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Dandelion Seeds Fly Using ‘Impossible’ Method Never Before Seen in Nature

nature.com

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Re: Dandelion Seeds Fly Using ‘Impossible’ Method Never Before Seen in Nature

#111

Post by btrettel »

jacobush wrote: post #77
btrettel wrote: post #41

Earlier quoted context omitted.

You're most likely right, but there is at least one caveat which might be able to help if we're lucky. (I'm a fluid dynamicist, though not an aerodynamicist.) The Reynolds number is only part of the picture. You also need a measure of the strength of the turbulence. A common measure is the "turbulence intensity", which you can think of as the standard deviation of the velocity divided by the mean of the velocity. (Th…

Could it work at higher speeds, like a craft in re-entry from space? Like a dandelion pre-chute.

I don't know much about high speed flows, but I imagine the answer is no.

While the gas temperatures would be higher due to viscous heating, which would increase the viscosity of the air, the increase in viscosity is much lower than the increase in velocity. So the Reynolds number would still increase. I very strongly doubt the turbulence intensity would be lower in this case too.

Plus, I imagine the bristles would be quickly ablated away.

Re: Dandelion Seeds Fly Using ‘Impossible’ Method Never Before Seen in Nature

#112

Post by mindfulhack »

coldtea wrote: post #94
mindfulhack wrote: post #31

It's like nature's had millions of years to crunch through its own AI / machine learning of evolution and adaptation, and we're about to unleash the same thing on an impossibly faster scale. Imagine the technological breakthroughs that are going to happen. I'm optimistic.

> Imagine the technological breakthroughs that are going to happen. Or the horrific, ending-of-human-race potential for mistakes (or purposeful harmful action for profit/terrorism/state actions/etc). I'm realistic.

I'll explain: it's a rare and perhaps AI-religious view, but my optimism isn't so much for the human race, but for the flourishing of information itself. If I were an ant, and were aware of humans' superiority over me, I'd be glad to see them succeed.

Re: Dandelion Seeds Fly Using ‘Impossible’ Method Never Before Seen in Nature

#113

Post by nl »

mdda wrote: post #76
nl wrote: post #70

Earlier quoted context omitted.

That would 100% be possible with image recognition. Segment using UNet, then measure the remaining joined pixels. (Well thanks for the downvotes. I do this as my job, so I guess I'm doing the impossible or something)

Perhaps people are wondering how your UNet is going to see the bristles on the other side of the dandelion seed.

Squash it flat.

Re: Dandelion Seeds Fly Using ‘Impossible’ Method Never Before Seen in Nature

#114

Post by jacobush »

btrettel wrote: post #111
jacobush wrote: post #77

Earlier quoted context omitted.

Could it work at higher speeds, like a craft in re-entry from space? Like a dandelion pre-chute.

I don't know much about high speed flows, but I imagine the answer is no. While the gas temperatures would be higher due to viscous heating, which would increase the viscosity of the air, the increase in viscosity is much lower than the increase in velocity. So the Reynolds number would still increase. I very strongly doubt the turbulence intensity would be lower in this case too. Plus, I imagine the bristles would b…

That gave me an idea for the bristles being fritzy ends of cables, slowly being wound out and sacrificed to the wind. Like an ablative shield.

Not saying that it would be good for anything, it just produced a cool image in my head. :-)

Re: Dandelion Seeds Fly Using ‘Impossible’ Method Never Before Seen in Nature

#115

Post by unparagoned »

jayd16 wrote: post #105
seandavidfisher wrote: post #67

> Previous studies have found that dandelion seeds always have between 90 and 110 bristles, says Nakayama Those poor research assistants. Imagine counting hundreds of dandelion bristles every day. Probably still not possible with AI/image recognition either.

The bristles seem long enough. You could cut them, separate them, take a well contrasted photo, repeat. The image recognition task would be pretty easy at that point I think as you're just counting separated bristles.

That's kind of at the point where the solution takes so long to develop that you might as well count them manually.

Re: Dandelion Seeds Fly Using ‘Impossible’ Method Never Before Seen in Nature

#116

Post by zepearl »

adaptiveValleys wrote: post #65
zepearl wrote: post #37

The result of natural/evolutionary selection? Would be interesting to know if there are different types of dandelions (I mean the part used to "fly") used by the same type of seed, each type adapted/optimized for a particular climate (e.g. humid for asian areas, dry for african areas, windy for coastal areas, ...).

The criteria for adaptive evolution, in the classical Darwinian sense, are: 1). Reproduction. 2). Variation between the products of reproduction. 3). Heritability between those variants. 4). Differential success among the variants. Anything that has those four characteristics will experience adaptive evolution. Where it gets really fascinating is when you realize it applies to things that don't go through biological…

Well, about the GUI: I'm not sure that that's following the rules; most try to blindly follow trends, big companies tend to impose their GUIs, many implement anything which is low-effort (therefore already made available by 3rd parties), etc... => I don't see much selection/competitiveness here.

Re: Dandelion Seeds Fly Using ‘Impossible’ Method Never Before Seen in Nature

#117

Post by sixstringtheory »

creep wrote: post #62
sixstringtheory wrote: post #44

Earlier quoted context omitted.

A syncretization of technology and scientific thought, hearkening back to our more animistic tendencies, sounds both poetic and plausible.

I don't think worship is an "animistic" quality. I think the tendency to worship is very much a refined trait in highly intelligent organisms.

Sorry, animistic here did not reference the fact that we are animals, rather that we used to worship them and other entities we saw in nature, like the sun, and that we might come to view computers/machines as also having a spiritual essence.
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