Advanced

Interfemale variation in egg yolk androgen allocation in the European starling: do high-quality females invest more?

Pilz, KM; Smith, Henrik LU ; Sandell, Maria LU and Schwabl, H (2003) In Animal Behaviour 65(4). p.841-850
Abstract
Androgenic hormones occur naturally in bird egg yolk and are known to enhance growth in canary and gull chicks. Gil et al. (1999, Science, 286, 126-128) have recently proposed that female allocation of androgens to eggs represents a form of costly maternal investment. This hypothesis predicts that females of high quality or high reproductive potential should invest more yolk androgens in their eggs than females of low quality or low reproductive potential. We tested these predictions by examining interfemale variation in allocation of the androgenic steroids testosterone and androstenedione to eggs in a wild population of European starlings, Sturnus vulgaris. We collected 30 full clutches of eggs and captured 22 of the females that laid... (More)
Androgenic hormones occur naturally in bird egg yolk and are known to enhance growth in canary and gull chicks. Gil et al. (1999, Science, 286, 126-128) have recently proposed that female allocation of androgens to eggs represents a form of costly maternal investment. This hypothesis predicts that females of high quality or high reproductive potential should invest more yolk androgens in their eggs than females of low quality or low reproductive potential. We tested these predictions by examining interfemale variation in allocation of the androgenic steroids testosterone and androstenedione to eggs in a wild population of European starlings, Sturnus vulgaris. We collected 30 full clutches of eggs and captured 22 of the females that laid these clutches for phenotypic measurements. In agreement with the hypothesis, we found that there was significant interfemale variation in yolk androgen concentrations. Furthermore, older females deposited more androstenedione and testosterone in eggs than 1-year-old females, and females laying early or large clutches deposited more testosterone in eggs than females laying late or small clutches. However, females in good body condition did not deposit more androgens in eggs than females in poor body condition. Large-yolked eggs had a higher total yolk androgen content than small-yolked eggs, but larger eggs did not have higher concentrations of yolk androgens. The results in general support the investment hypothesis of yolk androgen allocation. However, further data are needed regarding the costs of yolk androgen allocation and the effects of yolk androgens on offspring to substantiate the assumptions of the hypothesis. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Animal Behaviour
volume
65
issue
4
pages
841 - 850
publisher
Elsevier Ltd
external identifiers
  • wos:000183484900022
  • scopus:0037392847
ISSN
1095-8282
DOI
10.1006/anbe.2003.2094
language
English
LU publication?
yes
id
007e688c-f8f4-487c-bfe4-5a31b85bf213 (old id 137294)
date added to LUP
2007-06-25 12:45:05
date last changed
2018-10-03 11:10:09
@article{007e688c-f8f4-487c-bfe4-5a31b85bf213,
  abstract     = {Androgenic hormones occur naturally in bird egg yolk and are known to enhance growth in canary and gull chicks. Gil et al. (1999, Science, 286, 126-128) have recently proposed that female allocation of androgens to eggs represents a form of costly maternal investment. This hypothesis predicts that females of high quality or high reproductive potential should invest more yolk androgens in their eggs than females of low quality or low reproductive potential. We tested these predictions by examining interfemale variation in allocation of the androgenic steroids testosterone and androstenedione to eggs in a wild population of European starlings, Sturnus vulgaris. We collected 30 full clutches of eggs and captured 22 of the females that laid these clutches for phenotypic measurements. In agreement with the hypothesis, we found that there was significant interfemale variation in yolk androgen concentrations. Furthermore, older females deposited more androstenedione and testosterone in eggs than 1-year-old females, and females laying early or large clutches deposited more testosterone in eggs than females laying late or small clutches. However, females in good body condition did not deposit more androgens in eggs than females in poor body condition. Large-yolked eggs had a higher total yolk androgen content than small-yolked eggs, but larger eggs did not have higher concentrations of yolk androgens. The results in general support the investment hypothesis of yolk androgen allocation. However, further data are needed regarding the costs of yolk androgen allocation and the effects of yolk androgens on offspring to substantiate the assumptions of the hypothesis.},
  author       = {Pilz, KM and Smith, Henrik and Sandell, Maria and Schwabl, H},
  issn         = {1095-8282},
  language     = {eng},
  number       = {4},
  pages        = {841--850},
  publisher    = {Elsevier Ltd},
  series       = {Animal Behaviour},
  title        = {Interfemale variation in egg yolk androgen allocation in the European starling: do high-quality females invest more?},
  url          = {http://dx.doi.org/10.1006/anbe.2003.2094},
  volume       = {65},
  year         = {2003},
}