Squid Eye Bioluminescence

[GPO87]

I found this photo on google:


Firstly, it reminded me of some sci-fi movie, where the aliens eyes are glowing... but after I switched from geek mode to scientist mode (I know, there really isn't a HUGE difference with me), I realized that this wasn't completely reflection from the flash, the light produced was partially from photophores.

How cool is that!?! (The answer, is "pretty cool").

To add to the coolness, check out the coloration variations between the squid in this picture!
I know what your thinking now... and yes, it is pretty cool!

 

[Tentacle Toast]

...that...is ...pretty...cool...! Did you catch where/when the photo was taken? Can you identify any of them? There looks to be a couple different body types, but might just be their angles.

 

[robyn]

Hm, I don't think it's bioluminescence for a couple of reasons - if you looks closely at the photo, the bright patches around the eyes are angle-dependent. The uppermost squid on the right is almost facing the camera - note that unlike the three in profile, the ventral half of his eye is not bright. Also the reflectance from the two facing the camera that shines through the front of the faces is spatially greater than what is being reflected through the face of the front one. The guy at the bottom, looking up, has a bright patch dorsal by the eye, compared with more medial, tending ventral of the two looking straight at the camera.

This is all quite characteristic of structural coloration, iridescence.

Squid eyes are extremely reflective, a very bright silver covers the whole eye cup under the skin, even on the back side facing the brain. I've seen similar effects of bright eye reflectance in photos I've taken of Loligo. They are also covered in iridocytes - cells that are packed with highly reflective proteins that reflect light at different wavelengths. I think that's the effect here, not bioluminescence.

Do you know what species they are? The look like L opalescens or Sepioteuthis to me, which are both beautifully iridescent.

 

[GPO87]

Robyn:
Upon getting up this morning (after having some sleep), and reading your comment, I see that you are right. (Just goes to show I shouldn't post in the wee hours of the morning! haha). But still the irridescence causes a beautiful effect.

I'm pretty sure I read on the website that these were taken around Hawaii... I could be wrong though.