Let's say a female antbird is hanging out with her male partner. The two lovebirds are perched there on a branch and along comes an attractive, single female antbird. The male starts to sing his song. But before attractive, single female antbird can even hear the first note, the male's parter starts singing over his song. This is in an attempt to "jam the signal," or interrupt her man-bird and prevent him from openly flirting, find researchers at the University of Oxford.
Singing over her mate may be a way to make him appear less attractive, or a way of saying, "keep off, he's mine," show the study findings, which appear in the March 12 issue of the journal Current Biology.
"In a series of playbacks, researchers found that resident pairs of antbirds sing coordinated duets when responding to rival pairs. But under other circumstances, cooperation breaks down, leading to more complex songs. Specifically, females respond to unpaired sexual rivals by jamming the signals of their own mates, who in turn adjust their signals to avoid the interference," reports a press release.
Said lead author Joseph Tobias, "Most evidence points to vocalizations in early humans having a function in both mate attraction and resource defense, so it seems plausible that 'signal jamming' and especially 'jamming avoidance' played a role in our evolutionary history. If so, our results may help to explain the first steps towards complex, coordinated group signals in humans."
Ah, signals not dissimilar to those we've observed at dinner parties where married couples mingle with singles. This reminds us of those moments when we spot a single talking to a married. And then, within minutes, the married's partner gets some sort of radio-frequency alert and enters the frame, draping a hand on the shoulder or curling hairs around the ear, as if to say, "Honey, this one's taken."
Isn't biology just fascinating like that?