A new study has shed light on why female starlings cheat on their mates. The research, published in the journal "Animal Behaviour", found that female starlings are more likely to engage in extra-pair copulations (EPCs) with males that have a larger repertoire of songs.

The study was conducted by researchers at the University of California, Berkeley. The researchers studied a population of starlings in California and found that males that sang a greater variety of songs had more successful EPCs. This suggests that female starlings are attracted to males with a larger song repertoire because they perceive these males as being of higher quality.

The researchers also found that female starlings that engaged in EPCs were more likely to produce offspring that survived to adulthood. This suggests that EPCs may be beneficial for female starlings because they allow them to produce offspring with higher genetic diversity.

The study provides new insights into the mating behavior of starlings and suggests that female starlings may be using EPCs as a way to increase their reproductive success.

Here are some additional details about the study:

* The researchers studied a population of starlings in Albany, California.

* The researchers monitored the mating behavior of starlings over a period of three years.

* The researchers found that males that sang a greater variety of songs had more successful EPCs.

* Female starlings that engaged in EPCs were more likely to produce offspring that survived to adulthood.

* The researchers believe that EPCs may be beneficial for female starlings because they allow them to produce offspring with higher genetic diversity.

The study provides new insights into the mating behavior of starlings and suggests that female starlings may be using EPCs as a way to increase their reproductive success.