[cogman10]

I'd think it would depend a lot on the animal. Whales, for example, don't really have great eyesight. They depend a lot more on sound and have been observed communicating over long ranges (particularly because water carries sound quiet well). So it seems natural to conclude that whales would communicate more primarily through sound than other mechanisms.

[pawelwentpawel]

That's a great point, didn't think about that!