Parasite treatment affects maternal investment in sons.

@article{Reed2008ParasiteTA,
  title={Parasite treatment affects maternal investment in sons.},
  author={Thomas E. Reed and Francis Daunt and M. E. Hall and Richard A. Phillips and Sarah Wanless and Emma J. A. Cunningham},
  journal={Science},
  year={2008},
  volume={321 5896},
  pages={1681-2}
}
Parasitism can be a major constraint on host condition and an important selective force. Theoretical and empirical evidence shows that maternal condition affects relative investment in sons and daughters; however, the effect of parasitism on sex ratio in vertebrates is seldom considered. We demonstrate experimentally that parasitism constrains the ability of mothers to rear sons in a long-lived seabird, the European shag Phalacrocorax aristotelis. The effect contributes to the decline in… CONTINUE READING