Zoologists from Trinity College Dublin, working in tropical Southeast Asia, have uncovered a modern-day example of rapid evolution in action.
The zoologists have discovered that male and female Sulawesi Babblers (Pellorneum celebense, a species of bird) have evolved to attain different sizes on small islands, and in quick-fire time. They believe this is most likely due to evolutionary pressure favouring such “dimorphism” because the birds are able to reduce competition with each other by feeding on different, scarce resources.
The research, completed with the support of the Irish Research Council and collaborators in Universitas Halu Oleo, is published today in the journal Biotropica. The research shows that the males of the Sulawesi Babbler grow to be up to 15% larger than the females — with this difference particularly marked on the smaller islands.
Fionn Ó Marcaigh, first author on the paper and a PhD Candidate in Trinity’s