...