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Plants can detect sound

economist.com

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Re: Plants can detect sound

#111

Post by zelphirkalt »

yyyk wrote: post #50
zelphirkalt wrote: post #18

Earlier quoted context omitted.

Similar to a question I had in physics class at school, which was quickly brushed aside by the teacher, who wanted to continue with the content: Why is temperature one of the base units? Isn't temperature just movement as well? Nowadays I know I was more or less right. Just that 1 molecule moving hardly makes temperature and one probably needs a large number.

- The average movement of a solid is often zero, while its temperature is usually higher. - Movement has an implied direction even if we ignore it sometimes. Temperature does not. - A gas molecule can move a lot but have low temperature because it has little to collide with. It's more accurate to talk about vibration/collisions rather than movement.

My idea back then was: What is vibration, other than movement of tiniest particles? But yes, maybe collision is what actually makes the temperature? Lets assume all the molecules where moving like they usually do, but for some insignificantly small chance, they do have no collisions for a few seconds. Would the object have a temperature?

Re: Plants can detect sound

#112

Post by yyyk »

zelphirkalt wrote: post #111
yyyk wrote: post #50

Earlier quoted context omitted.

- The average movement of a solid is often zero, while its temperature is usually higher. - Movement has an implied direction even if we ignore it sometimes. Temperature does not. - A gas molecule can move a lot but have low temperature because it has little to collide with. It's more accurate to talk about vibration/collisions rather than movement.

My idea back then was: What is vibration, other than movement of tiniest particles? But yes, maybe collision is what actually makes the temperature? Lets assume all the molecules where moving like they usually do, but for some insignificantly small chance, they do have no collisions for a few seconds. Would the object have a temperature?

>What is vibration, other than movement of tiniest particles?

Imagine a pendulum, moving back and forth. The average movement is zero! Even for different pendulums moving at different speeds. Vibration is a similar case.

Obviously movement is not the most useful way to examine these systems, we want to look at other things too. Temperature is a measure of the kinetic energy involved.

>maybe collision is what actually makes the temperature

Kinetic energy is involved in both collisions and vibrations.

>but for some insignificantly small chance, they do have no collisions for a few seconds

We can compare to atomic fission, where the fission is also probabilistic - but the result is very predictable.

Re: Plants can detect sound

#113

Post by pvaldes »

skeaker wrote: post #110
pvaldes wrote: post #109

Earlier quoted context omitted.

> How do you explain the difference in growth rate under controlled conditions, then? There is not a lack of candidates: Riding the academy game (plants must be sentient now, just because this is where the money is now), pure luck (moving more of the better genetics to one group just by random), cherry picking (The experiment results were publishable the 49th time, pffew), or giving your greyhound a helping hand with…

> Riding the academy game (plants must be sentient now, just because this is where the money is now), pure luck (moving more of the better genetics to one group just by random), cherry picking (The experiment results were publishable the 49th time) or giving your greyhound a helping hand (and faking the results). Choose one, there are much more other coming. In other words, "they are liars," "they did not account for…

In other words,

1) "what is not funded in science doesn't exist",

2) "sometimes you obtain the desired result by luck or rogue factors that are unrelated with your desired explanation" Speakers have big magnetos, for example. Other team could repeat exactly the same experiment and conclude that "magnetic forces stunt grow".

3) "sometimes only the 'correct' results can be published, so people repeat the experiment until being convinced of their results"

and 4) "yes some scientists are liars"

I will add a 5) you may favor desirable events and ignore undesirable ones without even realizing it (provide better care to one group, water for a few seconds more each day or have two different people caring for different groups)...

... Because unplanned events and lab accidents happen. I assume that having big speaker boxes near plants may trow a temporary shadow on them each day. If it happens in your lunch hour you could never realize it. And this things happen in science. All the time.

I would suggest to put a couple of turned off speakers of the same size near the quiet group and repeat the experiment.

Re: Plants can detect sound

#114

Post by kilolima »

saberience wrote: post #106
kilolima wrote: post #38

Earlier quoted context omitted.

I think Annihilation is more a shameless remake of Stalker, as far as going into a "Zone" where an alien influence has changed the nature of reality.

I thought Annihilation is more of a re-thinking of HP Lovecrafts story "The Colour out of Space". You should totally read it, it's fantastically creepy and clearly influenced the film.

Yes! I think you're right. That's a great connection, never thought of Annihilation in that way. "Color out of Space" is the first HPL story I ever read, and still one of my favorites.

Re: Plants can detect sound

#116

Post by goodbyesf »

noman-land wrote: post #14

This may sound like a dumb question but can anyone explain to me why our senses are not all just considered touch? Molecules touch your tongue and you taste things. Molecules touch your nose and you smell things. Air vibrates your inner ear hairs and you hear things. Photons hit your eyes and you see things (not sure if this counts but it seems like it could).

> Molecules touch your nose and you smell things. Air vibrates your inner ear hairs and you hear things. Photons hit your eyes and you see things (not sure if this counts but it seems like it could).

You can see things in the dark with your eyes closed, you can hear things in a vacuum sealed isolation chamber, you can smell things without any there being anything smelly and you can feel things without touching anything.

Rather than every sense being touch, every sense seems mental.

Re: Plants can detect sound

#117

Post by _el1s7 »

noman-land wrote: post #14

This may sound like a dumb question but can anyone explain to me why our senses are not all just considered touch? Molecules touch your tongue and you taste things. Molecules touch your nose and you smell things. Air vibrates your inner ear hairs and you hear things. Photons hit your eyes and you see things (not sure if this counts but it seems like it could).

Don't confuse the word touching, or when two things get in contact, with the actual human sense of "touch".

You don't smell and see through your hand, do you...

Re: Plants can detect sound

#118

Post by ChainOfFools »

unsupp0rted wrote: post #59
qlm wrote: post #54

Boquila trifoliolata appears to mimic surrounding leaves and the mechanism is currently unknown. One (controversial) hypothesis is that it has some sort of vision. https://en.m.wikipedia.org/wiki/Boquila

> One hypothesis is that volatile organic compounds emitted from host plant leaves induce a phenotypic change in nearby B. trifoliolata leaves. By receiving different host signals into its system, it is able to create specific signals and hormones in its tissues to regulate gene transcription of leaf morphology and developmental pathways for leaf differentiation.[12] The other hypothesis is that there could be horizo…

shadow patterns and reflected light from nearby leaves or leaf- like bits of plastic as signals perhaps?
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