Data from: Relatedness within and between leks of golden-collared manakin differ between sexes and age classes

Several hypotheses have been advanced to explain the evolution of leks, a
mating system in which males aggregate at display sites where females
choose their mates. Only a small proportion of males obtain copulations,
and why other males join the lek remains unexplained. One hypothesis has
called kin selection into play: if juvenile males join leks where their
relatives display and contribute to attract females to the lek, they can
gain indirect fitness benefits. We investigated the genetic structure of
eight leks of golden-collared manakin, a tropical Passerine. Adult
court-holder males, females, and immature males were caught within lek
boundaries and the geographical location of the courts was recorded. For
court-holding males, within-lek relatedness among four leks was
significantly higher than average across-lek relatedness. Courts of more
closely related males were not spatially associated within leks.
Relatedness among immature males was relatively lower, yet higher within
than between leks. Values of relatedness and genetic differentiation among
leks were even lower for females. Thus, leks were composed of males that
were more related to each other than to other males of the population, and
the degree of relatedness decreased from court holding males to immature
males to females. This suggests that immature males explore several leks
and eventually join those where their relatives display, whereas females
appear to visit leks randomly with respect to relatedness. Our results
provide support for the hypothesis that kin selection influences the
evolution of lekking behavior in this species.