Data from: The colour of paternity: extra-pair paternity in the wild Gouldian finch does not appear to be driven by genetic incompatibility between morphs

In socially monogamous species, individuals can use extra-pair paternity
and offspring sex allocation as adaptive strategies to ameliorate costs of
genetic incompatibility with their partner. Previous studies on
domesticated Gouldian finches (Erythrura gouldiae) demonstrated a genetic
incompatibility between head colour morphs, the effects of which are more
severe in female offspring. Domesticated females use differential sex
allocation, and extra-pair paternity with males of compatible head colour,
to reduce fitness costs associated with incompatibility in mixed-morph
pairings. However, laboratory studies are an oversimplification of the
complex ecological factors experienced in the wild, and may only reflect
the biology of a domesticated species. This study aimed to examine the
patterns of parentage and sex-ratio bias with respect to colour pairing
combinations in a wild population of the Gouldian finch. We utilized a
novel PCR assay that allowed us to genotype the morph of offspring before
the morph phenotype develops, and to explore bias in morph paternity and
selection at the nest. Contrary to previous findings in the laboratory, we
found no effect of pairing combinations on patterns of extra-pair
paternity, offspring sex ratio, or selection on morphs in nestlings. In
the wild, the effect of morph incompatibility is likely much smaller, or
absent, than was observed in the domesticated birds. Furthermore, the
previously studied domesticated population is genetically differentiated
from the wild population, consistent with the effects of domestication. It
is possible that the domestication process fostered the emergence (or
enhancement) of incompatibility between colour morphs previously
demonstrated in the laboratory.