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Sort of a request! Someone asked for nautiluses and cephalopods. I've actually done a squid post before, several octopuses have been shown previously, but certainly more won't hurt! Since squid have had a post, this one's just for shelmets nautiluses and octilleries octopuses.
But first, a quick introduction to these interesting animals! Nautiluses have been called living fossils, which is definitely a fitting title for them as they haven't changed in literally millions of years. Even though they might not look much like squid, they share similar heads and tentacles to them- but unlike squid and octopuses, can have dozens and dozens of tentacles poking out at a time. And VERY unlike squids and octopuses, they have shells, which grow up along with them. If you've ever picked one up in real life, you'll notice that the top is usually banded and the bottom is white. There's a reason for this! It's because when the nautilus is upright in the ocean, animals looking at it from above see it as the same shade as the water below, and animals looking at it from below see it as bright as the light filtering through the upper part of the ocean. Even cooler is that they move around by what's essentially underwater jet propulsion. Here's a video of one in action, if you're curious.
As for octopuses, well, there's a huge variety of them around! Sure, they've all got eight legs and two eyes, but with over 300 recognized species around, there's an immense amount of interesting behaviour and looks that they can show. In today's post, you'll notice one of them that looks suspiciously like a nautilus. That's an Argonaut, but some people call them Paper Nautiluses. The shell around them isn't actually a shell, as much as it is a paper-thin covering that the female octopuses make just before they give birth, and can later be discarded. No one's fully certain how they evolved to do that, but it's fascinating behaviour anyway. You'll also notice a blanket octopus- but that one doesn't always look like that! This video shows the process of the blanket unfolding. It's really very fluttery and pretty.
But that's enough talking from me, so on to the animals.
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OCTOPUSES
coconut ocotpus
blue ringed octopus
argonaut / paper nautilus
blanket octopus
mototi octopus
wunderpus octopus
And of course, spiders!
Today's spider might not look very impressive. He's a grubby little thing, but looks can be deceiving!
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This one- and the other two below- are spiders from the Portia genus. They stand out from other spiders because of their hunting behaviour. Unlike many other jumping spiders, which will just chase down and leap on bugs happily, Portias are... well, spider hunters. Not jumping spider hunters, but web-building spider hunters, which is where the fact that they look like a tiny piece of dead leaf and twigs comes into play.
The spiders they hunt are almost always larger than they are, so Portias have to be smart and use trickery. What they do is to find a corner of a web and then start tugging on it, mimicking various patterns that a struggling insect would give off, and by doing that lure the spider that owns the web to it. They've even been seen to do this for days on end. When the other spider approaches, they back off, find an overhanging spot, then deliver spider death from above.
Their behaviour is especially remarkable because lab studies have shown that it's adaptive rather than purely instinctive- that is to say, put in a position against artificial spiders and webs, Portias alter their own web-tugging behaviour until they get some sort of response. They can also hunt other jumping spiders, but trick tose by pretending to be bits of leaf litter. Interesting, aren't they?
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But first, a quick introduction to these interesting animals! Nautiluses have been called living fossils, which is definitely a fitting title for them as they haven't changed in literally millions of years. Even though they might not look much like squid, they share similar heads and tentacles to them- but unlike squid and octopuses, can have dozens and dozens of tentacles poking out at a time. And VERY unlike squids and octopuses, they have shells, which grow up along with them. If you've ever picked one up in real life, you'll notice that the top is usually banded and the bottom is white. There's a reason for this! It's because when the nautilus is upright in the ocean, animals looking at it from above see it as the same shade as the water below, and animals looking at it from below see it as bright as the light filtering through the upper part of the ocean. Even cooler is that they move around by what's essentially underwater jet propulsion. Here's a video of one in action, if you're curious.
As for octopuses, well, there's a huge variety of them around! Sure, they've all got eight legs and two eyes, but with over 300 recognized species around, there's an immense amount of interesting behaviour and looks that they can show. In today's post, you'll notice one of them that looks suspiciously like a nautilus. That's an Argonaut, but some people call them Paper Nautiluses. The shell around them isn't actually a shell, as much as it is a paper-thin covering that the female octopuses make just before they give birth, and can later be discarded. No one's fully certain how they evolved to do that, but it's fascinating behaviour anyway. You'll also notice a blanket octopus- but that one doesn't always look like that! This video shows the process of the blanket unfolding. It's really very fluttery and pretty.
But that's enough talking from me, so on to the animals.
source
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source
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OCTOPUSES
coconut ocotpus
blue ringed octopus
argonaut / paper nautilus
blanket octopus
mototi octopus
wunderpus octopus
And of course, spiders!
Today's spider might not look very impressive. He's a grubby little thing, but looks can be deceiving!
source
This one- and the other two below- are spiders from the Portia genus. They stand out from other spiders because of their hunting behaviour. Unlike many other jumping spiders, which will just chase down and leap on bugs happily, Portias are... well, spider hunters. Not jumping spider hunters, but web-building spider hunters, which is where the fact that they look like a tiny piece of dead leaf and twigs comes into play.
The spiders they hunt are almost always larger than they are, so Portias have to be smart and use trickery. What they do is to find a corner of a web and then start tugging on it, mimicking various patterns that a struggling insect would give off, and by doing that lure the spider that owns the web to it. They've even been seen to do this for days on end. When the other spider approaches, they back off, find an overhanging spot, then deliver spider death from above.
Their behaviour is especially remarkable because lab studies have shown that it's adaptive rather than purely instinctive- that is to say, put in a position against artificial spiders and webs, Portias alter their own web-tugging behaviour until they get some sort of response. They can also hunt other jumping spiders, but trick tose by pretending to be bits of leaf litter. Interesting, aren't they?
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