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Hello from the Gulf Coast


Larval Mass
Feb 1, 2012
Hi all.

As a sport diver for over 30 years I've always been fascinated by cephalopods and their many adaptations & intelligence.

I'm currently working as an informal marine educator, and one of my tasks is to develop brochures on cephalopods for a general audience. Have most of the basic info needed, but if anyone has any obscure/fun facts about these interesting creatures that could be included I'd love to hear them.

Mike :snorkel:


Oct 15, 2011
3/5 of an Octopus brain is located in it's ARMS (not tentacles sorry)

Lens of an octopus is rectangular

I'm just making suggestions :smile:


Staff member
Sep 4, 2006
Gainesville, GA
I would like to see you qualify statement with most or many and not all and dispell some of the misinformation often copied from one piece of literature to another. We continuously see things like all octopuses are nocturnal (many are either diurnal or crepuscular one, O. cyanea, is commonly named the Day octopus), all cephalopods are Semelparous (but we now know of at least one octopus (O.chierchiae) and two cuttlefish (s. bendensis and Metasepia pfefferi) that produce multiple egg clutches, squid don't brood eggs (but there is a deep water species that does), mating causes death (matuation causes death - attributed to the optic gland - not the act of mating and a female octopus will lay infertile eggs at the end of her life if she has not mated). Also little annoyances like there is a difference between arms and tenacles when talking about cephalopods (legs are kind of up for grabs with recent observations but not commonly accepted at all). Octopuses have 8 arms, squid have 8 arms and two tentacles and the functions and appearances are different.

Tidbits off the top of my head:
-Some cephalopods carry their eggs where other attach them to the substrate.
-The paper nautilus is an octopus and the "shell" is an egg casing.
-Like seahorses, there are two kinds of octopus hatchlings. Some species produce small eggs that hatch as pelagic paralarvae where other species produce larger eggs (and larger hatchlings) the look like the parent and are benthic soon after birth.
-Octopuses have a toxin to neutralize their prey but only two types can kill humans with their toxin(a couple of blue ring species and O. mototi)
-Octopuses have been found in quantity at the sites of the thermal vents, in antartica, the artic as well as near the equator
- Recently discovered fossils show octopuses existed long before we thought and have not changed much in 95 million years

I am sure I have forgotten other obvious oddities but hopefully, I have added a couple to your list.

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