Why females cheat with old males
Research report (imported) 2014 - Max Planck Institute for Ornithology
Anisogamy leads to females being expected to be the choosier sex. However, when females cheat on their social partners, they seek males as mates that are older than their social partner but with whom they produce offspring of lower fitness. This is what a team around researchers of the MPI for Ornithology found in house sparrows. Also, old mothers produced daughters of low fitness compared to young mothers. These findings are important, as this patterns has been found to a limit also in humans. Thus, with increasing age of reproduction we may pass on the costs of this to the next generation.