For those of you not constantly thinking about ocean creatures, it may have escaped your notice that it’s Cephalopod Week. But that’s okay – we’re here to remedy that unfortunate situation.
What is a cephalopod?
Cephalopods are a class of mollusk, the diverse group of animals that lack a spine including clams, snails, and octopi. Specifically, the term cephalopod refers a wide variety of squid, octopi, cuttlefish, and nautilus. In total, there are over 800 species of cephalopods, and this number is growing. Recently, social media exploded with the discovery of what is believed to be a new octopus species that is so cute, it could be named adorabilis.
Why do we call them cephalopods?
The term cephalopod is Greek for “head-feet”, referring to the appearance of having feet (or tentacles) attached directly to the animal’s head.
What makes a cephalopod so cool?
There are a whole lot of reasons why cephalopods are so cool. But in honor of Cephalopod Week, we’ve picked a few of our favorite cephalopod facts to share:
- They’re super smart. In fact, cephalopods are believed to have one of the most advanced nervous systems of all the invertebrates! And with a centralized brain, they’re able to learn and remember.
- They’re really good at camouflage. Check out this mimic octopus
…and this cuttlefish
Many cephalopods have special organs in their skin called chromatophores. These organs contain sacs of pigment that are manipulated through muscle contraction to change the color of the animal.
- Some are considered “living fossils”. The nautilus is the last living species of its type. And it’s thought that it hasn’t evolved much in the last 500 million years.
- Cephalopods can range in size from 5 mm to over 15 m in length! The giant squid, Architeuthis, which lives in the North Atlantic, is the largest invertebrate on earth. And get this, its eye may be 30 cm wide…that’s the size of a car’s hubcap!
- Cephalopods usually have three hearts. Two of these hearts pump blood to the gills and one central heart pumps oxygenated blood to the rest of the body. And, they have blue blood! Instead of binding oxygen using iron like humans do (this makes our blood red), cephalopods bind oxygen using copper, which makes their blood appear blue.
Here at Kraken & Friends, we’re particularly fond of cephalopods, in fact, we got our name, the mighty kraken, from a cephalopod. The kraken is a legendary sea monster, believed to originate from sightings of giant squid or octopi. And because of that, we hold a special place in our hearts for the mighty cephalopod.