Squid vs Octopus – Difference and Comparison
The anatomy is different:
Squid: How Squid Work
Octopus: How Octopuses Work
These are both amazing alien like animals that are iridescent and awesome to observe in their environment. They are the SPIDERS FROM MARS!
My personal difference is that I’ve been bitten by octopus (my fault, not the animals-Don’t handle wild animals!), but never a squid.
I was very young in San Felipe Mexico, handling the octopus and its tentacles attached to my arm. I thought I was cool and it was cute until the beak broke my skin. I released the animal unharmed. The bite also gave me an overall sick reaction for about 24 hours after.
Both have beaks. They are phylum Molluska, and while they don’t have shells, they do have a shell-like beak, almost like a parrot.
Octopus inject venom after the bite.
From a diving perspective, both are more active at night.
Though I have seen a zillion squid beaching themselves in the Sea of Cortez and the hour of day didn’t seem to matter.
I’ve never observed a squid with personality. I have observed octopus with personality, like they are squid’s nerdy honor roll cousins. 🙂
Squids just swim, and swim and swim.
Squid swim in the open water and can school. I wish I could tell you I’ve dove with schooling giant squid but I have not. I have avoided that thrill on purpose, for personal safety.
Octopus live in rocks, crevices and caves. They are very witty. I’ve never observed this muppet like intelligence from a squid. This is rare footage. Usually in the day they are deep inside the rocks. We might see a part of them, but generally when we approach they disappear. Sometimes we can see the eyes looking out from behind a rock, but then if they are approached they dart back into their crevice.
https://www.youtube.com/watch?v=x5izINmi5Fg
The sickening thing is that in order to supply aquariums, sushi and other restaurants, bleach is often injected into the rocks or reef to get the octopus to come out. It’s not a myth- it’s very obvious. When I’m diving I can sometimes find the empty plastic bleach containers. It kills the rocks and reef, bleach is poured into the environment and yes I’ll bet that people who eat these animals are eating the bleach (or whatever other chemicals used) too. We are killing off our octopus, reefs and oceans in this way.
Squid, because they are in the open water, are netted which makes them both more elusive and easier to catch, though the nets are tragically dangerous and destructive to the ocean and everyone who lives in it or enjoys it.
Another difference is that I’ve seen footage of an octopus eating a shark. I’m not sure a squid can handle that.
Night dives offer the opportunity to see both animals at their peak. Both species might not live in the same ocean area, so don’t expect to see both (but it can happen!)
Both animals boast amazing color and camoflague capability. When an animal dies all the epic coloration fades immediately. Try to see them in their environment when you can see how psychedelic their iridescence is. Squids and Octopus are both gifted with this and both very beautiful in different ways. Squids almost seem to have multicolored psychedelic running lighting.
Camouflage is the gift of all of the cephalopods.
https://www.youtube.com/watch?v=eS-USrwuUfA
How Octopuses and Squids Change Color
The other very cool related animal is the cuttlefish. You can learn more here:
https://www.quora.com/Marine-Biology-Can-a-Cuttlefish-change-its-skin-texture-and-colour-to-mimic-its-surroundings-with-its-eyes-shut-or-covered
This post originally posted on Quora, but was deleted by their moderator due to external links (which I thought were visually necessary) hence here we are ;). Enjoy!