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Sarah Wells

Doctor of Philosophy, (Conservation Biology)
Study Completed: 2015
College of Sciences


Thesis Title
Evolutionary consequences and fitness correlates of extra-pair mating in the tui, Prosthemadera novaeseelandiae

Read article at Massey Research Online: MRO icon

Tui, Prosthemadera novaeseelandiae, exhibit extreme sexual size dimorphism in body size and in the size of a white throat ornament. Yet, it is not known how these traits have evolved. To determine if female mate choice has led to the evolution of these traits, Ms Wells investigated extra-pair paternity and it''srelation to fitness in the tui. She found that tui have one of the highest rates of extra-pair paternity known. Males that gained greater paternity were either large males, or had large throat ornaments. These males provided direct and indirect fitness benefits for offspring. Ms Wells''sfindings indicate that extra-pair paternity creates significant selection pressures on these male traits, which has led to the evolution of one of the highest levels of sexual size dimorphism of any socially monogamous bird.

Associate Professor Weihong Ji
Professor Dianne Brunton
Professor James Dale
Dr Dianne Gleeson