Interesting facts about Octopus Biology
& tips on octopus friendly choices you can make
This 8 armed, beak wielding, marine invertebrate belongs to a family (Cephalopods) of approximately 300 species worldwide. They're known for their camouflage abilities, intelligence, and generally for being weird yet wonderful creatures of the blue. So why are they cool? Aside from how they look like aliens, or how they can squeeze into tiny places, they've got a few things about their biology that makes them cool.
1) Three hearts
All vertebrates have 1 heart, yet the octopus has 3. One pumps blood to the body, and two pump blood to the gills. An octopuses gills work by the octopus bringing in water via the mouth, to which it's then passed through the gills and then out again. As the water is pushed through the gills, its the blood in the capillaries of the gills that pick up the oxygen from the water. Which is then diffused and makes its way into the bloodstream to be circulated around the body. Another thing worth mentioning is octopuses blood, which is blue. The blue is caused by hemocyanin, the copper-containing protein that binds oxygen in the octopus. Human blood is red because of haemoglobin, which contains iron.
2) Three means of transport
Picture an octopus as a car, but with three gears. In times where there is no particular hurry to get anywhere, or in times of laziness, the octopus will walk along the ocean floor with its arms. If It's not walking, it's usually swimming by flexing its arms and body. Or, if the situation requires it, the octopus can expel a jet of water from its body cavity causing it to propel away with great speed, this means is usually coupled with the releasing of a blob of ink, which confuses predators, and allows the octopus to jet away to safety without being followed.
3) Three types of specialised skin cells
The octopus can change the colour, texture, reflectiveness and opacity of its skin with a moments notice. These abilities allow this blobby invertebrate the ability to easily blend in with its surroundings. As for those Three skin cells. Chromatophores, which are responsible for the production of red, orange, yellow, brown and black colour pigments in the skin. Leucophores cells which mimic white, and Iridophores which are reflective and are ideally suited to camouflage. More on this in the video below.
4) All species of octopus are venomous
That's right! All but one aren't harmful to us, and the majority use their venom for hunting, such as paralysing a clam into opening its shell. There's plenty of evidence in the scientific literature suggesting that the actual octopus doesn't make the venom itself, but instead its produced by symbiotic bacteria present within skin cells. Not all octopuses are fatal to humans, but the most deadly to us is the blue-ringed octopus which funnily enough is about the size of a golf ball! Their venom is highly toxic, and there is no known antivenin to it!
So by now, we all know that octopuses are cool. Yet I bet you didn't know humans are the octopuses biggest threat. We're destroying their habitats and hunting grounds, we're out-competing them for their main food sources and we're causing damage to their numbers by pollution and climate change. Plus, on top of everything else we're doing to them, we're also hunting them for food, as well as bait to catch other marine going organisms. So that's obviously not great. Yet there are some small things that you can do to help keep octopus numbers stable.
What you can do to help:
1) Don't eat octopus (Don't contribute to the demand to kill) they're friends, not food...
2) Don't keep octopuses as pets
3) Don't buy gifts containing octopus beaks.
4) Cut down/stop your consumption of molluscs, crayfish, and crabs. Just consider that your main diet doesn't depend on those food sources, but an octopus's does. You can easily pick something else off the shelf in the shop, but an octopus has to find, hunt, and catch its meals.