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Because they are large enough to be useful, simple to create, and ever–present. No organism “knows” or “plans” the evolution of its species; it is random. Of c
by db48x 4y ago
Because they are large enough to be useful, simple to create, and ever–present.
No organism “knows” or “plans” the evolution of its species; it is random. Of course, if we were created then that’s another matter. In that case, our Creator knew that sound waves are large enough to be useful and that we would have a convenient atmosphere around at all times to create them in.
Magnetic fields, on the other hand, are tiny and difficult to manipulate. The same goes for gravity too, except more so. Gravity is 40 orders of magnitude weaker than the electroweak force. A small magnet can lift some paperclips, but to do the same with gravity you would have to dangle Venus above your desk. The strong force is even more useless.
There are no other forces. That’s all there is; electromagnetism, the weak force (which is really part of the electromagnetic force), the strong force, and gravity. Well, those four plus atoms bumping into each other, but atoms bump into each other using the electromagnetic force.
- gus_massa 4y agoI fully agree, but I can't resist nitpicking: There is a detector of gravity in/near the earhttps://en.wikipedia.org/wiki/Vestibular_system https://en.wikipedia.org/wiki/Vestibular_system It detects average gravity and is used for balance. But it (obviously) does not detect gravitational waves. As the other comment said, some birds can detect magnetic field. And also some bacteria (archea?). They are also low sample rate detectors, enough to detect the direction (but IIRC not the strength).
- beardyw 4y ago"a 2019 study found that magnetic fields do affect human alpha brain waves, but it is not known whether this results in any change in behaviour" Magnetoreception - Wikipedia https://en.m.wikipedia.org/wiki/Magnetoreception https://en.m.wikipedia.org/wiki/Magnetoreception
- db48x 4y agoYou’re right, I’d forgotten about that. The otoliths can detect the pull of the whole Earth, but gravity is so weak that anything smaller than a planet is undetectable.