They have radios stationed in all boats.
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Well, there are radios in MOST ships, and many boats. Besides radio, ships communicate with each other by horn signals. There is a standard set of signals that indicate actions that a ship is about to take.
Boats (people) can communicate silently with flags or light signals.
Plants cannot communicate with one another.
Electronically.
They communicate with each other by touching their antennae with one another. If red ants come upon another ant they do so to tell if they are from the same nest.
Boats and gold
talking
they grunt to communicate
morse code.
We communicate using sound waves by talking and listening to one another!
a wolf communicates with one another with it's spine tingling howl
safety boats
They used smoke signals to communicate with one another.