Cave Acoustics

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Re: Cave Acoustics

Postby hiflier » Jan 21, 2016 6:38 pm

OK, back on topic. Whew, thought I was a goner there for a minute. The micro rabbit holes can really sneak up on a person ;) Any way to perhaps best illustrate my point I would say that I am wondering if caves can act as megaphones or parabolic ears. I guess basically that the dynamic I'm trying to nail down. I know that unless either quality is truly enhanced then even if someone notices it might not be remarkable enough to mention? And yes, if the group doing this research is here, or still has a member here It would be good to talk to them about this. I would like to start a short thread on critters sometime soon too. Not troglodytes per se (although they are totally interesting) but the critters that visit caves, spend the night or not, and how you know they've been around........later for that though. For now think Megaphone/Parabolic ear and in your excursions- once inside check on sounds from outside (mega-ear)? Muted, enhanced, no different. Same thing when outside with someone inside. Inside voices easier to hear (megaphone)?
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Re: Cave Acoustics

Postby caverdan » Jan 22, 2016 11:17 am

Welcome to the forum, hiflier.

The first crawl way, corner or bend in a passage would dissipate sound, not enhance it. he would have to be in an entrance with the shape of a megaphone in order for your theory to work.....me thinks. More than likely we are talking a shelter cave. I would think that any cave with a large enough entrance to reverberate sound in Oklahoma is a known cave. Larger cave openings bring people. Small crawly opening don't reverberation or collect sound. Just because a big room inside a cave has really good reverberation to it, doesn't mean you can hear it past the first bend in the passage. An example of this would be the speak eases that you would find in caves during prohibition. Most are now tour caves.

Sasquatch would have to have some way to see the bats in order to collect them from a hibernation site. This would go for him exploring much past the twilight zone. for example, Bats use sonar, Rats use urine trails, and Madrats use Manley lights. (Shameless plug for two friends that make and sell a most awesome light http://www.marblemountainlights.com/Manley20_Flyer.pdf)

Any theories on how he/she can see in total darkness?
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Re: Cave Acoustics

Postby hiflier » Jan 22, 2016 5:55 pm

Thanks for the welcome. I have to say I'm extremely surprised at the responses here. But I sense that you get where I'm going with this and why and that perhaps you can see that I'm not at all prone to wild speculation- other than that of Sasquatch as an animal itself I mean; which is certainly as wild as it gets for me anyway. Thanks for the information regarding corners and bends and I'll note that as I pursue this line of thinking. My friend in Oklahoma that I spoke to on the phone is on a large area of private land whose landowner has given permission for him to explore for such purposes. I had asked him about talking to the landowner to see if he had given permission to any grotto or cavers to check out the caves and the answer was no.

My friend is part Native American and is trying to work with the local NA's regarding his search for bones or burial sites which are sensitive places to Native Americans both spiritually and ancestorally. This is going about things in the most correct, proper, and respectful way as far as I'm concerned and I've encouraged him to look at the caves. He was the one who actually brought up the idea and says he's convinced that the cave systems in the Kiamichi Mountains are active but at the same time extremely remote as far as access.

As far as Sasquatch seeing of finding it's way in the dark...um....I don't think you may be ready for that one but I can say one thing about what witnesses have said. It has to do with what science calls the Tapetum Lucidum. It's the membrane at the back of an animals eye that causes it's eyes to reflect light. We see the phenomenon in cats, dogs, deer, raccoons, and many other creatures that are either only nocturnal or diurnal (active both day and night). This membrane captures light a that the retina collects and reflects it a second time inside the eye and enhances the image the eye picks up by adding light to it. Nature is pretty remarkable, eh?

So that's one idea for seeing in the dark because witness describe this quality called eye shine in many reports of night time encounters. But here's the thing. Primates including the Great Apes and Man do not have this membrane except for some Lemurs in Madagascar so one of the questions has been how would such a feature get into the Sasquatch ancestry in the evolutionary sense? Too much for this thread to go into but there's one more point to make. Some new thinking has suggested that ancient Humans, even as recent as Neanderthal, may have used a very sensitive technique of echolocation as well similar to bats but of course in much lower sonic registers. Be that as it may between having good night vision along with possible ancient echolocation then getting around in a cave might not be too difficult as long as it's only a couple of hundred feet or so?

Then too some animals follow urine trails because they see the urine in the ultraviolet spectrum. some animals can see in the infrared spectrum too which if a bat colony gives off heat (and it does) than between the smell and the heat they could be located. I've often wondered about thermal imaging in caves though the units are prohibitively expensive. An iphone app I saw once can be had for around $300 but the resolution isn't that great. I think it could still be a valuable tool for you cavers though?

I've been gaining such great info from you folks and I have expressed my hope that I would be able to give back so I hope this counts. BTW your friends' light is really tops! Just might have to pick one up. Go another friend in NH who want to have me look at a couple of mine-type caves sometime in May and my goal is to learn how not to die in one first :doh:
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Re: Cave Acoustics

Postby caverdan » Jan 22, 2016 8:00 pm

As far as Sasquatch seeing of finding it's way in the dark...um....I don't think you may be ready for that one but I can say one thing about what witnesses have said. It has to do with what science calls the Tapetum Lucidum. It's the membrane at the back of an animals eye that causes it's eyes to reflect light. We see the phenomenon in cats, dogs, deer, raccoons, and many other creatures that are either only nocturnal or diurnal (active both day and night). This membrane captures light a that the retina collects and reflects it a second time inside the eye and enhances the image the eye picks up by adding light to it. Nature is pretty remarkable, eh?
I understand what your talking about, but in order for that to work, you need some type of light....be it very small.....in order for that to work. Unlike the movies.....caves contain what we call....total darkness. We're talking dark room dark. Black as the eye can't see.

My friend is part Native American and is trying to work with the local NA's regarding his search for bones or burial sites which are sensitive places to Native Americans both spiritually and ancestorally. This is going about things in the most correct, proper, and respectful way as far as I'm concerned and I've encouraged him to look at the caves. He was the one who actually brought up the idea and says he's convinced that the cave systems in the Kiamichi Mountains are active but at the same time extremely remote as far as access.
I can truly appreciate that fact and I had forgotten about the reservations in Oklahoma. That would explain why large cave entrances would be seldom visited or known about. Worth looking into if you can swing the access. It's not uncommon to not allow access to cavers including the NSS.

If you search our forum you will find threads on infrared cameras and thermal imaging in and around caves. Good luck in your quest for knowledge.
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Re: Cave Acoustics

Postby hiflier » Jan 22, 2016 8:40 pm

You are absolutely on point- there needs to be some light for the membrane to work. Some of the research science has done on the adaptation is to understand not only the make up of the membrane as far as cellular or in some cases even crystalline but to also determine if different light sources change the reflected color. For instance incandescent light may reflect a different wavelength than halogen and so the eye shine color would be different. It's kind of fascinating really.

Oklahoma's history regarding Native Americans is not a pretty one. Over 70 different tribes were moved there in the 1800's early 1900's. I'm not a Native American but stuff like that really isn't about ethnicity. It's about how one Human Being treats another Human Being.......and greed. Sad tales all around. Thanks I will search the forum which is a goal in being here.
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