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Plants can detect sound

economist.com

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Re: Plants can detect sound

#13
post #7

I won't be surprised if single cell organisms, even prokaryotes can detect and react to sound - just a matter of more research to find out how.

> I won't be surprised if single cell organisms, even prokaryotes can detect and react to sound

It would have to be pretty insanely high in the ultrasound. A 30 kHz (above the top of usual audible sound range) wave is around 10 mm (10000 µm) in wavelength; a typical prokaryote is of order 1 µm. While there are some uses for MHz-scale ultrasound, the attenuation starts getting pretty insane -- there's just not much energy at the scale of gigahertz sound to detect.

Re: Plants can detect sound

#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).

Re: Plants can detect sound

#15

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).

I think collision or interaction are better words. The word touch is meant for bigger objects, like hands, animals, furniture, fabrics, not molecules and electromagnetic radiation.

Re: Plants can detect sound

#16

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).

Isn’t touch a biological pressure sensor though? Could be similar to hearing, sure, but taste, smell and sight are definitely more like chemical and electromagnetic sensors.

Re: Plants can detect sound

#17

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).

If you want to get that reductive, ultimately everything in the universe is just particles and forces and interactions between them, and any concepts beyond that are arbitrary lines drawn by us humans in an attempt to organize the chaos.

In the case of senses, it's about perception. We perceive the signals from our retinas differently than the ones from our fingertips, so we give them different names (sight vs. touch).

There are also differences in the "hardware" -- sight and touch signals start with different kinds of receptors, travel down different nerves, and are processed in different parts of the brain -- but the hardware differences don't map 1:1 to the way that we categorize senses. For example, pain and pressure are processed by entirely different types of receptors, but we still call them both touch. On the flip side, balance and hearing share a lot of the same hardware, but we consider them to be different senses.

Re: Plants can detect sound

#18

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).

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.

Re: Plants can detect sound

#20

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).

Touch is measuring motion or sustained pressure. Taste doesn't care about how hard the molecules hit your taste receptors, only if they bind to the taste receptors or not. Our eyes don't measure the photon pressure[1], the photons react with the atoms in our photoreceptor cells[2] triggering an electrochemical process.

Our sense of hearing is the closest to touch. We have hairs on our body which is part of our sense of touch, which react to motion and pressure, both from physical objects and the air around us.

Similarly the hairs in our ears react to the pressure waves of the air around us. However a big difference is that they're shielded by the ear drum and don't react to sustained pressure, only relatively high-frequency air pressure changes.

Why we call them different things is mostly because they're used for different tasks. An electrical generator and an electrical motor can be the same thing, it's just what it's used for.

[1]: https://en.wikipedia.org/wiki/Radiation_pressure

[2]: https://en.wikipedia.org/wiki/Visual_phototransduction

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