Friend or Foe? Naked Mole Rats Can Tell By A Unique Squeak
What sounds like a large study found that different colonies had different "languages". They are almost blind and live in underground colonies and when one bumps into another in a tunnel, which is frequent, they make a particular bird-like squeak, and it turns out that different colonies make different sounds then.
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Making the wrong sound makes the other one an alien and they will fight.... Interrupted for dinner and I don't remember the other interesting things. The text has parts I don't remember from the audio, but wthout the audio you can't hear what they sound like.
Each colony has a queen and when she dies there is chaos until another queen is established. The researchers thought she ruled the place, another example of SWMBO.
A lot more info about them.
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