Sex allocation studies seek to ascertain whether mothers manipulate offspring sex ratio prior to ovulation. To do so, DNA for molecular sexing should be collected as soon after conception as possible, but instead neonates are usually sampled. Here, we aim to identify and quantify some of the problems associated with using molecular techniques to identify the sex of newly laid avian eggs. From both fertilized and unfertilized c...

Sex identification is a problem in research and conservation. It can often be solved using a DNA test but this is only an option if a sex‐specific marker is available. Such markers can be identified using the amplified fragment length polymorphism (AFLP) technique. This is usually a taxonomic method, as it produces a DNA fingerprint of 50–100 PCR bands. However, if male and female AFLP products are compared, sex‐specific marke...

Birds are difficult to sex. Nestlings rarely show sex‐linked morphology and we estimate that adult females appear identical to males in over 50% of the world's bird species. This problem can hinder both evolutionary studies and human‐assisted breeding of birds. DNA‐based sex identification provides a solution. We describe a test based on two conserved CHD (chromo‐helicase‐DNA‐binding) genes that are located on the avian sex ch...