Open Access
Variation in developmental trajectories of physiological and somatic traits in a common songbird approaching fledging
Author(s) -
Allison Cornell,
Tony Williams
Publication year - 2017
Publication title -
journal of experimental biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.367
H-Index - 185
eISSN - 1477-9145
pISSN - 0022-0949
DOI - 10.1242/jeb.162248
Subject(s) - songbird , fledge , variation (astronomy) , biology , somatic cell , evolutionary biology , zoology , ecology , genetics , predation , physics , astrophysics , gene
In avian species, little is known about the development of physiological traits in the days preceding fledging, a critical life history transition marked by a high mortality rate. Developmental trajectory during this period may be flexible based on ecological context or hardwired, with potential costs for variation in growth in the form of oxidative stress. Patterns in development are likely to relate to variation in life history, for which seabirds and aerial insectivores have been well studied, while our focal species is a grassland ground forager, the European starling (Sturnus vulgaris). We show that changes in hematocrit, body mass, and wing length are independent of year and brood quality, while changes in hemoglobin concentration are higher in low quality broods. Moreover, we also identify higher oxidative stress in low quality year and second broods, a potential cost for maintaining a hardwired developmental trajectory in a lower quality environment. Finally we experimentally test the effects of food supplementation on development and maturity of chicks at fledging to show that although food increases body mass early in development, it does not change the trajectory or final maturity of chicks at fledging. Collectively this study demonstrates that some developmental changes prior to fledging may be hardwired, but may have long-term oxidative costs in low quality environments.