Data from: Transgenerational plasticity and environmental stress: do paternal effects act as a conduit or a buffer?

For most organisms, early life-history stages are the most sensitive to
environmental stress and so transgenerational phenotypic plasticity,
whereby the parental environment and offspring environment interact to
alter the phenotype of the offspring, is viewed as key to promoting
persistence in the face of environmental change. While there has been
long-standing interest in the role of transgenerational plasticity via the
maternal line (traditionally the field of maternal effects), increasingly
it appears that paternal effects can also play a role. Despite the
emerging role of paternal effects in studies of global change, key
knowledge gaps remain: first, whether paternal effects act to increase or
decrease offspring performance remains largely unexplored; second, the
relative roles of maternal and paternal effects are rarely disentangled;
and third, the role of environmental variation, a key determinant of the
benefits of transgenerational plasticity, has not been explored with
regard to paternal effects. Here, we explore all three issues using the
marine tubeworm Galeolaria caespitosa, an important habitat-forming
species in southern Australia. We found that both paternal and maternal
experiences affected key stages of offspring performance (fertilization
and larval development) and, surprisingly, paternal effects were often
stronger than maternal effects. Furthermore, we found that paternal
effects often reduced offspring performance, especially when environments
varied compared with when environments were stable. Our results suggest
that, while transgenerational plasticity may play an important role in
modifying the impacts of global change, these effects are not uniformly
positive. Importantly, paternal effects can be as strong, or stronger,
than maternal effects and environmental variability strongly alters the
impacts of paternal effects.