Doug BrotherofCats Dandridge

In an earlier post we looked at the possible alien sense of sight and possibilities other than sight to produce a picture of the world. Things such as sonar and radar were also discussed. Now on our world some animals have much better hearing than vision, and it seems to serve them well. Dogs and cats have a much higher range of hearing, and dogs can hear rodents running through the ground across a field. In fact dogs can hear four tones for every one we hear, which means that perfectly tuned guitar might sound horribly out of tune to them. Now hearing is best in animals which live in environments where sight might be limited. Sight hounds like Afghans and Greyhounds do not have quite the hearing of their cousins, though it is still very good. But their eyes are much better, since they hunt across open plains. Our hearing is adequate for our purposes, though our eyes are superior in most respects to any other animal. We don’t allocate as much brain area to hearing as we do to sight. Our visual cortex takes up an entire lobe, about a quarter of our brain mass. Hearing a small section of one. But we hear well enough to communicate, and that seems to be enough for a well sighted like us. Speaking about communication, research shows that deaf people are on the whole more depressed than blind people. Seems that the sound of another human communicating to us is important to our psychological well being. But I still always thought I could do better deaf than blind. Then again, as a writer I can work without having to hear anything, while being without vision would be a pure bitch. So what would the hearing be like for another intelligent species? And could it be the dominant sense?
In Star Trek Spock had superior hearing because the atmosphere of Vulcan was thinner than Earth’s. It would make sense for organisms that developed in a thinner atmosphere to have superior hearing to a similar Earth animal for the simple reason that less dense atmospheres conduct sound at a slower and less robust rate. Also, the more stealthy predators there are the better the hearing should be. Now in space hearing is a sense that could be done without. Not that it isn’t useful, but sound doesn’t transmit in a vacuum, and visual displays could handle all communication. So there could be space faring races that are completely deaf, though not having the utility of hearing on a planet’s surface is still a detriment. Having something sneak up on you that isn’t really stealthy, because you can’t hear, would be an embarrassing way to die. Of course another sense like 360 radar sense or vision might compensate, but if the creature has to sleep hearing is a good sense for picking up the approach of an intruder and waking one up.
So what about for communication? Visual signals or scents might do the job, but good old talking, yelling whatever covers a good distance and goes around corners. Hearing seems like to useful a sense to leave out of the package for most creatures. So will there be intelligent creatures that are deaf, or at least don’t possess hearing organs, depending on picking up vibrations in other ways? Probably, but I would still put my money on most of them having hearing organs of some type, and picking up sounds for communications and survival purposes. They might have hearing organs like we do, and two seem to do a good job at giving us a directional sense of hearing, but hearing vibrations through the skin might do the job. Hearing in the lower ranges might do as well as hearing across all ranges, but there is a reason that animals with sensitive hearing have such a good range, much higher than our own. And of course we would expect intelligent creatures to not have as good a sense of hearing as lower animals on their world, or would we. There are all kinds of possibilities, and I don’t think we can rule any out just based on our own world examples.