CER researchers investigate the song of the collared flycatcher with computer simulations in order to understand animal cultures

Birdsong often develops through social learning as well, and species with simple and complex songs both exist. The song of the collared flycatcher (Ficedula albicollis) is quite complex, and one of its populations in the Pilis region has been continuously studied by behavioral biologists for over 20 years. Similar to human music, birdsong can be broken down into elementary units called syllables. Based on the researchers' records, an individual in the studied Pilis population sings approximately 20-100 syllable types, while in the population as a whole more than a thousand syllable types have been recorded over the years. Furthermore, the syllable repertoire of a population continuously changes over the years.

In a recently published study, CER researchers examined whether assumed simple mechanisms during the learning process explain the song patterns observed in the field for the collared flycatcher. They constructed an individual-based computer model in which the life history characteristics of the individuals resembled those of the collared flycatcher. They hypothesized that young individuals learn new syllables from older ones, in a way that they are more likely to sing the syllables they have heard more frequently later on. They also considered that learning is not entirely accurate: occasionally, the learning individual starts singing something different from the syllables they have heard. Additionally, the researchers also incorporated in the model the continuous influx of individuals from distant populations, bringing new syllables with them.

Using the model, they demonstrated that these mechanisms, which have contrasting effects on cultural diversity, are capable of maintaining a complex polymorphic birdsong culture. In the model, cultures with long-lasting metastable states and high diversity persisted, which collapsed due to random effects over time and stabilized at lower diversity. Within a certain range of parameters, the syllable patterns calculated from the model and observed in the field exhibit similar characteristics. However, the differences between the model and field data highlight the need to consider additional mechanisms in future models, such as the spatial structure of the population, the occurrence of syllables in the linked songs, or the females' preferences for specific syllables.

 Publication:

Barta, K. A., Garamszegi, L. Zs., Scheuring, I., Zsebők, S. (2023). Effects of positive frequency-dependent learning, learning mistakes, and immigration on complex cultures–Validation on the song of collared flycatcher (Ficedula albicollis) by individual-based modeling. Frontiers in Ecology and Evolution. DOI: 10.3389/fevo.2023.1040550