ABSTRACT
Birds are the most diverse biological group among tetrapods, with more than 10,900 existing species. Molecular and morphological studies support the division of living birds into three monophyletic groups: Palaeognathae, Galloanserae, and Neoaves. Cytogenetics is a useful tool in bird cytotaxonomy, especially for groups with a great chromosome variability. Chromosome painting data are available for 117 species, which represent less than 1% of all known bird species. Avian mitotic chromosomes can be directly obtained from samples of different tissues, including kidney, liver, bulb feather, and bone marrow, as well as from embryos/eggs. The Nick translation procedure follows the manufacturer’s instructions and is appropriate when the DNA sequence of interest was already isolated by flow sorting. Different from other tetrapods, the avian genomes have only a small amount of repetitive DNAs.
