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author:("shafer, Nina")
1.  Transgenerational effects of food availability on age at maturity and reproductive output in an asexual collembolan species 
Biology Letters  2011;7(5):755-758.
Transgenerational effects of environmental conditions can have several important ecological and evolutionary implications. We conducted a fully factorial experiment manipulating food availability across three generations in the collembolan Folsomia candida, a springtail species that inhabits soil and leaf litter environments which vary in resource availability. Maternal and grandmaternal food availability influenced age at maturity and reproductive output. These effects appear to be cumulative rather than adaptive transgenerational life-history adjustments. Such cumulative effects can profoundly influence eco-evolutionary dynamics in both stable and fluctuating environments.
PMCID: PMC3169046  PMID: 21411448
maternal effect; adaptive plasticity; resource variability
2.  Growth and ontogeny of the tapeworm Schistocephalus solidus in its copepod first host affects performance in its stickleback second intermediate host 
Parasites & Vectors  2012;5:90.
For parasites with complex life cycles, size at transmission can impact performance in the next host, thereby coupling parasite phenotypes in the two consecutive hosts. However, a handful of studies with parasites, and numerous studies with free-living, complex-life-cycle animals, have found that larval size correlates poorly with fitness under particular conditions, implying that other traits, such as physiological or ontogenetic variation, may predict fitness more reliably. Using the tapeworm Schistocephalus solidus, we evaluated how parasite size, age, and ontogeny in the copepod first host interact to determine performance in the stickleback second host.
We raised infected copepods under two feeding treatments (to manipulate parasite growth), and then exposed fish to worms of two different ages (to manipulate parasite ontogeny). We assessed how growth and ontogeny in copepods affected three measures of fitness in fish: infection probability, growth rate, and energy storage.
Our main, novel finding is that the increase in fitness (infection probability and growth in fish) with larval size and age observed in previous studies on S. solidus seems to be largely mediated by ontogenetic variation. Worms that developed rapidly (had a cercomer after 9 days in copepods) were able to infect fish at an earlier age, and they grew to larger sizes with larger energy reserves in fish. Infection probability in fish increased with larval size chiefly in young worms, when size and ontogeny are positively correlated, but not in older worms that had essentially completed their larval development in copepods.
Transmission to sticklebacks as a small, not-yet-fully developed larva has clear costs for S. solidus, but it remains unclear what prevents the evolution of faster growth and development in this species.
PMCID: PMC3403952  PMID: 22564512
Cercomer; Cestoda; Complex life cycle; Energy allocation; Glycogen; Life history tradeoff; Metamorphosis; Plerocercoid; Procercoid

Results 1-2 (2)