Physics Assignment: Snake Hearing

[Daniel Humm]

Hi guys, my girlfriend has to do an assignment in Physics on snake hearing and was wondering if any budding physicists or herpers would be able to assist...!

Specifically, the essay will cover how snakes hear, how vibrations are passed through materials and the physics behind sound. I also have to answer the question, "Can snakes 'hear' on the moon?"
There is an article that I would love to get my hands on, Snake bioacoustics: Toward a richer understanding of the behavioral ecology of snakes by Bruce A. YOUNG (from The Quarterly review of biology, 2003, vol. 78, no3, pp. 303-325 ).

So...if anyone has any useful links, articles, or information on the physics behind snake hearing, feel free to share it. (If the information is yours it will be referenced appropriately). Thanks in advance...
Corinne

[lozza]

Is it a high school physics assignment?

I might have a few things - pm me your email address

[mines bigger]

if it is high school physics have a talk to slim6y

[Forensick]

hahhahaha!

my GF is doing that atm for uni physics

[slim6y]

Sounds like fun...

All I can relate this too of course is high school physics (I teach it yay)....

But... Sound travels jolly fast through solids - and as snakes hear with thier feet, they're sitting on solids.

Therefore vibrations are travelling up to 5000 m/s - this is much faster than sound travelling in air of course 330 m/s on an average day.

For a human tho, the problem comes from not knowing which way the direction of the sound came from. For example divers have trouble in water because sound travels at close to 3000 m/s.

Putting your ear on a railway track is all very good - you can hear a train coming because sound in steel travels at 5000 m/s (thereabouts - forgive me on symantics) but try telling which way the train is coming from...

I wonder if the snake can tell direction by where the sound hits the body - or if they really care - because the scent will tell them direction anyway...

Interesting... when you're finished can you post me a copy of the task sheet etc - I might be able to use it in school

Have fun!

[cris]

Snakes have feet?

[slim6y]

Mine do - i know some people cut them off - but I leave mine attached... geeez cris....

[Duke]

I have access to quite a lot of science journals and articles.
I'll post stuff when I get home If I remember.

Sound pases through objects like a slinky wave. Air molecules are normally vibrating. When a sound is travelling in the air the molecules bounce off each other continuing the sound wave. They don't move very far. They get hit, bounce into another molecule, and transfer the energy on.
Same with solids. Except much faster because the atoms or molecules are packed much more closely.

For a very good understanding of the physics behind sound see
http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html

Snakes would be able to hear on the Moon, because as said before they hear vibrations in the ground. Provided the sound originated from the ground, or at least on top of it, the sound will propagate through the ground to the snake.
If it's floating in the air it won't hear anything due to lack of atmosphere and a medium for propagation.
If I was standing on the moon and shouting at the top of my lungs, the snake won't hear it due to poor transfer of the sound through my bosy and into the ground.
You'd also have to look at how dense the moon's surface is.
If it's lightly packed, like fresh snow, the snake would have a poor time hearing, even through the ground.
But if it's harder, like soil or rock, then it's hearing range increases.

You also have to keep in mind that sound energy diminishes the further away it gets. Sure sound travels at kms at a time per second in solids/liquids, but if it's really far away you still won't hear it.
The atomic collsions I mentioned before, aren't purely elastic. Energy is lost as heat the further it goes, and also the concentration of energy decays too. Like a ripple in water. The further away it gets, the more spaced out the rings get.
slim6y, would sound in the ground's surface follow the Inverse Square law? Or is that only for three dimensions? I'm sure there's still a relationship for a psuedo one-dimension situation of sound on the surface.

[Daniel Humm]

Its for Uni physics (first year though, so that is pretty much year 12 physics). Thanks Duke and slim6y for what you've said so far! I've never done physics before so what are the basics for you, aren't for me...
slim6y, there isn't a task sheet as such, we just had to do an essay on something 'physics' - the lecturer basically gives you an idea based on your hobbies/interests, and off you go. Hence why I had to find out if snakes could hear on the moon

I thought snakes could only hear via vibrations - seems this isn't true :

"Thus, like many other animals, snakes have two ways of detecting sounds: earthborne and airborne. The earthborne vibrations are passed through the belly muscles to special receptors along the spine and thus transmitted to the brain. Airborne sounds are transmitted to the lung from the skin receptors to the eighth cranial nerve and inner ear.
Most snakes can hear a person speaking in a normal tone of voice in a quiet room at a distance of about 10 feet (3 m)."
From http://www.anapsid.org/snakehearing.html. That article I mentioned before goes into greater detail on this and seems to be the best source of info for the latest research on snake hearing.

But for the purpose of this essay then, yes the snake would be able to hear earthborne sounds on the moon, but not airborne.

[slim6y]

essay a bit easy by the sounds of things really... something my year 11s would do perhaps!

Maybe talk about the sensory organs and their location... aaaaarg I don't know

Sound only travels longitudinally and requires atoms as a transfer of the energy - so you got all that sorted easily enough... but the moon does have an atmosphere, even if it is very very small! Don't know about sound tho... probably no good

So if you were in outer space, would you hear your self scream internally???

[Duke]

According to the following link, the "atmosphere" of the moon is just stuff that either leeches out of the ground or falls on the surface. The solar winds carry away what is there quite frequently.
http://www.windows.ucar.edu/tour/lin....html&edu=high
My assumption is that you wouldn't hear anything.

If you had a lung full of air, and didn't explode from the weak atmosphere... I reckon it'd be a bit like screaming under water. You'd feel it come out, "hear" it in your throat...
Sorta like when you cover your ears really tightly, and start singing "I'm not listening.." You hear it in your head, but not the sound that comes out of your mouth and is reflected back.

[Forensick]

daniel, latrobe?

[Daniel Humm]

Yes La Trobe but its not me, its my girlfriend and thanks everyone for helping her out ...

[Forensick]

ha!

the levturer guy has no imagination, my GF is doing the same assignment