Zebra finches, with their characteristic bright beaks and distinctive songs, have long fascinated bird behavior scientists. Their tendency to form long-term pair-bonds, in particular, has been the subject of several studies. Now, a recent study has found that relationships between the birds early in life can affect how they interact in the future.
The study, published in the Proceedings of the Royal Society B, gave juvenile male finches the chance to pair with either a young female finch or another young male finch. (Zebra finches will often form same-sex couples instead of mixed-sex ones). After two rounds, during which the researchers tracked which males formed couples and which did not, the male finches (now adults) were given the same opportunity with new adult female finches.
The researchers found that males who failed to bond with other male finches didn’t have any trouble bonding with the adult females. However, juvenile male finches that hadn’t made a love connection with young female finches tended to also have a hard time when it came to bonding with adult females.
The authors believe that the phenomenon known as the “loser effect” (animals that lose a fight are more likely to lose the next fight) may be to blame. In this case, rather than losing a fight, the finches just lose the love game: Males that don’t manage to snag a female are then less likely to do so the next time they get the chance. “In the mating context we have good reason to expect the same mechanism to happen,” Mylene Mariette, lead author on the study, told BBC News.
The explanation for this effect is not yet clear. One possibility is that the females could somehow tell which males had been unsuccessful in their earlier attempts, and that could have made them less willing to cozy up to those males. Alternatively, the males, their self-confidence shattered, may view themselves as less attractive, resulting in fewer pairings.
This “loser” effect may only be short-lived, however. “He may just court less attractive females. He's not a loser for life,” said Mariette. Young male finches with lady troubles will no doubt be relieved to hear that.