CIE Spotlight: Climate-related spatial and temporal variation in bill morphology over the past century in Australian parrots

Daniel C.T. and Matthew S.

Daniel C.T. and Matthew S.

TitleClimate-related spatial and temporal variation in bill morphology over the past century in Australian parrots

AuthorsDaniel J. E. Campbell-Tennant, Janet L. Gardner, Michael R. Kearney and Matthew R. E. Symonds

Source: Journal of Biogeography, Volume 42, Issue 6, pages 1163–1175, June 2015

Brief summary of the paper: In this paper we show that not only do parrots that live in warmer climates in Australia have larger bills (most likely in order to help shed excess heat loads), but that in four of the five species we examined (mulga parrots, gang-gang cockatoos, red-rumped parrots and crimson rosellas) there has been an increase in bill size since 1871.

By using museum specimens collected over the past 145 years, we found a between 4 and 10% increase in bill surface area over that time.

These changes are consistent with the increases in climatic temperature experience over the past century, although the patterns may also indicate the influence of other facts such as changes in habitat or food availability.