Comprehensive study of ~400 taxa, from 1958 to 2002. (>115,000 samples) Sir Alister Hardy Foundation for Ocean Science, The Laboratory, Citadel Hill, Plymouth, UK Impact of climate change on marine pelagic phenology and trophic mismatch. Edwards, M. and A.J. Richardson, 2004. Nature, 430: 881. Climate impact on plankton ecosystems in the Northeast Atlantic. Richardson, A.J. and D.S. Schoeman, 2004. Science, 305: 1609. Warming of oceans: life history and trophic mismatch
Time Amount Trophic Mismatch “Phytoplankton” “Larvae”
Physiology – The Science of “How Organisms Work” Complex Life Histories
The Larval Biology “Black Box” Food limitation, predation, transport, dispersal etc. Eggs Recruitment <<1% Larval Mortality
Phenotype (Variation in Survival and Growth) Genetic Crosses GenomicsPhysiology Complex Traits: Life Span Feeding, Metabolism Measure & Predict? Themes for Today’s Presentation
Different growth rates in similar environment of food and temperature (N = 35 different larval families) Up to a 4-times faster growth rate Data from Pace et al., 2006 J. Exp. Mar. Biol. Ecol.
Large-scale Culturing Experiments (200-liter vessels x 20 units = 4,000 liters) ~2 million individuals of same larval family per culture vessel
Physiological bases of growth differences under same environmental conditions Growth = [Energy In] minus [Energy Out] feedingmetabolism & excretion Particulate (algae) Dissolved nutrients (transport rate) Energy consumption - metabolic rate - growth efficiency - aerobic capacity (citrate synthase) - ion regulation (ATPase) Loss of ingested food - absorption efficiency Difference in slow and fast growing larvae No difference Condition index - mass - volume Data from Pace et al., 2006 J. Exp. Mar. Biol. Ecol.
Fast growing larvae possess higher size-specific feeding rates
Physiological scaling of ~2-fold higher feeding rates set genetically Fast-growing larval families) Slow-growing larval families) Average feeding rate at 220 µm (N = 332) Fast-growers = 21.7 µl larva -1 h -1 Slow-growers = 11.4 µl larva -1 h -1 ~ 2-times faster
Similar size-specific metabolic rates Not ‘simple’ reduction in rate 5353 3535 3333 Fast-growing larvae Slow-growing larvae
2525 2222 5555 Fast-growing larvae Slow-growing larvae Similar size-specific metabolic rates Not ‘simple’ reduction in rate
Physiological regulation of differential growth rates 1.Feeding: ~ 50% of growth rate variation 2. Metabolic regulation: Not total metabolic rate, but differential energy allocation efficiency (mechanism?)
The high cost of growth (protein) Protein growth Protein synthesis Protein degradation From Pace and Manahan, 2006 J. Exp. Biol. (sea urchin larvae)
Feeding rate How to grow faster in the same environment? 50% Metabolism: Protein depositional efficiency
Biological Variation [e.g., growth; size; feeding; physiological rates; etc.] Vast majority of adaptive traits show complex inheritance – i.e., likely many genes contributing to a complex trait Hard to unravel the connections between genes, complex traits, and adaptation.
Genomic Analysis of Differential Growth ♂ Line 3 ♀ Line 5 ♂ Line 5 ♀ Line 3 3x3 5x3 3x5 5x5 Reciprocal cross between parental lines Larval families with differential growth ANOVA, P<0.05
Transcriptome analysis ‘Slow-growth genes’ ‘Fast-growth genes’ Shared genes cDNAs cloned on beads (MegaClone TM ) Sequences read & counted (MPSS: Massively Parallel Signature Sequencing TM ) Slow-growingFast-growing Advantages of MPSS: High sensitivity ( 3 tpm.) No a priori sequence needed Gene ID by ‘signature sequence’ Brenner et al, 2000 Nature Biotech. 18:630
Matches to genes annotated in Gene Ontology Its more than environment, and its more than simple additive genetics Functional Category Protein Synthesis Chromosome Organization Electron Transport ATP Synthesis Endocytosis Protein Folding Regulation of Metabolism Response to Oxidative Stress 62% http://www.GeneOntology.org/ 60%
“Building the Organism” Growth Physiology (Variation in Size) Number of genes = ? 10? 100? 1,000? 10,000? Developmental Biology (Egg to Larva) Requires 1000s of genes
Highly complex metabolism What to measure? How to predict?
Food from the ocean – Hybrid animal protein production Worldwide production of C.gigas = 4.4 M metric tons ($3.7 billion) FAO Yearbook of Fishery Statistics, 2003
Phenotype (Variation in Survival and Growth) GenomicsPhysiology Physiological Genomics Define mechanisms of growth and survival based on known Phenotypic Contrasts
Recruitment: Population Connectivity and Dynamics, Species Management … RECRUITMENT BIOLOGY Ecology, Evolution Physiology, Biochemistry Cellular, Molecular Chemical Environment Nutritional; chemo-sensory Physical Environment Currents; hydrography