There's a couple things here:
1. Extremophiles evolved progressively to more difficult ecosystems. They came from organisms that could manage in chemically unreactive of mostly water/salt water. It's unlikely the precursors to life, like prions or unbound mRNA chains would've "made it" in arsenic lakes or boiling lakes. But some prokaryotes could manage in environments with a little arsenic, and evolution could work its magic.
Like the creationists say, getting something as complex and robust as a modern organism "randomly" would be a bit like a tornado blowing through a junk yard and assembling a car.
2. The utility of radio waves for communication wouldn't hinge much on the physic form of an organism, just something much like sapience.