Assessing the usefulness of ptilochronology in the study of melanin‐ and carotenoid‐based ornaments in the Great TitParus major

Hatching Rank Influences Nutritional Condition in the Common Buzzard: Evidence from Ptilochronology

“…It is advisable to first evaluate whether ptilochronology can adequately represent nutritional condition in the study species and then apply the technique to other aspects of interest (cf. Matysiokova and Remes 2010). There is some evidence that nestlings may be able to allocate resources to important areas of development, such as feather growth, resulting in a staggered growth among different components of their physiology (e.g., Schew andRicklefs 1998, Dahdul andHorn 2003).…”

More ornamented females produce higher-quality offspring in a socially monogamous bird: an experimental study in the great tit (Parus major)

“…We photographed the bird's white cheek (i.e., right side of the head) and breast with a digital camera (Panasonic DMC-FZ5). While taking a picture of the cheek, the bird was held in a standardized position on its left side; while taking a picture of the breast, the bird was held outstretched by its tarsi and beak and photographed together with a ruler from a standard distance (see [52]). All measurements and photographs were taken by VR.…”

Multiple indices of body condition reveal no negative effect of urbanization in adult house sparrows

“…Thus, our result that neither bib size and nor wing bar size varies systematically along the urbanization gradient is in agreement with the repeated finding that urban and rural sparrows retain their differences in body mass even when receiving the same diet under identical captive conditions (Bókony et al, 2010;Liker et al, 2008), implying that adult sparrows are unlikely to face different nutritional conditions at differently urbanized habitats. Interestingly, a recent study based on ptilochronology indicated that urban house sparrows experience nutritional stress where hedges and dense bushes are highly scattered and isolated (Vangestel et al, 2010), although this conclusion has to be treated with caution because growth bar widths were measured on normally grown feathers for which the method is less well validated than for feathers with experimentally induced growth (Kern & Cowie, 2002;Matysioková & Remes, 2010).…”