I agree with this assessment of how echolocation could evolve.
On a personal note I was in a martial art which at later levels involved fighting with a blindfold. It was surprising to me to find out it wasn't a trick. While much of it involved touching an opponent so one could recognize shifts in movement, I could also fight without that physical connection. I could "see" just from the simple ruffling of clothing or shifting of feet.
The most interesting part is that I gained this ability before they ever put on the blindfold. I don't know, maybe my mind realized my eyes were more of a hindrance (too easily deceived), and so stopped using them during fights.
I noticed most of the upper students and the master had this weird far off look, not even looking at you while they fought. After a week or so of everyone telling me I was now fighting like that (I hadn't noticed), the master said for me to try a blindfold. I couldn't believe it, but it made no real difference.
After that experience I started recognizing that in fact I didn't really use my eyes in a fight anymore. It was touch and sound.
This ability does raise the question however: Did ancestors of humans use echolocation? Maybe its still with us to some degree and so all we are doing is bringing out that latent potential, rather than growing a new one.
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holmes
™ Version 4.2
