Tokyo seminar: Kazuo Okanoya
On Thursday, May 31, we will have another Tokyo Life and Mind seminar (Komaba 16-107, 12:30). We are happy to have Prof Okanoya, who is doing fascinating comparative research on the evolution of language.
Evolution of song complexity in Bengalese finches: Domestication as a relaxing force and sexual selection as a canalizing force
Prof Kazuo Okanoya
University of Tokyo
The Bengalese finch (BF) is a domesticated strain of the White-Rumped Munia (WRM). WRMs are wild species of songbirds living all over South-East Asia. WRMs were imported in Japan about 250 years ago and they were began to be called as BFs. They were artificially selected for their parental behavior and white color morphs and the process of selection was well documented in literature. Although BFs were never explicitly selected for their song, songs also changed radically through the process of domestication. WRM songs are wide-banded and noisy but sequence of song notes are highly fixed and stereotyped. BF songs are narrow-banded and louder, and song notes are arranged in a complex order. We hypothesized that the strain differences in songs are due to domestication and sexual selection. We also wanted to find neural correlates of song complexity in BFs. In this talk, we will give an overview of the evolution of song complexity in BFs in terms of Tinbergen’s Four Questions (mechanisms, development, function, and evolution), and then extend our hypothesis in terms of the relaxed selection and masking hypothesis proposed by Terrence Deacon.
Okanoya, K. (2012) “Behavioural Factors Governing Song Complexity in Bengalese Finches.” International Journal of Comparative Psychology, 25: 44-59.
Okanoya, K. (2004) “Song Syntax in Bengalese Finches: Proximate and Ultimate Analyses.” Advances in the Study of Behaviour, 34: 297-346.