lunaskye0 said:
thank you, i appreciate your response!
that does sound kind of interesting, but I'm not sure I would want to do something like that. But the idea of sound underwater sounds really cool... hm, I'll have to think about it. Maybe something broader, towards all sea creatures and their differences? How is this related to medical physics though? (maybe that is a dumb question)
Didn't you ever hear of an ear, nose, throat specialist ?-)
Didn't you ever hear of a vetrinarian?-)
These are both types of medical doctors.
This is a study of a mammals ear. The structure resembles the human ear in some ways, but differs in others. Some of the techniques that you learn may be applicable to human ears.
Okay, the ossicles of whales are fused. However, doesn't that happen in old people too?
Okay, the middle ear is detachable in whales. However, that just makes it more convenient to work with.
You are young. However, you will learn that "broad" is "bad". There should always be fewer degrees of freedom in a system than parameters that can be varied. One can not come to a sensible conclusion if one tries to vary hundreds of parameters at once.
There are millions of different species of sea animals, with about a hundred different organs for each species and about a dozen stages of life for each organ.
You only have three physical parameters to vary: frequency, phase and input amplitude. The fewer degrees of freedom your system has, the easier the experiment will be.
If you start getting good results with one species of animal, then it will be time to branch out. However, you really should get a handle on one system before you approach others.
lunaskye0 said:
I was also thinking maybe something like how sound seems to be smothered or deflected, and what is the best way to receive a range of frequencies, and how different atmospheres/room shapes affect the qualityy of sound?
The atmospheric system is complex but not novel.
The atmosphere varies a great deal. There are an infinite number of possible weather conditions. Weather conditions are never 100% reproducible. There are an infinite number of possible room shapes.
But worse, lots of scientists have looked at that already. For example, there is a lot of research on how sound propagates in the atmosphere. There are hundreds of defense scientists who have been working decades on how sounds propagate in the atmosphere. The acoustics of stage and concert hall have been studied at least 2500 years.
The nice thing about a whales ear is that the topic is far more narrow then what you are talking about. The middle ear of a whale varies with both the species and the age of the whale. However, it is reproducible. There are only 144 species of whale. I am sure that the middle ear of adult whales in the same species are pretty much the same. You can repeat your experiments because you have a larger ensemble of nearly identical samples.
The cranium varies too. With other mammals (e.g., human), the rest of the cranium varies. This can effect transmission of sound in the middle ear. However, with whales the middle ear is detachable from the rest of the cranium. So you don't have to worry about variation in craniums.
A whales middle ear is filled with a waxy substance. You can fill the cavity, if you wish, with any waxy substance. Or, you can fill the middle ear with dry air. Whatever you place in the middle ear would be much more reproducible than weather conditions.
You can make a decision to work with one species of whale at one stage of life using one medium for filling up the middle ear. That is three variables that you can fix in you experiment. You can attach the microphones right on the middle ear. With whales, you don't have to be concerned about the rest of the cranium.
By the way, I have a suggestion for you. I think the beaked whale is the species of most interest with regard to sound. However, maybe you want to consider the experimental convenience.
The easiest experiments that you can do would be with the Tursiops truncatus (the blue nose dolphin). Tursiops is the most common dolphin in aquariums and dolphin shows. When one of these dies, they regularly send one to a museum for necropsy. Usually, the oldest Tursiops die. So the largest number of skeletons available for study would be from adult Tursiops truncatus. Because they are so common, museums are more likely to lend you some middle ears of adult Tursiops truncatus. There are some juvenile skeletons of Tursiops, too.
The middle ear of Tursiops truncatus will be small compared to the middle ears of other whales. I don't know if this will be a convenience or a handicap. In any case, you will have to deal with a narrow range of middle ear sizes. So you won't have to keep changing your experimental set up.
Because they are so common in aquariums, the behavior of Tursiops truncatus is most studied. Already, scientists are studying the so called language of the dolphin. Much of the "language" involves sound. So there is live behavior to correlate your experimental results with.
There is a large interest in Tursiops truncatus. The medical care of Tursiops truncatus is of interest since they are commonly kept in zoos. There is also a big animal rights issue. People want to save Tursiops truncatus from the tuna nets so Tursiops can starve in over fished oceans! Conservations want to preserve Tursiops to protect the environment. The hearing of Tursiops truncatus is critical in all these topics.
I am sure there is some research done on the middle ears of Tursios truncatus. However, my feeling is that there is less known about the middle ear of Tursiops then about the affect of weather on sound. I am fairly sure that not much is known about the ears of beaked whales. The chance of finding something new with either species is larger than weather related sounds.
Note: the bigger the whale, the bigger the middle ear and the smaller the frequency of the resonances. So you may want to chose your whale species according to what range of frequencies your loudspeakers can put out.