Mechanisms behind lifehistory tradeoffs molecular genetics dynamic energy

Mechanisms behind lifehistory trade-offs molecular genetics dynamic energy budgets evolutionary ecology Tjalling Jager

Trade-offs A ‘beneficial’ change in life-history trait connected to a ‘detrimental’ change in another Trade-offs … • constrain evolutionary pathways • information on mechanisms underlying traits • environmental relevance: ‘costs for tolerance’

Compare two strains molecular level life-history traits

Compare two strains molecular level metabolic organisation life-history traits Ø Molecular level affects traits unspecifically • no unique (set of) gene(s) exist for a single trait Ø Traits themselves cannot be independent • traits are constrained by mass and energy balance Ø Strong theory exists for allocation rules

Metabolic organisation Dynamic mass and energy budgets SOURCE SINKS maturation maintenance

Metabolic perspective Change in one energy-budget parameter: fraction allocated reserves to growth vs. reproduction

Costs of tolerance Ø Under long-term exposure, tolerance can evolve • e. g. , metals and pesticides Ø Trade-offs: associated metabolic costs? sensitive tolerant somatic maintenance increased by 25% sensitive tolerant

Research approach theory and models full lifecycle data validation primary energybudget parameters tolerance patterns & trade-offs genotypic differences population effects

Research approach theory and models full lifecycle data validation primary energybudget parameters tolerance Ø Strains differ in more parameters simultaneously • test large number of pure strains (RI strains) • collaboration with Dept. Nematology (WUR) Ø Difficult to extract all energy-budget parameters • perturbations (food level and toxicants) Ø Traits do not fully depend on genotype • quantify inter- and intra-genotype variation Ø How to link to genotypic differences? • QTL-mapping (strains are genotyped) patterns & trade-offs genotypic differences population effects

allocation rules maintenance rate assimilation rate costs for an egg etc. … maximum size at maturity reproduction rate etc. … po p bi ula ol tio og n y ec -his ol to og ry y lifehistory traits population effects “fitness” ol bi utio ol n og ar y y primary parameters of energy budget ev genotype or met ga ab ni ol sa ic tio n m o ge lec ne ul tic ar s Outlook: causality

genotype primary parameters of energy budget lifehistory traits po p bi ula ol tio og n y life ec -his ol to og ry y or met ga ab ni ol sa ic tio n m o ge lec ne ul tic ar s Outlook: causality population effects allocation rules ol bi utio ol n og ar y y ev variation stressors “fitness”