I thought it might be time to have a look at a few of the varieties of squid, since there’s a lot of them that we don’t get to see much.
For starters, there’s the vampire squid: it’s covered in light-producing organs called photophores, which can produce disorienting flashes of light to confuse predators. It also has the ability, when threatened, to invert its arms and cape back over its body, producing what looks like a much larger creature covered in apparently dangerous (although actually harmless) spiky protrusions – here‘s a video of it turning itself inside out.
Then there’s the tiny bobtail squid, shown above. This little cutie (with a mantle between only 1 and 8 cm) has a symbiotic relationship with bio-luminescent bacteria that inhabit a special organ in the squid’s mantle: the squid provides food for the bacteria, which then hide the squid’s silhouette from below by matching the amount of light hitting the mantle. There’s more detail about how this happens in the Wikipedia article here: I do suggest you have a quick read, because it’s quite fascinating.
For an extra bit of squiddly cuteness, have a look at the banded piglet squid. Another tiny creature, although slightly larger (up to 10 cm as an adult), the paralarvae (young) of this one appears to have a little smiley face. What more could you ask from a sea creature?
And we can’t forget the famous giant squid (video here). Although we don’t know much about them, we know that there’s very low diversity in their population, and that a decrease in squid numbers is causing stomach ulcers in toothed whales that feed on them. If you’re interested in seeing just how big they are, the South Australian Museum in Adelaide has a model of the largest squid recorded to date, which was found in New Zealand waters. It’s 11 metres long, is housed in an old lift shaft which descends over 4 floors, and is very impressive. They’ve also got a specimen preserved in alcohol in the Science Centre of the Museum – while I’ve not seen this one, I’m prepared to take it on trust.
There are plenty of other squid species, for those who are interested in such things – this is just a sample, from the largest to the smallest, from those that inhabit the deeps to those inhabiting the shallows. Let the (squid) games begin!