So the spokes on the wagon wheel and the outer framework here, that's all the dragline silk. It's called major ampullate silk if you want the fancy word. - The major ampullate is that one that commonly compared to steel?
It's called major ampullate silk if you want the fancy word. - The major ampullate is that one that commonly compared to steel? - Yes! - Okay.
Because none of them can produce major ampullate silk. And major ampullate silk is that drag line silk. Still, even though none of them can do that, there are 90 known species of the mesophiles.
None of this kind of silk is stronger than steel. So major ampullate silk, that's what they hang on. That's what allowed spiders to move out into the air space.
And you can see where that allows spiders to go to-- they've created this completely new niche, right? So major ampullate silk, it allows you to drop out of harm's way. That's probably its biggest benefit.
It'll find a high point, go on the tips of its legs, and then put its hind end up into the air and start releasing major ampullate silk. And it can actually sense air currents on the bristles on its body.
And so what they do is they dive down from the surface. They construct a major ampullate silk sheet. Then the silvery stuff on the spider's body, those are air bubbles adhering to the bristles on their body.
There are about 5,000 known species of jumping spiders. of-- the major ampullate safety line coming from the back of the spider.
None of these spiders that we've looked at so far can do that. Because none of them can produce major ampullate silk. And major ampullate silk is that drag line silk.
There are about 5,000 known species of jumping spiders. They can also use the major ampullate line to kind of control their direction as they come close to their target.
So technically, that's spinning. So it will spin these lines-- these major ampullate lines. Because of the tensile strength of the lines, you can see that this, compared to anything you've seen previously, has a lot more space
known as the araneomorphs. They can all make this silk that I'm talking about, which is called major ampullate silk. This is the silk that you hear about when you hear about spider silk being stronger than steel.
The lines deter its predators. But the biggest advantage, and probably the reason leading to the evolution of major ampullate silk, is that if things get too hairy with the predator, they can dive out on their safety line.
So it allows you to-- oh, now, the powder here is adhering to another araneomorph innovation called cribellate silk. So the araneomorph spiders will lay down the major ampullate catching lines, and at the same time, they have a spinning organ called a cribellum that emits tiny fibrils of silk.
There are about 5,000 known species of jumping spiders. So all of these ways of negotiating with the environment are in different ways enabled by major ampullate silk.
There are about 5,000 known species of jumping spiders. Probably most the time, they don't hit their target, but they're saved by their major ampullate line.