Data from: The role of heritable and dietary factors in the sexual signal of a Hispaniolan Anolis lizard, Anolis distichus

The diversity of sexual signals is astounding, and divergence in these
traits is believed to be associated with the early stages of speciation.
An increasing number of studies also suggest a role for natural selection
in driving signal divergence for effective transmission in heterogeneous
environments. Both speciation and adaptive divergence, however, are
contingent on the sexual signal being heritable, yet this often remains
assumed and untested. It is particularly critical that the heritability of
carotenoid-based sexual signals is investigated because such traits may
instead be phenotypically plastic indicators of an individual’s quality
that exhibit no or little heritable variation. We present the first study
to investigate the relative contribution of genetic and environmental
factors to the striking diversity of dewlap color and pattern in Anolis
lizards. Using a breeding experiment with Anolis distichus populations
exhibiting different dewlap phenotypes, we raise F1 offspring in a common
garden experiment to assess whether dewlap color is inherited. We follow
this with carotenoid supplementation to investigate the influence of
dietary pigments to dewlap color variation. We find significant
differences in several aspects of dewlap color and pattern to persist to
the F1 generation (fathers: N = 19; F1 males: N = 50; P < 0.01)
with no change in dewlap phenotype with carotenoid supplementation (N =
52; P > 0.05). These results strongly support that genetic
differences underlie dewlap color variation, thereby satisfying a key
requirement of natural selection. Our findings provide an important
stepping-stone to understanding the evolution of an incredibly diverse
signal important for sexual selection and species recognition.