so I found tHIS SPECIAL GIRL ON THE INTERNET and had a squeal

what originally was a question about 'hey what are those orb things on its arms' turned into a deep dive on marine biology

so, hey, Let's Learn About The Blanket Octopus!

(img source: https://twitter.com/echinoblog/status/951505827751280640 ) https://awoo.space/media/wARGgKAybScwXwCbK3o

This special special girl seen above is a blanket octopus, Tremoctopus sp.

They're typically found in tropical oceans, not too far from the surface. Gulf of mexico, Great Barrier Reef, so on.

The thing that sticks out the most is- well, that blanket! That giant web-frill it has is actually a defensive mechanism. The unfurled blanket makes them look *much* larger, and can detach from its body and swim away if a predator bites into it.

(i mean, yeah, if i was an octopus-eater and i saw this swimming by, i'd probably try to grab it by that blanket too. oops! It comes off, and the octopus swims away.)

But that's not the only interesting bit of intel about this species! They actually have a bunch of fucky shit goin' on with 'em.

https://awoo.space/media/5nsSpgXGqDuSwqp0IPg

[img source: http://tolweb.org/Tremoctopus ]

One:

That bit where I said /females/ were about ~2m long? Males are...~2cm.

Centimeters.

This species has one of the most extreme sexual dimorphisms known, by a weight diff of somewhere between 10-40,000 to 1.

That's like a human female being normal-sized
and a male being a walnut.

Relatedly, that's why it took until 2002 to actually spot a live specimen in the wild. by chance. on a night dive.
(this is a tiny, tiny boy)

Two:

the male kinda is just there to reproduce! when it gets to be time, they take their hectocotylus (one of their arms that basically just evolved to be the Horny Arm, its full of sperm)

and detaches it
and just sticks it to the side of the female's head for her to use later

Octopus reproduction, while beautiful, is kind of a one-time deal for both. The male dies shortly after the act, and the female lives long enough to have eggs hatch.

Three:

The species are typically *completely immune* to the sting of the Portugese man o' war- these things. They look like jellyfish but they're a colony of siphonophores, they're floating rafts of pain, in some rare cases lethal to humans.

Three-point-a:

When blanket octopi are small (read: male-sized), they *rip the tentacles off of these and USE THEM AS WEAPONS.*

like a whip
made of poison.

[img source: https://www.nationalgeographic.com/animals/invertebrates/p/portuguese-man-of-war/ ]