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  • My time has finally come.

  • Today, I get to talk about Cephalopods

  • Hey guys, Julia here for Dnews

  • Octopi and their fellow cephalopods scare the living daylights out of my sister.

  • Something about a traumatic trip on the 20,000 leagues under the Sea Ride….

  • So sister, you should probably turn off this episode, because it turns out, there's a

  • lot to be afraid of.

  • Okay in my opinion there's a lot to love about these molluscs.

  • Like a recent discovery that some species of octopuses can see through their skin.

  • Seriously.

  • Octopuses make a chemical in their eyes called opsins, which react to light, and send a chemical

  • signal to the brain.

  • In two studies published in the journal of Experimental Biology, researchers found that

  • these molecules can also be found in their skin.

  • In octopuses, these molecules are in nerve endings on the cell.

  • These little hair like extensions detected light and send a chemical signal to specialized

  • color changing cells on their skin called chromatophores.

  • In other cephalopods like squid and cuttlefish, opsins are actually found in the chromatophores

  • themselves.

  • Scientists think this might be how cephalopods have such an uncanny ability to blend into

  • their surroundings.

  • Oh yeah these guys are masters of camouflage.

  • I mean, some cephalopods have have up to 96,000 chromatophores per square inch of skin.

  • Each of these chromatophores contain a sac of pigment surrounded by muscle and by stretching

  • or squeezing this sac, they can change the appearance of their colors.

  • Some species of cephalopods have other crazy color cells, like iridophores which make iridescent

  • colors, or leucophores which mirror back the environment.

  • But besides changing colors, some cephalopods can change texture.

  • yeah crazy, In a study published in the Journal of Morphology researchers found that cephalopods

  • have small muscular structures on their skin that either poke up vertically in a spike

  • or bump or spread out nice and smooth.

  • So they can morph into crazy patterns and changing textures in their environment, like

  • mimicking corals, rocks or sand.

  • Or mimicking other sea creatures like T. mimicus, an Indo-Pacific species of octopus.

  • Not only are they great pretenders but they are crazy crazy smart.

  • Like they've been known to pull pranks and play in captivity.

  • According to Canadian biologist Jennifer Mather, they blow water at stuff in their tanks or

  • take apart stuff like robots, just for the fun of it.

  • And play is something thought to only be found in intelligent creatures, like birds and apes.

  • There's so many stories of them sneaking out of their tanks at night and stealing a

  • fish or two from a nearby tank then plopping back in their tank and acting like nothing

  • happened.

  • Mather even noticed that octopuses have personalities, different creatures are more shy or active

  • than others.

  • These come from their big brains, well relatively.

  • They're brains aren't as big as ours per say, but bigger than many other molluscs.

  • Most molluscs havebrainsthat are actually clusters of nerve cells spread throughout

  • the body.

  • But cephalopods have a more centralized group of these ganglia, or nerve cells.

  • This centralizes command in the creature and provides more room for developing things like

  • memory.

  • They also have little mini brains or groups of nerve cells in their arms!

  • I haven't even mentioned that cuttlefish are adorable and cuddlyan octopus has

  • a beak or some species have an arm, called a A hectocotylus, that acts a lot like penis

  • by storing and transferring sperm to the female.

  • Which just gets weird.

  • Speaking of the weird and wonderful, Laci explains all about real life sea monsters

  • in this great video here

My time has finally come.

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How Octopuses See With Their Skin

  • 11 3
    joey joey に公開 2021 年 04 月 18 日
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