Recent content by yerpo

Anyone?

As I https://www.physicsforums.com/showthread.php?t=283482", I'm struggling with physical basics of vibration in rods as a non-physicist. If someone would be kind enough to explain in simplest possible terms, I would like to understand two things: 1. What is the relation between standing...

Looks like I didn't explain what I meant clearly enough. Let's try again: I have half a second long pulse with 100 Hz frequency, traveling at velocity of approx. 75 m/s along the plant stem. If I induce vibration at the top and detect vibrations 50 cm above the ground (somewhere below the top)...

I'm familiar with the work of Cocroft's group, thanks. Their system is a bit different, though, because the little buggers they study communicate using higher frequencies that don't transmit as effectively as low frequencies that our buggers use. Plus, they're smaller. The thing you said about...

I'm resurrecting this thread because I am still not any closer to the solution, so please bear with me. I tried what Skeleton proposed and determined the first harmonic. On a 83 cm tall stem, the period is almost exactly 1 second (around 980 ms, to be precise). But putting this value in the...

Actually, that was the image conjured by those who were desperate to sell a warehouse of vaccine that makes you wonder whether you'd be better off getting sick from the flu.

I wasn't saying that.

If I had to guess, it influences the expression of genes that control axon formation.

That is not completely true. There are songbirds, such as the chaffinch, whose repertoire is largely inherited. Feedback from other birds still has influence, but even if it was in complete isolation from the beginning of his life, a male chaffinch could produce a song recognized by a female...

All of them, by definition.

The situation can be a bit more complicated in such large molecules as proteins, because it can have regions with sequences of differently charged aminoacids.

What you're discharging doesn't necessarily have to include sperm cells. If the bacteria have been messing with your prostate, then it could just be the fluid.

This is a standard misconception that probably stems out of creationist's fallacious arguments against evolution. A complex instinct didn't just randomly spring into existence in a couple of individuals after which those individuals were selected, but the instinct itself gradually evolved from...

I'm not sure about your regression line. I left out point zero deliberately, because it's recorded directly opposite of the shaker, which is fixed and cannot oscillate freely, so it more or less registers its movement.

You mean like this? This is getting more interesting by the minute. Although I still can't see the 40 cm wavelength - it's closer to 30 than 20, but still... Please correct me if I got it wrong. I'm afraid the stem is too weak to stand upright by itself when the plant is this tall, but...