Data from: Costs and benefits of polyandry in a placental poeciliid fish Heterandria formosa are in accordance with the parent-offspring conflict theory of placentation

In viviparous species, a conflict over maternal resource allocation may
arise between mothers and embryos, between siblings, and between maternal
and paternal genes within an embryo due to relatedness asymmetries. We
performed two experiments to study the effects of polyandry and brood
relatedness on offspring growth in a placental fish (Heterandria formosa).
Polyandry was beneficial as it increased the probability of pregnancy,
possibly to avoid genetic incompatibility. However, females mated to four
males produced offspring that had a longer maturation time than those of
monandrous females. When within-brood relatedness was manipulated, the
size of the newborn offspring decreased with time in low relatedness
treatment, while in highly related broods offspring size was constant. Low
within-brood relatedness may lead to less cooperative offspring in terms
of resource extraction from the mother, which may lead to impaired
development during gestation. Offspring conflict may thus reduce the
benefits of polyandry in viviparous species.

male_behaviour_polyandryThis data file contains data about male behaviour
during the polyandry experimentpolyandry_sl_at_birthThis data file
contains data on offspring sizes (standard length) at birth in the
polyandry experimentpolyandry_male_offspringThis data file contains male
offspring sizes and ages at maturity in the polyandry
experimentpolyandry_female_offspringThis data file contains female
offspring sizes and ages at maturity in the polyandry
experimentpolyandry_number_of_offspring_producedThis data file contains
numbers of offspring produced, proportion of dead-borne offspring and time
until first birth in the polyandry
experimentBrood_relatedness_offspring_sizesThis file contains offspring
sizes at birth in the brood relatedness
experiment.Brood_relatedness_survival_analysisThis file contains data used
in survival analysis as well as offspring production data from the brood
relatedness experiment.