Cuttlefish
Apr. 28th, 2017 11:08 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
pheloniusfriarI get very emotional about cuttlefish.
Cuttlefish, like other cephalopods, have sophisticated eyes. The organogenesis and the final structure of the cephalopod eye fundamentally differ from those of vertebrates such as humans. Superficial similarities between cephalopod and vertebrate eyes are thought to be examples of convergent evolution. The cuttlefish pupil is a smoothly curving W-shape. Although cuttlefish cannot see color, they can perceive the polarization of light, which enhances their perception of contrast. They have two spots of concentrated sensor cells on their retina (known as foveae), one to look more forward, and one to look more backward. The eye changes focus by shifting the position of the entire lens with respect to the retina, instead of reshaping the lens as in mammals. Unlike the vertebrate eye, there is no blind spot, because the optic nerve is positioned behind the retina.
It has been speculated that cuttlefish's eyes are fully developed before birth, and that they start observing their surroundings while still in the egg.
Cephalopods are remarkable for how quickly and diversely they can communicate visually. To produce these signals, cephalopods can vary four types of communication element: chromatic (skin coloration), skin texture (e.g. rough or smooth), posture and locomotion. The common cuttlefish can display 34 chromatic, six textural, eight postural and six locomotor elements, whereas flamboyant cuttlefish use between 42 and 75 chromatic, seven textural, 14 postural, and seven locomotor elements.
While blogging is pretty spiff, and flapping my jaw and flailing my limbs seems to work okay, I am deeply humbled by our cuttlefish friends.
This post was brought to you by the song "Your Attitude Toward Cuttlefish" by the Winnipeg band Paper Moon, off the compilation album "For The Kids Two!" (which I was listening to while trying to learn a 3D solid modelling CAD program so I can do sketches for the projects I'm working on). I really do get emotional listening to that song, and it's one of my favourite pieces of music in the world for some reason (the reason actually eludes me... maybe it's the song... there is a rare innocence about it... maybe it's cuttlefish... if you ever lose me at an aquarium, just find the cuttlefish and I will probably be trying to interact with the denizens in the tank). I can't find a link to the song (Canadian indie music can be hard to find... sigh...), but I think it's on Spotify and other music services, none of which I have.
P.S. Cuttlefish = Aliens = Awesome! Right???
Cuttlefish, like other cephalopods, have sophisticated eyes. The organogenesis and the final structure of the cephalopod eye fundamentally differ from those of vertebrates such as humans. Superficial similarities between cephalopod and vertebrate eyes are thought to be examples of convergent evolution. The cuttlefish pupil is a smoothly curving W-shape. Although cuttlefish cannot see color, they can perceive the polarization of light, which enhances their perception of contrast. They have two spots of concentrated sensor cells on their retina (known as foveae), one to look more forward, and one to look more backward. The eye changes focus by shifting the position of the entire lens with respect to the retina, instead of reshaping the lens as in mammals. Unlike the vertebrate eye, there is no blind spot, because the optic nerve is positioned behind the retina.
It has been speculated that cuttlefish's eyes are fully developed before birth, and that they start observing their surroundings while still in the egg.
Cephalopods are remarkable for how quickly and diversely they can communicate visually. To produce these signals, cephalopods can vary four types of communication element: chromatic (skin coloration), skin texture (e.g. rough or smooth), posture and locomotion. The common cuttlefish can display 34 chromatic, six textural, eight postural and six locomotor elements, whereas flamboyant cuttlefish use between 42 and 75 chromatic, seven textural, 14 postural, and seven locomotor elements.
While blogging is pretty spiff, and flapping my jaw and flailing my limbs seems to work okay, I am deeply humbled by our cuttlefish friends.
This post was brought to you by the song "Your Attitude Toward Cuttlefish" by the Winnipeg band Paper Moon, off the compilation album "For The Kids Two!" (which I was listening to while trying to learn a 3D solid modelling CAD program so I can do sketches for the projects I'm working on). I really do get emotional listening to that song, and it's one of my favourite pieces of music in the world for some reason (the reason actually eludes me... maybe it's the song... there is a rare innocence about it... maybe it's cuttlefish... if you ever lose me at an aquarium, just find the cuttlefish and I will probably be trying to interact with the denizens in the tank). I can't find a link to the song (Canadian indie music can be hard to find... sigh...), but I think it's on Spotify and other music services, none of which I have.
P.S. Cuttlefish = Aliens = Awesome! Right???
