Open AccessDevelopmental Time, Body Size and Wing Loading in Drosophila Buzzatii from Lowland and Highland Populations in Argentina
Author(s) -
Norry Fabian M.,
Bubliy Oleg A.,
Loeschcke Volker
Publication year - 2001
Publication title -
hereditas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.819
H-Index - 50
eISSN - 1601-5223
pISSN - 0018-0661
DOI - 10.1111/j.1601-5223.2001.t01-1-00035.x
Subject(s) - wing , biology , population , altitude (triangle) , adaptation (eye) , wing loading , ecology , selection (genetic algorithm) , stabilizing selection , genetic variation , demography , genetics , geometry , mathematics , neuroscience , artificial intelligence , sociology , angle of attack , computer science , gene , engineering , aerodynamics , aerospace engineering
Genotype‐by‐temperature interaction is a necessary condition for adaptive evolution of fitness traits as a response to temperature. Several fitness‐related traits (developmental time, pre‐adult survival, thorax and wing lengths, and wing loading) were measured in laboratory‐reared D. buzzatii from four populations sampled at different altitudes in north‐western Argentina: a lowland population (407 m a.s.l.), two populations from intermediate altitude (780 to 950 m a.s.l.), and a highland population (2380 m a.s.l.). Temperature is the main climatic difference between the collection sites: lowland but not highland populations are exposed to physiologically high temperatures during both spring and summer in nature. Three growth temperatures (20, 25 and 30°C) were used to test for population‐by‐temperature interactions. Both developmental time and pre‐adult survival exhibit highly significant population‐by‐temperature interaction. Pre‐adult survival at 30°C is significantly higher in lowland than in highland populations, but not so at lower growth temperatures (20 and 25°C). Both wing length and wing loading show no population‐by‐temperature interaction, indicating that these traits are not the direct targets of thermal adaptation in nature. Wing loading is higher in highland than in lowland populations, suggesting that flight performance is subject to stronger selection in the highland population. This hypothesis is consistent with ecological observations in both types of populations. There is no obvious among‐population relationship between developmental time and body size, even though both traits are related within populations in a well‐known trade‐off. Overall, thermal adaptation is evident for developmental time and pre‐adult survival but not for size‐related traits.